Human gamma-delta (γδ) T cells specific for common allergens are Th1-polarized in allergic donors. Yu et al.
Description
Gamma-delta (γδ) T cells are a bridge between innate and adaptive immunity and are involved in various immunological disorders. Here we identify and present an initial characterization of human allergen-reactive γδ T cells in peripheral blood, using an activation-induced marker assay targeting upregulated 4-1BB and CD69 expression. Broad and reproducible ex vivo allergen-reactive γδ T cell responses were detected in donors sensitized to mouse, cockroach, house dust mite, and timothy grass, as well as in non-allergic participants. The reactivity to 4 different allergen extracts was readily detected in 54.2-100% of allergic subjects (0.02-16.91% of total γδ T cell response) in a donor- and allergen-specific pattern, and abrogated by TCR-blocking. Analysis of CD40L upregulation and intracellular cytokine staining revealed a Th1-polarized response against mouse and cockroach extract stimulation. These results support the existence of allergen-reactive γδ T cells and their possible use to rebalance dysregulated Th2 responses in allergic diseases.