Department of Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid, Box 8118, St. Louis, MO, 63110, USA.
Curr Top Microbiol Immunol. 2014;373:49-67. doi: 10.1007/82_2013_319.
The vertebrate antigen receptors are anticipatory in their antigen recognition and display a vast diversity. Antigen receptors are assembled through V(D)J recombination, in which one of each Variable, (Diverse), and Joining gene segment are randomly utilized and recombined. Both gene rearrangement and mutational insertion are generated through randomness; therefore, the process of antigen receptors generation requires a rigorous testing system to select every receptor which is useful to recognize foreign antigens, but which would cause no harm to self cells. In the case of T cell receptors (TCR), such a quality control responsibility rests in thymic positive and negative selection. In this review, we focus on the critical involvement of self-peptides in the generation of a T cell repertoire, discuss the role of T cell thymic development in shaping the specificity of TCR repertoire, and directing function fitness of mature T cells in periphery. Here, we consider thymic positive selection to be not merely a one-time maturing experience for an individual T cell, but a life-long imprinting which influences the function of each individual T cell in periphery.
脊椎动物抗原受体在抗原识别方面具有前瞻性，表现出极大的多样性。抗原受体通过 V(D)J 重组进行组装，其中每个可变（Diverse）和连接基因片段都随机利用和重组。基因重排和突变插入都是通过随机性产生的；因此，抗原受体产生的过程需要一个严格的测试系统来选择每个受体，这些受体有助于识别外来抗原，但不会对自身细胞造成伤害。在 T 细胞受体（TCR）的情况下，这种质量控制责任在于胸腺的阳性和阴性选择。在这篇综述中，我们重点关注自身肽在 T 细胞库产生中的关键作用，讨论 T 细胞胸腺发育在塑造 TCR 库特异性和指导成熟 T 细胞在外周功能适应性方面的作用。在这里，我们认为胸腺阳性选择不仅仅是个体 T 细胞的一次性成熟体验，而是一种终身印记，影响外周每个个体 T 细胞的功能。
