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Fighting lymphoma with targeted T-cells

August 28, 2019

The Epstein-Barr virus (EBV) is best known as the cause of mononucleosis, the ubiquitous “kissing disease” that most people contract at some point in their life. But in rare instances, this virus plays a more sinister role as the impetus of lymphomas, cancers that affect the white blood cells known as lymphocytes. EBV-associated lymphomas account for about 40% of Hodgkin lymphomas, 20% of diffuse large B-cell lymphomas, and more than 90% of natural killer/T-cell lymphomas. This latter type of lymphoma typically has a very poor prognosis even with the “standard of care” lymphoma treatments such as chemotherapy and/or radiation.

When these interventions fail, the only curative approach is an allogeneic hematopoietic stem cell transplant from a healthy donor, a treatment that’s tough on patients’ bodies and carries significant risks, says Lauren P. McLaughlin, M.D., a pediatrician specializing in hematology and oncology at Children’s National in Washington, D.C. Patients who receive these allogenic transplants are immune-compromised until the donor cells engraft; the grafts can attack patients’ healthy cells in a phenomenon called graft versus host disease; and if patients relapse or don’t respond to this treatment, few options remain.

To help improve outcomes, Dr. McLaughlin and colleagues tested an addition to the allogeneic hematopoietic stem cell transplant procedure for patients with EBV-associated lymphomas: infusion of a type of immune cell called T cells specifically trained to fight cells infected with EBV.

Dr. McLaughlin, along with Senior Author Catherine M. Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research and the Program for Cell Enhancement and Technologies for Immunotherapy at Children’s National, and colleagues tested this therapy in 26 patients treated at Children’s National or Baylor College of Medicine. They published these results online on Sept. 27, 2018, in the journal Blood. The study was a Phase I clinical trial, meaning that the therapy was tested primarily for safety, with efficacy as a secondary aim.

Seven patients who received the therapy had active disease that had not responded to conventional therapies. The other 19 were patients deemed to be at high risk for relapse.

Before each patient received their stem cell transplant, their donors gave an additional blood sample to generate the cancer-fighting T cells. Over the next 8 to 10 weeks, the researchers painstakingly manufactured the immune cells known as T-cells that specifically targeted EBV, growing these cells into numbers large enough for clinical use. Then, as early as 30 days after transplant, the researchers infused these T-cells into patients administering at least two doses, spaced two weeks apart.

Over the next several weeks, the researchers at CNMC and Baylor College of Medicine monitored patients with comprehensive exams to see how they fared after these transplants. The results showed that adverse effects from the treatment were exceedingly rare. There were no immediate infusion-related toxicities to the T-cell therapy and only one incident of dose-limiting toxicity.

This therapy may be efficacious, depending on the individual patients’ circumstances, Dr McLaughlin adds. For those in complete remission but at high risk of relapsing, the two-year survival rate was 78%, suggesting that the administration of this novel T-cell therapy may give the immune system a boost to prevent the lymphoma from returning after transplant. For patients with active T-cell lymphomas, two-year survival rates were 60%. However, even these lower rates are better than the historical norm of 30-50%, suggesting that the targeted T-cell therapies could help fight disease in patients with this poor prognosis lymphoma.

Dr. McLaughlin, the study’s lead author and a Lymphoma Research Foundation grantee, notes that researchers have more work to do before this treatment becomes mainstream. For example, this treatment will need to be tested in larger populations of patients with EBV-related lymphoma to determine who would derive the most benefit, the ideal dose and dose timing. It also may be possible to extend targeted T-cell treatments like this to other types of cancers. In the future, Dr. McLaughlin adds, it may be possible to develop T-cells that could be used “off the shelf”—in other words, they wouldn’t need to come from a matched donor and would be ready to use whenever a recipient needs them. Another future goal is using this therapy as one of the first lines of treatment rather than as a last resort.

“Our ultimate goal is to find a way to avoid chemotherapy and/or radiation therapy while still effectively treating a patient’s cancer,” she says. “Can you use the immune system to do that job? We’re working to answer that question.”

In addition to Drs. McLaughlin and Bollard, study co-authors include Rayne Rouce, Stephen Gottschalk, Vicky Torrano, George Carrum, Andrea M. Marcogliese, Bambi Grilley, Adrian P. Gee, Malcolm K. Brenner, Cliona M. Rooney and Helen E. Heslop, all of Baylor College of Medicine; Meng-Fen Wu from the Dan L. Duncan Comprehensive Cancer Center; and Fahmida Hoq and Patrick J. Hanley, Ph.D. from Children’s National in Washington, D.C.

