Diagnostic value of T-cell monitoring assays in kidney transplantation

Abstract

Personalized immunosuppressive therapy on the basis of the recognition of individual alloreactive and anti-infectious immune responses is a major goal in clinical transplantation. It requires the development of reliable assays for quantification of T-cell responses. Here, we review recent findings in the field of T-cell immune monitoring focusing on candidate assays with clinical utility for predicting outcome in kidney transplantation. Promising assays for routine monitoring of T-cell reactivity in transplant patients include IFNgamma Elispot, multiparameter flow cytometry and intracellular ATP assay. Although large randomized multicenter studies are still lacking, first clinical applications have demonstrated remarkable differences in alloreactive and anti-infectious T-cell reactivity of transplant patients with potential for predicting outcome. Currently, standardization of the tests is a major challenge for translation into multicenter trials. A definitive picture of the (allo)immune response would require the assessment of multiple biological and genetic markers. However, frequent and reliable T-cell monitoring is feasible by simple cellular assays such as IFNgamma Elispot and intracellular ATP determination. International efforts are warranted for further standardization of these assays. Furthermore, the implementation of T-cell monitoring assays in large randomized clinical studies assessing different immunosuppressive regimens and weaning procedures is clearly required.