Basophils express a type 2 cytokine profile on exposure to proteases from helminths and house dust mites

TLDR

Proteolytic activities from allergens and parasite secretions are key immunomodulators that may drive IgE synthesis, eosinophil recruitment, and type 2 T cell development. The study examined whether the protease activity of house dust mite Der p1 and hookworm Necator americanus secreted proteases can directly trigger type 2 cytokine production by basophils. Basophils purified from human peripheral blood were exposed to Der p1 and N. americanus proteases, and cytokine responses were measured to confirm the effect.

Abstract

Abstract The proteolytic activities frequently associated with sources of allergens and parasite secretions have been suggested as important immunomodulators. We have investigated whether the protease activity of the house dust mite allergen Der p1 and the secreted proteases of the hookworm Necator americanus are able to directly induce type 2 cytokine production by basophils. Der p1 and the secretions of N. americanus induced interleukin (IL)-4, IL-5, and IL-13 but not interferon-γ mRNA in KU812 basophils. Enzyme-linked immunosorbent assay confirmed that IL-4 and IL-13 were secreted. A nonproteolytic antigen failed to induce cytokine expression, and preincubation of Der p1 or N. americanus secretions with protease inhibitors inhibited cytokine expression. Data were confirmed using basophils purified from human peripheral blood. We speculate that tis innate mechanism may contribute to the development of a cytokine milieu that could promote immunoglobulin E synthesis, eosinophil recruitment, and the development of type 2 T cells.