抗 PD-L1 抗体通过抗体依赖性细胞介导的细胞毒性介导肝细胞癌中 PD-L1(high)CD11b(+) 细胞清除，增强冷冻消融的疗效

Cryoablation (CRA) and microwave ablation (MWA) are two main local treatments for hepatocellular carcinoma (HCC).

However, which one is more curative and suitable for combining with immunotherapy is still controversial.

Herein, CRA induced higher tumoral PD-L1 expression and more T cells infiltration, but less PD-L1 high CD11b + myeloid cells infiltration than MWA in HCC.

Furthermore, CRA had better curative effect than MWA for anti-PD-L1 combination therapy in mouse models.

Mechanistically, anti-PD-L1 antibody facilitated infiltration of CD8 + T cells by enhancing the secretion of CXCL9 from cDC1 cells after CRA therapy. On the other hand, anti-PD-L1 antibody promoted the infiltration of NK cells to eliminate PD-L1 high CD11b + myeloid cells by antibody-dependent cell-mediated cytotoxicity (ADCC) effect after CRA therapy. Both aspects relieved the immunosuppressive microenvironment after CRA therapy.

Notably, the wild-type PD-L1 Avelumab (Bavencio), compared to the mutant PD-L1 atezolizumab (Tecentriq), was better at inducing the ADCC effect to target PD-L1 high CD11b + myeloid cells. Collectively, our study uncovered the novel insights that CRA showed superior curative effect than MWA in combining with anti-PD-L1 antibody by strengthening CTL/NK cell immune responses, which provided a strong rationale for combining CRA and PD-L1 blockade in the clinical treatment for HCC.