Effects of PTD-HBcAg induced murine bone marrow-derived dendritic cells maturation on T lymphocyte proliferation in vitro / 中华传染病杂志

ABSTRACT

Objective To observe the effects of PTD-hepatitis B core antigen (HBcAg) induced murine bone marrow-derived dendritic cells (DCs) maturation on T lymphocyte proliferation in vitro.Methods Bone marrow derived DCs isolated from BALB/c mice were cultured with recombinant granu|ocyte-macrophage colony-stimulating factor (rGM-CSF) and recombinant interleutin-4 (rIL-4)for 5 days.Tumor necrosis factor (TNF)-a,HBcAg and PTD-HBcAg were added to induce DCs maturation.The distribution and localization of intracellular immunofluorescence were observed by confocal microscopy,and DCs phenotypes were analyzed by flow cytometry.The level of IL-12 p70 in the supernatant was detected by enzyme linked immunosorhent assay (ELISA).The proliferation of T lymphocytes was performed by using cell counting kit-8 (CCK-8).All data were analyzed using t test.Results DCs were cultured and identified successfully.Recombinant PTD-HBcAg could penetrate into DCs cytoplasm while recombinant HBcAg was detected on the surface of cells.DCs surface molecules,such as CD80,CD86 and major histocompability complex (MHC) II were upregulated by PTDHBcAg;IL-12 p70 levels induced by 50 mg/L and 100 mg/L recombinant PTD-HBcAg were (142.50±18.31) ng/L and (124.30±15.12) ng/L,respectively,which were significantly higher than those induced by recombinant HBcAg [(42.31±4.21 ) ng/L,t = 9.234 and 9.045,respectively,P＜0.05].The proliferation of T lymphocytes induced by PTD-HBcAg was much higher than that in HBcAg group or positive control TNF-a group.Conclusions PTD-HBcAg could penetrate membrane of DCs and promote the differentiation and maturation of DCs.PTD-HBcAg could up-regulate the expressions of costimulatory molecules on cell surface of DCs,and enhance the ability of DCs on stimulating T lymphocytes proliferation and IL-12 p70 production.