TCR Gene Transfer for Treating HCV-Associated Malignancies

描述(申请人提供)：丙型肝炎病毒(丙型肝炎病毒)感染约3%的世界人口，经常导致相关疾病，包括肝硬变和肝细胞癌(肝癌)。由于有效疗法有限，疫苗开发缓慢，治疗和预防感染及其相关疾病的替代方法势在必行。一种基于免疫的靶向治疗方法利用过继T细胞转移来基因工程个人的T细胞，使其对所选择的抗原产生反应。我们的实验室之前已经证明了它能够成功地用逆转录病毒载体重定向外周血淋巴细胞(PBL)来源的T细胞，以便识别靶抗原。重新引导T细胞识别黑色素瘤相关抗原的研究已经导致正在进行的治疗转移性疾病的I/II期临床试验。我们相信这种方法可以应用于丙型肝炎病毒感染和丙型肝炎病毒相关的恶性肿瘤。本实验室已从人类PBL来源的T细胞克隆中克隆并表达了两个具有识别丙型肝炎病毒多肽NS3：1406-1415和NS3：1073-1081的功能TCR。此外，我们还证明了这些TCR是高亲和力的TCR，因为它们具有CD8独立的靶细胞识别能力，并且可以识别自然发生的突变逃逸变体。我们认为，将T细胞重定向以识别诱变的丙型肝炎病毒抗原的方法可能对了解TCR生物学以及产生治疗丙型肝炎病毒感染和相关疾病的临床疗法有好处。基于这些观察，我们假设TCR具有广泛反应性的能力并不是这些分离克隆所独有的，在已解决的丙型肝炎病毒感染患者中，可能存在多种TCR，具有识别病毒蛋白的许多表位的能力。我们还推测，转导丙型肝炎病毒TCR的T细胞在体外具有识别和杀伤表达野生型和突变型丙型肝炎病毒抗原的肿瘤细胞的能力，并在体内能够介导丙型肝炎病毒阳性肿瘤细胞的消退。已经制定了三个具体目标来检验这些假说。目的1验证我们的假设，即来自丙型肝炎病毒感染者的丙型肝炎病毒反应性T细胞而不是丙型肝炎病毒慢性感染者的丙型肝炎病毒反应性T细胞表达识别野生型和广谱变异的丙型肝炎病毒抗原的TCR。目的2将验证一种假设，即来自丙型肝炎病毒感染者的丙型肝炎病毒反应性T细胞的TCR可以将这种针对变异的丙型肝炎病毒抗原的反应性转移到其他T细胞。目的3验证丙型肝炎病毒TCR转导的T细胞可在小鼠体内移植瘤模型中介导表达野生型和突变型丙型肝炎病毒抗原的肝癌的消退。总体而言，这项建议将产生新的信息，可能导致更好地了解TCRs识别多个突变的丙型肝炎病毒表位的能力，并将有助于开发治疗丙型肝炎相关肝细胞癌患者的新疗法。

DESCRIPTION (provided by applicant): Hepatitis C virus (HCV) infects approximately 3% of the world's population, often causing associated diseases including cirrhosis of the liver and hepatocellular carcinoma (HCC). With limited effective therapies and slow vaccine development, alternative approaches for treatment and prevention of infection and its associated diseases is imperative. An immune-based approach for targeted therapy utilizes adoptive T cell transfer to genetically engineer an individual's T cells to become reactive to an antigen of choice. Our lab has previously demonstrated its ability to successfully redirect peripheral blood lymphocyte (PBL)-derived T cells with retroviral vectors in order to recognize target antigens. Studies redirecting T cells to recognize melanoma- associated antigens have led to ongoing Phase I/II clinical trials for treating metastatic disease. We believe this approach can be applied to HCV infections and HCV-associated malignancies. Our lab has cloned and expressed two functional TCRs from PBL-derived T cell clones from humans capable of recognizing HCV peptides NS3:1406-1415 and NS3:1073-1081. Additionally, we have shown that these are high affinity TCRs since they have CD8-independent target cell recognition and can recognize naturally occurring mutant escape variants. We believe the approach to redirect T cells to recognize mutagenic HCV antigens may have benefits in understanding TCR biology as well as producing a clinical therapy for HCV infection and associated diseases. Based on these observations, we hypothesize that the ability of a TCR to have broad reactivity is not unique to such isolated clones and that in patients with resolved HCV infection there may exist a variety of TCRs with the capability of recognizing many epitopes of viral proteins. We also hypothesize that HCV TCR transduced T cells have the ability to recognize and kill tumor cells expressing wild type and mutant HCV antigens in vitro and can mediate regression of HCV+ tumor cells in vivo. Three specific aims have been developed to examine these hypotheses. Aim 1 will test our hypothesis that HCV reactive T cells from patients who resolved their HCV infections but not patients with HCV chronic infections express TCRs that recognize wild type and a broad spectrum of mutant HCV antigens. Aim 2 will test the hypothesis that the TCRs from HCV reactive T cells from patients who resolved their HCV infections can transfer this reactivity against mutant HCV antigens to other T cells. Aim 3 will test the hypothesis that HCV TCR transduced T cells can mediate regression of HCC tumors expressing wild type and mutant HCV antigens in mouse xenograft tumor models in vivo. Overall, this proposal will yield novel information that may lead to a better understanding of the capability of TCRs to recognize multiple mutant HCV epitopes and will aid in the development of novel therapeutics for patients with HCV-associated HCC.