Seidel Ursula Jördis Eva, Vogt Fabian, Grosse-Hovest Ludger, Jung Gundram, Handgretinger Rupert, Lang Peter
Department of General Paediatrics, Oncology/Haematology, University Children's Hospital Tübingen , Tübingen , Germany.
Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen , Tübingen , Germany ; Partner Site Tübingen, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ) , Tübingen , Germany.
Front Immunol. 2014 Dec 2;5:618. doi: 10.3389/fimmu.2014.00618. eCollection 2014.
γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc-optimized CD19 antibody (4G7SDIE) and a bi-specific antibody with the specificities CD19 and CD16 (N19-C16) was evaluated in CD107a-degranulation assays and intracellular cytokine staining. CD107a, TNFα, and IFNγ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system) measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits a promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and requires clinical evaluation.
γδ T细胞不受主要组织相容性复合体（MHC）限制，可对多种恶性肿瘤产生细胞毒性，在新型干细胞移植策略的移植后早期阶段存在，并且已证明可与单克隆抗体（mAb）介导抗体依赖性细胞毒性（ADCC）。这些特性使γδ T细胞成为B系急性淋巴细胞白血病（ALL）儿科患者基于抗体的免疫治疗中有前景的效应细胞。为了评估人γδ T细胞与CD19抗体联合用于B系ALL的免疫治疗，按照符合药品生产质量管理规范（GMP）的方案扩增γδ T细胞，并在CD107a脱颗粒试验和细胞内细胞因子染色中评估原代和扩增的γδ T细胞与Fc优化的CD19抗体（4G7SDIE）和具有CD19和CD16特异性的双特异性抗体（N19-C16）的ADCC。原代γδ T细胞的CD107a、肿瘤坏死因子α（TNFα）和干扰素γ（IFNγ）表达显著增加，且与γδ T细胞的CD16表达相关。扩增后γδ T细胞高表达CD107a，未检测到4G7SDIE和N19-C16使其表达进一步增加。在铕-TDA释放试验和基于阻抗的无标记方法（使用xCELLigence系统）中评估纯化的扩增γδ T细胞对表达CD19细胞的细胞毒性，实时测量γδ T细胞裂解。尽管在2小时终点铕-TDA释放试验中未观察到裂解增加，但在实时xCELLigence试验中观察到γδ T细胞显著的非抗体依赖性细胞毒性和ADCC。xCELLigence系统在灵敏度方面优于终点铕-TDA释放试验，并允许得出关于γδ T细胞在较长时间段内裂解动力学的结论。CD19抗体与原代以及扩增的γδ T细胞联合表现出一种有前景的方法，这可能改善儿科B系ALL患者的临床结局，需要进行临床评估。
