Consideration of IL-2, IFN-γ and IL-4 expression and methylation levels in CD4+ T cells as a predictor of rejection in kidney transplant

Abstract

Kidney transplantation is the certain treatment for the end-stage-kidney disease patients. However after transplantation, allograft rejection or graft dysfunction are serious problems which the patients can be encountered. In several studies new biomarkers to predict rejection episodes tried to be evaluated and cytokines are thought to be one of these biomarkers. Additionally, epigenetic regulation of the cytokine genes can be an opportunity to detect the graft survival or dysfunction that lead to rejection. In this study, we aimed to detect the expression levels and methylation profile of cytokines IL-2, IL-4 and IFN-γ to follow the clinical situation of the patients. 25 kidney transplant patients were included in our study group and peripheral blood samples were collected before and 6 months after transplantation. CD4+ T cells were separated by using magnetic separation system and expression levels are detected by qPCR while methylation profile analysis was performed by pyrosequencing. According to our study we noticed that all of the patients with allograft rejection have increased expression levels of IFN-γ. When methylation profile of the CpGs in the promotor region of IFN-γ is evaluated, +128CpG was found as methylated when compared with +122. In conclusion, epigenetic mechanisms can effect several processed in renal transplantation and further studies with higher numbers of patients are needed to detect new biomarkers for prediction of allograft rejection.

Keywords: Allograft rejection; CD4+ T cells; Kidney transplantation; Methylation.