Experimental fertility preservation provides hope for young men

May 24, 2019

Confirming the presence of germ cells in testicular tissues obtained from patients. Undifferentiated embryonic cell transcription factor 1 (UTF1) is an established marker of undifferentiated spermatogonia as well as the pan-germ cell marker DEAD-box helicase 4 (DDX4). UTF1 (green) and/or DDX4 (red) immunostaining was confirmed in 132 out of 137 patient tissues available for research, including patients who had received previous non-alkylating (B, E, H, K) or alkylating (C, F, I, L) chemotherapy treatment. © The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Testicular tissue samples obtained from 189 males who were facing procedures that could imperil fertility were cryopreserved at one university, proving the feasibility of centralized processing and freezing of testicular tissue obtained from academic medical centers, including Children’s National, scattered around the world.

“It’s not surprising that the University of Pittsburgh would record the highest number of samples over the eight-year period (51 patients), given its role as the central processing facility for our recruiting network of academic medical centers,” says Michael Hsieh, M.D., Ph.D., director of transitional urology at Children’s National. “Children’s National recruited the third-highest number of patients, which really speaks to the level of collaboration I have with Jeff Dome’s team and their commitment to thinking about the whole patient and longer-term issues like fertility.”

An estimated 2,000 U.S. boys and young men each year receive treatments or have cancers or blood disorders that place them at risk for infertility. While older youths who have undergone puberty can bank their sperm prior to undergoing sterilizing doses of chemotherapy or radiation, there have been scant fertility preservation options for younger boys. However, some older adolescents and young men are too sick or stressed to bank sperm. For patients with no sperm to bank or who are too sick or stressed to bank sperm, the experimental procedure of freezing testicular tissue in anticipation that future cell- or tissue-based therapies can generate sperm is the only option.

Recent research in experimental models indicates that such testicular tissue biopsies contain stem cells, blank slate cells, hinting at the potential of generating sperm from biopsied tissue.

“This study demonstrates that undifferentiated stem and progenitor spermatogonia may be recovered from the testicular tissues of patients who are in the early stages of their treatment and have not yet received an ablative dose of therapy. The function of these spermatogonia was not tested,” writes lead author Hanna Valli-Pulaski, Ph.D., research assistant professor at the University of Pittsburgh, and colleagues in a study published online May 21, 2019, in Human Reproduction.

Right now, hematologists and oncologists discuss future treatment options with patients and families, as well as possible long-term side effects, including infertility. At Children’s National, they also mention the ongoing fertility preservation study and encourage families to speak with Dr. Hsieh. He meets with families, explains the study goals – which include determining better ways to freeze and thaw tissue and separating malignant cells from normal cells – what’s known about experimental fertility preservation and what remains unknown. Roughly half of patients decide to enroll.

“This study is unique in that there is definitely a potential direct patient benefit,” Dr. Hsieh adds. “One of the reasons the study is compelling is that it presents a message of hope to the families. It’s a message of survivorship: We’re optimistic we can help your child get through this and think about long-term issues, like having their own families.”

In this phase of the study, testicular tissue was collected from centers in the U.S. and Israel from January 2011 to November 2018 and cryopreserved. Patients designated 25% of the tissue sample to be used for the research study; 75 percent remains stored in liquid nitrogen at temperatures close to absolute zero for the patient’s future use. The fertility preservation patients ranged from 5 months old to 34 years old, with an average age of 7.9 years.

Thirty-nine percent of patients had started medical treatment prior requesting fertility preservation. Sixteen percent received non-alkylating chemotherapy while 23% received alkylating chemotherapy, which directly damages the DNA of cancer cells.

The research team found that the number of undifferentiated spermatogonia per seminiferous tubule increase steadily with age until about age 11, then rise sharply.

“We recommend that all patients be counseled and referred for fertility preservation before beginning medical treatments known to cause infertility. Because the decision to participate may be delayed, it is encouraging that we were able to recover undifferentiated spermatogonia from the testes of patients already in the early stages of chemotherapy treatments,” Dr. Hsieh says.

In addition to Dr. Hsieh, study co-authors include lead author, H. Valli-Pulaski, K.A. Peters, K. Gassei, S.R. Steimer, M. Sukhwani, B.P. Hermann, L. Dwomor, S. David, A.P. Fayomi, S.K. Munyoki, T. Chu, R. Chaudhry, G.M. Cannon, P.J. Fox, T.M. Jaffe, J.S. Sanfilippo, M.N. Menke and senior author, K.E. Orwig, all of University of Pittsburgh; E. Lunenfeld, M. Abofoul-Azab and M. Huleihel, Ben-Gurion University of the Negev; L.S. Sender, J. Messina and L.M. Klimpel, CHOC Children’s Hospital; Y. Gosiengfiao, and E.E. Rowell, Ann & Robert H. Lurie Children’s Hospital of Chicago; C.F. Granberg, Mayo Clinic; P.P. Reddy, Cincinnati Children’s Hospital Medical Center; and J.I. Sandlow, Medical College of Wisconsin.

