Youssef A. Kousa

Generating a conditional allele of Irf6

Youssef A. Kousa

A research team that includes Youssef A. Kousa, M.S., D.O., Ph.D., has created a novel tool to delete Interferon regulatory factor 6, which regulates how epidermal cells differentiate, multiply and migrate.

A research team has created a novel tool to delete Interferon regulatory factor 6 (Irf6), which regulates how epidermal cells differentiate, multiply and migrate.

Mutations of this critical transcription factor are implicated in two orofacial clefting disorders. As with other transcription factors, the IRF6 protein binds to specific regions of DNA and plays a role in that specific gene’s activity. With van der Woude syndrome, a rare disease that occurs in 1 in 35,000 individuals, the National Institutes of Health (NIH) says mutations to the IRF6 gene inhibit production of the IRF6 protein. That protein shortfall lies at the heart of incomplete development and stalled maturation of tissues in the skull and face. For popliteal pterygium syndrome, IRF6 mutations can trigger facial abnormalities, webbed skin, and fused fingers and toes.

According to the NIH, the IRF6 protein is active in embryonic skin cells that later become tissue in the head, face and tongue. The study authors write that DNA variation in the IRF6 gene (which issues the marching orders to make the IRF6 protein) significantly heightens risk for developing non-syndromic cleft lip and palate, one of the most common congenital defects.

Studying the function of this critical gene in preclinical models has been hobbled by the fact that experimental models created without the Irf6 allele are born with severe skin, limb and craniofacial defects and die shortly after birth.

To overcome this hurdle, the research team did a bit of creative genetic shuffling to make a conditional allele of Irf6 to test in specific tissues at specific times as the experimental animals matured.

“The experimental models with the Irf6 conditional allele were viable after birth and, in fact, showed no developmental or reproductive defects when compared with their litter mates – which provides a reassurance that this specific change does not appear to affect overall normal gene function,” says Youssef A. Kousa, M.S., D.O., Ph.D., a pediatric resident in the child neurology track at Children’s National Health System and co-lead author of the technology report published online May 8, 2017 in Genesis.

To drill down into how the conditional allele affected the experimental models, the research team bred them with other animals specially designed to illuminate the function of the conditional allele. Some genotypes were lost, as was expected. Litters that were hypothesized to experience certain rates of severe limb, skin and craniofacial abnormalities did so. Immunostaining revealed IRF6 expression throughout the spinous layer and basal ­­­– or deepest ­­­– layer of the epidermis, but such expression was lacking in wildtype and knockout embryos.

In a different group of experimental models, the researchers added the deleter strain Ella-Cre. Nineteen resulting embryos were positive for the conditional allele but showed no evidence of recombination. Eight normal embryos showed incomplete recombination.  Nine embryos showed complete recombination in tail tissue. Just one embryo phenocopied the wild type embryos.

“Our research team successfully created the conditional allele for IRF6, which will open the door to future studies of gene function in neonatal experimental models,” Dr. Kousa and colleagues conclude. “Even though the allele is capable of recombination, we saw that efficacy varied and is linked to specific cell types. One possible explanation is variation in chromatin structure at the IRF6 locus.”

Future research will explore the utility of other Cre-drivers, such as Gdf9-Cre or CAG-Cre, to provide additional clarity about the functionality of the newly derived conditional alleles.

e-learning

Gamifying e-learning for medical education

e-learning

Computer-based learning simulations and training modules hold the promise to create “virtual patients,” enhancing opportunities for real-time learning and evaluation in medical education.

Today’s e-learning platforms are often static, one-way programs or web pages that ask passive users to read text or watch a video on screen. However, the emerging generation of e-learning features dynamic visualizations and interactions that immerse the user in real-time settings. Military pilots and vehicle operators, for example, still log hours in traditional ways, such as hands-on simulation and flight time, but now also sit in front of a computer and practice tackling unique scenarios designed to challenge and improve their real-time decision making under pressure.

In medical education, computer-based learning simulations and training modules have the promise to create “virtual patients,” giving trainees and physicians the opportunity for real-time evaluation and application of evidence-based care models. Mary Ottolini, M.D., M.P.H., M.Ed., vice chair of medical education and designated institutional official, and Jeff Sestokas, M.Ed., director of the E-Learning Center, are at the forefront of developing these types of training modules for a wide variety of users with variable experience and specialty/sub-specialty expertise in pediatric medicine.

Instructional technologists, multimedia developers and members of the Children’s Academy of Pediatric Educators (CAPE) – some of the nation’s best pediatric clinicians and medical educators – all work collaboratively to design programs that achieve specific educational goals. Each platform resides in a responsive template, making it accessible on a variety of devices and highly customizable to the needs of specific learners. A multitude of online communication and educational tactics are available to enhance learning, including live and archived lectures, forums, blogs, wikis, documents, training modules, virtual simulations, quizzes, podcasts and videoconferencing. Within each platform, individual educators have the ability to customize learning experiences even further, selecting specific modules and specialty content.

“We’re taking these tools to people where they are, and delivering the content in ways that really embrace how this latest generation of trainees receives and processes information,” says Sestokas.

Designed for Children’s National and sites around the country, the majority of the 25 plus platforms and portals created so far focus on what Children’s experts know best – the unique challenges and needs of pediatric patients and their families.

Mary Ottolini

Mary Ottolini, M.D., M.P.H., M.Ed.

For example, clinical scenarios encompass more than simple clinical evaluation and diagnosis. The learning module BEARScalpel teaches surgical residents with limited prior exposure to pediatric care how to address common communication challenges that arise when interacting with pediatric patients and their families. Maybe the “digital” family has a language barrier or a child is in more grave condition than it appears and the trainee has to decide when and how to escalate the issue to an attending physician.

Another module asks participants to diagnose a three-dimensional nonverbal “digital” infant, based on visual and audio cues such as type of cry, skin tone and overall responsiveness.

This type of case-driven learning is relatively new in the universe of electronic medical education, but is showing early promise to improve students’ analytical thinking and problem solving skills.

“There is a lot of medical e-learning available,” Sestokas adds. “But not much e-learning is case-based. That’s something we’re doing that few others do, even in adult-focused medical education.”

A recently published study measured the success of one platform at achieving its educational goals. Participants had higher satisfaction, reported higher impact on knowledge and demonstrated higher scores on metrics assessing behavior change in a virtual environment when compared to the traditional format of reading. The results suggest that interactive modules are not only a preferred method of content delivery but also more likely to improve resident performance. This assessment was made possible by sophisticated tracking systems built into each platform. The data collection provides a steady stream of intelligence about user interaction with presentation format and content, and the material’s contribution to learning goals.

“These systems augment the long standing medical education practices of hands-on simulation and bedside patient care rotations, to allow us to expose trainees and physicians to more scenarios, more complications, and more challenging decisions. We know that the value of a trainee’s education is based on the quality of the cases they are exposed to,” says Dr. Ottolini. “Our goal is to equip these trainees with tools to care for pediatric patients in the future, but to also improve their ability to care for patients today, while they continue to learn.”

As a result of this innovative work, Children’s National is one of seven institutions, and the only children’s hospital, selected to receive an Accreditation Council for Graduate Medical Education (ACGME) Innovation Award that will develop next generation of learning resources for faculty and trainees around the country.

“We have the opportunity to ensure that we are doing the best possible job of training and continuously developing pediatric experts in a field that is rapidly changing and adapting,” concludes Dr. Ottolini. “The best way to do this is to develop flexible training systems that engage users, establish a habit of lifelong learning, and instill a desire for clinical care improvement.”

 


One patient-focused module creates a virtual grocery store to help patients
and families with celiac disease learn how to identify gluten-free food.

Monika Goyal

Keeping children safe from firearm-related harm

Monika Goyal

A research paper by Monika K. Goyal, M.D., M.S.C.E., and colleagues reports on the epidemiology of firearm-related violence, summarizes public health and legislative efforts and discusses the role of pediatricians in reducing firearm-related harm.

A review led by Children’s National Health System researchers presents new insights about pediatric firearm-related injuries. The findings, published May 23, 2017 in Hospital Pediatrics, show that up to 64 percent of U.S. households have firearms, and almost 40 percent of parents erroneously believe that their children are unaware of where weapons are stored. Additionally, about 22 percent of parents wrongly think that their children have never handled household firearms.

According to the Centers for Disease Control and Prevention, firearm-related injuries are leading causes of injury deaths for youths. Younger children are more likely to be victims of unintentional firearm injuries, the majority of which occur in the home. Older adolescents are more likely to suffer from intentional injuries. Homicide by firearm is the second-leading cause of death for 15- to 19-year-olds, and suicide by firearm ranks as the third-most common cause of death for children aged 10 to 19. Estimates suggest that the cost of medical treatment for firearm-related injuries suffered by youths younger than 21 exceeds $330 million.

“While this preventable public health crisis occurs in the home, pediatricians who see children in clinic or at hospitals can play a pivotal role in helping to reduce gun violence,” says Kavita Parikh, M.D., M.S.H.S., associate professor of pediatrics in the Division of Hospitalist Medicine at Children’s National and study lead author. “In the course of providing care, pediatricians can ask patients and their families about children’s access to firearms, can encourage safe storage of firearms in the home and can support research into firearm-related injury prevention.”

The review article provides an overview of the prevalence of pediatric firearm-related injuries around the nation and a summary of legislative efforts and health care-related advocacy efforts to reduce firearm injuries around the nation. It includes research by four Children’s National co-authors who comprise the institution’s newly formed firearm-injury prevention research work group. Alyssa Silver, M.D., Children’s Hospital at Montefiore, is another co-author.

The study team found that about 20,000 children are transported to Emergency Departments each year for firearm-related injuries. Youths aged 12 to 19 make up 90 percent of this total. On average, 20 U.S. children and youths are hospitalized daily for firearm-related injuries. About 50 percent of the children who are hospitalized for firearm-related injuries are discharged with a disability.

