Scientists at the University of Pittsburgh have developed tiny particles that can trick the body into accepting transplanted tissue as its own. The particles were inspired by a tactic cancer cells use to evade the immune system.
"It's like hacking into the immune system borrowing a strategy used by one of humanity's worst enemies to trick the body into accepting a transplant," said senior author Steven Little, Ph.D., William Kepler Whiteford Endowed Professor and Chair of chemical and petroleum engineering in the Swanson School of Engineering at Pitt. "And we do it synthetically."
Simpler treatment logistics
This synthetic approach offers much simpler treatment logistics.
"Instead of isolating cells from a patient, growing them up in the lab, injecting them back in and hoping they find the right location, we're packaging it all up in an engineered system that recruits these naturally occurring cells right to the transplanted graft," said lead author James Fisher, M.D., Ph.D., a postdoctoral researcher in the Pitt School of Medicine.
The researchers found that microparticle-treated rats maintained healthy grafts for a little under a year. This translates to 30 human years. This was the period in which the rats were monitored which means the grafts could likely be maintained even longer.
Replacing immunosuppressant drugs
If so, the new treatment could soon replace the need for transplant patients to take immunosuppressant drugs.
"These drugs hammer the immune system into submission so it can't attack the transplanted organ, but then it can't protect the body either," said coauthor Stephen Balmert, Ph.D., a postdoctoral researcher in the Pitt School of Medicine. "We're trying to teach the immune system to tolerate the limb, so that a transplant recipient can remain immunocompetent."
Studies also found that the microparticles could train the immune system of one strain of rat to accept a donor limb from a different strain. If the microparticles prove indeed successful as a viable alternative to immunosuppressant drugs, they would provide a much healthier and safer way to accept transplants.
The study is published in Science Advances.