Human Foxp3-negative follicular regulatory T cells control IgE responses

Antibody responses to most infectious and food protein antigens depend on help to B cells from specialised T follicular helper (Tfh) cells. A subset of Foxp3+ regulatory T cells (Tregs) has been described in mice, with a prominent role in repressing germinal center reactions that are critical for memory B cell formation and long-lived antibody responses. These specialised Tregs co-opt the Bcl-6-dependent Tfh differentiation pathway in order to access the B cell-rich follicles and have therefore been designated as T follicular regulatory (Tfr) cells.