新辅助免疫检查点阻断（ICB）联合放化疗可为局部晚期食管鳞状细胞癌（ESCC）患者提供较高的病理完全缓解（pCR）率。但这种新辅助治疗调节的动态肿瘤免疫微环境仍不清楚。 总共招募了 41 名局部晚期 ESCC 患者。所有患者均接受新辅助特瑞普利单抗联合同步放化疗。获得匹配的治疗前和治疗后组织用于荧光多重免疫组织化学 (mIHC) 和 IHC 分析。免疫细胞的密度和空间分布由 HALO 模块确定。考察新辅助治疗前后免疫细胞模式的差异。在治疗前组织中，与切除淋巴结（pN1）中存在残余肿瘤的患者相比，治疗前组织中观察到更多的间质CD3  FoxP3  Tregs和CD86/CD163 巨噬细胞。 pCR 患者。 pN1 患者中大多数巨噬细胞分布在肿瘤巢附近。在治疗后的组织中，pCR患者的CD86 细胞浸润较少，而非pCR患者的CD86 细胞密度较高与较高的肿瘤消退等级（TRG）显着相关。当比较配对的治疗前和治疗后样本时，发现了与治疗相关的异质性免疫细胞模式。治疗后，pCR患者的CD3  T淋巴细胞略有增加，但非pCR患者的CD3  T淋巴细胞明显减少。相比之下，非pCR和pCR患者的CD86 细胞浸润分别显着增加和不太明显减少。此外，在pN0和pN1患者之间观察到治疗引起的CD8  和CD15  细胞浸润变化的相反趋势。总的来说，我们的数据展示了ESCC新辅助ICB联合放化疗前后肿瘤免疫状况的全面图景。 CD86 巨噬细胞的浸润可能作为新辅助特瑞普利单抗联合放化疗的不利指标。© 2024。作者。

Neoadjuvant immune checkpoint blockade (ICB) combined with chemoradiotherapy offers high pathologic complete response (pCR) rate for patients with locally advanced esophageal squamous cell carcinomas (ESCC). But the dynamic tumor immune microenvironment modulated by such neoadjuvant therapy remains unclear.A total of 41 patients with locally advanced ESCC were recruited. All patients received neoadjuvant toripalimab combined with concurrent chemoradiotherapy. Matched pre- and post-treatment tissues were obtained for fluorescent multiplex immunohistochemistry (mIHC) and IHC analyses. The densities and spatial distributions of immune cells were determined by HALO modules. The differences of immune cell patterns before and after neoadjuvant treatment were investigated.In the pre-treatment tissues, more stromal CD3 + FoxP3 + Tregs and CD86+/CD163 + macrophages were observed in patients with residual tumor existed in the resected lymph nodes (pN1), compared with patients with pCR. The majority of macrophages were distributed in close proximity to tumor nest in pN1 patients. In the post-treatment tissues, pCR patients had less CD86 + cell infiltration, whereas higher CD86 + cell density was significantly associated with higher tumor regression grades (TRG) in non-pCR patients. When comparing the paired pre- and post-treatment samples, heterogeneous therapy-associated immune cell patterns were found. Upon to the treatment, CD3 + T lymphocytes were slightly increased in pCR patients, but markedly decreased in non-pCR patients. In contrast, a noticeable increase and a less obvious decrease of CD86 + cell infiltration were respectively depicted in non-pCR and pCR patients. Furthermore, opposite trends of the treatment-induced alterations of CD8 + and CD15 + cell infiltrations were observed between pN0 and pN1 patients.Collectively, our data demonstrate a comprehensive picture of tumor immune landscape before and after neoadjuvant ICB combined with chemoradiotherapy in ESCC. The infiltration of CD86 + macrophage may serve as an unfavorable indicator for neoadjuvant toripalimab combined with chemoradiotherapy.© 2024. The Author(s).