Aug. 8 (UPI) -- Researchers at Baylor College of Medicine have developed a way to use virus-specific cells to protect patients against severe, drug-resistant viral infections.
The method is an alternative treatment to hematopoietic stem cell transplant using viral-specific cells to protect against infection.
Hematopoietic stem cell transplant is done to cure patients with certain cancers and other serious diseases who have not responded to chemotherapies. The transplant process on patients with compromised immune systems makes them vulnerable to infection for up to a year after the transplant and patients can develop life-threatening viral infections.
"In this study we continued our previous work in the Center for Cell and Gene Therapy, in which we showed that patients who had developed an Epstein-Barr virus infection after a transplant that led to a lymphoproliferative disease, could be helped by receiving immune cells specialized in eliminating that particular virus," Dr. Ifigeneia Tzannou, an instructor of medicine in the section of hematology and oncology at Baylor College of Medicine, said in a press release. "Then, we and others successfully targeted other viruses, namely adenoviruses and cytomegalovirus."
The study, published Aug. 7 in the Journal of Clinical Oncology, showed that the treatment is safe and effective against five different viruses.
"The novel contribution of this study is that we have targeted additional viruses, the BK virus and the HHV-6 virus, which had not been targeted this way before," said Dr. Bilal Omer, an assistant professor of pediatrics at Baylor and Texas Children's Hospital. "This is important because the BK virus does not have an effective treatment and the complications are significant, including severe pain and bleeding. These patients are in the hospital for weeks, months sometimes, and now we have a treatment option."
In order to prepare virus-specific cells researchers take blood from healthy donors who have already been exposed to the viruses and who have immune cells that can fight infections.
"We isolate the cells and let them multiply in culture," Tzannou said. "The final product is a mixture of cells that together can target all five viruses. We prepared 59 sets of virus-specific cells from different donors following this procedure."
The procedure was tested on 38 patients who had not responded to two other conventional anti-viral treatments and resulted in 92 percent overall complete or partial response rate.