NIH funding to improve devices and safeguard cardiovascular health

Nearly 15 million blood transfusions are performed each year in the U.S., and pediatric patients alone receive roughly 425,000 transfused units. Endocrine-disrupting chemicals, such as bisphenol A and di-2-ethylhexyl-phthalate (DEHP), can leach from some plastic devices used in such transfusions. However, it remains unclear how many complications following a transfusion can be attributed to the interplay between local and systemic reactions to these chemical contaminants.


Top: Live, excised heart that is being perfused with a crystalloid buffer via the aorta. The heart is stained with a voltage-sensitive fluorescent dye, which is excited by an LED light source. Bottom, right: Cardiac action potentials are optically mapped across the epicardial surface in real-time by monitoring changes in the fluorescence signal that are proportional to changes in transmembrane voltage. Bottom, left: An activation map (middle) depicts the speed of electrical conduction across the heart surface. Credit: Rafael Jaimes, Ph.D.; Luther Swift, Ph.D.; Manelle Ramadan, B.S.; Bryan Siegel, M.D.; James Hiebert, B.S., all of Children’s National Health System; and Daniel McInerney, student at The George Washington University.

The National Heart, Lung and Blood Institute within the National Institutes of Health has awarded a $3.4 million, five-year grant to Nikki Gillum Posnack, Ph.D., assistant professor at the Sheikh Zayed Institute for Pediatric Surgical Innovation (SZI) at Children’s National Health System, to answer that question and to provide insights that could accelerate development of safer biomaterials.

According to the Food and Drug Administration, patients who are undergoing IV therapy, blood transfusion, cardiopulmonary bypass or extracorporeal membrane oxygenation or who receive nutrition through feeding support tubes have the potential to be exposed to DEHP.

Posnack led a recent study that found that an experimental model exposed to DEHP experienced altered autonomic regulation, heart rate variability and cardiovascular reactivity and reported the findings Nov. 6, 2017, in the American Journal of Physiology. The pre-clinical model study is the first to show such an association between phthalate chemicals used in everyday medical devices like IV tubing and cardiovascular health.

In the follow-on research, Posnack and colleagues will:

  • Use in vivo and whole heart models to define the extent to which biomaterial leaching and chemical exposure alters cardiovascular and autonomic function in experimental models
  • Determine whether biocompatibility and incidental chemical exposure are linked to cardiovascular and autonomic abnormalities experienced by pediatric patients post transfusion
  • Compare and contrast alternative biomaterials, chemicals and manufacturing techniques to identify safer transfusion device options.

“Ultimately, we hope to strengthen the evidence base used to inform decisions by the scientific, medical and regulatory communities about whether chemical additives that have endocrine-disrupting properties should be used to manufacture medical devices,” Posnack says. “Our findings also will highlight incentives that could accelerate development of alternative biomaterials, additives and fabrication techniques to improve safety for patients undergoing transfusion.”

Nobuyuki Ishibashi

Children’s receives NIH grant to study use of stem cells in healing CHD brain damage

Nobuyuki Ishibashi

“Bone marrow stem cells are used widely for stroke patients, for heart attack patients and for those with developmental diseases,” explains Nobuyuki Ishibashi, M.D. “But they’ve never been used to treat the brains of infants with congenital heart disease. That’s why we are trying to understand how well this system might work for our patient population.”

The National Institutes of Health (NIH) awarded researchers at Children’s National Health System $2.6 million to expand their studies into whether human stem cells could someday treat and even reverse neurological damage in infants born with congenital heart disease (CHD).

Researchers estimate that 1.3 million infants are born each year with CHD, making it the most common major birth defect. Over the past 30 years, advances in medical technology and surgical practices have dramatically decreased the percentage of infants who die from CHD – from a staggering rate of nearly 100 percent just a few decades ago to the current mortality rate of less than 10 percent.

The increased survival rate comes with new challenges: Children with complex CHD are increasingly diagnosed with significant neurodevelopmental delay or impairment. Clinical studies demonstrate that CHD can reduce oxygen delivery to the brain, a condition known as hypoxia, which can severely impair brain development in fetuses and newborns whose brains are developing rapidly.

Nobuyuki Ishibashi, M.D., the study’s lead investigator with the Center for Neuroscience Research and director of the Cardiac Surgery Research Laboratory at Children’s National, proposes transfusing human stem cells in experimental models through the cardio-pulmonary bypass machine used during cardiac surgery.

“These cells can then identify the injury sites,” says Dr. Ishibashi. “Once these cells arrive at the injury site, they communicate with endogenous tissues, taking on the abilities of the damaged neurons or glia cells they are replacing.”

“Bone marrow stem cells are used widely for stroke patients, for heart attack patients and for those with developmental diseases,” adds Dr. Ishibashi. “But they’ve never been used to treat the brains of infants with congenital heart disease. That’s why we are trying to understand how well this system might work for our patient population.”

