Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601, Australia; email:
Lymphocyte Signalling and Development Institute Strategic Programme, Babraham Institute, Cambridge CB22 3AT, United Kingdom; email:
Annu Rev Immunol. 2016 May 20;34:335-68. doi: 10.1146/annurev-immunol-041015-055605. Epub 2016 Feb 22.
Although T cell help for B cells was described several decades ago, it was the identification of CXCR5 expression by B follicular helper T (Tfh) cells and the subsequent discovery of their dependence on BCL6 that led to the recognition of Tfh cells as an independent helper subset and accelerated the pace of discovery. More than 20 transcription factors, together with RNA-binding proteins and microRNAs, control the expression of chemotactic receptors and molecules important for the function and homeostasis of Tfh cells. Tfh cells prime B cells to initiate extrafollicular and germinal center antibody responses and are crucial for affinity maturation and maintenance of humoral memory. In addition to the roles that Tfh cells have in antimicrobial defense, in cancer, and as HIV reservoirs, regulation of these cells is critical to prevent autoimmunity. The realization that follicular T cells are heterogeneous, comprising helper and regulatory subsets, has raised questions regarding a possible division of labor in germinal center B cell selection and elimination.
虽然 T 细胞对 B 细胞的辅助作用在几十年前就已经被描述过，但正是滤泡辅助 T（Tfh）细胞中 CXCR5 的表达的鉴定，以及随后发现它们对 BCL6 的依赖性，使得人们认识到 Tfh 细胞是一个独立的辅助亚群，并加速了发现的步伐。超过 20 种转录因子，连同 RNA 结合蛋白和 microRNAs，控制着趋化受体和 Tfh 细胞功能和稳态重要分子的表达。Tfh 细胞启动 B 细胞启动滤泡外和生发中心抗体反应，对于亲和力成熟和维持体液记忆至关重要。除了 Tfh 细胞在抗菌防御、癌症和 HIV 储库中的作用外，这些细胞的调节对于防止自身免疫至关重要。滤泡 T 细胞是异质性的，包括辅助和调节亚群，这一认识引发了关于生发中心 B 细胞选择和消除中可能存在分工的问题。
