Sequential monitoring of peripheral T-lymphocyte cytokine gene expression in the early post renal allograft period

Background. Despite numerous studies, the precise role of cytokines in acut e renal allograft rejection remains unclear. In this study we have monitore d sequential changes in peripheral T cell cytokine gene expression, correla ting the changes with clinical events after adult renal transplantation, to provide a deeper insight of the role of cytokines in allograft rejection. Methods. Sequential changes in peripheral Th-1 [interleukin- (IL) 2 and int erferon-gamma] and Th-2 (IL-4, IL-5, IL-10, and IL-13) cytokine gene expres sion in 43 patients with (n=15) and without (n=28) episodes of biopsy-prove n rejection was monitored in the first 6 weeks after renal transplantation using a sensitive, semi-quantitative reverse-transcriptase polymerase chain reaction ELISA approach. Results. Th-2 cytokines: IL-5 and IL-13 expression increased before and dur ing acute rejection, and decreased after successful antirejection therapy. A significant fall in IL-4 expression after transplantation and subsequent return to its baseline level of expression was observed in both nonrejector s and rejectors. IL-10 showed persistently high expression in nonrejectors, but in rejectors the expression fell during acute rejection, with a subseq uent rise after antirejection therapy. Th-1 cytokines: IL-2 and IFN-gamma d ecreased in expression in the first week posttransplant in the rejectors, a t the time of acute rejection (IL-2 only) and immediately after completion of antirejection therapy. Conclusions. Sequential monitoring of peripheral T cell cytokine gene expre ssion after renal transplantation detected changes in expression that corre lated with episodes of acute rejection and response to antirejection therap y. This approach may be applicable in the clinical laboratory for monitorin g posttransplant changes in T cell alloreactivity and immunosuppression.