重塑肿瘤微环境是治疗晚期肝细胞癌（HCC）的关键策略。然而，目前我们对于微环境中的不同细胞群体如何介导肿瘤对抗抗-PD-1免疫治疗的过程尚知之甚少。我们通过单细胞分辨率对HCC患者的肿瘤组织进行转录组分析，这些患者预定接受以抗-PD-1为基础的免疫治疗。我们的比较分析和流式细胞术以及组织病理学分析的实验证实揭示了一种与抗-PD-1治疗耐药性相关的离散细胞亚群，包括HCC患者和大鼠模型。我们还采用基于TurboID的近源标记方法来获得对HCC微环境重编程机制的深入认识。 在这里，我们发现特异性的CD10+ALPL+ NEU细胞与抗-PD-1治疗耐药性相关。这些NEU细胞表现出强烈的免疫抑制活性，能够引起T细胞数量、频率和基因表达谱方面的明显“不可逆性”耗竭。机制上，特异性的CD10+ALPL+ NEU细胞由肿瘤细胞诱导，即肿瘤分泌的NAMPT通过NTRK1重新编程CD10+ALPL+ NEU细胞，维持其未成熟状态并抑制CD10+ALPL+ NEU细胞的成熟和激活。 总体而言，我们的结果揭示了涉及CD10+ALPL+ NEU细胞的肿瘤免疫逃逸机制，即逃避持久的抗-PD-1治疗，并进一步提供了免疫治疗靶点或抗-PD-1协同治疗方案的更多见解。在这里，我们发现肿瘤细胞通过重编程CD10+ALPL+ NEU细胞诱导了T细胞的“不可逆性”耗竭，从而使肿瘤逃避了抗-PD-1治疗的预期效果。我们的数据为阐明特殊细胞群体和抗免疫治疗耐药性的分子机制提供了新的理论基础。针对这些细胞的靶向治疗有助于评估免疫治疗适应证，并可能成为一种更有效的治疗方法。 版权所有 © 2023 Elsevier B.V. 出版。

Remodeling the tumor microenvironment is a critical strategy for treating advanced hepatocellular carcinoma (HCC). Yet it remains poorly understood how distinct cell populations in the microenvironment mediate tumor resistance to immunotherapy such as anti-PD-1.We analyzed the transcriptomic profiling at a single-cell resolution within tumor tissues from HCC patients scheduled to receive anti-PD-1-based immunotherapy. Our comparative analysis and experimental validation using flow cytometry and histopathological analysis uncovered a discrete subpopulation of cells associated with resistance to anti-PD-1 treatment in HCC patients and a rat model. A TurboID-based proximity labeling approach was deployed to gain mechanistic insights into the reprogramming of the HCC microenvironment.Here, we found specifically CD10+ALPL+ NEUs to be associated with resistance to anti-PD-1 treatment. These NEUs exhibited a strong immunosuppressive activity of inducing an apparent "irreversible" exhaustion of T cells in terms of cell number, frequency, and gene profile. Mechanistically, specifically CD10+ALPL+ NEUs were induced by tumor cells, i.e., tumor-secreted NAMPT reprogrammed CD10+ALPL+ NEUs through NTRK1, maintaining the immature state and inhibiting the maturation and activation of CD10+ALPL+ NEUs.Collectively, our results revealed a fundamental mechanism involving CD10+ALPL+ NEUs for tumor immune escape from durable anti-PD-1 treatment and provided further insights into immunotherapy targets or anti-PD-1 synergistic treatment regimens.Herein, we discovered that tumor cells reprogrammed CD10+ALPL+ NEUs to induce the "irreversible" exhaustion of T cells and hence allow the tumors to escape from the intended effects of anti-PD-1 treatment. Our data provided a new theoretical basis for the elucidation of special cell populations and a molecular mechanism underpinning resistance to immunotherapy. Targeting these cells contributed to evaluating indications for immunotherapy and could be looked at as a potentially more effective therapeutic approach.Copyright © 2023. Published by Elsevier B.V.