Despite interest in T follicular helper (TFH) cell development and function, differences between TFH cells resident in germinal centers (GCs) and phenotypically similar, non-resident TFH cells are unclear. Both TFH subsets share the Bcl6+FoxP3CXCR5hiPD-1hi phenotype but we show that only GC resident TFH cells express S1pr2 and lose CD90 expression. Whereas immunization elicits CD90neg/lo GCTFH and CD90hi GCTFH-like cells similarly, these TFH subsets have distinct properties. CD90neg/lo GCTFH cells require MHCII+ B cells to develop and once formed, do not proliferate. CD90hi GCTFH-like cells are generated in the absence of B cells and remain mitotically active. The Tcr repertoires of both TFH types are initially shared but with time, Tcr usage in CD90hi GCTFH-like cells substantially diverges by DC-driven proliferation. Transcriptome analysis shows CD90neg/lo GCTFH to be specialized for vesicle transport and exocytosis while gene expression in CD90hi GCTFH-like cells is linked to cell activation, proliferation and migration. SOURCE: Garnett,H,Kelsoe Duke University

Pluto Bioinformatics

GSE147035: Characterization of True Germinal center follicular helper T cells