The researchers identified regional variations in the percentage of households with firearms, as well as differences in firearm ownership by race and ethnicity. Across a number of surveys, 6 percent to nearly 50 percent of families reported storing firearms safely by using such methods as trigger locks and locked storage containers. There is a mismatch in what parents report — with many saying their child would never touch a firearm – compared with children who tell researchers they handle “hidden” firearms, including by pulling the trigger. One survey of 5,000 fifth-graders and their caregivers living in three metropolitan areas found 18 percent had household firearms. Of this group, African American and Latino households had lower odds of firearm ownership than families of white, non-Latino children. Among these survey respondents, families of white non-Latino children were less likely than families of African American children to use safer strategies for firearm storage.

“While public health interventions have had varying degrees of success in improving firearm safety, the most effective programs have offered families free gun safety devices,” says Monika Goyal M.D., M.S.C.E., assistant professor of pediatrics and emergency medicine at Children’s National and senior study author. “The stark differences in how parents perceive their children would act and the children’s own recollections to researchers underscore the importance of the combination of counseling parents to talk to their children about firearms and instituting safe storage practices for household guns.”

Sabah F. Iqbal, M.D., assistant professor of pediatrics and emergency medicine at Children’s National and study co-author, adds: “Most families are willing to discuss firearm safety with health care providers. It is encouraging that when families receive safety counseling from health care professionals, they store firearms more safely within the home. Pediatricians need to ask children and their families about the presence of firearms in the home. These essential conversations can occur in any medical setting and need to begin before a child begins to walk and explore their own home.”

Screening for access to firearms within the health care setting where youths receive routine care may represent a beneficial strategy, the authors write. A recent survey conducted among 300 adolescents seen in an Emergency Department found that 16 percent reported having a gun in the home and 28 percent said they could access a loaded gun within three hours. About 50 percent of adolescents screened for firearm access said a friend or relative owned a gun.

The study authors also discuss the benefit of “rigorous, well-conducted” research of firearm-related injuries to guide the work of public health agencies, policymakers and pediatricians, as well as supporting state-level laws shown to be effective in preventing firearm injuries, such as universal background checks and firearm identification.

“Rigorous investigations, with the use of validated scoring systems, large comprehensive databases and accurate detailed reporting and surveillance of firearm access and related injury are urgently needed,” Shilpa J. Patel, M.D., M.P.H., assistant professor of pediatrics and emergency medicine at Children’s National, and co-authors conclude. “A collective, data-driven approach to public health is crucial to halt the epidemic of pediatric firearm-related injury.”

Related reading: Pediatric firearm-related injuries in the United States.

Coenzyme Q10

Supplement might help kidney disease

Coenzyme Q10

A research team was able to “rescue” phenotypes caused by silencing the fly CoQ2 gene by providing nephrocytes with a normal human CoQ2 gene, as well as by providing flies with Q10, a popular supplement.

A new study led by Children’s National research scientists shows that coenzyme Q10 (CoQ10), a popular over-the-counter supplement sold for pennies a dose, could alleviate genetic problems that affect kidney function. The work, done in genetically modified fruit flies — a common model for human genetic diseases since people and fruit flies share a majority of genes — could give hope to human patients with problems in the same genetic pathway.

The new study, published April 20 by Journal of the American Society of Nephrology, focuses on genes the fly uses to create CoQ10.

“Transgenic Drosophila that carry mutations in this critical pathway are a clinically relevant model to shed light on the genetic mutations that underlie severe kidney disease in humans, and they could be instrumental for testing novel therapies for rare diseases, such as focal segmental glomerulosclerosis (FSGS), that currently lack treatment options,” says Zhe Han, Ph.D., principal investigator and associate professor in the Center for Cancer & Immunology Research at Children’s National and senior study author.

Nephrotic syndrome (NS) is a cluster of symptoms that signal kidney damage, including excess protein in the urine, low protein levels in blood, swelling and elevated cholesterol. The version of NS that is resistant to steroids is a major cause of end stage renal disease. Of the more than 40 genes that cause genetic kidney disease, the research team concentrated on mutations in genes involved in the biosynthesis of CoQ10, an important antioxidant that protects the cell against damage from reactive oxygen.

Drosophila pericardial nephrocytes perform renal cell functions including filtering of hemolymph (the fly’s version of blood), recycling of low molecular weight proteins and sequestration of filtered toxins. Nephrocytes closely resemble, in structure and function, the podocytes of the human kidney.  The research team tailor-made a Drosophila model to perform the first systematic in vivo study to assess the roles of CoQ10 pathway genes in renal cell health and kidney function.

One by one, they silenced the function of all CoQ genes in nephrocytes. If any individual gene’s function was silenced, fruit flies died prematurely. But silencing three specific genes in the pathway associated with NS in humans – Coq2, Coq6 and Coq8 – resulted in abnormal localization of slit diaphragm structures, the most important of the kidney’s three filtration layers; collapse of membrane channel networks surrounding the cell; and increased numbers of abnormal mitochondria with deformed inner membrane structure.

The flies also experienced a nearly three-fold increase in levels of reactive oxygen, which the study authors say is a sufficient degree of oxidative stress to cause cellular injury and to impair function – especially to the mitochondrial inner membrane. Cells rely on properly functioning mitochondria, the cell’s powerhouse, to convert energy from food into a useful form. Impaired mitochondrial structure is linked to pathogenic kidney disease.

The research team was able to “rescue” phenotypes caused by silencing the fly CoQ2 gene by providing nephrocytes with a normal human CoQ2 gene, as well as by providing flies with Q10, a readily available dietary supplement. Conversely, a mutant human CoQ2 gene from an patient with FSGS failed to rescue, providing evidence in support of that particular CoQ2 gene mutation causing the FSGS. The finding also indicated that the patient could benefit from Q10 supplementation.

“This represents a benchmark for precision medicine,” Han adds. “Our gene-replacement approach silenced the fly homolog in the tissue of interest – here, the kidney cells – and provided a human gene to supply the silenced function. When we use a human gene carrying a mutation from a patient for this assay, we can discover precisely how a specific mutation – in many cases only a single amino acid change – might lead to severe disease. We can then use this personalized fly model, carrying a patient-derived mutation, to perform drug testing and screening to find and test potential treatments. This is how I envision using the fruit fly to facilitate precision medicine.”

Related resources:
News release: Drosophila effectively models human genes responsible for genetic kidney diseases
Video: Using the Drosophila model to learn more about disease in humans

test tubes

2016: A banner year for innovation

test tubes

In 2016, clinicians and research scientists working at Children’s National Health System published more than 1,100 articles in high-impact journals about a wide array of topics. A Children’s Research Institute review group selected the top articles for the calendar year considering, among other factors, work published in top-tier journals with impact factors of 9.5 and higher.

“Conducting world-class research and publishing the results in prestigious journals represents the pinnacle of many research scientists’ careers. I am pleased to see Children’s National staff continue this essential tradition,” says Mark L. Batshaw, M.D., Physician-in-Chief and Chief Academic Officer at Children’s National. “While it was difficult for us to winnow the field of worthy contenders to this select group, these papers not only inform the field broadly, they epitomize the multidisciplinary nature of our research,” Dr. Batshaw adds.

The published papers explain research that includes discoveries made at the genetic and cellular levels, clinical insights and a robotic innovation that promises to revolutionize surgery:

  • Outcomes from supervised autonomous procedures are superior to surgery performed by expert surgeons
  • The Zika virus can cause substantial fetal brain abnormalities in utero, without microcephaly or intracranial calcifications
  • Mortality among injured adolescents was lower among patients treated at pediatric trauma centers, compared with adolescents treated at other trauma center types
  • Hydroxycarbamide can substitute for chronic transfusions to maintain transcranial Doppler flow velocities for high-risk children with sickle cell anemia
  • There is convincing evidence of the efficacy of in vivo genome editing in an authentic animal model of a lethal human metabolic disease
  • Sirt1 is an essential regulator of oligodendrocyte progenitor cell proliferation and oligodendrocyte regeneration after neonatal brain injury

Read the complete list.

Dr. Batshaw’s announcement comes on the eve of Research and Education Week 2017 at Children’s National, a weeklong event that begins April 24. This year’s theme, “Collaboration Leads to Innovation,” underscores the cross-cutting nature of Children’s research that aims to transform pediatric care.

Sarah B. Mulkey

Researchers tackle Zika’s unanswered questions

Youssef A. Kousa

Youssef A. Kousa, D.O., Ph.D., M.S., is examining whether interplays between certain genes make some women more vulnerable to symptomatic Zika infections.

A Maryland woman traveled to the Dominican Republic early in her pregnancy, spending three weeks with family. She felt dizzy and tired and, at first, attributed the lethargy to jet lag. Then, she experienced a rash that lasted about four days. She never saw a bite or slapped a mosquito while in the Dominican Republic but, having heard about the Zika virus, asked to be tested.

Her blood tested positive for Zika.

Why was this pregnant woman infected by Zika while others who live year-round in Zika hot zones remain free of the infectious disease? And why was she among the slim minority of Zika-positive people to show symptoms?

Youssef A. Kousa, D.O., Ph.D., M.S., a pediatric resident in the child neurology track at Children’s National Health System, is working on a research study that will examine whether interplays between certain genes make some women more vulnerable to symptomatic Zika infections during pregnancy, leaving  some fetuses at higher risk of developing microcephaly.

Dr. Kousa will present preliminary findings during Research and Education Week 2017 at Children’s National.

At sites in Puerto Rico, Colombia and Washington D.C., Dr. Kousa and his research collaborators are actively recruiting study participants and drawing blood from women whose Zika infections were confirmed in the first or second trimester of pregnancy. The blood is stored in test tubes with purple caps, a visual cue that the tube contains an additive that binds DNA, preventing it from being cut up. Additional research sites are currently being developed.

