多发性骨髓瘤（MM）是一种具有优先骨髓（BM）趋向性的浆细胞疾病。组织特异性趋化因子受体的强制表达已被证明可以成功引导过继转移的 CAR NK 细胞进入实体癌的恶性环境，同时也引导 BM 驻留的 AML 和 MM。为了重定向至 BM 相关趋化因子 CXCL12，我们用野生型 CXCR4 或功能获得性突变体 CXCR4R334X 的异位表达来武装 BCMA CAR-NK-92 以及原代 NK 细胞。我们的数据显示，配备 CXCR4 的 BCMA CAR-NK-92 和原代 NK 细胞在体外向 CXCL12 迁移的能力得到了改善。除了协调趋化性的经典作用外，CXCR4 还被证明参与 T 细胞共刺激，这促使我们检查 CXCR4 共转导的 BCMA-CAR NK 细胞的功能。异位 CXCR4 表达增强了 BCMA CAR-NK 细胞的细胞毒能力，这一点可以通过体外消除表达 BCMA 的靶细胞系和原代 MM 细胞以及通过加速溶细胞颗粒释放的能力来证明。我们表明，CXCR4 共修饰延长了 BCMA CAR 表面沉积，增强了 CAR 接合后 ZAP-70 的募集，并加速了远端信号转导动力学。 BCMA CAR 对抗原的敏感性通过增强 ZAP-70 向免疫突触的募集而增强，这表明 CXCR4 过表达时 CAR 被触发的倾向增加。出乎意料的是，在没有 CXCL12 配体刺激的情况下，通过 CXCR4 进行了共刺激。总的来说，我们的研究结果表明，CAR-NK 细胞与组织相关趋化因子受体的共修饰不仅会改善肿瘤部位内的运输和保留，还会影响过继性 NK 细胞治疗。版权所有 © 2024 Moles、Erdlei、Menzel、Massaro、Fiori、Bunse、Schrimpf 、Gerlach、Gudipati、Reiser、Mathavan、Goodrich、Huppa、Krönke、Valamehr、Höpken 和 Rehm。

Multiple myeloma (MM) is a plasma cell disease with a preferential bone marrow (BM) tropism. Enforced expression of tissue-specific chemokine receptors has been shown to successfully guide adoptively-transferred CAR NK cells towards the malignant milieu in solid cancers, but also to BM-resident AML and MM. For redirection towards BM-associated chemokine CXCL12, we armored BCMA CAR-NK-92 as well as primary NK cells with ectopic expression of either wildtype CXCR4 or a gain-of-function mutant CXCR4R334X. Our data showed that BCMA CAR-NK-92 and -primary NK cells equipped with CXCR4 gained an improved ability to migrate towards CXCL12 in vitro. Beyond its classical role coordinating chemotaxis, CXCR4 has been shown to participate in T cell co-stimulation, which prompted us to examine the functionality of CXCR4-cotransduced BCMA-CAR NK cells. Ectopic CXCR4 expression enhanced the cytotoxic capacity of BCMA CAR-NK cells, as evidenced by the ability to eliminate BCMA-expressing target cell lines and primary MM cells in vitro and through accelerated cytolytic granule release. We show that CXCR4 co-modification prolonged BCMA CAR surface deposition, augmented ZAP-70 recruitment following CAR-engagement, and accelerated distal signal transduction kinetics. BCMA CAR sensitivity towards antigen was enhanced by virtue of an enhanced ZAP-70 recruitment to the immunological synapse, revealing an increased propensity of CARs to become triggered upon CXCR4 overexpression. Unexpectedly, co-stimulation via CXCR4 occurred in the absence of CXCL12 ligand-stimulation. Collectively, our findings imply that co-modification of CAR-NK cells with tissue-relevant chemokine receptors affect adoptive NK cell therapy beyond improved trafficking and retention within tumor sites.Copyright © 2024 Moles, Erdlei, Menzel, Massaro, Fiori, Bunse, Schrimpf, Gerlach, Gudipati, Reiser, Mathavan, Goodrich, Huppa, Krönke, Valamehr, Höpken and Rehm.