Effect of recombinant adenovirus Ad-PD-L1 transfection of donor mouse dendritic cells on the activation of receptor mouse lymphocytes

Abstract

AIM: To investigate the effect of recombinant adenovirus Ad-PD-L1 transfection of donor mouse C57BL/6 (H-2(superscript b)) dendritic cells on the activation of receptor mouse DBA/2(H-2(superscript d)) lymphocytes. METHODS: pShuttle-GFP-CMV(-) plasmid and adenovirus bone plasmid pAdxsi-GFP-CMV- PD-L1 were constructed. The recombinant adenovirus Ad-PD-L1 was packed, amplied and purified. Dendritic cells derived from donor mouse C57BL/6 bone marrow were isolated and cultured. The cells ware divided into 3 groups. Group A and Group B were transfected with recombinant adenovirus Ad-PD-L1-GFP and Ad-GFP respectively, and Group C served as blank control group. The expression of PD-L1 was monitored by GFP fluorescence in the infected ceL1s and identified by Western blot. The lymphocytes of receptor mouse DBA/2 were isolated, and then labeled by carboxyfluorescein succinimidylester (CFSE). After co-cultured with the dendritic ceL1s in the three groups, flow cytometry was used to observe the proliferation and activation of lymphocytes from DBA/2 mice. RESULTS: Enzyme digestion and sequencing confirmed the successful construction of recombinant adenovirus Ad-PD-L1. After transfection with Ad-PD-L1, PD-L1 expression of dendritic cells was verified by Western blot. The expression of PD-L1 in the dendritic ceL1s infected with Ad-PD-L1 was increased by 37% (P＜0.05). After co-cultured with the lymphocytes from DBA/2 mice, the proliferation and activation of receptor lymphocytes were suppressed remarkably, and the proliferation rate was decreased by 41% as compared with that in the control group. CONCLUSION: Transfection of donor mouse dendritic cells with recombinant adenovirus suppresses the proliferation and activation of lymphocytes from receptor mice through PD-l/PD-L1 co-stimulatory pathway.