T-cell receptor based therapeutics for cytomegalovirus

描述(由研究人员提供)：这些研究的目标是评估使用基于T细胞受体的融合蛋白作为治疗CMV的靶向试剂的可行性，CMV仍然是免疫功能低下患者发病率和死亡率的主要原因。在这些研究中，克隆了一个TCR，它识别细胞表面存在的人类巨细胞病毒被膜蛋白pp65中的一个独特的、自然加工的、高免疫原性的多肽片段。该TCR是从巨细胞病毒多肽刺激人类白细胞抗原A2阳性的人PBMC产生的CD8+T细胞中分离出来的。制备了CMV特异性单链TCR/IgG1融合蛋白CMVscTCR/IgG1，并在哺乳动物细胞中高效表达和纯化鉴定。该融合蛋白将在体外鉴定MHC限制性多肽的特异性结合、稳定性、亲和力、靶向抗原阳性细胞的能力以及结合靶细胞和效应细胞的能力。最后，CMVscTCR/IgG1融合蛋白将在体内进行药代动力学和毒性评估。这些研究的成功完成将导致在一种新的人CMV感染小鼠模型中进行体内疗效研究，并最终生产出用于商业化的基于TCR的靶向CMV疗法。

DESCRIPTION (provided by investigator): The goal of these studies is to evaluate the feasibility of using a T-cell receptor based fusion protein as a targeting agent for therapies for CMV, which remains a major cause of morbidity and mortality inimmunocompromised patients. For these studies a TCR recognizing a distinct, naturally processed, highly immunogenic peptide fragment from the human cytomegalovirus tegument protein pp65 presented on the cell surface in the context of HLA-A2 was cloned. This TCR was isolated from CMV peptide specific CD8+ T-cells that were generated by CMV peptide stimulation of HLA-A2 positive human PBMC. A CMV specific single chain TCR/IgG1 fusion protein, CMVscTCR/IgG1, was prepared and will be expressed at high levels in mammalian cells and purified for characterization. The fusion protein will be characterized in vitro for MHC restricted peptide specific binding, stability, affinity, ability to target antigen positive cells, and ability to conjugate target and effector cells. Finally, the CMVscTCR/IgG1 fusion protein will be evaluated in vivo for pharmacokinetics and toxicity. Successful completion of these studies will lead to in vivo efficacy studies in a novel mouse model of human CMV infection and to eventual production of TCR-based targeted CMV therapeutics for commercialization.