Identification of a T follicular helper cell subset that drives anaphylactic IgE

Thirteen is the charm in anaphylaxis Immunoglobulin E (IgE) is a type of antibody associated with allergies and response to parasites such as worms. When high-affinity, allergen-specific IgE binds its target, it can cross-link receptors on mast cells that induce anaphylaxis. It remains unclear, however, how B cells are instructed to generate high-affinity IgE. Gowthaman et al. discovered a subset of T follicular helper cells (T FH 13) that direct B cells to do just that. T FH 13 cells are induced by allergens but not during parasite infection. Transgenic mice lacking these cells show impaired production of high-affinity, anaphylactic IgE. T FH 13 cells, which are elevated in patients with food and aeroallergies, may be targeted in future antianaphylaxis therapies. Science , this issue p. eaaw6433