[Association of circulating levels of soluble PD-1, PD-1 gene polymorphisms with HBV infection and HBV infection-associated hepatocellular carcinoma].

Objective: To investigate the association of circulating sPD-1 level and PD-1 gene polymorphisms with HBV infection and HBV infection-associated hepatocellular carcinoma. Methods: A case-control study was conducted. A total of 237 chronic HBV infection cases and 138 HBV infection-associated hepatocellular carcinoma in the Department of Infectious Diseases of the First Hospital of Shanxi Medical University from 2018 to 2021 were selected as the case group. About 250 individuals who visited a hospital physical examination center for routine physical examination during the same period were selected as the control group. Plasma sPD-1 levels were measured by using an ELISA kit and genotyping was performed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The association of sPD-1 levels and PD-1 polymorphisms with HBV infection as well as HBV infection-associated hepatocellular carcinoma was analyzed by using logistic regression models after adjusting for age, sex, alcohol consumption, smoking, ALT and AST levels. The sPD-1 level and PD-1 polymorphisms were independent variables, and HBV infection was the dependent variable. Results: The age of 237 chronic HBV infections, 138 HBV infection-related liver cancer case subjects and 250 control subjects in the study was (49.1±10.8), (51.9±12.7) and (50.7±11.9) years, respectively. Multivariate logistic regression model analysis showed that with a 1 pg/ml increase in sPD-1 level, the OR (95%CI) values for the risk of incident HBV infection cases and HBV hepatocellular carcinoma cases were 1.92 (1.68-2.19) and 2.02 (1.69-2.40). For rs2227981, compared with the CC genotype, the TT genotype had a lower risk of HBV infection and liver cancer associated with HBV infection, with OR (95%CI) values of 0.45 (0.22-0.91) and 0.35 (0.14-0.91). For rs2227982, compared with the CC genotype, the CT and TT genotypes also had a lower risk of HBV infection [OR (95%CI) values of 0.72 (0.53-0.97) and 0.57 (0.35-0.93)] and HBV infection-related liver cancer [OR (95%CI) values of 0.64 (0.45-0.92) and 0.52 (0.29-0.93)]. Conclusions: Plasma sPD-1 levels and PD-1 gene polymorphisms are associated with HBV infection and HBV infection-associated hepatocellular carcinoma.