Determination of proportions of T cell subsets and levels of interleukin-15 and interleukin-16 in peripheral blood of patients with chronic hepatitis B virus infection and correlation between them

Objective To investigate the variation and clinical significance of T cell subsets( CD3+,CD4+,CD8+,and CD4+/ CD8+)and levels of cytokines,interleukin( IL)-15 and IL-16,in peripheral blood of patients with chronic hepatitis B virus( HBV) infection.Methods A total of 63 patients with chronic hepatitis B( CHB),112 asymptomatic carriers( ASC) of HBV,and 84 healthy controls who were treated in our hospital from July to December,2014,were assigned to CHB group,ASC group,and control group,respectively. In the three groups,the serum T cell subset populations were determined using flow cytometry; the expression of cytokines,IL-15 and IL-16,was measured by enzyme-linked immunosorbent assay; the HBV DNA load was measured by polymerase chain reaction. Comparison of data between multiple groups was made by analysis of variance. The data in each group were subjected to Pearson correlation analysis. Results Compared with the control group,the CHB and ASC groups had significantly lower CD3+,CD4+,and CD4+/ CD8+T cell proportions but a significantly higher CD8+T cell proportion( all P < 0. 05). The CHB and ASC groups also had significantly higher expression of IL-15 and IL-16 than the control group( all P < 0. 05). In the CHB group,patients with a high HBV DNA load had significantly lower CD3+,CD4+,and CD4+/ CD8+T cell proportions but a significantly higher CD8+T cell proportion than those with a low HBV DNA load( all P <0. 05). In the ASC group,patients with a high HBV DNA load had significantly lower CD4+and CD4+/ CD8+T cell proportions but a significantly higher CD8+T cell proportion than those with a low HBV DNA load( all P < 0. 05). In the peripheral blood of patients in the CHB group,the expression of CD4+was positively correlated with the expression of IL-15( r = 0. 516,P < 0. 05),while the expression of CD8+was positively correlated with the expression of IL-16( r = 0. 665,P < 0. 05). In the peripheral blood of patients in the ASC group,the expression of CD3+was positively correlated with the expression of IL-15( r = 0. 618,P < 0. 05). Conclusion Patients with HBV infection have abnormal proportions of T cell subsets. Cytokines,IL-15 and IL-16,may induce different degrees of cellular immune dysfunction and dysregulation.