If a corneal transplant patient's body rejects a donor graft once, his prospects for success in a second attempt aren't high. But researchers at the University of Texas Southwestern Medical Center in Dallas are exploring a technique that could boost transplant acceptance rates even after initial failures.
Previous research has established that an immune system molecule called interferon-gamma (IFN-y) triggers the body's rejection response. It has further speculated that deactivating IFN-y could remove this hurdle. But the UT Southwestern researchers, writing in the December issue of the American Journal of Transplantation, report that acceptance depends on more than just this step.
Conducting a mouse study, they found that when IFN-y was deactivated and mice shared major histocompatibility complex (MHC) genotypes with donors, the result was a 90% transplant acceptance rate. If, however, IFN-y was deactivated and MHC was not a match, the result was 100% rejection.
This finding, they say, could improve the chances of acceptance among the approximately 10% of patients whose bodies have rejected previous corneal transplant attempts or who are at high risk of rejection. The researchers are working to develop and test IFN-y antibody eye drops for pre-surgical therapy.