The study of heat shock protein 70 as a adjuvant carrier on HBV-specific immune response in vitro / 重庆医学

ABSTRACT

Objective To investigate the effect of mycobacterium tuberculosis heat shock protein 70(TB .HSP70) as an adjuvant carrier on stimulating hepatitis B virus (HBV) core antigen(HBcAg)specific immune response to an accompanying cytotoxic T lym-phocytes epitope peptide from HBV core antigen in vitro .Methods Recombinant proteins HSP70(P1)、HSP70-HBcAg(18-27) (P2)、HSP70-PreS2B (18-24)-PreS2Th(37-53)-HBcAg(18-27)(P3) were expressed in methylotropic yeast Pichia pastoris GS115 . The expression of recombinant proteins was identified by SDS-PAGE and Western blot .The effect of recombinant proteins on den-dritic cell and lymphocytes of chronic HBV infection volunteers was investigated in vitro .The maturation of dendritic cell was meas-ured by flow cytometry ;the secretion of Th1 cytokines such as IL-12p70 ,IL-1β,TNF-αand IFN-γ was measured by ELISA ;the proliferation of lymphocytes was measured by TdR-3H ;the HBV-spesific cytotoxic activity was measured by the classic 51 Cr .Re-sults The recombinant proteins (P1 ,P2 ,P3) were constructed successfully .P1 ,P2 ,P3 could activate dendritic cell from chronic HBV infection volunteers by upregulation CD1a ,CD40 ,CD86 and production Th1 cytokines such as IL-12p70 ,IL-1β and TNF-α. Especially P3 could better induce autologous T cells to generate HBV specific cytotoxic T lymphocytes response ,activate the prolif-eration of lymphocytes and release IFN-γeffectively .However ,the recombinant HSP70 showed no target cell killing and could not induce immune response effectively .Conclusion TB .HSP70 can be used as an adjuvant carrier to stimulate HBV specific immune response to an accompanying cytotoxic T lymphocytes epitope peptide from HBV core antigen ,and enhance immunogenicity of the cytotoxic T lymphocytes epitope peptide .The P3 with B-and T-epitope can activate the HBV specific immune response effectively .