PDL1, ligand of immune checkpoint PD1, regulated the immune response and effect on chronic viral infection. Genetic differences including polymorphisms and mutations can play a vital role in Human T-cell leukemia virus type 1(HTLV-1) infection and proviral load (PVL). PVL is significantly higher in symptomatic patients compared to asymptomatic carriers (ACs); thus PVL would be a prognostic marker of HTLV-1 disease progression.
So in this case–control study that contained 81 ACs and 162 healthy controls (HCs), the rs4143815 polymorphism of PDL1 gene, a site for binding to miR-570, was evaluated with allele-specific polymerase chain reaction (AS-PCR) and PVL level measured by quantitative real-time PCR (q PCR). Association of rs4143815 polymorphism with HTLV-1 and PVL were analyzed by SPSS-22 statistical software based on chi-square test and T-test.
The results showed that ACs had higher frequency of CC genotype (p=0.031) and C allele (p=0.027) compere to HCs also, PVL was significantly higher among ACs with C allele (p=0.020).
Our results suggest that the rs4143815 polymorphism can play important role in HTLV-1 infection and PVL.
Gene polymorphism; Human T-lymphotropic virus 1; PD-L1; Viral load