Gastric cancer-derived heat shock protein-gp96 peptide complex enhances dendritic cell activation

AIM To investigate the role of heat shock protein(HSP)-glycoprotein(gp)96 in dendritic cells(DCs)and lymphocytes induction in gastric cancer(GC). METHODS Human GC cell lines KATOIII,MKN-28 and SGC-7901were infected with adenovirus gp96 at a multiplicity of infection of 100.gp96-GC antigen peptide complexes were purified.MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)assay,lactate dehydrogenase(LDH)release assay and enzymelinked immunosorbent assay were used to determine allo-reactive T cell stimulation,natural killer(NK)cell activity and expression of cytokines(such as interleukin(IL)-10,IL-12,interferon(IFN)-γand tumor necrosis factor(TNF)-α),respectively.Effect of cytotoxic T lymphocyte(CTL)on DCs incubated with HSP-gp96was also evaluated by LDH release.All assays were performed in triplicate and the average values were reported.Comparison between groups was conducted using Student’s t test.RESULTS T cells incubated with HSP-gp96 exhibited a marked increase in proliferation in a dose-dependent manner(P<0.05).NK cell activity after gp96-GC peptide complex treatment was significantly higher than that after antigen peptide treatment(P<0.05).The activity of CTLs incubated with DCs from three GC cells lines was obviously higher than that stimulated by GC antigen at ratios of 50:1,25:1,10:1,and 5:1(P<0.05).Furthermore,the secretion of TNF-α,IL-10,IL-12(P70)and IFN-γmarkedly increased after incubation with HSP-gp96(P<0.05).CONCLUSION HSP-gp96 promotes T cell response,enhances DC antigen presentation and induces cytokine secretion,as well.HSP-gp96 has potential as immunotherapy for elimination of residual GC cells.