Financial support for the research covered in this post was provided by Eunice Kennedy Shriver National Institute for Child Health and Human Development under awards HD061289 and HD092084; Scaife Foundation; Richard King Mellon Foundation; University of Pittsburgh Medical Center; United States-Israel Binational Science Foundation and Kahn Foundation.

Helpful, hopeful news for bone marrow transplant patients

February 27, 2018

Research published online Dec. 13, 2017, by The Lancet Haematology and co-led by Kirsten M. Williams, M.D., suggests that a new imaging agent can safely show engraftment as early as days after transplant – giving a helpful and hopeful preview to patients and their doctors.

Leukemia can be a terrifying diagnosis for the more than 60,000 U.S. patients who are told they have this blood cancer every year. But the treatment for this disease can be just as frightening. For patients with certain forms of leukemia, the only chance they have for a cure is to receive a massive dose of radiation and chemotherapy that kills their hematopoietic stem cells (HSCs), the cells responsible for making new blood, and then receive new HSCs from a healthy donor.

While patients are waiting for these new cells to go to the bone marrow factory and begin churning out new blood cells, patients are left without an immune system. Devoid of working HSCs for two to four weeks – or longer, if a first transplant doesn’t take – patients are vulnerable to infections that can be just as deadly as their original cancer diagnosis.

As they wait in the protected confines of a hospital, patients who undergo HSC transplants receive blood tests every day to gauge successful engraftment, searching for the presence of immune cells called neutrophils, explains Kirsten M. Williams, M.D., blood and bone marrow transplant specialist at Children’s National Health System.

“As you head into week three post-transplant and a patient’s cell counts remain at zero, everyone starts to get nervous,” Dr. Williams says. The longer a patient goes without an immune system, the higher the chance that they’ll develop a life-threatening infection. Until recently, Dr. Williams says, there has been no way beyond those daily blood tests to assess whether the newly infused cells have survived and started to grow early healthy cells in the bone marrow, a process called engraftment.

A new study could change that paradigm. Research published online Dec. 13, 2017, by The Lancet Haematology and co-led by Dr. Williams suggests that a new imaging agent can safely show engraftment as early as days after transplant – giving a helpful and hopeful preview to patients and their doctors.

The study evaluated an investigational imaging test called 18F-fluorothymidine (¹⁸F-FLT). It’s a radio-labeled analogue of thymidine, a natural component of DNA. Studies have shown that this compound is incorporated into just three white blood cell types, including HSCs. Because it’s radioactive, it can be seen on various types of common clinical imaging exams, such as positron emission tomography (PET) and computed tomography (CT) scans. Thus, after infusion, the newly infused developing immune system and marrow is readily visible.

To see whether this compound can readily and safely visualize transplanted HSCs, Dr. Williams and colleagues tested it on 23 patients with various forms of high-risk leukemia.

After these patients received total-body irradiation to destroy their own HSCs, they received donor HSCs from relatives or strangers. One day before they were infused with these donor cells, and then at five or nine days, 28 days, and one year after transplantation, the patients underwent imaging with the novel PET/and CT scan imaging platform.

Each of these patients had successful engraftment, reflected in blood tests two to four weeks after their HSC transplants. However, the results of the imaging exams revealed a far more complicated and robust story.

With ¹⁸F-FLT clearly visible in the scans, the researchers saw that the cells took a complex journey as they engrafted. First, they migrated to the patients’ livers and spleens. Next, they went to the thoracic spine, the axial spine, the sternum, and the arms and legs. By one year, most of the new HSCs were concentrated in the bones that make up the trunk of the body, including the hip, where most biopsies to assess marrow function take place.

Interestingly, notes Dr. Williams, this pathway is the same one that HSCs take in the fetus when they first form. Although experimental model research had previously suggested that transplanted HSCs travel the same route, little was known about whether HSCs in human patients followed suit.

The study also demonstrated that the radiation in ¹⁸F-FLT did not adversely affect engraftment. Additionally, images could identify success of their engraftments potentially weeks faster than they would have through traditional blood tests – a definite advantage to this technique.

“Through the images we took, these patients could see the new cells growing in their bodies,” Dr. Williams says. “They loved that.”

Besides providing an early heads up about engraftment status, she adds, this technique also could help patients avoid painful bone marrow biopsies to make sure donor cells have taken residence in the bones or at the very least help target those biopsies. It also could be helpful for taking stock of HSCs in other conditions, such as aplastic anemia, in which the body’s own HSCs fade away. And importantly, if the new healthy cells don’t grow, this test could signal this failure to doctors, enabling rapid mobilization of new cells to avert life-threatening infections and help us save lives after transplants at high risk of graft failure.

“What happens with HSCs always has been a mystery,” Dr. Williams says. “Now we can start to open that black box.”

