MANIPULATION OF CD40 CD40L IN CTL BASED IMMUNOTHERAPY

描述：(申请者摘要)成功申请癌症 免疫治疗需要对CD8+细胞毒T细胞有更深入的了解 调节淋巴细胞(CTL)以有效控制肿瘤生长 限制自身免疫损伤。CTL激活途径的最新研究进展 耐受性表明，内源性或转基因的CTL群体可以 在体内控制抗原提呈细胞(APC)功能水平 通过操纵CD40-CD40L相互作用。对此，显然有 需要生理上相关的自发性癌症动物模型 将允许研究这些肿瘤-免疫系统的相互作用，并允许 对以APC为重点的免疫治疗策略的有用评估。这样做的目的是 研究就是开发这样一个功能强大的新型模型系统，其中的能力 APC对肿瘤特异性CD8+细胞毒和CD4+辅助T细胞的调节作用 可以在原发内源性肿瘤的发展过程中评估反应 表达一种模型自身抗原。这个肿瘤模型的一部分涉及转基因 大鼠控制下高效表达SV40T抗原癌基因的小鼠 胰岛素启动子(RIP-Tag2)。RIP-Tag2小鼠患上胰腺β细胞瘤 导致胰岛素自主分泌和3-4分钟内发生致命低血糖 月份。RIP-Tag2小鼠将与表达卵白蛋白的RIP-Mova小鼠杂交 (OVA)作为胰腺和近端小管上皮细胞的自身抗原 肾脏的细胞。在RIP-Mova小鼠中，OVA有效地交叉呈现在 宿主APC，导致OVA特异性CTL的删除，该CTL可被 CD4+OVA特异性辅助性T细胞。转基因OVA特异性CTL(OT-I细胞)将 在不同时间过继转移到RIP(Tag2 X Mova)小鼠体内 表达OVA的β细胞肿瘤的发生发展。CTL的能力 控制肿瘤生长与导致自身免疫损伤的对比将由I进行检查) 监测血糖水平(反映肿瘤负担和自身免疫 破坏正常的β细胞)，ii)胰腺的组织学检查和 肾脏，III)转移的CTL的持久性和激活/耐受性 (体外测量)，以及iv)对生存的影响。以APC为重点的监管 OT-I细胞将尝试使用OVA特异性的CD4+T细胞或刺激性 抗CD40抗体对OT-I细胞的诱导和维持及抑制作用 抗CD40L抗体调节OT-I细胞的反应。希望是这样的 这个项目将产生一种更好的动物模型来探索 影响肿瘤控制与自身免疫平衡的因素 基于CTL的免疫治疗。

DESCRIPTION: (Applicant's Abstract) The successful application of cancer immunotherapy will require a deeper understanding of CD8+ cytotoxic T lymphocyte (CTL) regulation in order to effectively control tumor growth while limiting autoimmune damage. Recent insights into the pathways of CTL activation and tolerance suggests that endogenous or transfected CTL populations can be controlled in vivo at the level of antigen-presenting cell (APC) function through manipulation of CD40-CD40L interactions. Towards this, there is clearly a need for physiologically relevant animal models of spontaneous cancer that will allow the study of these tumor-immune system interactions and permit a useful evaluation of APC-focused immunotherapeutic strategies. The goal of this research is to develop such a powerful new model system in which the capacity of APC to regulate tumor-specific CD8+ cytotoxic and CD4+ helper T cell responses can be assessed during the development of a primary endogenous tumor expressing a model self-antigen. Part of this tumor model involves transgenic mice expressing the potent SV40 T antigen oncogene under the control of the rat insulin promoter (RIP-Tag2). RIP-Tag2 mice develop pancreatic beta-cell tumors leading to autonomous insulin secretion and lethal hypoglycemia within 3-4 months. RIP-Tag2 mice will be crossed with RIP-mOVA mice that express ovalbumin (OVA) as a self-antigen in beta cells of the pancreas and proximal tubular cells of the kidney. In RIP-mOVA mice, OVA is efficiently cross-presented on host APC, leading to the deletion of OVA-specific CTL which can be blocked by CD4+ OVA-specific helper T cells. Transgenic OVA-specific CTL (OT-I cells) will be adoptively transferred to the RIP(Tag2 x mOVA) mice at various times during the development of OVA-expressing beta cell tumors. The ability of the CTL to control tumor growth versus causing autoimmune damage will be examined by i) monitoring of blood glucose levels (reflecting tumor burden and autoimmune destruction of normal beta cells), ii) histological examination of pancreas and kidneys, iii) the persistence, and activation/tolerization of transferred CTL (measured in vitro), and iv) effect on survival. APC-focused regulation of the OT-I cells will be attempted using OVA-specific CD4+ T cells or stimulatory anti-CD40 antibodies to induce and maintain OT-I cells and inhibitory anti-CD40L antibodies to tune down the responses of OT-I cells. It is hoped that this project will result in a superior animal model in which to explore factors that influence the balance between tumor control and autoimmunity in CTL-based immunotherapy.