Cutting Edge: NFAT Transcription Factors Promote the Generation of Follicular Helper T Cells in Response to Acute Viral Infection
Follicular CD4+ Th (Tfh) cells provide B cell help in germinal center reactions that support class switching, somatic hypermutation, and the generation of high affinity Abs. In this article, we show that deficiency in NFAT1 and NFAT2 in CD4+ T cells leads to impaired germinal center reactions upon viral infection because of reduced Tfh cell differentiation and defective expression of proteins involved in T/B interactions and B cell help, including ICOS, PD 1, and SLAM family receptors. Genome wide chromatin immunoprecipitation data suggest that NFAT proteins likely directly participate in regulation of genes important for Tfh cell differentiation and function. NFAT proteins are important TCR and Ca2+ dependent regulators of T cell biology, and in this article we demonstrate a major positive role of NFAT family members in Tfh differentiation.
The Journal of Immunology