非小细胞肺癌（NSCLC）是全球导致癌症相关死亡的主要原因。本研究评估了经视频辅助胸腔镜淋巴清扫术（VAMLA）完全清除纵隔淋巴结对NSCLC患者自然杀伤（NK）细胞表型和功能的影响。研究包括21例接受VAMLA分期的NSCLC患者（cIA-IVA）和33名健康对照者。我们从所有参与者的外周血和患者的纵隔淋巴结中分离出单个核细胞。采用流式细胞术分析NK细胞亚群、PD-1、CTLA-4、激活/抑制受体、粒胞酶A和CD107a的表达。采用ELISA法测定可溶性PD-1、PDL-1和CTLA-4的血浆水平。NSCLC患者的纵隔淋巴结中出现了疲劳的NK细胞比例增加、PD-1和IL-10表达增加，以及细胞毒性受损。纵隔淋巴结切除增加了CD56dimCD16bright细胞毒性效应的表型，并减少了疲劳的NK细胞。PD-1+ NK细胞在患者的血液中明显增多，而VAMLA明显降低了其比例。经VAMLA后，分泌IL-10的调节性NK细胞比例也减少。血液NK细胞的细胞毒性功能和自发性IFN-γ分泌增加，而这些NK细胞功能也被VAMLA恢复了。纵隔淋巴结的切除逆转了NK细胞疲劳，减少了调节性NK细胞，并改善了NK细胞的抗肿瘤功能。肿瘤引流淋巴结可能有助于肿瘤逃避抗肿瘤免疫应答。有关切除它们的作用需要进一步研究，以更好地了解这个机制，并作为潜在的免疫治疗方法的一部分进行研究。© 2023。作者（们），在Springer Science+Business Media, LLC的专属许可下，属Springer Nature的一部分。

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death globally. In this study, the effect of complete removal of mediastinal lymph nodes by video-assisted mediastinoscopic lymphadenectomy (VAMLA) on natural killer (NK) cell phenotype and functions in patients with NSCLC was evaluated. The study included 21 NSCLC patients (cIA-IVA) undergoing VAMLA staging and 33 healthy controls. Mononuclear cells were isolated from peripheral blood of all participants and mediastinal lymph nodes of the patients. NK cells were analyzed by flow cytometry to define NK subsets, expressions of PD-1, CTLA-4, activating/inhibitory receptors, granzyme A, and CD107a. The plasma levels of soluble PD-1, PDL-1, and CTLA-4 were measured by ELISA. Mediastinal lymph nodes of NSCLC patients had increased ratios of exhausted NK cells, increased expression of PD-1 and IL-10, and impaired cytotoxicity. Mediastinal lymph nodes removal increased CD56dimCD16bright cytotoxic effector phenotype and reduced exhausted NK cells. PD-1+ NK cells were significantly more abundant in patients' blood, and VAMLA significantly reduced their ratio as well. The ratio of IL-10 secreting regulatory NK cells was also reduced after VAMLA. Blood NK cells had increased cytotoxic functions and spontaneous IFN-γ secretion, and these NK cell functions were also recovered by VAMLA. Mediastinal lymph node removal reversed NK cell exhaustion, reduced regulatory NK cells, and improved antitumoral functions of NK cells. Tumor-draining lymph nodes may contribute to tumor evasion from antitumoral immune responses. The role of their removal needs to be further studied both to better understand this mechanism and as a potential immunotherapeutic approach.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.