Fran Lund, Ph.D., and John T. Killian, M.D., Ph.D. When a patient undergoes an organ transplant, failure to match the donor and recipient can lead to the recipient’s immune system’s attacking the new organ, a process triggered by a specific human leukocyte antigen, or HLA, protein. In a recent study published in Immunity, researchers from the University of Alabama at Birmingham Marnix E.