When the blood arrives at Children’s National, Dr. Kousa will use a centrifuge located in a sample preparation room to spin the samples at high speed for 11 minutes. The sample emerges from the centrifuge in three discrete layers, separated by weight. The rose-colored section that rises to the top is plasma. Plasma contains tell-tale signs of the immune system’s past battles with viruses and will be analyzed by Roberta L. DeBiasi, M.D., M.S., Chief of the Division of Pediatric Infectious Diseases at Children’s National, and Dr. Kousa’s mentor.

A slender line at the middle indicates white blood cells. The dark red layer is heavier red blood cells that sink to the bottom. This bottom half of the test tube, where the DNA resides, is where Dr. Kousa will perform his genetic research.

For years, Dr. Kousa has worked to identify genetic risk factors that influence which fetuses develop cleft lip and palate. In addition to genetic variances that drive disease, he looks at environmental overlays that can trigger genes to respond in ways that cause pediatric disease. When Zika infections raced across the globe, he says it was important to apply the same genetic analyses to the emerging disease. Genes make proteins that carry out instructions, but viral infection disrupts how genes interact, he says. Cells die. Other cells do not fully mature.

While certain poverty-stricken regions of Brazil have recorded the highest spikes in rates of microcephaly, more is at play than socioeconomics, he says. “It didn’t feel like all of the answers lie in the neighborhood. One woman with a Zika-affected child can live just down the street from a child who is more or less severely affected by Zika.”

As a father, Dr. Kousa is particularly concerned about how Zika stunts growth of the fetal brain at a time when it should expand exponentially. “I have three kids. You see them as they achieve milestones over time. It makes you happy and proud as a parent,” he says.

Sarah B. Mulkey

Sarah B. Mulkey, M.D., Ph.D., is studying whether infants exposed to Zika in utero achieve the same developmental milestones as uninfected infants.

While Dr. Kousa concentrates on Zika’s most devastating side effects, his colleague Sarah B. Mulkey, M.D., Ph.D., is exploring more subtle damage Zika can cause to fetuses exposed in utero. In the cohort of Colombian patients that Dr. Mulkey is researching, just 8 percent had abnormal fetal brain magnetic resonance images (MRIs). At first glance, the uncomplicated MRIs appear to be reassuring news for the vast majority of pregnant women.

Dr. Mulkey also will present preliminary findings during Research and Education Week 2017 at Children’s National.

In the fetus, the Zika virus makes a beeline to the developing brain where it replicates with ease and can linger after birth. “We need to be cautious about saying the fetal MRI is ‘normal’ and the infant is going to be ‘normal,’ ” Dr. Mulkey says. “We know with congenital cytomegalovirus that infected infants may not show symptoms at birth yet suffer long-term consequences, such as hearing deficits and vision loss.”

Among Zika-affected pregnancies in Colombia in which late-gestational age fetal MRIs were normal, Dr. Mulkey will use two different evaluation tools at 6 months and 1 year of age to gauge whether the babies accomplish the same milestones as peers. One evaluation tool is a questionnaire that has been validated in Spanish.

At 6 months and 1 year of age, the infants’ motor skills will be assessed, such as their ability to roll over in both directions, sit up, draw their feet toward their waist, stand, take steps independently and purposefully move their hands. Videotapes of the infants performing the motor skills will be scored by Dr. Mulkey and her mentor, Adre du Plessis, M.B.Ch.B., Chief of the Division of Fetal and Transitional Medicine at Children’s National. The Thrasher Research Fund is funding the project, “Neurologic outcomes of apparently normal newborns from Zika virus-positive pregnancies,” as part of its Early Career Award Program.

Both research projects are extensions of a larger multinational study co-led by Drs. du Plessis and DeBiasi that explores the impact of prolonged Zika viremia in pregnant women, fetuses and infants; the feasibility of using fetal MRI to describe the continuum of neurological impacts in Zika-affected pregnancies; and long-term developmental issues experienced by Zika-affected infants.

cord blood

T-cell therapy success for relapsing blood cancer

cord blood

A unique immunotherapeutic approach that expands the pool of donor-derived lymphocytes (T-cells) that react and target three key tumor-associated antigens (TAA) is demonstrating success at reducing or eliminating acute leukemias and lymphomas when these cancers have relapsed following hematopoietic stem cell transplant (HSCT).

“There’s currently a less than 10 percent chance of survival for a child who relapses leukemia or lymphoma after a bone marrow transplant—in part because these patients are in a fragile medical condition and can’t tolerate additional intense therapy,” says Kirsten Williams, M.D., a blood and marrow transplant specialist in the Division of Hematology at Children’s National Health System, and principal investigator of the Research of Expanded multi-antigen Specifically Oriented Lymphocytes for the treatment of VEry High Risk Hematopoietic Malignancies (RESOLVE) clinical trial.

The unique manufactured donor-derived lymphocytes used in this multi-institutional Phase 1 dose-ranging study are receptive to multiple tumor-associated antigens within the cell, including WT1, PRAME, and Survivin, which have been found to be over-expressed in myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), B-cell AML/MDS, B-cell acute lymphoblastic leukemia (ALL), and Hodgkins lymphoma. Modifying the lymphocytes for several antigens, rather than a single target, broadens the ability of the T-cells to accurately target and eradicate cancerous cells.

Preliminary results demonstrate a 78 percent response rate to treatment, and a 44 percent rate of total remission for participating patients. To date, nine evaluable patients with refractory and relapsed AML/MDS, B-cell ALL, or Hodgkins lymphoma have received 1-3 infusions of the expanded T-cells, and of those, seven have responded to the treatment, showing reduction in cancer cells after infusion with little or no toxicity. All of these patients had relapse of their cancer after hematopoietic cell transplantation. The study continues to recruit eligible patients, with the goal of publishing the full study results within the next 12 months.

“Our preliminary data also shows that this new approach has few if any side effects for the patient, in part because the infused T-cells target antigens that are found only in cancer cells and not found in healthy tissues,” Dr. Williams notes.

The approach used to expand existing donor-derived TAA-lymphocytes, rather than using unselected T cells or genetically modified T-cells as in other trials, also seems to reduce the incidence of post infusion graft versus host disease and other severe inflammatory side effects. Those side effects typically occur when the infused lymphocytes recognize healthy tissues as foreign and reject them or when the immune system reacts to the modified elements of the lymphocytes, she adds.

“These results are exciting because they may present a truly viable option for the 30 to 40 percent of children who will relapse post-transplant,” Dr. Williams concludes. “Many of the patients who participated were given two options: palliative care or this trial. To see significant success and fewer side effects gives us, and families with children facing relapsing leukemia, some hope for this new treatment.”

Dr. Williams discussed the early outcomes of the RESOLVE trial during an oral presentation at the American Society for Blood and Marrow Transplantation meeting on February 22, 2017.

“The early indicators are very promising for this patient population,” says Catherine Bollard, M.D., M.B.Ch.B., Chief of the Division of Allergy and Immunology, Director of the Program for Cell Enhancement and Technologies for Immunotherapy (CETI) at Children’s National, and senior author of the study. “If we can achieve this, and continue to see good responses with few side effects, it’s possible these methods could become a viable alternative to HSCT for patients with no donor match or who aren’t likely to tolerate transplant.”

This is one of the first immunotherapeutic approaches to successfully capitalize on the natural ability of human T-cells to kill cancer, though previous research has shown significant success for this approach in reducing the deadly impact of several viruses, including Epstein-Barr virus, adenovirus, and cytomegalovirus, post HSCT. These new findings have led to the development of additional clinical trials to investigate applications of this method of TAA-lymphocyte manufacture and infusion for pre-HSCT MDS/AML, B-cell ALL, Hodgkins Lymphoma, and even some solid tumors.

Scientist with centrifuge

Giving fat cell messages a positive spin

Woman on a scale

Study findings offer hope to the nearly 2 billion adults who are overweight or obese worldwide that detrimental effects of carrying too much weight can recede. (Image source: Centers for Disease Control and Prevention)

Losing weight appears to reset the chemical messages that fat cells send to other parts of the body that otherwise would encourage the development of Type 2 diabetes, substantially reducing the risk of that disease, a team led by Children’s National Health System researchers report in a new study. The findings offer hope to the nearly 2 billion adults who are overweight or obese worldwide that many of the detrimental effects of carrying too much weight can recede, even on the molecular level, once they lose weight.

In 2015, Robert J. Freishtat, M.D., M.P.H., Chief of Emergency Medicine at Children’s National and Associate Professor of Pediatrics, Emergency Medicine and Integrative Systems Biology at The George Washington University School of Medicine & Health Sciences, and colleagues showed that fat cells (also known as adipocytes) from people who are obese send messages to other cells that worsen metabolic function. These messages are in the form of exosomes, nanosized blobs whose contents regulate which proteins are produced by genes. Exosomes are like “biological tweets,” Dr. Freishtat explains — short signals designed to travel long distances throughout the body.

Dr. Freishtat’s earlier research showed that the messages contained in exosomes from patients who are obese alter how the body processes insulin, setting the stage for Type 2 diabetes. However, says Dr. Freishtat, it has remained unclear since that publication whether these aberrant messages from adipocytes improve after weight loss.

“We’ve known for a long time that too much adipose tissue is bad for you, but it’s all moot if you lose the weight and it’s still bad for you,” he explains. “We wanted to know whether these negative changes are reversible. If you reduce fat, does the disease risk that goes along with excess fat also go away?”

Details of the study

To investigate this question, Dr. Freishtat and colleagues worked with six African American adults scheduled to receive gastric bypass surgery — a nearly surefire way to quickly lose a large amount of weight. The volunteers, whose average age was 38 years, started out with an average body mass index (BMI) of 51.2 kg/m2. (The Centers for Disease Control and Prevention considers a healthy BMI to range between 18.5 to 24.9.)

