Natural killer (NK) cells eliminate infected or cancer cells via their cytotoxic capacity. NKG2A is an inhibitory receptor on NK cells and cancer cells often overexpress its ligand HLA-E to evade NK cell surveillance. Given the successes of immune checkpoint blockade in cancer therapy, NKG2A is an interesting novel target. However, anti-NKG2A antibodies have shown limited clinical response. In the pursuit of enhancing NK cell-mediated anti-tumor responses, we devised a Cas9-based strategy to delete , encoding NKG2A, in human primary NK cells. Our approach involved electroporation of -targeting Cas9 ribonucleoprotein resulting in effective ablation of NKG2A expression. Compared with anti-NKG2A antibody blockade, NKG2A NK cells exhibited enhanced activation, reduced suppressive signaling, and elevated expression of key transcription factors. NKG2A NK cells overcame inhibition from HLA-E, significantly boosting NK cell activity against solid and hematologic cancer cells. We validated this efficacy across multiple cell lines, a xenograft mouse model, and primary human leukemic cells. Combining NKG2A knockout with antibody coating of tumor cells further enhanced cytotoxicity through ADCC. Thus, we provide a comprehensive comparison of inhibition of the NKG2A pathway using genetic ablation and antibodies and provide novel insight in the observed differences in molecular mechanisms, which can be translated to enhance adoptive NK cell immunotherapy.

中文翻译：

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NKG2A 基因缺失比抗 NKG2A 单克隆抗体更能促进人原代 NK 细胞抗肿瘤反应


自然杀伤 (NK) 细胞通过其细胞毒性能力消除感染细胞或癌细胞。 NKG2A 是 NK 细胞的抑制性受体，癌细胞经常过度表达其配体 HLA-E 以逃避 NK 细胞监视。鉴于免疫检查点阻断在癌症治疗中取得的成功，NKG2A 是一个有趣的新靶点。然而，抗 NKG2A 抗体的临床反应有限。为了增强 NK 细胞介导的抗肿瘤反应，我们设计了一种基于 Cas9 的策略来删除人类原代 NK 细胞中编码 NKG2A 的 。我们的方法涉及靶向 Cas9 核糖核蛋白的电穿孔，从而有效消除 NKG2A 表达。与抗 NKG2A 抗体阻断相比，NKG2A NK 细胞表现出增强的激活、减少的抑制信号传导以及关键转录因子的表达升高。 NKG2A NK 细胞克服了 HLA-E 的抑制，显着增强了 NK 细胞对抗实体癌细胞和血液癌细胞的活性。我们在多个细胞系、异种移植小鼠模型和原代人类白血病细胞中验证了这种功效。将 NKG2A 敲除与肿瘤细胞的抗体涂层相结合，通过 ADCC 进一步增强细胞毒性。因此，我们对使用基因消融和抗体抑制 NKG2A 通路进行了全面比较，并为观察到的分子机制差异提供了新的见解，这可以转化为增强过继性 NK 细胞免疫治疗。