Interleukin-17 gene expression and serum levels in acute rejected and non-rejected liver transplant patients.

BACKGROUND Interleukin-17 (IL-17), as a potent proinflammatory cytokine, has a critical role in post liver transplant outcomes. However, there is not much information about the effects of IL-17 cytokine on acute liver rejection. OBJECTIVE To evaluate the role of IL-17 in post-liver transplant acute rejection. METHODS Ninety seven adult liver transplant patients who enrolled in this cross sectional study were divided into Non-Acute Rejected (Non-AR) and Acute Rejected (AR) patient groups. Three blood samples were collected from each patient in days 1, 4 and 7 post liver transplantation. The IL-17 mRNA levels were evaluated using an in-house real time PCR protocol. IL-17 protein levels were also analyzed in Non-AR, AR and also control groups using ELISA method. RESULTS The IL-17 mRNA expression level continuously increased in AR patients in all days of follow-up post liver transplantation. IL-17 expression was, however, down regulated after day 4 post-transplant follow-up in Non-AR patients. Both IL-17 mRNA expression and protein levels were also significantly increased in AR patients compared with Non-AR ones. CONCLUSION Based on these findings, significant increase of IL-17 mRNA and protein levels in AR patients highlights the important role of IL-17 in acute liver rejection.