Experimental Uveal Melanoma and Ocular Immune Privilege

葡萄膜黑色素瘤是成人最常见的原发恶性眼内肿瘤。脑转移瘤 肝脏是葡萄膜黑色素瘤患者的主要死亡原因，目前尚无有效的治疗方法 治疗。开发和测试葡萄膜黑色素瘤的治疗方法因缺乏 葡萄膜黑素细胞原位转化并转移到肝脏的满意动物模型。在……里面 此外，很少有眼部来源的小鼠黑色素瘤细胞系可用于旨在了解 葡萄膜黑色素瘤的免疫逃逸和肝转移机制。这项提议的目标是 构建SV40 T抗原(Tag)转基因载体，通过以下途径诱导表达SV40 Tag 酪氨酸酶启动子在Cre-重组酶存在的情况下。这种转基因将允许在原位诱导 C57BI/6小鼠体内包括黑素细胞在内的有色组织通过靶向给药转化为 眼睛的前段或后段可以诱导Cre重组酶的活性。这些老鼠将被用来 通过监测SV40标记来表征对原发和转移性葡萄膜黑色素瘤的免疫反应 特定的免疫反应。对SV40标签的免疫应答在C57BI/6小鼠和 由可溶性MHC Class I：SV40标签多肽组成的四聚体可与SV40标签一起提供 特异性TCR转基因株用于研究CD8+肿瘤特异性T细胞在体内的命运 原发和转移性葡萄膜黑色素瘤。此外，这些SV40标签转基因小鼠将成为 产生葡萄膜黑色素瘤细胞系。由于酪氨酸酶启动子在皮肤黑素细胞中也很活跃， 这种转基因小鼠也可以作为药物诱导的皮肤黑色素瘤模型。 对皮肤的传递。SV40标签诱导葡萄膜黑色素瘤和皮肤黑色素瘤细胞系的比较 转基因小鼠可能发现控制免疫逃避和肝转移相关的新分子 有葡萄膜黑色素瘤，但没有皮肤黑色素瘤。了解葡萄膜免疫逃逸的机制 黑色素瘤可能导致促进肿瘤消除的治疗方法。此外，操纵 这些免疫抑制机制可能被用来抑制T细胞反应以延长移植物 例如，眼内移植，RPE移植，或减轻T细胞介导的自身免疫性葡萄膜炎。

Uveal melanoma is the most common primary malignant intraocular tumor in adults. Metastatic disease of the liver is the leading cause of death in uveal melanoma patients and there is currently no effective treatment. Developing and testing therapies for uveal melanoma has been hampered by the absence of a satisfactory animal model in which uveal melanocytes are transformed in situ and metastasize to the liver. In addition, few murine melanoma cell lines of ocular origin are available for studies aimed at understanding the mechanisms of immune evasion and liver metastasis by uveal melanoma. The objective of this proposal is to develop an SV40 T-antigen (Tag) transgene with elements that allow inducible expression of SV40 Tag by the tyrosinase promoter in the presence of Cre-recombinase. This transgene will permit inducible in situ transformation of pigmented tissues, including melanocytes, in C57BI/6 mice, by targeted drug delivery into the anterior or posterior segments of the eye to induce Cre-recombinase activity. These mice will be used to characterize the immune response to primary and metastatic uveal melanoma by monitoring SV40 Tag- specific immune responses. The immune response to SV40 Tag is well characterized in C57BI/6 mice and tetramers composed of soluble MHC Class I : SV40 Tag peptides are available along with an SV40 Tag specific TCR transgenic strain for studies aimed at determining the fate of CD8+ tumor-specific T cells in primary and metastatic uveal melanoma. In addition, these SV40 Tag transgenic mice will be a source for generating uveal melanoma cell lines. As the tyrosinase promoter is also active in cutaneous melanocytes, this transgenic mouse strain may also serve as a model of cutaneous melanoma which is inducible by drug delivery to the skin. Comparison of uveal and cutaneous melanoma cell lines derived from SV40 Tag transgenic mice may reveal novel molecules that control immune evasion and liver metastasis associated with uveal but not cutaneous melanoma. Understanding the mechanisms of immune evasion by uveal melanomas may lead to therapeutic approaches to promote tumor elimination. Furthermore, manipulation of these immune-suppressive mechanisms may be employed to inhibit T cell responses to prolong graft transplantation in the eye, for example, RPE transplants, or mitigate T cell mediated autoimmune uveitis.