Effect of T-lymphocyte phenotype on immune status in chronic hepatitis B virus infection and its application value

Objective To investigate the association between T-lymphocyte phenotype and immune status in chronic hepatitis B(CHB)and its application value.Methods A total of 77 CHB patients who attended The First Hospital of Lanzhou University from January 2015 to May 2019 were enrolled, and according to the status of HBeAg and the serum levels of alanine aminotransferase(ALT), HBsAg, and HBV DNA, they were divided into immune tolerance group and non-immune tolerance group. The laboratory results of T-lymphocyte phenotype, HBV serological test, HBV DNA load, routine blood test, and liver function were obtained, and aspartate aminotransferase-to-platelet ratio index(APRI) and fibrosis-4(FIB-4) were calculated. Thettest was used for comparison of normally distributed continuous data between two groups; and the Mann-WhitneyUtest was used for comparison of non-normally distributed continuous data between two groups; the chi-square test was used for comparison of categorical data between groups. Spearman correlation analysis was used to test the correlation effect between the two variables. The diagnostic efficacy of Treg, CD8+PD-1+T lymphocyte percentage and CD8+CD45 RO+T lymphocyte percentage were evaluated by AUC.Results Compared with the non-immune tolerance group, the immune tolerance group had significantly higher percentages of Treg and CD8+PD-1+T cells(U= 12. 0 and 59. 0,P< 0. 001,P= 0 013) and significantly lower percentages of CD3+CD8+T cells and CD8+CD45 RO+T cells(U= 50. 0 and 38. 5, bothP< 0. 05). Compared with the high HBV DNA load group, the low HBV DNA load group had significantly lower percentages of Treg and CD8+PD-1+T cells(U= 178 5 and 255.0,P= 0. 003 and 0. 018) and significantly higher percentages of CD3+T cells and CD8+CD45 RO+T cells(U= 104. 0 and1495,P= 0. 033 and 0. 025). APRI was negatively correlated with the percentage of Treg(r=-0. 379,P= 0. 013), and FIB-4 was negatively correlated with the percentages of CD3+CD4+, CD3+CD8+, CD4+CD45 RO+, and CD8+CD45 RO+T cells(r=-0. 259,-0. 275,-0. 233, and-0. 229,P= 0. 023, 0. 016, 0. 041, and 0. 045). Treg, CD8+PD-1+T cells, and CD8+CD45 RO+T cellshad an area under the ROC curve of 0. 793(95% confidence interval [CI]: 0. 651-0. 936), 0. 802(95% CI: 0. 678-0. 927), and0. 816(95% CI: 0. 706-0. 927), respectively, in evaluating immune status.Conclusion There are various T-lymphocyte phenotypesin patients with chronic HBV infection, and different T lymphocytes have different abilities to eliminate HBV. Detection of T-lymphocytephenotype helps to understand the immune status and adjust the immune function in CHB patients and can provide a reference for the func-tional cure of CHB patients.