[HTML][HTML] Airway epithelium–shifted mast cell infiltration regulates asthmatic inflammation via IL-33 signaling

MC Altman, Y Lai, JD Nolin, S Long… - The Journal of …, 2020 - Am Soc Clin Investig
MC Altman, Y Lai, JD Nolin, S Long, CC Chen, AM Piliponsky, WA Altemeier, M Larmore…
The Journal of Clinical Investigation, 2020Am Soc Clin Investig
Asthma is a heterogeneous syndrome that has been subdivided into physiologic
phenotypes and molecular endotypes. The most specific phenotypic manifestation of asthma
is indirect airway hyperresponsiveness (AHR), and a prominent molecular endotype is the
presence of type 2 inflammation. The underlying basis for type 2 inflammation and its
relationship to AHR are incompletely understood. We assessed the expression of type 2
cytokines in the airways of subjects with and without asthma who were extensively …
Asthma is a heterogeneous syndrome that has been subdivided into physiologic phenotypes and molecular endotypes. The most specific phenotypic manifestation of asthma is indirect airway hyperresponsiveness (AHR), and a prominent molecular endotype is the presence of type 2 inflammation. The underlying basis for type 2 inflammation and its relationship to AHR are incompletely understood. We assessed the expression of type 2 cytokines in the airways of subjects with and without asthma who were extensively characterized for AHR. Using quantitative morphometry of the airway wall, we identified a shift in mast cells from the submucosa to the airway epithelium specifically associated with both type 2 inflammation and indirect AHR. Using ex vivo modeling of primary airway epithelial cells in organotypic coculture with mast cells, we show that epithelial-derived IL-33 uniquely induced type 2 cytokines in mast cells, which regulated the expression of epithelial IL33 in a feed-forward loop. This feed-forward loop was accentuated in epithelial cells derived from subjects with asthma. These results demonstrate that type 2 inflammation and indirect AHR in asthma are related to a shift in mast cell infiltration to the airway epithelium, and that mast cells cooperate with epithelial cells through IL-33 signaling to regulate type 2 inflammation.
The Journal of Clinical Investigation