Melanoma-associated chondroitin sulfate proteoglycan (MCSP) as target antigen for specific immunotherapy; from the bench to the bed-side.

针对黑色素瘤相关的硫酸软骨素蛋白多糖(MCSP)进行特异性免疫治疗；从长凳到床边，MCSP是一种很有前途的黑色素瘤和肿瘤间质相关表面抗原。在之前的资助期间，我们参与了MCSP特异性T细胞反应的诱导，并建立了针对电子预测的HLA-A*02限制性表位的T细胞。这些T细胞不能识别内源性MCSP，多肽放散方法显示MCSP显然没有被处理和正常呈现。因此，我们寻求使用MCSP特异性嵌合抗原受体(CARS)来靶向这种抗原，因为它们以一种不依赖于人类白细胞抗原的方式识别MCSP。此外，还建立了MCSP作为肿瘤特异性T细胞的巨噬细胞获得性标志，并对T细胞刺激因子SLAMF6进行了鉴定。巴勒斯坦合作伙伴建立了细胞体外和体外工作所需的基础设施。在目前的应用中，我们希望通过进行I期临床试验来将这种方法应用于临床，在I期临床试验中，我们打算用自体T细胞治疗皮肤黑色素瘤和葡萄膜黑色素瘤患者，自体T细胞与编码MCSP特异性CAR的mRNA电穿孔。10名患者应纳入主要终点的安全性和可行性。临床疗效将被视为次要终点。以色列的合作伙伴将继续他们对SLAMF6的研究，以确定它是否可以用于扩大更好的T细胞以进行过继转移，并将首先用这些T细胞在小鼠身上进行体内实验，这些T细胞转染有MCSP特异性CAR。巴勒斯坦小组将检查非皮肤黑色素瘤的突变和抗原表达，非皮肤黑色素瘤在巴勒斯坦人口中占很大比例。在将在巴勒斯坦逗留一段时间的Erlangen荧光显微镜专家的帮助下，巴勒斯坦首席研究员、癌症病理学家将对来自巴勒斯坦、以色列和德国的肿瘤样本进行免疫病理研究，包括试验患者以及以色列CAR治疗组小鼠的肿瘤样本，以确定炎症环境、T细胞和其他免疫细胞的渗透以及MCSP的表达。

Targeting Melanoma-associated chondroitin sulfate proteoglycan (MCSP) for specific immunotherapy; from bench to bedside MCSP is a promising melanoma- and tumor-stroma-associated surface antigen. Within the previous funding period, we engaged in the induction of MCSP-specific T-cell responses, and established T cells specific for in silico-predicted HLA-A*02-restricted epitopes. These T cells failed to recognize endogenous MCSP and a peptide elution approach revealed that MCSP is apparently not processed and presented normally. Therefore we pursued the use of MCSP-specific Chimeric Antigen Receptors (CARs) to target this antigen, because they recognize MCSP in an HLA-independent fashion. In addition, MCSP was established as trogocytosis-acquired marker of tumor-specific T cells and the T-cell-stimulatory factor SLAMF6 was characterized. The Palestinian partner established the infrastructure required for cellular ex vivo and in vitro work. In the current application, we wish to take this approach to the clinic by performing a phase I clinical trial in which we intend to treat cutaneous melanoma and uveal melanoma patients with autologous T cells, which are electroporated with mRNA encoding an MCSP-specific CAR. Ten patients shall be included with the primary end-points safety and feasibility. Clinical efficacy will be addressed as secondary end-point. The Israeli partner will continue their investigation on SLAMF6 to determine whether it can be used to expand better T cells for adoptive transfer and will perform first in vivo experiments with these T cells, transfected with the MCSP-specific CAR in mice. The Palestinian group will examine the mutations and antigen-expression of non-cutaneous melanomas, which represent a large part of melanomas in the Palestinian population. With the help of a specialist for fluorescence microscopy from Erlangen, who will spend some time in Palestine, the Palestinian principal investigator, who is a cancer pathologist, will perform immunopathological investigations of tumor samples from Palestine, Israel, and Germany, including the trial patients, as well as from the CAR-treated mice of the Israeli group, to determine the inflammatory milieu, infiltration of T cells and other immune cells, and the MCSP-expression.