Two weeks before these volunteers underwent surgery, researchers collected blood samples and took a variety of measurements. The researchers then performed a repeat blood draw and measurements one year after the surgery took place, when the volunteers’ average BMI had dropped to 32.6.

Dr. Freishtat and colleagues drew out the adipocyte-derived exosomes from both sets of blood samples and analyzed their contents. The team reports in the January 2017 issue of Obesity that at least 168 microRNAs — the molecules responsible for sending specific messages — had changed before and after surgery. Further analyses showed that many of these microRNAs were involved in insulin signaling, the pathways that the body uses to regulate blood sugar. By changing these outgoing microRNAs for the better, Dr. Freishtat says, adipocytes actively were encouraging higher insulin sensitivity in other cells, warding off Type 2 diabetes.

Sure enough, each volunteer had better insulin sensitivity and other improved markers of metabolic health post-surgery, including lower branched chain amino acids and a two-fold reduction in their glutamate to glutamine ratio.

“These volunteers were essentially cured of their diabetes after surgery. The changes we saw in their surgery-responsive microRNAS correlated with the changes we saw in their metabolic health,” Dr. Freishtat says.

A glimpse into the future

Dr. Freishtat and colleagues plan to study this phenomenon in other types of weight loss, including the slower and steadier paths that most individuals take, such as improving diet and doing more exercise. The team expects to see similar changes in exosomes of patients who lose weight in non-surgical ways.

By further examining the aberrant messages in microRNAs being sent out from adipocytes, he says, researchers eventually might be able to develop treatments to reverse metabolic problems in overweight and obese patients before they lose the weight, improving their health even before the often challenging process of weight loss begins.

“Then, if you can disrupt this harmful signaling in combination with weight-loss strategies,” Dr. Freishtat says, “you’re really getting the best of both worlds.”

Eventually, he adds, tests might be available so that doctors can warn patients that their fat cells are sending out harmful messages before disease symptoms start. By giving patients an early heads up, Dr. Freishtat says, patients might be more likely to heed advice from physicians and make changes before it’s too late.

“If doctors could warn patients that their fat is telling their blood vessels to fill up with plaque and trigger a heart attack in 10 to 20 years,” he says, “patients might be more compliant with treatment regimens.”

Congenital heart disease and cortical growth

The cover of  Science Translational Medicine features a new study of the cellular-level changes in the brain induced by congenital heart disease. Reprinted with permission from AAAS. Not for download

Disruptions in cerebral oxygen supply caused by congenital heart disease have significant impact on cortical growth, according to a research led by Children’s National Health System. The findings of the research team, which include co-authors from the National Institutes of Health, Boston Children’s Hospital and Johns Hopkins School of Medicine, appear on the cover of Science Translational Medicine. The subventricular zone (SVZ) in normal newborns’ brains is home to the largest stockpile of neural stem/progenitor cells, with newly generated neurons migrating from this zone to specific regions of the frontal cortex and differentiating into interneurons. When newborns experience disruptions in cerebral oxygen supply due to congenital heart disease, essential cellular processes go awry and this contributes to reduced cortical growth.

The preliminary findings point to the importance of restoring these cells’ neurogenic potential, possibly through therapeutics, to lessen children’s long-­term neurological deficits.

“We know that congenital heart disease (CHD) reduces cerebral oxygen at a time when the developing fetal brain most needs oxygen. Now, we are beginning to understand the mechanisms of CHD-­induced brain injuries at a cellular level, and we have identified a robust supply of cells that have the ability to travel directly to the site of injury and potentially provide help by replacing lost or damaged neurons,” says Nobuyuki Ishibashi, M.D., Director of the Cardiac Surgery Research Laboratory at Children’s National, and co­-senior study author.

The third trimester of pregnancy is a time of dramatic growth for the fetal brain, which expands in volume and develops complex structures and network connections that growing children rely on throughout adulthood. According to the National Heart, Lung, and Blood Institute, congenital heart defects are the most common major birth defect, affecting 8 in 1,000 newborns. Infants born with CHD can experience myriad neurological deficits, including behavioral, cognitive, social, motor and attention disorders, the research team adds.

Cardiologists have tapped non­invasive imaging to monitor fetal hearts during gestation in high-­risk pregnancies and can then perform corrective surgery in the first weeks of life to fix damaged hearts. Long­ term neurological deficits due to immature cortical development also have emerged as major challenges in pregnancies complicated by CHD.

“I think this is an enormously important paper for surgeons and for children and families who are affected by CHD. Surgeons have been worried for years that the things we do during corrective heart surgery have the potential to affect the development of the brain. And we’ve learned to improve how we do heart surgery so that the procedure causes minimal damage to the brain. But we still see some kids who have behavioral problems and learning delays,” says Richard A. Jonas, M.D., Chief of the Division of Cardiac Surgery at Children’s National, and co-­senior study author. “We’re beginning to understand that there are things about CHD that affect the development of the brain before a baby is even born. What this paper shows is that the low oxygen level that sometimes results from a congenital heart problem might contribute to that and can slow down the growth of the brain. The good news is that it should be possible to reverse that problem using the cells that continue to develop in the neonate’s brain after birth.”

Among preclinical models, the spatiotemporal progression of brain growth in this particular model most closely parallels that of humans. Likewise, the SVZ cytoarchitecture of the neonatal preclinical model exposed to hypoxia mimics that of humans in utero and shortly after birth. The research team leveraged CellTracker Green to follow the path traveled by SVZ­ derived cells and to illuminate their fate, with postnatal SVZ supplying the developing cortex with newly generated neurons. SVZ­ derived cells were primarily neuroblasts. Superparamagnetic iron oxide nanoparticles supplied answers about long­ term SVZ migration, with SVZ ­derived cells making their way to the prefrontal cortex and the somatosensory cortex of the brain.

“We demonstrated that in the postnatal period, newly generated neurons migrate from the SVZ to specific cortices, with the majority migrating to the prefrontal cortex,” says Vittorio Gallo, Ph.D., Director of the Center for Neuroscience Research at Children’s National, and co­-senior study author. “Of note, we revealed that the anterior SVZ is a critical source of newborn neurons destined to populate the upper layers of the cortex. We challenged this process through chronic hypoxia exposure, which severely impaired neurogenesis within the SVZ, depleting this critical source of interneurons.”

In the preclinical model of hypoxia as well as in humans, brains were smaller, weighed significantly less and had a significant reduction in cortical gray matter volume. In the prefrontal cortex, there was a significant reduction in white matter neuroblasts. Taken as a whole, according to the study authors, the findings suggest that impaired neurogenesis within the SVZ represents a cellular mechanism underlying hypoxia ­induced, region ­specific reduction in immature neurons in the cortex. The prefrontal cortex, the region of the brain that enables such functions as judgment, decision­ making and problem solving, is most impacted. Impairments in higher ­order cognitive functions involving the prefrontal cortex are common in patients with CHD.

Zhe Han, PhD

Key to genetic influence of APOL1 on chronic kidney disease

Zhe Han

Drosophila melanogaster nephrocytes share structural and functional similarities with human renal cells, making the fruit fly an ideal pre-clinical model for studying how the APOL1 gene contributes to renal disease in humans.

Using the Drosophila melanogaster pre-clinical model, a Children’s National Health System research team identified a key mechanism by which the APOL1 gene contributes to chronic kidney disease in people of African descent. The model exploits the structural and functional similarities between the fruit fly’s nephrocytes and renal cells in humans to give scientists an unprecedented ability to study gene-to-cell interactions, identify other proteins that interact with APOL1 in renal disease, and target novel therapies, according to a paper published November 18 in the Journal of the American Society of Nephrology.

“This is one of the hottest research topics in the kidney field. We are the first group to generate this result in fruit flies,” says Zhe Han, Ph.D., a senior Drosophila specialist and associate professor in the Center for Cancer & Immunology Research at Children’s National. Han, senior author of the paper, presented the study results this month during Kidney Week 2016, the American Society of Nephrology’s annual gathering in Chicago that was expected to draw more than 13,000 kidney professionals from around the world.

The advantages of Drosophila for biomedical research include its rapid generation time and an unparalleled wealth of sophisticated genetic tools to probe deeply into fundamental biological processes underlying human diseases. People of African descent frequently inherit a mutant version of the APOL1 gene that affords protection from African sleeping sickness, but is associated with a 17- to 30-fold greater chance of developing certain types of kidney disease. That risk is even higher for individuals infected with the human immunodeficiency virus (HIV). Drosophila renal cells, called nephrocytes, accurately mimic pathological features of human kidney cells during APOL1-associated renal disease.

“Nephrocytes share striking structural and functional similarities with mammalian podocytes and renal proximal tubule cells, and therefore provide us a simple model system for kidney diseases,” says Han, who has studied the fruit fly for 20 years and established the fly nephrocyte as a glomerular kidney disease model in 2013 with two research papers in the Journal of the American Society of Nephrology.

In this most recent study, Han’s team cloned a mutated APOL1 gene from podocyte cells cultured from a patient with HIV-associated nephropathy. They created transgenic flies making human APOL1 in nephrocytes and observed that initially the transgene caused increased cellular functional activity. As flies aged, however, APOL1 led to reduced cellular function, increased cell size, abnormal vesicle acidification, and accelerated cell death.

“The main functions of nephrocytes are to filter proteins and remove toxins from the fly’s blood, to reabsorb protein components, and to sequester harmful toxins. It was surprising to see that these cells first became more active and temporarily functioned at higher levels,” says Han. “The cells got bigger and stronger but, ultimately, could not sustain that enhancement. After swelling to almost twice their normal size, the cells died. Hypertrophy is the way that the human heart responds to stress overload. We think kidney cells may use the same coping mechanism.”

