Tfh Summary

发表于 2023-05-22 分类于 paper ， review ， celltype 阅读次数：本文字数： 998 阅读时长 ≈ 4 分钟

Tfh总结1

Title: T Follicular Helper Cells

Journal: Encyclopedia of Cell Biology (Second Edition)

Authors: Filipa Ribeiro; Michelle Linterman; Luis Graca

Pub.date: 2023

DOI: 10.1016/B978-0-12-821618-7.00137-1

Tfh的功能

“These T-B interactions are critical for the isotype switching and affinity maturation of B cells leading to the production of high-affinity antibodies.”
Bcell成熟的重要性，需要调控，防止产生自身免疫性的B细胞

“The formation of germinal centers (GCs) within secondary lymphoid organs, in response to infection or immunization, is a crucial event for the production of T cell-dependent protective antibodies. Within GCs, mature B cells undergo affinity maturation and somatic hypermutation (SHM), leading to the production of antibodies that bind pathogens with high affinity. These antibodies can neutralize infectious agents providing protection against subsequent infection, leading to effective humoral responses and memory. Nevertheless, the unpredictability of the SHM can result in the generation of autoreactive B cell clones, thus contributing to a dysregulated humoral response that can lead to autoimmune diseases (Vinuesa et al., 2009). Consequently, the GC reaction requires strict regulation to ensure a balanced humoral immune response by guaranteeing the emergence of high-affinity B cell clones targeting pathogens while preventing the generation of autoreactive GC B cells.”

Tfh的关键作用

“Tfh cells provide crucial signals to B cells to support GC development and function by mediating affinity maturation through the positive selection of GC B cells”
关键基因：BCL6、CXCR5、ICOS、PD-1、SLAM、SAP、PRDM1
CD4 Tfh Marker
Tfh细胞分化
- DC刺激CD4 NaiveT
  - MHC II呈递抗原
  - CD80/86-CD28提供共刺激信号
  - ICOS-ICOSL提供定位信号，将TFH定位于TB边界
- pre-Tfh与B细胞相互作用：获得迁移到 GC 并完成其发育为 GC Tfh 细胞的能力
  - TCR-MHC II
  - CD28-CD80/86
  - ICOS-ICOSL
  - CD40L-CD40
  - SAP-SFR
- Tfh与B细胞的相互作用：Tfh 细胞产生 IL-4 和 IL-21，从而为 B 细胞提供支持
  - TCR-MHC II
  - CD28-CD80/86
  - ICOS-ICOSL
  - CD40L-CD40
  - SAP-SFR
  - PD-1-PD-L1