Association of IL-17, IL-21, and IL-23R Gene Polymorphisms with HBV Infection in Kidney Transplant Patients

Inflammatory cytokine gene polymorphisms may influence the hepatic and extrahepatic HBV-related disease in transplant patients. In this study, the association between IL-17, IL-23R, and IL-21 gene polymorphisms with hepatitis B virus (HBV) infection was evaluated in kidney transplant patients. In total, 220 kidney transplant patients were enrolled in this cross-sectional study between years 2007 and 2011. The genomic HBV DNA was identified using an HBV PCR detection Kit according to the manufacturer's instruction. The cytokine gene polymorphisms, including IL-17 197A/G (rs2275913), IL-21 + 1472 G/T (rs2055979), IL-21 5250 C/T (rs4833837), and IL-23R C/A (rs10889677) were evaluated by PCR-RFLP and ARMS-PCR protocols. The serum levels of IL-17 and IL-21 were analyzed in HBV infected and noninfected transplant patients by ELISA methods according to manufacturer's instructions. 70 of 220 (35%) transplant patients experienced acute rejection. HBV DNA was detected in 52 of 220 (23.64%) transplant patients. 16 of 52 (30.8%) HBV-infected kidney transplant patients experienced acute rejection. A significant higher frequency of C allele of IL-23R (rs10889677) polymorphism, a higher frequency of AG heterozygote genotype and A allele of IL-17-G197A (rs2275913) polymorphism, a higher frequency of TT homozygote genotype and T allele of IL-21-G1472T (rs2055979) polymorphism, and a higher frequency of CC homozygote genotype and C allele of IL-21-C5250T (rs4833837) polymorphism were found in HBV-infected kidney transplant patients with acute rejection. Diagnosis of the higher frequency of the IL-17, IL-21, and IL-23R cytokine genotypes and allele polymorphisms in HBV-infected kidney transplant patients who experienced acute rejection, illustrates the importance of Th17-related cytokine genetic patterns. A better evaluation of HBV infection in kidney transplant patients is needed.