The Children’s research team is a multidisciplinary group with members from the Center for Cancer & Immunology Research, the Center for Genetic Medicine Research, and the Division of Nephrology. The team also characterized fly phenotypes associated with APOL1 expression that will facilitate the design and execution of powerful Drosophila genetic screening approaches to identify proteins that interact with APOL1 and contribute to disease mechanisms. Such proteins represent potential therapeutic targets. Currently, transplantation is the only option for patients with kidney disease linked to APOL1.

“This is only the beginning,” Han says. “Now, we have an ideal pre-clinical model. We plan to start testing off-the-shelf therapeutic compounds, for example different kinase inhibitors, to determine whether they block any of the steps leading to renal cell disease.”

‘Trojan horse’ macrophage TNF-alpha opens door for HIV-1 to enter kidney epithelial cells, causing nephropathy

macrophage

Like a Trojan horse, the macrophage sits atop the epithelial cell with HIV hidden inside, opening a doorway into the kidney cell for high levels of HIV-1 to enter.

When nephrologist Patricio Ray, M.D., began investigating human immunodeficiency virus (HIV) as a renal fellow, children infected with the virus had a life expectancy of no more than seven years, and kids of African descent curiously were developing a type of HIV-related kidney disease.

HIV-associated nephropathy (HIVAN) is a progressive kidney disease seen in people who are both HIV-positive and of African ancestry. Kids who carry a modified protein that protects them against sleeping sickness are 80 times more likely to develop this type of kidney disease. Due to the kidney damage, they can have abnormal amounts of protein in their urine, focal segmental glomerulosclerosis, and microcystic tubular dilation, which can lead to enlarged kidneys and chronic kidney failure.

“No one understood how HIV could affect kidney cells that lack the receptors expressed in T cells and white cells,” recalls Dr. Ray, Robert Parrott Professor of Pediatrics at Children’s National Health System. Virologists said kidney epithelial cells that lacked CD4, a major receptor where HIV attaches, could not be infected with the virus. Nephrologists, meanwhile, were seeing that HIV infection was damaging these cells.

It’s taken two decades to unravel the medical mystery, aided by urine samples he coaxed kids to donate by offering them the latest music from New Kids on the Block in exchange for each urine bottle. Many of the kids died years ago, but their immortalized cells were essential in determining, through a process of elimination, which renal cell types were capable of being infected by HIV-1.

The paper represents the capstone of Dr. Ray’s career.

“This is how difficult it is to get an important contribution in science,” he says. “It’s 20 years of work involving the excellent contributions of many people, but that’s why research is called research. In the end, it’s all a learning process. But, it’s amazing how the puzzle pieces begin to fit. When the puzzle fits, it’s good.”

Dr. Ray, in collaboration with lead author Jinliang Li, Ph.D., and four additional Children’s National co-authors, published a paper November 3 in the Journal of the American Society of Nephrology that establishes a new role for transmembrane TNF-alpha, that of a facilitator that makes it easier for the HIV virus to enter certain cell types and replicate there.  Like a Trojan horse, the macrophage sits atop the epithelial cell with HIV hidden inside, opening a doorway into the kidney cell for high levels of HIV-1 to enter.

As a starting point, the research team cultured podocytes from the urine of kids with HIVAN. Through a number of steps, they isolated the unique contributions of the HIV envelope, heparan sulfate proteoglycans as attachment receptors – the glue that binds HIV to podocytes – and the essential role played by TNF-a, a 212-amino acid long type 2 transmembrane protein, in regulating at least two processes, including viral entry and fusion. They used a fluorescent marker to tag HIV-1 viruses, so it lit up bright green. Thus primed with transmembrane TNF-a, the podocytes were susceptible to HIV-1 infection when exposed to high viral loads.

Additional research is needed, such as in vitro work to help understand how HIV traffics within the cell, Dr. Ray says. Those insights could winnow the list of existing therapies that could block key steps, such as attachment to the viral envelope, which could help all people of African descent carrying the genetic mutation, including underserved kids in sub-Saharan Africa.

Another open research question is that certain cells located in the placenta and cervix express TNF-a, and may be more likely to be infected by HIV. Blocking that process could help prevent pregnant HIV-positive mothers from transmitting illness to their offspring.

Learning platform teaches clinicians how to spot and treat malaria

Children’s National experts are outlining a novel approach to helping healthcare providers learn how to diagnose and manage malaria; the online tool provides real-time feedback about their decision making.

Children’s National experts are outlining a novel approach to helping healthcare providers learn how to diagnose and manage malaria; the online tool provides real-time feedback about their decision making.

Next-generation medical education looks like this: A white-coat wearing avatar with the voice, face, and know-how of one of the nation’s leading infectious disease experts walks you through the twists and turns of how to diagnose malaria, making stops in a variety of hospital settings. If you make the right diagnostic and treatment decisions, you get instantaneous gold stars. If your choices are off-the-mark, at each decision point you get a clear explanation of why your answer was incorrect.

“This is the future of medical education,” says Barbara Jantausch, M.D., F.A.A.P., F.I.D.S.A., an infectious disease specialist at Children’s National Health System. She’s the female avatar with the John Travolta dance moves and expertise about malaria’s epidemiology, diagnosis, and treatment.

Dr. Jantausch will present a poster, “The Hot Zone: An Online Decision-Centered Vignette Player for Teaching Clinical Diagnostic Reasoning Skills,” during IDWeek 2016, the annual meeting of the Infectious Diseases Society of America. “It’s case-based, interactive e-learning where you choose your own adventure. The beauty of this module is the training can be self-directed,” Dr. Jantausch adds.

“At Children’s National, we’re pioneering the effort to build discovery-based learning platforms,” says Jeff Sestokas, Director of eLearning. In the vignette player, he’s the male avatar named Dr. Bear. Malaria is the first infectious disease training module but others are planned for the global health series, including Chagas disease and Zika virus, Sestokas says.

Identifying the illness

According to the Centers for Disease Control & Prevention (CDC), in 2015 an estimated 214 million people around the world had malaria, a mosquito-borne illness, and 438,000 of them died. Because of the lengthy incubation period, many international travelers do not show malaria symptoms until they return to the United States and experience flu-like symptoms including high fevers, shaking chills, and dehydration. Their lab results may include metabolic acidosis, hypoglycemia, normocytic anemia, or thrombocytopenia. At Children’s, 25 percent of children admitted with travel-related malaria are admitted to the intensive care unit.

“This started as a way to offer people in areas that do not see as many patients with malaria an opportunity to learn the same critical thinking skills,” she adds.

People who click through the vignettes play the role of a clinician working in the emergency department whose patients include a 10-year-old girl who has just returned from vacation two weeks prior. The exhausted girl lies on a bed amid weeping parents and grandparents. She suffers from a headache and muscle pain and has a 39.8 C fever, though it spiked higher before her arrival at the ED.

“Because symptoms for malaria can mimic other infectious diseases, clinicians need to be able to recognize it in order to ask the most appropriate questions,” she says.

Making real-time decisions

In the vignette, participants are asked to type additional questions to help with diagnosis. Then, they select one of three geographic regions to explore in the 20-minute module in order to gain a better appreciation of the epidemiology of malaria, including the Plasmodium species that cause disease in those regions; to recognize a patient with symptoms of malaria; and to manage their care in keeping with the CDC’s guidance.

Within a few clicks, participants select the degree of the girl’s parasitemia, view slides from thick and thin blood smears, choose the medicine best suited for the parasite causing illness and geographic region the family visited, and decide on follow-up care.

“The timed sections force decision-making in real-world situations,” Sestokas adds. “Behind the scenes, we can look at how well clinicians recognize the subtleties prior to making their decisions and we provide feedback in real-time. Ultimately, our goal is to stimulate deliberate, reflective practices.”

Finding new ways to fight hemorrhagic cystitis for cancer patients

Michael Hsieh

Children diagnosed with cancer face fear and uncertainty, a series of medical appointments, and multiple diagnostic tests and treatments.

Children diagnosed with cancer face fear and uncertainty, a series of medical appointments, and multiple diagnostic tests and treatments. On top of these challenges, says Children’s National Health System urologist Michael Hsieh, M.D., Ph.D., many patients contend with additional issues: Treatment side effects, discomforts, and dangers that nearly eclipse that of the cancer itself. One of the most common side effects is hemorrhagic cystitis (HC), a problem marked by extreme inflammation in the bladder that can lead to tremendous pain and bleeding.

HC often results from administering two common chemotherapy drugs, cyclophosphamide and ifosfamide, used to treat a wide variety of pediatric cancers, including leukemias and cancers of the eye and nerves. In the United States alone, nearly 400,000 patients of all ages receive these drugs annually. Of these, up to 40 percent develop some form of HC, from symptomatic disease characterized by pain and bloody urine to cellular changes to the bladder detected by microscopic analysis.

“Having to deal with therapy complications makes the cancer ordeal so much worse for our patients,” says Dr. Hsieh, Director of the Clinic for Adolescent and Adult Pediatric Onset Urology at Children’s National. “Being able to eliminate this extremely detrimental side effect once and for all could have an enormous impact on patients at our hospital and around the world.”

Preventing complications with mesna

The severity of side effects from cyclophosphamide and ifosfamide can vary from mild and fleeting to bladder bleeding so extensive that patients require multiple transfusions and surgery to remove blood clots that can obstruct urinary release, says Dr. Hsieh, who frequently treats patients with this condition. But HC isn’t inevitable, he adds. A drug called mesna has the potential to prevent this complication when prescribed before a patient receives chemotherapy.

The problem is for a fraction of patients, mesna simply doesn’t work. For others, mesna can cause its own serious side effects, such as life-threatening malfunctions of the heart’s electrical system or allergic reactions.

“These kids are often already very sick from their cancers and treatments, and then you compound it with these complications,” says Dr. Hsieh. “There’s a desperate need for alternatives to mesna.”

