Study on HBV antigens and IL-12 affecting T cell-mediated immunity in HBsAg carriers / 中华肝脏病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of HBV antigens and pathological mechanism of chronic HBV infection by analyzing the cellular immune function of peripheral blood mononuclear cells (PBMCs) from HBsAg carriers.</p><p><b>METHODS</b>PBMCs were prepared from individuals with chronic asymptomatic HBV infection and cultured in the presence of different antigens and/ or cytokines. The levels of cytokines in culture supernatants were detected by ELISA method. The phenotype of the cells was detected by FACS.</p><p><b>RESULTS</b>The levels of IFN y secreted by PBMCs from HBsAg carriers were (48.3+/-19.8) pg/ml, significantly lower than that from healthy controls (t = 3.023, P less than 0.05); The IFN y produced by PBMCs from HBeAg positive patients due to HBsAg and HBcAg stimulation were (50.4+/-51.6) pg/ml and (63.2+/-36.9) pg/ml, significantly lower than that of HBeAg negative patients (t = 2.468 and 3.184, P less than 0.05, respectively). The IL-12p70 secreted by PBMCs from HBeAg positive patients was also significantly lower than that of HBeAg negative patients (P less than 0.05); Exogenous IL-12 promoted significantly PBMCs to secrete IFN y (P less than 0.01) and IL-12 combined with HBV antigens activated CD8+CD45RA+CCR7+ and CD8+CD45RA-CD62L+ cells. IL-12 secreted by PBMCs decreased in HBeAg positive patients, which may be the crucial reason of viral persistence in chronic HBV carriers. Exogenous IL-12 combined with specific HBV antigen could promote the central memory CD8+ T cells to produce IFN y.</p>