Development of monitoring assays to accurately assess the immune status of transplant recipients is of crucial importance in the field of transplant immunobiology. Such assays may enable transplant physicians to use the highly toxic and expensive immunosuppressive drugs in a more rational way rather than on empiric basis, thus avoiding enormous cost and side effects. Moreover, such assays may give us clinically useful information regarding graft outcome leading to preemptive treatment in high risk individuals, and evaluating the response to such a treatment. As the ultimate goal in transplantation is drug-free allograft acceptance, there is urgent need for development of rapid and reliable assays to establish “surrogate markers” for rejection and tolerance. Ideal assays have high positive and negative predictive value, diagnose rejection (acute and/or chronic) before its occurrence, and should be rapid, non-invasive and inexpensive.
This lecture will review the state of the art on surrogate markers of allograft rejection and tolerance, put in a clinical perspective.