Anyone who has had the misfortune of being an organ transplant recipient knows how complicated it is. While simply swapping organs for newer and healthier ones seems pretty straightforward, it is anything but.
If you did not know already, many of our organs can be replaced. In fact, certain heart and liver diseases are often so severe that organ transplant is the only option. Several cancers also rely on the donation of bone marrow transplants for a cure.
While organ transplants are a great form of therapy, over time, the body begins to slowly reject the organ by mounting immune responses.
It is estimated that about seven percent of transplants will fail within the first year, with that number climbing to 17 percent within three years. At about 10 years, it is estimated that only 54 percent of transplanted kidneys will still be working.
The methods for prolonging this inevitable organ rejection include lifelong treatment with immune inhibiting medication. While this does decrease rejection risk, it limits the ability of the patient to fight off infections that they may contract.
A collaboration between researchers from the University of Pittsburgh School of Medicine and the University of Toronto have uncovered the first molecular steps that lead to the activation and eventual rejection of a transplanted organ.
This discovery may someday lead to better donor-recipient organ matches and even help develop new and better ways to prevent rejection from occurring over the long term.
“For the first time, we have an insight into the earliest steps that start the rejection response. Interrupting this first recognition of foreign tissues by the innate immune system would disrupt the rejection process at its earliest inception stage and could prevent the transplant from failing,” said the study’s co-senior author Fadi Lakkis, M.D.
The researchers used genetic mapping in mice for their research, discovering a molecule called SIRP-alpha that leads to an organ rejection immune system activation. Humans also express this molecule, making this discovery all the more relevant.
They found that blocking this molecule successfully prevented recipient immune system activation.
While more research is still needed, future studies will surely use these findings as a basis for creating a new way to prevent organ rejection.