Association between IL7RA polymorphisms and the successful therapy against HCV in HIV/HCV-coinfected patients

Interleukin-7 (IL-7) is a critical factor in maintaining or inducing effective antiviral CD4+ and CD8+ T-cell responses. The aim of this study was to examine the association of interleukin-7 receptor-alpha (IL7RA) polymorphisms with a sustained virologic response (SVR) after hepatitis C virus (HCV) therapy with pegylated interferon-alpha plus ribavirin (pegIFN alpha/ribavirin) in 177 human immunodeficiency virus (HIV)/HCV-coinfected patients. We performed a retrospective study in 177 na < ve patients who started HCV treatment. The IL7RA rs6897932, rs987106, and rs3194051 polymorphisms were genotyped by the GoldenGateA (R) assay. An SVR was defined as undetectable HCV viral load through 24 weeks after the end of HCV treatment. The highest SVR rate was found in patients with the rs6897932 CC (p = 0.029) and rs3194051 GG (p = 0.002) genotypes, and HCV genotypes 2/3 (GT2/3) infected patients with the rs987106 AA genotype (p = 0.048). Additionally, carriers of the rs3194051 GG genotype had a higher likelihood of achieving an SVR [adjusted odds ratio (aOR) = 5.32; 95 % confidence interval (CI) = 1.07-26.94; p = 0.040] than patients with the rs3194051 AA/AG genotype, while rs6897932 CC (aOR = 0.63; p = 0.205) and rs987106 AA (aOR = 0.60; p = 0.213) were not significant. Moreover, three major haplotypes were found: 46.6 % for CTA, 32.4 % for CAG, and 20.7 % for TAA haplotypes. Patients infected with GT2/3 and carriers of the CTA haplotype had lower odds of achieving an SVR (aOR = 0.08; p = 0.004) and the CAG haplotype (favorable alleles) had higher odds of achieving an SVR than other haplotypes (aOR = 21.96; p < 0.001). IL7RA polymorphisms seem to play a significant role in the virological response to pegIFN alpha/ribavirin therapy in HIV/HCV-coinfected patients, in particular among patients infected with HCV GT2/3.