Looking at alternative treatments

In a new review of the scientific literature, published August 24 by Urology, senior author Dr. Hsieh and a colleague detail all the substitutes for this drug that researchers have examined over several years.

One of these is hyperhydration, or delivering extra fluid intravenously to help flush the bladder and keep dangerous chemotherapy drug metabolites from accumulating and causing damage. Hyperhydration, however, isn’t an option for some patients with kidney, lung, or liver problems, who can’t tolerate excess fluid.

Researchers also have invested heavily in antioxidants as alternative treatments. Because much of the damage caused by these chemotherapy agents is thought to result from a cascade of oxidizing free radicals that cyclophosphamide and ifosfamide launch in the bladder, antioxidants might prevent injury by halting the free radical attack. Antioxidants that researchers have explored for this purpose include cytokines, or immune-signaling molecules, known as interleukin-1 and tumor necrosis factor, and a compound called reduced glutathione. Other studies have tested plant-based antioxidants, including a component of red wine known as resveratrol; a compound called diallyl disulfide isolated from garlic oil; and extracts from Uncaria tomentosa, a woody vine commonly known as “cat’s claw” that grows in the jungles of Central and South America.

Researchers also have tested options that focus on reducing the intense inflammation that cyclophosphamide and ifosfamide cause in the bladder, including the corticoid steroid drug dexamethasone as well as another cytokine known as interleukin-4.

However, Dr. Hsieh says, studies have shown that each of these treatments is inferior to mesna. To truly combat HC, researchers not only need to find new drugs and methods that outperform mesna but also new ways to reverse HC after other measures fail—problems he’s working to solve in his own lab.

3 ways to bring safe surgery to kids in remote regions

On Oct. 10, at the World Federation of Pediatric Surgeons (WOFAPS) Congress, in Washington, DC, the chief executives of four top North American pediatric hospitals held a candid discussion about bridging gaps in access to safe, high-quality surgical care for children everywhere. Below are three key strategies that emerged from the conversation.

1. Deploy innovative technologies

Kurt Newman, M.D., president and CEO of Children’s National Health System, kicked off Monday’s panel by describing a so-called innovation paradox. Game-changing innovations in pediatric medicine, he said, often emanate from both ends of the global development spectrum.

First-world technologies–such as telemedicine and remote robotics–developed in affluent regions are bringing important specialized care opportunities to lower-resourced communities. At the same time, pressures experienced in developing regions to adapt to challenging conditions and resource constraints can lead to creative solutions with implications well beyond the third world.

According to Michael Apkon, M.D., CEO of the Toronto-based Hospital for Sick Children, up to 85 percent of children in the developed world are cared for in emergency departments that have no specific in-house pediatric expertise. For the most part, he said, they are treated in general hospitals by physicians and nurses with no specific training in pediatric care.

In remote areas like rural Ontario, there simply isn’t enough volume to sustain in-house pediatric specialists in every hospital, Apkon explained, “but there’s a big opportunity to provide support from centers that do have that capacity.” Through telemedicine and remote robotics, “we can guide caregivers that are quite capable of doing interventions if they have the right support,” he said.

At the same time, technologies created to meet specific third-world needs are demonstrating potential for broader applications.

Dr. Newman highlighted one such technology – a low-cost, disposable, multifunctional incubator for at-risk, low-birth-weight babies – developed by the Center for Advanced Sensor Technology at University of Maryland Baltimore County. The technology won a major grant earlier this week as part of a device competition at the 4th annual Sheikh Zayed Pediatric Surgical Innovation Symposium.

Though it was developed specifically to help curb preventable deaths within the first week of birth in developing areas, the technology could have cost-reducing applications for hospitals around the world.

2. Provide training opportunities

Richard Azizkhan, MD, CEO of Children’s Hospital & Medical Center in Omaha, spent the early decades of his career working to reconstruct a functioning health care system in post-war Bosnia. A key starting point, he said, was building infrastructure for training and education.

For several years during the war, there were simply no training opportunities for in-country physicians and nurses, he explained. Working with colleagues, Azizkhan set up educational exchange programs and academic centers to teach skills in minimally invasive surgery and other modern techniques. Over time, trainees become trainers, and those skills propagated widely.

“I was training people who ultimately ended up becoming much better than I was,” said Azizkhan. “The first person I trained ended up doing more than 400 cases and becoming a leading trainer for the entire Balkans region.”

Success didn’t happen overnight. “It took literally 20 years to build that infrastructure,” he said. But today the country has capacity for very sophisticated care, including transplants and neonatal oncology.

Dr. Apkon echoed the value of training opportunities for care providers in under-resourced regions.

“Parts of the world that are blessed with the ability to have a specialized system have a moral obligation to help in whatever way they can to create capacity where it doesn’t yet exist,” he said.

Through the SickKids-Ghana Initiative, 1500 nurses in Ghana are being trained to provide very basic services in rural communities that lack a developed healthcare system. The work is aimed at training nurses in foundational elements of holistic pediatric care, including administering treatments for low oxygen, dehydration, and low blood sugar.

3. Build partnerships – locally and globally

In his former capacity at the Cleveland Clinic, Marc Harrison, MD, incoming CEO of Intermountain Healthcare, was tasked with building an entire new multispecialty hospital in Abu Dhabi.

When asked about the key to his success, Harrison didn’t hesitate.  “The biggest thing we did right was have the right partner,” he said.

Working with the Crown Prince of Abu Dhabi and many other local partners, Harrison gained insights about how health care is delivered in the region and any societal and political considerations that could impact the hospital’s operations.

“If you’re coming into a new place and are too arrogant to see that there are those who understand the environment better than you, you will fail,” he said. “It isn’t enough to have technical skills or a long track record … if you don’t have the ability to get things done on the ground, you won’t succeed.”

Dr. Azizkhan also emphasized the importance of partnerships – not just locally but globally.

In North America, he pointed out, over 100 institutions are working together to share data and best practices to improve quality and safety across systems. Ventilator-associated pneumonias, central line infections, and surgical site infections, he said, can be dramatically reduced by sharing best practices.

Dr. Newman closed the panel noting, “One thing I’ve found through my career as a surgeon,” he said, “is that the community of cooperation, friendship, and collaboration among pediatric surgeons is unparalleled.”

Spinal fusion surgical home helps kids go home sooner

scoli-1

The first of its kind for pediatric patients, the Children’s National Spinal Fusion Surgical Home implements a newly developed model of care to streamline and optimize the spinal fusion process for adolescent idiopathic scoliosis patients.

Using frameworks of care used in adult models, along with best practices and literature reviews, a multidisciplinary team developed the first Spinal Fusion Surgical Home for pediatric patients. It standardizes the infection-control process, pain-management pathway, and physical-therapy program for patients undergoing spinal fusion.

“This model eliminates variability in the care process and increases the quality of care for pediatric patients,” said Matthew Oetgen, MD, MBA, Chief of Orthopaedic Surgery and Sports Medicine. “It’s just the start—by developing this model specifically for our young patients with adolescent idiopathic scoliosis, we are paving the way for a number of other kids that require different kinds of surgeries.”

Hallmarks of the spinal fusion surgical home
From pre-operative care through recovery, the Spinal Fusion Surgical Home streamlines care with an emphasis on increasing quality outcomes for patients. Children’s National provides an informational website and a single point of contact for scheduling procedures and pre-operative laboratory exams. Before surgery, patients and families attend an evening education class that features presentations from orthopaedic nurse practitioners, physical therapists, and anesthesiologists.

After surgery, a nurse follows up by phone to assess how the patient is handling pain and healing.

Increasing the quality of care
By implementing these standardized protocols, Children’s National has seen a decrease in the average length of stay for spinal fusion patients from about five days to three and a half days. The surgical home also has reduced the transfusion rate from 30 to 12 percent, and patient pain scores have decreased.  “Patients are getting better faster with less pain, and are getting to leave the hospital sooner,” says Karen Thomson, MD.

Children’s National also is creating surgical homes for sickle cell disease patients, who need a variety of different types of surgery, as well as for children who need Nissen fundoplication and heart surgery.

Javad Nazarian

Surviving pediatric diffuse intrinsic pontine glioma

Mutations in histone-encoding genes are associated with the vast majority of pediatric DIPG cases.

For more than four decades, clinicians around the nation have been giving the parents of pediatric patients diagnosed with diffuse intrinsic pontine glioma (DIPG) the same grim prognosis. In the past five years, there has been an explosion of innovative research at Children’s National Health System and elsewhere that promises to change that narrative. That’s because the black box that is DIPG is beginning to divulge its genetic secrets. The new-found research knowledge comes as a direct result of parents donating specimens, judicious shepherding of these scarce resources by researchers, development of pre-clinical models, and financing from small foundations.

From just 12 samples six years ago, Children’s National has amassed one of the nation’s largest tumor bio banks – 3,000 specimens donated by more than 900 patients with all types of pediatric brain tumors, including DIPG.

Such donated specimens have led to the identification of H3K27M mutations, a groundbreaking finding that has been described as the single-most important discovery in DIPG. Mutations in histone-encoding genes are associated with the vast majority of pediatric DIPG cases.

Histone mutations (also referred to as oncohistones) are sustained in the tumor throughout its molecular evolution, found a research team led by Javad Nazarian, Ph.D. Not only were H3K27M mutations nearly ubiquitous in all samples studied, the driver mutation maintained partnerships with other secondary mutations as DIPG tumor cells spread throughout the developing brain. Children’s National researchers have identified tumor driver mutations and obligate partner mutations in DIPG. They are examining what happens downstream from the histone mutation – changes in the genome that indicate locations they can target in their path toward personalized medicine. The value of that genomic knowledge is akin to emergency responders being told the specific house where their help is needed, rather than a ZIP code or city name, Dr. Nazarian says. While there is currently no effective treatment for DIPG, new research has identified a growing number of genomic targets for future therapeutics.“That changed the dynamic,” says Dr. Nazarian. “In DIPG clinical research, nothing had changed for 45 years. Now we know some of the genomic mutations, how the tumor was evolving – gaining new mutations, losing mutations. With precision medicine, we can target those mutations.”

