三维免疫类器官模型评价免疫检查点抑制剂的肿瘤反应。

BACKGROUND: Only 20 percent of renal and bladder cancer patients will show a significant response to immune checkpoint inhibitor (ICI) therapy, and no test currently available accurately predicts ICI response. METHODS: We developed an "immunotumoroid" cell model system that recapitulates the tumor, its microenvironment, and necessary immune system components in patient-derived spheroids to enable ex vivo assessment of tumor response to ICI therapy. Immunotumoroids were developed from surgically resected renal cell carcinomas and bladder carcinomas selected for high tumor-infiltrating lymphocytes (TILs) and survived more than a month without media exchange. Immunohistochemistry was used to detect immune and non-immune cells in cryopreserved source tumors and the resulting immunotumoroids. Immunotumoroid response to ICIs (nivolumab, pembrolizumab, and durvalumab) and chemotherapy (cisplatin, gemcitabine, and paclitaxel) was monitored in real-time with Cytotox Red staining in an Incucyte device, and the immunotumoroid response was compared to retrospective clinical drug responses. RESULTS: Six of the 13 cases tested grew viable immunotumoroid models, with failed cases attributed to extensive tumor tissue necrosis or excess lymphocytes preventing spheroid formation. One successfully cultured case was excluded from the study due to low TIL infiltration (<5%) in the primary tumor sample. The five remaining models contained immune cells (CD4+ and CD8+ T cells, and macrophages), non-immune cells (fibroblasts), and tumor cells. Chemotherapy and ICI drugs were tested in immunotumoroids from 5 cases and compared to clinical outcomes where data was available. Four/five models showed cell killing in response to chemotherapy and two/five showed sensitivity to ICI. In three cases, the immunotumoroid model accurately predicted the patient's clinical response or non-response to ICIs or chemotherapy. CONCLUSION: Our immunotumoroid model replicated the multicellular nature of the tumor microenvironment sufficiently for preclinical ICI screening. This model could enable valuable insights into the complex interactions between cancer cells, the immune system, and the microenvironment. This is a feasibility study on a small number of cases, and additional studies with larger case numbers are required including correlation with clinical response.

背景：只有 20%的肾和膀胱癌患者对免疫检查点抑制剂（ICI）治疗有明显反应，目前尚无准确预测 ICI 反应的检测方法。

方法：我们开发了一种“免疫类器官”细胞模型系统，该系统可在患者来源的球体中重现肿瘤、其微环境和必要的免疫系统成分，从而能够体外评估肿瘤对 ICI 治疗的反应。免疫类器官是从手术切除的肾细胞癌和膀胱癌中开发的，这些肿瘤选择了高肿瘤浸润淋巴细胞（TIL），并且在没有介质交换的情况下存活了一个多月。免疫组化用于检测冷冻源肿瘤和由此产生的免疫类器官中免疫和非免疫细胞。在 Incucyte 设备中使用 Cytotox Red 染色实时监测免疫类器官对 ICI（nivolumab、pembrolizumab 和 durvalumab）和化疗（顺铂、吉西他滨和紫杉醇）的反应，并将免疫类器官的反应与回顾性临床药物反应进行比较。

结果：在测试的 13 例中，有 6 例成功培养出有活力的免疫类器官模型，失败的原因是肿瘤组织坏死广泛或过多的淋巴细胞阻止了球体的形成。由于原发性肿瘤样本中 TIL 浸润率（<5%）低，一个成功培养的病例被排除在研究之外。其余 5 个模型包含免疫细胞（CD4+和 CD8+T 细胞和巨噬细胞）、非免疫细胞（成纤维细胞）和肿瘤细胞。对来自 5 例的免疫类器官进行了化疗和 ICI 药物测试，并与可获得数据的临床结果进行了比较。在 4/5 例模型中，细胞对化疗有杀伤作用，在 2/5 例模型中，细胞对 ICI 敏感。在 3 例中，免疫类器官模型准确预测了患者对 ICI 或化疗的临床反应或无反应。

结论：我们的免疫类器官模型充分复制了肿瘤微环境的多细胞特性，足以进行 ICI 的临床前筛选。该模型可以为深入了解癌细胞、免疫系统和微环境之间的复杂相互作用提供有价值的见解。这是一项对少数病例进行的可行性研究，需要进行更多的包括与临床反应相关的包括更大病例数量的研究。