Pinning allergies on pathogenic TH2 cells.

David J Cousins

doi:10.1126/scitranslmed.aao0392

Abstract

A new proinflammatory subtype of antigen-specific TH2 cell that expresses CD161 emerges as the pathogenic cell type in allergic disease and is deleted during allergen-specific immunotherapy (Wambre et al, this issue).

Highlights

Th2 cells in allergic disease A number of elegant studies in both mouse and human have shown that the pathology of allergic disease is driven by the type 2 cytokines, which induce different hallmarks of allergic disease: IL-4 induces B-cell isotype switching to produce IgE, IL-5 promotes eosinophil differentiation, migration and survival, and IL-13 induces mucus hypersecretion and fibrosis
Type 2 cytokines can be produced by a variety of innate immune cell types including mast cells, basophils and the more recently identified group 2 innate lymphoid cells (ILC2s)
The expression of the C-type lectin receptor CD161 is closely associated with inflammatory Th17 cells, the authors convincingly demonstrate that these CD27-CD45RB-CRTh2+CD161+ Th2 cells do not express hallmarks of Th17 differentiation including IL-17 and RORgt, distinguishing these cells from those observed by Cosmi et al[4]

Summary

Introduction

Th2 cells in allergic disease A number of elegant studies in both mouse and human have shown that the pathology of allergic disease is driven by the type 2 cytokines, which induce different hallmarks of allergic disease: IL-4 induces B-cell isotype switching to produce IgE, IL-5 promotes eosinophil differentiation, migration and survival, and IL-13 induces mucus hypersecretion and fibrosis. Antigen-specific expression of Type 2 cytokines in response to allergen is restricted to the Th2 subset of T-helper cells.

Results

Conclusion