Another study led by neuro-oncologist Eugene Hwang, M.D., reported the most comprehensive phenotypic analyses comparing multiple sites in a young girl’s primary and metastatic tumors. This study showed that despite being uniform, small molecules (mRNA) could be used to distinguish an evolved tumor from its primary original tumor mass.Key to this multidisciplinary work is collaboration across divisions and departments. Within the research lab, knowledge about DIPG is expanding.

Each member of the DIPG team – neurosurgery, neuro-oncology, immunology, genomics, proteomics – feeds insight back to the rest of the team, accelerating the pace of research discoveries being translated into clinical care. Among the challenges that the team will address in the coming months is outmaneuvering tumors that outsmart T-cells (immune cells).

“What is happening in the checkpoint inhibitor field is exciting,” says Catherine M. Bollard, MBChB, MD, Chief of Allergy and Immunology and Director of the Program for Cell Enhancement of Technologies for Immunotherapy. “The inhibitors work by reversing the ‘off’ switch – releasing the brake that has been placed on the T-cells so they can again attack multiple tumor proteins. The next exciting step, and novel to Children’s National, will be to combine this approach with T-cell therapies specifically designed to attack the DIPG tumors. Unlike the use of combination chemotherapy, which has had a limited impact, we hope that the novel combination of immunotherapeutic approaches will offer the hope of a potential cure.”

Dr. Hwang, another member of the multidisciplinary team, adds: “When you’re looking at the landscape – for me, at least – it starts and ends with how my patients are doing. There are kids for whom we have had great successes in improving survival rates in some cancers, like leukemia, and some where the needle has moved nowhere, like DIPG. We’re still trying to figure out the whole picture of who responds. The immune system is present in all kids. Its ability to attack is present in all kids.”

Children’s National is one of the few hospitals in the nation that conducts brainstem biopsies for DIPG and does so with very little chance of complications. The pons is like a superhighway through which nerves pass, making it instrumental in smooth operation of such vital functions as breathing, heart rate, sleeping, and consciousness. The ability of neurosurgeon Suresh Magge, MD, to perform such sensitive biopsies upends conventional wisdom that these procedures were inherently too dangerous. Within two weeks of diagnosis, genomics analyses are run to better understand the biology of that specific tumor. Within the following weeks, the tumor board occurs, and patients with DIPG are placed on therapy that best targets their tumor’s mutations.

The black box that is diffuse intrinsic pontine glioma is beginning to divulge its genetic secrets.

Despite an increasing number of experimental therapies tested via clinical trials, more than 95 percent of children with DIPG die within two years of diagnoses. Biomarkers that point to DIPG – like the copies of DNA that tumors shed and leave behind in the bloodstream – could enable creation of liquid biopsies, compared with today’s surgical approach.

Children’s also is making a concerted effort to create preclinical models of DIPG. Preclinical models will be used to winnow the field of potential therapeutics to the candidates most likely to help children survive DIPG. The preclinical tumor cells will be labeled with luciferase – enzymes that, like photoproteins, produce bioluminescence – permitting the researcher to visually see the formation, progression, and response of DIPG tumors to treatment in preclinical settings.

These preclinical models could be used to test multiple drug combinations in conjunction with radiation therapy. Molecular signatures and response to treatment could then be assessed to learn how the tumor resists therapy. Due to the obligate partnerships between driver mutations and secondary mutations, the research team already knows that effective DIPG medicines will need more than one target. If there were a single mutation, that would be like having a single master key to open many locks. Multiple mutations imply that more than one key will be needed. Thus, the search for cures for DIPG will necessitate taking a multi-pronged approach.

Combined drug regimens, including those created with proprietary technology, with or without radiation, will be keys to targeting myriad mutations in order to kill tumors where they are. Those drug combinations that demonstrate they can do their jobs – slowing tumor growth, increasing chances of survival, taming toxicity – will be selected for clinical application.

Immunotherapy leverages T-cells, the immune system’s most able fighters, to help in the overall goal of extending patients’ survival. One of the most challenging aspects of pediatric brain tumors is the body does a very good job of shielding the brain from potential pathogens. Precise drug delivery means finding innovative ways for therapeutics to cross the blood-brain barrier in order to reach the tumor. The team has identified one such potential target, the protein NG2, which may represent a good target for immune therapy. The protein is expressed in primitive cells that have not become specialized – meaning there may be an opportunity to intervene before it is driven to become a tumor cell.

Related resources
Research at a Glance: Clinicopathology of diffuse intrinsic pontine glioma and its redefined genomic and epigenomic landscape
Research at a Glance: The role of NG2 proteoglycan in glioma
Research at a Glance: Spatial and temporal homogeneity of driver mutations in diffuse intrinsic pontine glioma
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Rheumatic heart disease is a family affair

Parasternal long axis echocardiographic still frames in early systole in black and white and color Doppler of RHD-positive index case, sibling, and mother.

Parasternal long axis echocardiographic still frames in early systole in black and white and color Doppler of RHD-positive index case, sibling, and mother.

Siblings of children in Northern Uganda with latent rheumatic heart disease (RHD) are more likely to have the disease and would benefit from targeted echocardiographic screening to detect RHD before it causes permanent damage to their heart valves, according to an unprecedented family screening study.

RHD results from a cascade of health conditions that begin with untreated group A β-hemolytic streptococcal infection. In 3 percent to 6 percent of cases, repeat strep throat can lead to acute rheumatic fever. Almost half of children who experience acute rheumatic fever later develop chronic scarring of the heart valves, RHD.  RHD affects around 33 million people and occurs most commonly in low-resource environments, thriving in conditions of poverty, poor sanitation, and limited primary healthcare. Treating streptococcal infections can prevent a large percentage of children from developing RHD, but these infections are difficult to diagnose in low-resource settings.

Right now, kids with RHD often are not identified until they reach adolescence, when the damage to their heart valves is advanced and severe cardiac symptoms or complications develop. In such countries, cardiac specialists are rare, and intervention at an advanced stage is typically too expensive or unavailable.  Echocardiographic screening can “see” RHD before symptoms develop and allow for earlier, more affordable, and more practical intervention. A team led by Children’s National Health System clinicians and researchers conducted the first-ever family echocardiographic screening study over three months to help identify optimal strategies to pinpoint the families in Northern Uganda at highest RHD risk.

“Echocardiographic screening has the potential to be a powerful public health strategy to lower the burden of RHD around the world,” says Andrea Beaton, M.D., a cardiologist at Children’s National and the study’s senior author. “Finding the 1 percent of vulnerable children who live in regions where RHD is endemic is a challenge. But detecting these silent illnesses would open the possibility of providing these children monthly penicillin shots – which cost pennies and prevent recurrent streptococcal infections, rheumatic fever, and further valve damage.”

The research team leveraged existing school-based screening data in Northern Uganda’s Gulu District and recruited 60 RHD-positive children and matched them with 67 kids attending the same schools who were similar in age and gender but did not have RHD. After screening more than 1,000 parents, guardians, and first-degree family members, they found that children with RHD were 4.5 times as likely to have a sibling who definitely had RHD.

“Definite RHD was more likely to be found in mothers, with 9.3 percent (10/107 screened) having echocardiographic evidence of definite RHD, compared to fathers 0 percent (0/48 screened, p = 0.03), and siblings 3.3 percent (10/300 screened, p = 0.02),” writes lead author Twalib Aliku, School of Medicine, Gulu University, and colleagues. “There was no increased familial, or sibling risk of RHD in the first-degree relatives of RHD-positive cases (borderline & definite RHD) versus RHD-negative cases. However, RHD-positive cases had a 4.5 times greater chance of having a sibling with definite RHD (p = 0.05) and this risk increased to 5.6 times greater chance if you limited the comparison to RHD-positive cases with definite RHD (n = 30, p = 0.03.”

The paper, “Targeted Echocardiographic Screening for Latent Rheumatic Heart Disease in Northern Uganda,” was published recently by PLoS and is among a dozen papers published this year about the group’s work in Africa, done under the aegis of the Children’s Research Institute global health initiative.

The World Health Organization previously has prioritized screening household contacts when an index case of tuberculosis (TB) is identified, the authors note. Like TB, RHD has a strong environmental component in that family members are exposed to the same poverty, overcrowding, and circulating streptococcal strains. In a country where the median age is 15.5, it is not practical to screen youths without a detailed plan, Dr. Beaton says. Additional work would need to be done to determine which tasks to shift to nurses, who are more plentiful, and how to best leverage portable, hand-held screening machines.

“Optimal implementation strategies, the who, when, in what setting, and how often to screen, have received little study to date, yet these details are critical to developing cost-effective and sustainable screening programs,” Aliku and co-authors write. “Our study suggests that siblings of children identified with latent RHD are a high-risk group, and should be prioritized for screening.”

Related resources:  Research at a Glance

Biomarkers sensitive to daily corticosteroid use

Using a mass spectrometer, Yetrib Hathout, Ph.D., is able to quantify 3,000 to 4,000 proteins from a tissue sample to identify proteins associated with cancer.

Using a Somascan proteomics assay – which simultaneously analyzes 1,129 proteins in a small volume of serum – a team led by Children’s National Health System researchers identified 21 biomarkers that respond to corticosteroids taken daily by children with Duchenne muscular dystrophy (DMD) and inflammatory bowel disease.

