Strategies to enhance cytotoxicity of tumor-infiltrating γδ T-cell subsets against autologous tumor cells

增强肿瘤浸润 γδ T 细胞亚群对自体肿瘤细胞的细胞毒性的策略

• 批准号: 412071939
• 负责人: Professorin Dr. Daniela Wesch
• 金额: --
• 依托单位: Institut für Immunologie
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/412071939?language=en
• 关键词: Strategies; enhance; cytotoxicity; tumor; infiltrating

Localization, distribution, cytotoxicity and activation state of human tumor-infiltrating γδ T cells (γδ TIL) and their impact on survival of cancer patients are of great interest for an improvement of γδ T cell-based immunotherapy. High recurrence rates in epithelial ovarian cancer (EOC) - even after successful initial surgical and poly-chemotherapeutic treatment - reflects a significant problem. Chemotherapeutic standard regimens are often not of long-lasting efficacy in the palliative situation. The presence of intra-tumoral cytotoxic T cells has been correlated with a favorable clinical outcome.Recently, we demonstrated an increased Vγ2,3,4 γδ T-cell infiltration co-expressing Vδ1- or Vδ3-chains in freshly isolated EOC tissue which strongly produce cytotoxic mediators such as granzyme A/B. Further, we discovered a novel role of TNF-related apoptosis-inducing ligand (TRAIL)-receptor 4 that enhance anti-tumoral Vδ1 T-cell cytotoxicity. Since central and effector memory Vδ1 TIL are increased within the EOC tissue, it is likely that they are activated at the tumor-site. The identification of site-specific occurrence of Vγ2,3,4 and Vγ9 γδ T-cell clones and a butyrophilin-dependent activation of Vγ9Vδ1and non-Vδ1/Vδ2 TIL will be investigated within the FOR2799.Our previous results demonstrated that the bispecific T cell engager (bsTCE) [(HER)2xVγ9] enhanced Vγ9 T-cell cytotoxicity against autologous EOC cells expressing the human epidermal growth factor receptor (HER)-2. Further, bsTCE partially overcomes intrinsic tumor resistance mechanisms which prevent γδ T-cell activation. Preliminary results revealed a 30-90% anti-tumor efficacy of [(HER)2xVγ9] in our novel patient-derived ex vivo tumor tissue model including an immunosuppressive tumor microenvironment (TME). Since Vγ2,3,4 TIL accumulate in the EOC tissue, we generated the bsTCE [(HER)2xVγ2,3,4], which allows in combination with [(HER)2xVγ9] to target up to 78% of the γδ TIL in EOC patients. The efficacy of [(HER)2xVγ2,3,4] on γδ T cell-mediated lysis of autologous EOC cells and the impact of the TME will be examined in the NSG mouse model and the patient-derived ex vivo tumor tissue model. The latter is of great use when trying to reduce the translational gap between preclinical and clinical research. The use of the bsTCE in the patient-derived ex vivo tumor tissue model also allows the targeted investigation of the effector function of Vγ2,3,4 and Vγ9 TIL. Since our bsTCEs do not induce γδ T-cell death like repetitive application of phosphorylated antigens does, this is a decisive advantage of bsTCE application. We expect that our bsTCEs reflect a novel tool for a future γδ T cell-based immunotherapy.

人类肿瘤浸润 γδ T 细胞 (γδ TIL) 的定位、分布、细胞毒性和激活状态及其对癌症患者生存的影响对于改进基于 γδ T 细胞的免疫疗法具有重要意义。上皮性卵巢癌（EOC）的高复发率——即使在成功的初始手术和联合化疗治疗之后——反映了一个重大问题。标准化疗方案在姑息治疗中通常不能产生持久疗效。肿瘤内细胞毒性 T 细胞的存在与良好的临床结果相关。最近，我们证明了在新鲜分离的 EOC 组织中共表达 Vδ1 或 Vδ3 链的 Vγ2,3,4 γδ T 细胞浸润增加，这些组织强烈产生细胞毒性介质，例如颗粒酶 A/B。此外，我们还发现了 TNF 相关凋亡诱导配体 (TRAIL) 受体 4 的新作用，可增强抗肿瘤 Vδ1 T 细胞的细胞毒性。由于中枢和效应记忆 Vδ1 TIL 在 EOC 组织内增加，因此它们很可能在肿瘤部位被激活。将在 FOR2799 内研究 Vγ2,3,4 和 Vγ9 γδ T 细胞克隆的位点特异性发生以及 Vγ9Vδ1 和非 Vδ1/Vδ2 TIL 的嗜丁蛋白依赖性激活。我们之前的结果表明，双特异性 T 细胞接合器 (bsTCE) [(HER)2xVγ9] 增强了 Vγ9 T 细胞 对表达人表皮生长因子受体 (HER)-2 的自体 EOC 细胞的细胞毒性。此外，bsTCE 部分克服了阻止 γδ T 细胞激活的内在肿瘤抵抗机制。初步结果显示，在我们的新型患者来源的离体肿瘤组织模型（包括免疫抑制肿瘤微环境 (TME)）中，[(HER)2xVγ9] 的抗肿瘤功效为 30-90%。由于 Vγ2,3,4 TIL 在 EOC 组织中积累，我们生成了 bsTCE [(HER)2xVγ2,3,4]，它与 [(HER)2xVγ9] 组合可以靶向 EOC 患者中高达 78% 的 γδ TIL。 [(HER)2xVγ2,3,4] 对 γδ T 细胞介导的自体 EOC 细胞裂解的功效以及 TME 的影响将在 NSG 小鼠模型和患者来源的离体肿瘤组织模型中进行检查。后者在试图缩小临床前研究和临床研究之间的转化差距时非常有用。在患者来源的离体肿瘤组织模型中使用 bsTCE 还可以对 Vγ2,3,4 和 Vγ9 TIL 的效应器功能进行有针对性的研究。由于我们的 bsTCE 不会像重复应用磷酸化抗原那样诱导 γδ T 细胞死亡，因此这是 bsTCE 应用的决定性优势。我们期望我们的 bsTCE 能够成为未来基于 γδ T 细胞的免疫疗法的新工具。