Dr. Ishibashi says the research team will focus on three areas during their four-year study – whether the stem cells:

  • Reduce neurological inflammation,
  • Reverse or halt injury to the brain’s white matter and
  • Help promote neurogenesis in the subventricular zone, the largest niche in the brain for creating the neural stem/progenitor cells leading to cortical growth in the developing brain.

At the conclusion of the research study, Dr. Ishibashi says the hope is to develop robust data so that someday an effective treatment will be available and lasting neurological damage in infants with congenital heart disease will become a thing of the past.

Lisa M. Guay-Woodford, M.D

Internationally renowned pediatric nephrologist named to NIH advisory council

Lisa M. Guay-Woodford, M.D

Pediatric nephrologist Lisa M. Guay-Woodford, M.D., has been named to a three-year term as adviser serving on the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Kidney, Urologic and Hematologic Diseases subcouncil.

Dr. Guay-Woodford, Director of the Center for Translational Science at Children’s National, is an internationally recognized expert in the mechanisms that modulate the clinical severity of certain inherited renal disorders, such as autosomal recessive polycystic kidney disease. She holds the Richard L. and Agnes F. Hudson Professorship in Health Services Research at Children’s National.

NIDDK, like other grant-awarding institutes within the National Institutes of Health (NIH), looks to its advisory councils for feedback on procedures that govern staff and manage its grant portfolios. The institute, the fifth largest at the NIH, supports clinical research about internal medicine and related subspecialties for many of the most common chronic health conditions.

“It is a tremendous honor to be asked to serve on this important council. I look forward to providing advice and perspective on the exciting portfolio of NIDDK-funded projects,” Dr. Guay-Woodford says.

Javad Nazarian

Advancing pediatric cancer research by easing access to data

Javad Nazarian

“This is a tremendous opportunity for children and families whose lives have been forever altered by pediatric cancers,” says Javad Nazarian, Ph.D., M.S.C., principal investigator in the Center for Genetic Medicine Research and scientific director of the Brain Tumor Institute at Children’s National.

Speeding research into pediatric cancers and other diseases relies not only on collecting good data, but making them accessible to research teams around the world to analyze and build on. Both efforts take time, hard work and a significant amount of financial resources – the latter which can often be difficult to attain.

In a move that could considerably advance the field of pediatric cancer, the National Institutes of Health (NIH), a body that funds biomedical research in the United States, recently awarded a public-private research collective that includes Children’s National Health System up to $14.8 million to launch a data resource center for cancer researchers around the world in order to accelerate the discovery of novel treatments for childhood tumors. Contingent on available funds, five years of funding will be provided by the NIH Common Fund Gabriella Miller Kids First Pediatric Research Program, named after Gabriella Miller, a 10-year-old child treated at Children’s National.

As principal investigators, researchers at Children’s Hospital of Philadelphia will lead the joint effort to build out the “Kids First” Data Resource Center. Children’s National in Washington, D.C., will spearhead specific projects, including the Open DIPG project, and as project ambassador will cultivate additional partnerships with public and private foundations and related research consortia to expand a growing trove of data about pediatric cancers and birth defects.

“This is a tremendous opportunity for children and families whose lives have been forever altered by pediatric cancers,” says Javad Nazarian, Ph.D., M.S.C., principal investigator in the Center for Genetic Medicine Research and scientific director of the Brain Tumor Institute at Children’s National. “From just a dozen samples seven years ago, Children’s National has amassed one of the nation’s largest tumor biorepositories funded, in large part, by small foundations. Meanwhile, research teams have been sequencing data from samples here and around the world. With this infusion of federal funding, we are poised to turn these data into insights and to translate those research findings into effective treatments.”

Today’s NIH grant builds on previous funding that Congress provided to the NIH Common Fund to underwrite research into structural birth defects and pediatric cancers. In the first phase, so-called X01 grantees—including Eric Vilain, M.D., Ph.D., newly named director of the Center for Genetic Medicine Research at Children’s National—received funding to sequence genetic data from thousands of patients and families affected by childhood cancer and structural birth defects.

This new phase of funding is aimed at opening access to those genetic sequences to a broader group of investigators around the globe by making hard-to-access data easily available on the cloud. The first project funded will be Open DIPG, run by Nazarian, a single disease prototype demonstrating how the new data resource center would work for multiple ailments.

DIPG stands for diffuse intrinsic pontine glioma, aggressive pediatric brain tumors that defy treatment and are almost always fatal. Just as crowd sourcing can unleash the collective brainpower of a large group to untangle a problem swiftly, open data sharing could accomplish the same for childhood cancers, including DIPG. In addition to teasing out molecular alterations responsible for making such cancers particularly lethal, pooling data that now sits in silos could help to identify beneficial mutations that allow some children to survive months or years longer than others.

“It’s a question of numbers,” Dr. Vilain says. “The bottom line is that making sense of the genomic information is significantly increased by working through large consortia because they provide access to many more patients with the disease. What is complicated about genetics is we all have genetic variations. The challenge we face is teasing apart regular genetic variations from those genetic variations that actually cause childhood cancers, including DIPG.”

