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Michael Keller

Virus-specific t-cells show promise before transplant in SCID patients

Michael Keller

“Today, we know that virus-specific T-cells can help protect patients from dangerous viruses after stem cell transplants,” says Michael Keller, M.D. “Through this research, we used the same therapy and approach, but applied it pre-transplant with the hope of providing the same benefit of protection against life-threatening viruses to patients who need it the most.”

Experts at Children’s National Health System have been successfully studying the use of virus-specific T-cells (VST) to help protect immunocompromised patients from life-threatening viruses after bone marrow transplants. Research published recently in the Biology of Blood and Marrow Transplantation presents promising new findings from testing the use of these same VSTs before transplant to help give patients with severe combined immunodeficiency (SCID) a better chance at long-term survival.

Babies born with SCID are highly susceptible to severe infections that are often fatal if not treated with immune-restoring treatments, like hematopoietic stem cell transplants (HSCT). However, undergoing an HSCT with an infection present has shown to lead to a decrease in survival at two years old for SCID patients when compared to those who start the HSCT infection-free. The study lead, Michael Keller, M.D., hypothesized that the success of HSCTs in SCID patients may be improved by controlling severe viral infections before the patient undergoes the transplant.

“Today, we know that virus-specific T-cells can help protect patients from dangerous viruses after stem cell transplants,” says Dr. Keller. “Through this research, we used the same therapy and approach, but applied it pre-transplant with the hope of providing the same benefit of protection against life-threatening viruses to patients who need it the most.”

Dr. Keller administered the VSTs from a healthy third-party donor in a five-month-old infant fighting adenovirus before undergoing a HSCT to cure him of SCID. Today, the baby is healthy and has a normal immune system. Ultimately, this research shows that the use of VSTs is likely safe in the pre-HSCT period in patients with SCID and may be an effective therapy for viral infections when they are resistant to antiviral therapy.

“I believe this VST therapy could make a real and lasting impact for patients with SCID,” said Dr. Keller. “It gives them a real chance at a long life.”

Anthony Sandler

Treatment of neuroblastoma with immunotherapy and vaccine combination shows promise

Anthony Sandler

“Treatment options like these that help the body use its own immune system to fight off cancer are incredibly promising, and we look forward to continuing this work to understand how we can best help our patients and their families,” said Anthony Sandler, M.D.

Despite being the most common extracranial solid tumor found in children and having multiple modes of therapy, neuroblastoma continues to carry a poor prognosis. However, a recent cutting-edge pre-clinical study, PD-L1 checkpoint inhibition and anti-CTLA-4 whole tumor cell vaccination counter adaptive immune resistance: A mouse neuroblastoma model that mimics human disease, published in PLOS Medicine shows the first signs of success in treating high-risk neuroblastoma, a promising step not only for neuroblastoma patients, but potentially for other types of cancer and solid tumors as well. While the research was conducted on mouse models and is in the early stages, the lead author of the study, Anthony Sandler, M.D., senior vice president and surgeon-in-chief of the Joseph E. Robert, Jr., Center for Surgical Care at Children’s National, believes these findings are an encouraging development for the field.

The treatment method combines a novel personalized vaccine and a combination of drugs that target checkpoint inhibitors enabling the immune system to identify and kill cancer cells. When these checkpoints are blocked, it’s similar to taking the brakes off the immune system so that the body’s T cells can be primed by the vaccine, identify the tumor and allow for targeted tumor cell killing. The vaccine then brings in reinforcements to double down on the attack, helping to eradicate the tumor. The vaccine could also be used as a way to prevent recurrence of disease. After a patient has received the vaccine, the T cells would live in the body, remembering the tumor cells, and attack reemerging cancer in a similar way that a flu vaccine helps fight off the flu virus.

“Treatment options like these that help the body use its own immune system to fight off cancer are incredibly promising, and we look forward to continuing this work to understand how we can best help our patients and their families,” said Dr. Sandler.