Jin Yining, Jia Zhiliang, Xia Xueqing, Gordon Nancy B, Ludwig Joseph A, Somaiah Neeta, Li Shulin
Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
Department of Sarcoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
Front Immunol. 2025 Mar 12;16:1557006. doi: 10.3389/fimmu.2025.1557006. eCollection 2025.
Tumor infiltrating lymphocytes (TILs) therapy has been proved for treatment of metastatic melanoma and is under investigation for other types of solid tumors. However, these successes are threatened by discontinued supply of GMP-grade anti-CD137 agonist, a key TIL preparation reagent. Therefore, exploring a GMP-adherent method for expanding endogenous TILs without anti-CD137 agonist is urgent. Toward this end, we aimed to establish an anti-CD137-independent and clinically feasible TIL expansion protocol to prepare TILs from under investigated sarcoma tumors.
We collected resected tumors from patients and cut tissues into fragments. We used IL-2 and T-cell activator CD3/CD28 without anti-CD137 agonist to expand nonselected TILs in 2-3 weeks, then rapidly expanded them over 2 weeks. Their phenotypes were characterized using flow cytometry. Their antitumor activity was validated using cytotoxic T lymphocyte assays measuring CD107a on the TILs and the viability of tumor cells and using an autologous patient-derived xenograft (PDX) tumor model.
We successfully expanded TILs in > 90% of collected samples. TILs generated preferentially increased CD8+ T cells but suppressed CD4+ T cells. A small portion of TILs were resident memory T cells. The expanded TILs reduced autologous tumor cells by 37.5% within 24 hours. Infusion of TILs in mice bearing autologous PDX tumors strongly inhibited liposarcoma growth. FDA has approved use of this GMP-feasible protocol in our clinical trial (IND 30562).
It is feasible to generate antitumor TILs using CD3/CD28 activator to replace the unavailable anti-CD137 agonist. Our study supports the further development of TIL-based therapy.
肿瘤浸润淋巴细胞（TILs）疗法已被证明可用于治疗转移性黑色素瘤，目前正在对其他类型的实体瘤进行研究。然而，这些成功受到关键TIL制备试剂GMP级抗CD137激动剂供应中断的威胁。因此，迫切需要探索一种不使用抗CD137激动剂来扩增内源性TILs的符合GMP标准的方法。为此，我们旨在建立一种不依赖抗CD137且临床可行的TIL扩增方案，以便从正在研究的肉瘤肿瘤中制备TILs。
我们收集了患者切除的肿瘤，并将组织切成碎片。我们使用白细胞介素-2和T细胞激活剂CD3/CD28（不使用抗CD137激动剂）在2至3周内扩增未筛选的TILs，然后在2周内快速扩增它们。使用流式细胞术对它们的表型进行表征。使用细胞毒性T淋巴细胞测定法（测量TILs上的CD107a以及肿瘤细胞的活力）和使用患者来源的自体异种移植（PDX）肿瘤模型来验证它们的抗肿瘤活性。
我们在超过90%的收集样本中成功扩增了TILs。产生的TILs优先增加了CD8 + T细胞，但抑制了CD4 + T细胞。一小部分TILs是驻留记忆T细胞。扩增的TILs在24小时内使自体肿瘤细胞减少了37.5%。将TILs注入携带自体PDX肿瘤的小鼠中可强烈抑制脂肪肉瘤的生长。美国食品药品监督管理局已批准在我们的临床试验（IND 30562）中使用这种符合GMP标准的方案。
使用CD3/CD28激活剂替代无法获得的抗CD137激动剂来产生抗肿瘤TILs是可行的。我们的研究支持基于TIL的疗法的进一步发展。