Nazarian predicts some of the early steps for the research consortium will be deciding nuts-and-bolts questions faced by such a start-up venture, such as the best methods to provide data access, corralling the resources needed to store massive amounts of data, and providing data access and cross correlation.

“One of the major challenges that the data resource center will face is to rapidly establish physical data storage space to store all of the data,” Nazarian says. “We’re talking about several petabytes—1,000 terabytes— of data. The second challenge to address will be data dissemination and, specifically, correlation of data across platforms representing different molecular profiles (genome versus proteome, for example). This is just the beginning, and it is fantastic to see a combination of public and private resources in answering these challenges.”

Zhe Han, PhD

Lab led by Zhe Han, Ph.D., receives $1.75 million from NIH

Zhe Han, PhD

A new four-year NIH grant will enable Zhe Han, Ph.D., to carry out the latest stage in the detective work to determine how histone-modifying genes regulate heart development and the molecular mechanisms of congenital heart disease caused by these genetic mutations.

The National Institutes of Health (NIH) has awarded $1.75 million to a research lab led by Zhe Han, Ph.D., principal investigator and associate professor in the Center for Genetic Medicine Research, in order to build models of congenital heart disease (CHD) that are tailored to the unique genetic sequences of individual patients.

Han was the first researcher to create a Drosophila melanogaster model to efficiently study genes involved in CHD, the No.1 birth defect experienced by newborns, based on sequencing data from patients with the heart condition. While surgery can fix more than 90 percent of such heart defects, an ongoing challenge is how to contend with the remaining cases since mutations of a vast array of genes could trigger any individual CHD case.

In a landmark paper published in 2013 in the journal Nature, five different institutions sequenced the genomes of more than 300 patients with CHD and their families, identifying 200 mutated genes of interest.

“Even though mutations of these genes were identified from patients with CHD, these genes cannot be called ‘CHD genes’ since we had no in vivo evidence to demonstrate these genes are involved in heart development,” Han says. “A key question to be answered: How do we efficiently test a large number of candidate disease genes in an experimental model system?”

In early 2017, Han published a paper in Elife providing the answer to that lingering question. By silencing genes in a fly model of human CHD, the research team confirmed which genes play important roles in development. The largest group of genes that were validated in Han’s study were histone-modifying genes. (DNA winds around the histone protein, like thread wrapped around a spool, to become packed into a higher-level structure.)

The new four-year NIH grant will enable Han to carry out the next stage of the detective work to determine precisely how histone-modifying genes regulate heart development. In order to do so, his group will silence the function of histone-modifying genes one by one, to study their function in the fly heart development and to identify the key histone-modifying genes for heart development. And because patients with CHD can have more than one mutated gene, he will silence multiple genes simultaneously to determine how those genes work in partnership to cause heart development to go awry.

By the end of the four-year research project, Han hopes to be able to identify all of the histone-modified genes that play pivotal roles in development of the heart in order to use those genes to tailor make personalized fly models corresponding to individual patient’s genetic makeup.

Parents with mutations linked to CHD are likely to pass heart disease risk to the next generation. One day, those parents could have an opportunity to sequence their genes to learn the degree of CHD risk their offspring face.

“Funding this type of basic research enables us to understand which genes are important for heart development and how. With this knowledge, in the near future we could predict the chances of a baby being born with CHD, and cure it by using gene-editing approaches to prevent passing disease to the next generation,” Han says.

Sarah Mulkey receives NIH career development grant

Sarah Mulkey

Sarah B. Mulkey, M.D., Ph.D., a fetal-neonatal neurologist in the Division of Fetal and Translational Medicine at Children’s National Health System, has received a KL2 award from the Clinical and Translational Science Institute at Children’s National, which is funded through the National Institutes of Health. This grant, totaling $135,000 over two years, will allow Dr. Mulkey to reserve dedicated research time — apart from her clinical duties — to pursue a research project studying the autonomic nervous system in newborns.

Dr. Mulkey’s project will focus on developing a better understanding of this part of the nervous system — responsible for unconscious control of basic bodily functions, such as heart rate and breathing — in healthy, full-term babies, and how this system integrates with other brain regions responsible for mood and stress responses. Dr. Mulkey and colleagues then will compare these findings to those from babies whose autonomic nervous systems might have abnormal development, such as infants born pre-term or those with congenital heart defects or intrauterine growth restriction. The findings could help researchers develop new interventions to optimize autonomic nervous system development in vulnerable patients and improve long-term neurologic and psychological health in children.

“This award is an incredible opportunity for a young investigator since it provides protected time both for research and career development,” Dr. Mulkey says. “We need more clinicians in pediatric research to improve medical care and outcomes for children. This award makes it possible for me to devote significant time to research in order to contribute to new knowledge about babies throughout my career.”

To that end, NIH’s National Center for Advancing Translational Sciences has created a new LinkedIn page to highlight the innovative work of KL2 scholars.