Factors affecting the presentation of exogenous Hepatitis-B virus core antigen

Hepatitis-B virus core antigen (HBcAg) plays a critical role in terminating acute Hepatitis-B virus infection and may be used as a potential vaccine candidate. The cell surface MHC class-I molecules are thought to be involved in the presentation of HBcAg. The article characterizes MHC class-I HLA A2 heavy chain (HC) and trimeric molecules on the surface of transfected HeLa cells which were used for the presentation of HBcAg. The work presented shows that antibodies against the HC HLA A2 and trimeric HLA-A2 molecules resulted in increased activation of HBcAg 18–27 minimal peptide specific CTLs, while the addition of exogenous β2-microglobulin decreased activation of HBcAg specific CTLs. Further the article demonstrates that CD₈⁺ T-cells were activated only when HeLa cells as APCs were pulsed at low pH with HBcAg 1–124 (soluble), HBcAg1-144 and HBcAg1-183 opsonized on virosomes.