Corticosteroids are commonly prescribed to treat inflammatory conditions. High daily doses of corticosteroids are considered the standard of care for DMD, a type of muscular dystrophy characterized by worsening muscle weakness that affects 1 in 3,600 male infants. However, depending on the age of the child and drug dosage, chronic use is associated with such side effects as changes in bone remodeling that can lead to stunted growth, weight gain, facial puffiness caused by fat buildup, mood changes, sleep disturbances, and immune suppression. The research team sought to identify blood biomarkers that could be leveraged to create a fast, reliable way to gauge the safety and efficacy of corticosteroid use by children. The biomarkers also could guide development of a replacement therapy with fewer side effects.

“Ten pro-inflammatory proteins were elevated in untreated patients and suppressed by corticosteroids (MMP12, IL22RA2, CCL22, IGFBP2, FCER2, LY9, ITGa1/b1, LTa1/b2, ANGPT2 and FGG),” Yetrib Hathout, Ph.D., Proteomic Core Director at Children’s National, and colleagues write in the journal Scientific Reports. “These are candidate biomarkers for anti-inflammatory efficacy of corticosteroids.”

The blood biomarkers sensitive to corticosteroids fit into three broad groups, according to the authors. The children taking corticosteroids were matched with children of the same age who had never taken the medicine. Five biomarkers significantly increased in this corticosteroid-naïve group and decreased in kids prescribed corticosteroids. The biomarkers generally were inflammatory proteins and included chemokine, insulin-like growth factor binding protein 2, and integrin alpha-I/beta-1 complex.

The second group of biomarkers included nine proteins associated with macrophage and T-lymphocytes that were significantly reduced in concentration in kids taking corticosteroids. According to the study, this finding hints at corticosteroids blunting the ability of the immune system’s most able fighters to respond to infection.

In the third group were five proteins that were significantly increased by corticosteroid treatment in DMD and included matrix metalloproteinase 3, carnosine dipeptidase 1, angiotensinogen, growth hormone binding protein, insulin, and leptin, a hormone linked to appetite.

What researchers learned with this study will help them more accurately design the next phase of the work, Hathout says.

“We are the first team to report a number of novel discoveries, including that growth hormone binding protein (GHBP) levels increase with corticosteroid use. This represents a candidate biomarker for stunted growth. In order to use that new information effectively in drug development, the next studies must corroborate the role of serum GHBP levels as predictors of diminished stature,” he adds. “The study finding that four adrenal steroid hormones are depressed in kids taking corticosteroids raises additional questions about the broader impact of adrenal insufficiency, including its role in the delay of the onset of puberty.”

This work was supported by National Institutes of Health grants (R01AR062380, R01AR061875, P50AR060836, U54HD071601, K99HL130035, and R44NS095423) and Department of Defense CDMRP program grant W81XWH-15-1-0265. Additional support was provided by AFM-Telethon (18259) and the Muscular Dystrophy Association USA (MDA353094).

In Brief- Fetal Medicine

Cognitive training exercises at home help kids with sickle cell boost visuospatial working memory

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost working memory in children who suffer from sickle cell disease.

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost working memory in children who suffer from sickle cell disease.

Youths with sickle cell disease who used hand-held computers to play game-like exercises that get harder as a user’s skill level rises improved their visuospatial working memory (WM). Children with sickle cell disease, however, completed fewer training sessions during an initial study compared with children with other disease-related WM deficits.

A team led by Children’s National Health System clinicians and research scientists attempted to identify novel approaches to boost WM in children who suffer from sickle cell disease. Kids who have this red blood cell disorder inherit abnormal hemoglobin genes from each parent. Rather than slipping through large and small vessels to ferry oxygen throughout the body, their stiff, sickle-shaped red blood cells stick to vessel walls, impeding blood supply and triggering sudden pain. Children with sickle cell disease have more difficulty completing tasks that place demands on one’s WM, the brain function responsible for temporarily remembering information and manipulating that information to facilitate learning and reasoning. As a result, they’re more likely to repeat a grade, require special academic services, and to have difficulty maintaining employment as adults.

Because computerized cognitive training programs have been used with success to boost WM for children with other health conditions, such as childhood cancer, the research team sought to examine the feasibility of using the technique for kids with sickle cell disease. “This small study highlights the challenges and opportunities of implementing a home-based cognitive training intervention with youths who have sickle cell disease,” says Steven J. Hardy, PhD, a pediatric psychologist in the Divisions of Hematology, Oncology, and Blood and Marrow Transplantation at Children’s National. “While a larger, randomized controlled clinical trial is needed to better characterize efficacy, our initial work indicates that Cogmed is acceptable and moderately feasible in this population.”

Children’s National is home to the Sickle Cell Disease (SCD) Program, one of the nation’s largest, most comprehensive pediatric programs that cares for 1,350 patients younger than 21 annually. Over 15 months, the team recruited youths aged 7 to 16 participating in the program who had an intelligence quotient of at least 70 and an absolute or relative memory deficit. Those who lacked access to a tablet computer were loaned an iPad Mini 2 loaded with Cogmed RM, an interactive audiovisual cognitive training program that consists of exercises that get progressively more challenging. A clinical psychologist provided coaching and moral support through weekly telephone calls to review progress and challenges, and to offer tips on how to optimize the youths’ progress.

Six of 12 eligible participants – all girls – completed by finishing at least 20 sessions of the program. The mean number of sessions completed was 15.83, and the kids spent a median of 725 minutes working actively on Cogmed exercises. “Participants who completed Cogmed indicated that they perceived greater levels of social support from teachers,” Hardy and colleagues write in the study, published by Pediatric Blood & Cancer. “[T]here was not a statistical difference in perceived parent support.”

Among those children who completed Cogmed, standard scores increased an average of 5.05 on a measure of visuospatial short-term memory, 19.72 on a measure of verbal WM, 27.53 on a measure of visuospatial short-term memory, and 23.82 on a measure of visuospatial WM. The researchers also observed a normalizing of memory functioning for those who finished Cogmed, as a significant portion of participants scored below the average range before using Cogmed and most scored in the average range or higher on memory tests after finishing the program.

“In this initial feasibility trial, adherence to Cogmed was lower than expected (50 percent completion) compared to adherence rates of other samples of children with medical histories, including patients with symptomatic epilepsy and youth treated for cancer,” Hardy and co-authors write. “Thus, additional modifications may be needed to achieve consistent delivery of the intervention to youth with SCD.”

Related Resources: Research at a Glance

Sharp images key to spotting the earliest signs of compromised pregnancies

Fetuses wiggle. They waggle. Some pirouette within the womb, amniotic fluid easing their spins. Pregnant mothers’ meals and beverages from hours earlier wend their way through their digestive systems. On top of that, mother and offspring may breathe out of sync and their hearts may beat in time to different drummers.

In short, there’s a whole lot of movement going on in the womb.

As anyone trying to capture a photograph with a digital camera knows, sudden movements are the enemy of a sharp image. The challenge is the same for fetal researchers aiming to capture crisp functional magnetic resonance imaging (fMRI) of the developing brains of fetuses who are always on the move.

Over two years, a Children’s National Health System research team led by Wonsang You, a research associate in the Developing Brain Research Laboratory, worked out complex mathematical algorithms to account for independent fetal and placental motions, to erase those noise artifacts, and to validate the accuracy of the technique.

“[M]otion correction is optimized to the experimental paradigm, and it is performed separately in each phase as well as in each region of interest (ROI), recognizing that each phase and organ experiences different types of motion. To obtain the averaged [blood oxygen level-dependent] BOLD signals for each ROI, both misaligned volumes and noisy voxels are automatically detected and excluded, and the missing data are then imputed by statistical estimation based on local polynomial smoothing,” You and colleagues wrote in a technical article published recently by the Journal of Medical Imaging and spotlighted on the journal’s website as a featured article.

To underscore the work’s clinical utility, they analyzed differences in fetal motion by acquiring BOLD fMRI data from eight pregnant women with healthy fetuses and comparing them with eight women whose fetuses had been diagnosed with congenital heart disease (CHD) between 25 to 40 weeks of gestational age. The team focused on changes in oxygenation of the fetal brain and placenta during maternal hyperoxia, an oxygen challenge test during which both groups of pregnant women received 100 percent oxygen via face mask for four to six minutes. Measurements were then taken to determine whether there were differences in how the fetuses and the placentas responded to the oxygen challenge test.

Recognizing compromised fetuses in utero – and understanding the subtle but important ways they deviate from the trajectory of normal fetuses – opens a critical window of opportunity to intervene through nutritional, pharmaceutical, or surgical means – before brain injury is consolidated, says Catherine Limperopoulos, PhD, Director, MRI Research of the Developing Brain at Children’s National, and the paper’s senior author.“

Our goal is to exploit the power of MRI, a non-invasive imaging technique, to detect the earliest signs of the fetus getting into trouble before it runs into serious problems,” Limperopoulos says. “We needed the technical development described in this foundational work to allow us to reliably measure the fMRI BOLD response in the fetal brain and placenta.”

The BOLD signal can be degraded by the independent and collective movements of the mother and fetus. Traditional motion correction makes assumptions, such as treating all moving objects like the fetal brain, which is solid, rigid, and has a high range of motion. The traditional approach also fails to account for such subtleties as the placenta’s low range of motion and its flexing in response to maternal and fetal movements.

The research team employed four-step pre-processing – which included correcting bias magnetic field, correcting for global and local motion, and rejecting outliers – and followed with data imputation, an alphabet soup of letters and Latin symbols that mathematically accounts for objects (placenta and fetal brain) that move independently.“

We showed that the proposed preprocessing pipeline can be effectively employed to characterize fetal motion in healthy controls and CHD fetuses. Our preliminary data suggest that the degree of fetal motion tends to increase during hyperoxia in CHD fetuses (but not significantly). In addition, the motion of the fetal brain in CHD cases showed higher variance during hyperoxia compare[d] to controls,” You and colleagues write. “These observations suggest that the CHD fetus may be more responsive to maternal hyperoxia. However, these pilot data need to be validated on a larger cohort of healthy and high-risk CHD fetuses.”

Related resources: Research at a Glance