肝细胞癌 (HCC) 经常因微小残留病 (MRD) 复发，且在治疗后仍持续存在。在这里，我们使用化疗栓塞后人类 HCC（n = 108 名患者，107 万个细胞）和 MRD 转基因小鼠模型确定了残留肿瘤细胞持续存在的机制。通过单细胞高重细胞计数成像，我们确定了一个空间邻域，其中 PD-L1  M2 样巨噬细胞与干细胞样肿瘤细胞相互作用，与 CD8 T 细胞耗竭和生存不良相关。此外，通过残留 HCC 的空间转录组学，我们发现巨噬细胞来源的 TGFβ1 介导干细胞样肿瘤细胞的持续存在。最后，我们证明在两种小鼠模型中联合阻断 Pdl1 和 Tgfβ 可以排除免疫抑制性巨噬细胞，招募活化的 CD8 T 细胞并消除残留的干细胞样肿瘤细胞：MRD 转基因模型和多柔比星耐药 HCC 的同基因原位模型。因此，我们的空间分析表明，PD-L1 巨噬细胞通过激活干细胞样癌细胞中的 TGFβ 通路来维持 MRD，并针对这种相互作用可以预防 MRD 导致的 HCC 复发。© 2024。作者，获得 Springer Nature 独家许可美国公司

Hepatocellular carcinoma (HCC) frequently recurs from minimal residual disease (MRD), which persists after therapy. Here, we identified mechanisms of persistence of residual tumor cells using post-chemoembolization human HCC (n = 108 patients, 1.07 million cells) and a transgenic mouse model of MRD. Through single-cell high-plex cytometric imaging, we identified a spatial neighborhood within which PD-L1 + M2-like macrophages interact with stem-like tumor cells, correlating with CD8+ T cell exhaustion and poor survival. Further, through spatial transcriptomics of residual HCC, we showed that macrophage-derived TGFβ1 mediates the persistence of stem-like tumor cells. Last, we demonstrate that combined blockade of Pdl1 and Tgfβ excluded immunosuppressive macrophages, recruited activated CD8+ T cells and eliminated residual stem-like tumor cells in two mouse models: a transgenic model of MRD and a syngeneic orthotopic model of doxorubicin-resistant HCC. Thus, our spatial analyses reveal that PD-L1+ macrophages sustain MRD by activating the TGFβ pathway in stem-like cancer cells and targeting this interaction may prevent HCC recurrence from MRD.© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.