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Germinal centers continually recruit naïve T cells that alter the balance between follicular T helper and follicular regulatory T cells.

ABSTRACT: Follicular helper T cells (T FH ) mediate B cell selection and clonal expansion in germinal centers (GCs), and follicular regulatory T cells (T FR ) prevent the emergence of self-reactive B cells and help to extinguish the reaction. Here we show that GC reactions continually recruit T cells from both the naïve conventional and naive thymic regulatory T cell (Treg) repertoires. In the early GC, newly recruited T cells develop into T FH , whereas cells entering during the contraction phase develop into T FR cells that contribute to GC dissolution. The T FR fate decision is associated with decreased antigen availability and is modulated by slow antigen delivery or mRNA vaccination. Thus, invasion of ongoing GCs by newly developing T FH and T FR from naïve conventional and Treg repertoires, helps remodel the GC based on antigen availability.

ORGANISM(S): Mus musculus

PROVIDER: GSE240730 | GEO | 2023/08/19

REPOSITORIES: GEO

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