Role and therapeutic modulation of the RANK-RANKL molecule system in the NK cell immune surveillance of malignant hematopoietic diseases

RANK-RANKL分子系统在恶性造血疾病NK细胞免疫监视中的作用和治疗调节

• 批准号: 205985315
• 负责人: Professor Dr. Helmut Rainer Salih
• 金额: --
• 依托单位: Klinische Kooperationseinheit Translationale Immunologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/205985315?language=en
• 关键词: Role; therapeutic; modulation; RANK; RANKL

NK cells play an important role in the immunosurveillane of tumors and, due to their ability to potently mediate antibody-dependent cellular cytotoxicity (ADCC), largely contribute to the clinical efficacy of therapeutic antibodies like Rituximab. Accordingly, multiple strategies presently aim to increase the potential of antibodies to induce ADCC of NK cells against tumor cells. Both the direct anti-tumor reactivity and ADCC of NK cells are influenced by the various ligands for receptors expressed by NK cells, and neutralization of inhibitory molecules thus serves well to increase constitutive and therapeutically-induced NK cell anti-tumor immunity. In the last funding period we demonstrated that the TNFR family member RANK (mainly known for its role in bone metabolism) is expressed by NK cells while its counterpart RANKL is expressed by malignant hematopoietic cells. We found that RANKL is capable to transduce signals into the ligand-expressing malignant cells (reverse signaling) which lead to release of cytokines that act as autocrine/paracrine growth and survival factors in the malignant diseases. In addition, the factors released upon RANKL signaling impaired the anti-tumor reactivity of NK cells and induced RANK expression on NK cells, The latter was further found to transduce signals into NK cells that impair their anti-tumor reactivity thereby facilitating immune escape of the RANKL-expressing malignant cells. Based on these findings we developed Fc-engineered RANK-Ig fusion proteins that are capable to neutralize the detrimental function of RANKL on anti-tumor immunity while at the same time potently stimulating NK cell ADCC by targeting of the malignant cells.In the second funding period we aim to elucidate the signaling pathways that mediate the induction of cytokine release and metabolic activity in malignant hematopoietic cells following RANKL signaling. Moreover, we aim to determine the molecular mechanisms by which RANK mediates the observed differential inhibition of NK cell cytotoxicity and cytokine production. Based on our findings regarding the differential susceptibility of human and murine NK cells for ADCC-induction observed in syngeneic mouse tumor models, the focus of the upcoming studies is to establish suitable humanized mouse models to further preclinically characterize our Fc-engineered RANK-Ig fusion proteins. Such models are envisaged to finally validate our strategy to dually reinforce NK reactivity against malignant hematopoietic cells by neutralizing the inhibitory effects of RANKL and simultaneously targeting the RANKL-expressing malignant cells for NK cells ADCC. After the preclinical validation, we envisage our constructs to be produced in an University-owned production unit according to GMP guidelines with the aim to enable rapid clinical testing in cancer patients.

NK细胞在肿瘤的免疫泡沫中起着重要作用，并且由于它们有能力介导抗体依赖性细胞毒性（ADCC）的能力，因此很大程度上有助于鼠李妥昔单抗等治疗性抗体的临床疗效。因此，目前的多种策略旨在增加抗体诱导NK细胞针对肿瘤细胞的潜力。 NK细胞的直接抗肿瘤反应性和ADCC都受到NK细胞表达的受体的各种配体的影响，因此中和抑制性分子的中和化非常有用，可以很好地增加组成型和治疗诱导的NK细胞抗肿瘤免疫。在最后一个资金期间，我们证明了TNFR家族成员等级（主要以其在骨代谢中的作用而闻名），由NK细胞表达，而其对应物RANKL则由恶性造血细胞表达。我们发现RANKL能够将信号转移到表达配体的恶性细胞（反向信号）中，从而导致细胞因子释放，这些细胞因子充当自分泌/旁分泌生长和恶性疾病中的生存因子。此外，在RANKL信号传导上释放的因子损害了NK细胞的抗肿瘤反应性，并在NK细胞上诱导了等级表达，后者进一步被发现将信号传递到NK细胞中，从而损害了其抗肿瘤反应性，从而促进了表达降压细胞的免疫逃生。基于这些发现，我们开发了FC工程的等级融合蛋白，能够中和RankL对抗肿瘤免疫的有害功能，同时靶向恶性细胞，通过靶向恶性细胞来有效刺激NK细胞ADCC。信号。此外，我们的目的是确定降级介导观察到的NK细胞毒性和细胞因子产生的差异抑制的分子机制。基于我们关于人和鼠NK细胞在合成小鼠肿瘤模型中观察到的ADCC诱导的差异敏感性的发现，即将进行的研究的重点是建立合适的人源性小鼠模型，以进一步促进我们的FC工程级别级别融合蛋白。这种模型被希望最终验证了我们的策略，以通过中和RANKL的抑制作用并同时靶向NK细胞ADCC的RANKL表达恶性细胞，从而双重地增强对恶性造血细胞的NK反应性。临床前验证后，我们设想根据GMP指南在大学拥有的生产单元中生产的结构，以便在癌症患者中快速临床测试。