Adenovirus vaccine therapy with CD137L promotes CD8+ DCs-mediated multifunctional CD8+ T cell immunity and elicits potent anti-tumor activity. (January 2022) - Ding, Jiage
Abstract: Renal carcinoma progresses aggressively in patients with metastatic disease while curative strategies are limited. Here, we constructed a recombinant non-replicating adenovirus (Ad) vaccine encoding an immune activator, CD137L, and a tumor antigen, CAIX, for treating renal carcinoma. In a subcutaneous tumor model, tumor growth was significantly suppressed in the Ad-CD137L/CAIX vaccine group compared with the single vaccine group. The induction and maturity of CD11C + and CD8 + CD11C + dendritic cell (DC) subsets were promoted in Ad-CD137L/CAIX co-immunized mice. Furthermore, the Ad-CD137L/CAIX vaccine elicited stronger tumor-specific multifunctional CD8 + T cell immune responses as demonstrated by increased proliferation and cytolytic function of CD8 + T cells. Notably, depletion of CD8 + T cells greatly compromised the effective protection provided by Ad-CD137L/CAIX vaccine, suggesting an irreplaceable role of CD8 + T cells for the immunopotency of the vaccine. In both lung metastatic and orthotopic models, Ad-CD137L/CAIX vaccine treatment significantly decreased tumor metastasis and progression and increased the induction of tumor-specific multifunctional CD8 + T cells, in contrast to treatment with the Ad-CAIX vaccine alone. The Ad-CD137L/CAIX vaccine also augmented the tumor-specific multifunctional CD8 + T cell immune response in both orthotopic and metastatic models. These results indicated that Ad-CD137L/CAIX vaccine elicited a potent anti-tumor activity by inducing CD8 + DC-mediated multifunctional CD8 + T cell immune responses. The potential strategy of CD137L-based vaccine might be served as a novel treatment for renal carcinoma or other malignant tumors. Graphical Abstract: ga1 Highlights: Ad-CD137L/CAIX vaccine enhanced the induction and mature of CD11c + DCs and CD8 + CD11c + DCs. Ad-CD137L/CAIX vaccine activated the CD8 + CD11c + DCs mediated tumor-specific multifunctional CD8 + T cell immune responses. Ad-CD137L/CAIX vaccine could inhibit the tumor growth or metastasis in renal cancer models. CD8 + CD11c + DCs-mediated CD8 + T cell responses were required for the anti-tumor immunity by Ad-CD137L/CAIX vaccine.