Abstract:Objective:To study the effect of adenoviral vector expressing human IFNγ for transfecting human monocyte-derived DC (Ad-IFNγ-DC) on T cells prolifortion and differatition, and detect the anti-colonic cancer LoVo cells ability of actived T cells.
Methods :The recombinant adenovirus vector carrying IFNγ gene(Ad-IFNγ) was constructed using Adeno-XTM Expession System, then it was transfected into human monocyte-derivion DC(Ad-IFNγ-DC). After transfected, the IFNγ protein expression and cytokines secretion by DC were detected with LiquidChip method, the DC phenotypes were assayed with flow cytometry analysis, and the phagocytic ability of DC was assayed using FITC-Dextran uptake method. Subsequently, the capability of antigen pulsed Ad-IFNγ-DC to promote T cell proliferation and differentiation was detected using 3H-TdR incorporation and RT-PCR/ELISA method respectively. Finally, the ability of T cells to kill LoVo cells was detected with LDH release methods.
Results:Ad-IFNγ did not impact the phagocytic function of DC even after 24 h of transfection. DC transfected with Ad-IFNγ expressed IFNγ protein significantly stimulated T cells proliferation and enhanced T cells differatiated to TH1 cells, the which had especial kill ability of LoVo cells wa.
Conclusions:Ad-IFNγ transfection can promote DC maturation, enhance its capacities of antigen presentation and T cells stimulation, induce Th1 polarization and strong anti-LoVo cell immunities. These suggest that intratumoral administration of Ad-IFNγ-DC can eradicate tumors through a T cell-dependent mechanism.