Dr. Williams’ co-authors include co-lead author Jennifer Holter-Chakrabarty, M.D., Quyen Duong, M.S., Sara K. Vesely, Ph.D., Chuong T. Nguyen, Ph.D., Joseph P. Havlicek, Ph.D., George Selby, M.D., Shibo Li, M.D., and Teresa Scordino, M.D., University of Oklahoma; Liza Lindenberg, M.D., Karen Kurdziel, M.D., Frank I. Lin, M.D., Daniele N. Avila, N.P., Christopher G. Kanakry, M.D., Stephen Adler, Ph.D., Peter Choyke, M.D., and senior author Ronald E. Gress, M.D., National Cancer Institute; Juan Gea-Banacloche, M.D., Mayo Clinic Arizona; and Catherine “Cath” M. Bollard, M.D., MB.Ch.B., Children’s National.

Research reported in this story was supported by the National Institutes of Health, Ben’s Run/Ben’s Gift, Albert and Elizabeth Tucker Foundation, Mex Frates Leukemia Fund, Jones Family fund and Oklahoma Center for Adult Stem Cell Research.

Reducing harm, improving quality in the NICU

October 3, 2017

American health care is some of the most expensive in the world. To help make it more affordable, numerous efforts in all areas of medicine – from cancer care to primary care to specialized pediatrics – are focused on finding ways to improve quality and patient safety while also cutting costs.

About half a million babies born in the United States – or 10 percent to 15 percent of U.S. births – end up in the neonatal intensive care unit (NICU), most due to prematurity and very low birth weights. These vulnerable babies often need respiratory support in the form of a ventilator, which supplies oxygen to their lungs with a plastic endotracheal tube (ETT).

The typical care for these infants often involves frequent X-rays to verify the proper position of the tube. However, the American Academy of Pediatrics has counseled health care providers that ordering a daily chest X-ray simply to verify positioning of the ETT ratchets up costs without improving patient safety.

A quality-improvement initiative by Children’s National Health System’s NICU finds that these chest X-rays can be performed just twice weekly, lessening the chances of a breathing tube popping out accidentally, reducing infants’ exposure to radiation and saving an estimated $1.6 million per year.

“The new Children’s National protocol reduced the rate of chest X-rays per patient day without increasing the rate of unintended extubations,” says Michelande Ridoré, M.S., program lead in Children’s division of neonatology, who presented the research during the 2017 American Academy of Pediatrics (AAP) national conference. “That not only helps to improve patient safety – for newborns who are admitted to the NICU for longer periods, there is the additional benefit of providing significant savings to the health care system.”

Children’s NICU staff assessed how many chest X-rays were being performed per patient day before and after the protocol change, which applied to all intubated newborns in the NICU whose health condition was stable. Newborns had been undergoing a median of 0.45 chest X-rays per patient day. After the quality improvement project, that figure dropped to 0.23 chest X-rays per patient day.

When the project started in July 2015, the NICU’s monthly X-ray expenditure was $289,520. By the end of 2015, that monthly X-ray spend had fallen to $159,424 – resulting in nearly $1.6 million in annual savings.

The more restrictive strategy for ordering chest X-rays was a core component of a broader quality improvement effort aimed at lowering the number of unplanned extubations, which represent the fourth most common complication experienced by newborns in the nation’s NICUs.

“When you reduce the frequency of patients in the unit being moved, you decrease the chances of the breathing tube coming out accidentally,” Ridoré says. “By reducing unplanned extubations in the NICU, we can improve overall clinical outcomes, reduce length of stay, lower costs and improve patient satisfaction.”

When a breathing tube is accidentally dislodged, newborns can experience hypoxia (oxygen deficiency), abnormally high carbon dioxide levels in the blood, trauma to their airway, intraventricular hemorrhage (bleeding into the fluid-filled areas of the brain) and code events, among other adverse outcomes. What’s more, a patient with an unintended extubation can experience a nearly doubled hospital stay compared with the length of stay for newborns whose breathing tubes remain in their proper places. Each unplanned extubation can increase the cost of care by $36,000 per patient per admission.

To tackle this problem, Children’s National created the Stop Unintended Extubations “SUN” team. The team created a package of interventions for high-risk patients. Within one month, unintended extubations dropped from 1.18 events per 100 ventilator days to 0.59 events during the same time frame. And, within five months, that plummeted even further to 0.41 events per 100 ventilator days.

Their ultimate goal is to whittle that rate down even further to 0.3 events per 100 ventilator days, which has occurred sporadically. And the NICU notched up to 75 days between unintended extubations.

“Unintended extubation rates at Children’s National are lower than the median reported on various quality indices, but we know we can do more to enhance patient safety,” Ridoré says. ”Our SUN team will continue to address key drivers of this quality measure with the aim of consistently maintaining this rate at no more than 0.3 events per 100 ventilator days.”