免疫抑制肿瘤微环境（TME）已成为癌症免疫治疗的主要挑战，丰富的肿瘤相关巨噬细胞（TAM）通过表现出免疫抑制（M2）表型在促进肿瘤免疫逃逸中发挥关键作用。最近有报道称，M1巨噬细胞衍生的纳米囊泡（M1NVs）可以将TAM重编程为抗肿瘤M1表型，从而显着减轻免疫抑制性TME，增强免疫治疗的抗肿瘤疗效。在此，我们开发了负载介孔多巴胺（MPDA）和吲哚菁绿（ICG）的M1NV，这通过协同光热和光动力疗法促进了M2 TAM的募集。此后，M1NVs可以诱导TAMs的M1复极化，导致肿瘤内细胞毒性T淋巴细胞的浸润增加，从而促进肿瘤消退。本研究利用单细胞 RNA 测序 (scRNA-seq) 比较 MPDA/ICG@M1NVs  NIR 治疗前后的 HCC 组织，探讨光疗对肝癌免疫环境的影响。结果显示，细胞组成和基因表达发生显着变化，上皮细胞、B 细胞和巨噬细胞减少，中性粒细胞和骨髓细胞增加。此外，基因分析表明促炎信号和免疫抑制功能减少，同时 B 细胞功能和抗肿瘤免疫增强，MPDA/ICG @M1NVs  NIR 组上皮细胞中 Gtsf1 基因下调，并且lars2 基因在免疫亚群中的表达。 M1 巨噬细胞中 Eno3 表达减少，而 M2 巨噬细胞中 Clec4a3 表达下调。值得注意的是，B 细胞数量减少，而 Pou2f2 表达增加。这些基因调节细胞生长、死亡、代谢和肿瘤环境，表明它们在 HCC 进展中发挥关键作用。这项研究强调了了解细胞和分子动力学以改善免疫治疗的潜力。© 2024。作者。

The immunosuppressive tumor microenvironment (TME) has become a major challenge in cancer immunotherapy, with abundant tumor-associated macrophages (TAMs) playing a key role in promoting tumor immune escape by displaying an immunosuppressive (M2) phenotype. Recently, it was reported that M1 macrophage-derived nanovesicles (M1NVs) can reprogram TAMs to an anti-tumor M1 phenotype, thereby significantly alleviating the immunosuppressive TME and enhancing the anti-tumor efficacy of immunotherapy. Herein, we developed M1NVs loaded with mesoporous dopamine (MPDA) and indocyanine green (ICG), which facilitated the recruitment of M2 TAMs through synergistic photothermal and photodynamic therapy. Thereafter, M1NVs can induce M1 repolarization of TAMs, resulting in increased infiltration of cytotoxic T lymphocytes within the tumor to promote tumor regression. This study investigated the effect of phototherapy on the immune environment of liver cancer using single-cell RNA sequencing (scRNA-seq) by comparing HCC tissues before and after MPDA/ICG@M1NVs + NIR treatment. The results showed significant shifts in cell composition and gene expression, with decreases in epithelial cells, B cells, and macrophages and increases in neutrophils and myeloid cells. Additionally, gene analysis indicated a reduction in pro-inflammatory signals and immunosuppressive functions, along with enhanced B-cell function and anti-tumor immunity, downregulation of the Gtsf1 gene in the epithelial cells of the MPDA/ICG @M1NVs + NIR group, and decreased expression of the lars2 gene in immune subpopulations. Eno3 expression is reduced in M1 macrophages, whereas Clec4a3 expression is downregulated in M2 macrophages. Notably, the B cell population decreased, whereas Pou2f2 expression increased. These genes regulate cell growth, death, metabolism, and tumor environment, indicating their key role in HCC progression. This study highlights the potential for understanding cellular and molecular dynamics to improve immunotherapy.© 2024. The Author(s).