Characterization of the polyclonal TCR repertoire in TCR-beta transgenic mice

描述（由申请人提供）：T细胞受体（TCR）序列的随机生成确保了TCR库能够识别多种病原体。然而，这种巨大的多样性阻碍了对TCR曲目的研究。为了克服这个问题，我们使用了一个固定的TCR- β链模型来促进多克隆TCR库的实验研究。这种TCR库在正常的胸腺和外周环境中发育，并受自然T细胞选择力的影响，包括与皮肤和肠道上共生菌群的自身抗原和外来抗原的潜在相互作用。在先前的研究中，这种固定的TCR- β链模型在表征正常自然产生的TCR库并将其与自身免疫库进行比较方面很有用。我们在此提出，在固定TCR- β链模型中对TCR库的详细了解将有助于研究T细胞生物学的许多方面，因此，该项目的目标是通过基于空间和表型变量从分离的T细胞中对可变TCR- α链进行广泛测序，在个体TCR水平上对这种多克隆TCR库进行完整的原位表征。一个特别的重点领域将是了解自然产生的记忆CD4+ T细胞的TCR特异性，这可能是由于遇到自身或共生抗原而产生的，并且可能具有潜在的致病性。我们相信这些数据将成为未来研究自我反应性调节性和非调节性T细胞、自身免疫性疾病遗传模型、记忆性T细胞以及T细胞运输和体内平衡的基础。

DESCRIPTION (provided by applicant): The random generation of T cell receptor (TCR) sequences ensures a TCR repertoire capable of recognizing a wide variety of pathogens. However, study of the TCR repertoire is hampered by this great diversity. To overcome this issue, we have used a fixed TCR-beta chain model to facilitate experimental study of a polyclonal TCR repertoire. This TCR repertoire develops in a normal thymic and peripheral environment, and is subject to natural T cell selective forces, including potential interactions with self-antigens and foreign antigens from commensal flora on the skin and intestines. In previous studies, this fixed TCR-beta chain model has been useful in characterizing normal naturally arising TCR repertoires and comparing them with autoimmune repertoires. We propose here that detailed knowledge of the TCR repertoire in a fixed TCR- beta chain model will be useful for study of numerous aspects of T cell biology, Thus, the goal of this project is the complete in situ characterization of this polyclonal TCR repertoire at the individual TCR level by extensive sequencing of the variable TCR-alpha chains from T cells isolated based on spatial and phenotypic variables. One particular area of focus will be to understand the TCR specificity of naturally arising memory CD4+ T cells, which presumably arose due to encounter with self or commensal antigens, and may potentially be pathogenic. We believe these data will serve as the foundation of future studies on self-reactive regulatory and non-regulatory T cells, genetic models of autoimmune disease, memory T cells, and T cell trafficking and homeostasis.