肿瘤细胞治疗研究
英文原题：Engineering CAR-NK cells to secrete IL-15 sustains their anti-AML functionality but is associated with systemic toxicities.
CD123-CAR和sIL-15的转基因表达使NK细胞能够在慢性抗原暴露的情况下发挥作用，但与全身毒性相关。因此，我们的研究为推动在开展早期临床测试之前探索可诱导和可控的表达系统，以向AML特异性CAR-NK细胞提供细胞因子信号提供了动力。
复发/难治性急性髓系白血病（AML）患者的预后仍然很差，基于细胞的免疫疗法有望改善结局。自然杀伤（NK）细胞可通过一组与AML表面配体结合的活化受体引发抗白血病反应。NK细胞过继转移是安全的，但迄今显示出的抗AML疗效有限。在此，我们旨在通过工程化改造NK细胞以表达嵌合抗原受体（CAR）来增强其抗AML活性，并表达白细胞介素（IL）-15以增强其持久性，从而克服这一局限。
我们在体外和AML异种移植模型中详细表征了表达一组AML（CD123）特异性CAR和/或IL-15的NK细胞群体。
携带2B4或4-1BB信号结构域的CAR在细胞表面表达更高，并赋予NK细胞更强的体外抗AML活性。初步体内试验显示，与未转导（UTD）和4-1BB CAR-NK细胞相比，只有2B4嵌合抗原受体（CAR）-NK细胞具有更强的抗AML活性。然而，由于CAR-NK细胞持久性有限，这种获益是短暂的。在2B4 CAR和UTD NK细胞中转基因表达分泌型白细胞介素（sIL）-15可在体外慢性抗原刺激条件下改善其效应功能。慢性抗原暴露后的多参数流式分析识别出独特NK细胞亚群的扩增。2B4/sIL-15 CAR和sIL-15 NK细胞维持了整体活化的NK细胞表型。转录组分析证实了这一点，显示这些NK细胞组具有高度增殖和活化的特征。在体内，2B4/sIL-15 CAR-NK细胞在一个模型中具有强效抗AML活性，而2B4/sIL-15 CAR和sIL-15 NK细胞在第二个模型中诱导了致死性毒性。
BACKGROUND: The prognosis of patients with recurrent/refractory acute myelogenous leukemia (AML) remains poor and cell-based immunotherapies hold promise to improve outcomes. Natural Killer (NK) cells can elicit an antileukemic response via a repertoire of activating receptors that bind AML surface ligands. NK-cell adoptive transfer is safe but thus far has shown limited anti-AML efficacy. Here, we aimed to overcome this limitation by engineering NK cells to express chimeric antigen receptors (CARs) to boost their anti-AML activity and interleukin (IL)-15 to enhance their persistence. METHODS: We characterized in detail NK-cell populations expressing a panel of AML (CD123)-specific CARs and/or IL-15 in vitro and in AML xenograft models. RESULTS: CARs with 2B4. or 4-1BB. signaling domains demonstrated greater cell surface expression and endowed NK cells with improved anti-AML activity in vitro. Initial in vivo testing revealed that only 2B4. Chimeric Antigen Receptor (CAR)-NK cells had improved anti-AML activity in comparison to untransduced (UTD) and 4-1BB. CAR-NK cells. However, the benefit was transient due to limited CAR-NK-cell persistence. Transgenic expression of secretory interleukin (sIL)-15 in 2B4. CAR and UTD NK cells improved their effector function in the setting of chronic antigen simulation in vitro. Multiparameter flow analysis after chronic antigen exposure identified the expansion of unique NK-cell subsets. 2B4. /sIL-15 CAR and sIL-15 NK cells maintained an overall activated NK-cell phenotype. This was confirmed by transcriptomic analysis, which revealed a highly proliferative and activated signature in these NK-cell groups. In vivo, 2B4. /sIL-15 CAR-NK cells had potent anti-AML activity in one model, while 2B4. /sIL-15 CAR and sIL-15 NK cells induced lethal toxicity in a second model. CONCLUSION: Transgenic expression of CD123-CARs and sIL-15 enabled NK cells to function in the setting of chronic antigen exposure but was associated with systemic toxicities. Thus, our study provides the impetus to explore inducible and controllable expression systems to provide cytokine signals to AML-specific CAR-NK cells before embarking on early-phase clinical testing.
MEMBER ACCOUNT
登录成功会直接打开下一页。
