Table of Contents
Journal of Allergy
Volume 2012, Article ID 903659, 11 pages
Review Article

Role of Allergen Source-Derived Proteases in Sensitization via Airway Epithelial Cells

Department of Internal Medicine, Akishima Hospital, 1260 Nakagami-Cho, Akishima-Shi, Tokyo 196-0022, Japan

Received 14 July 2011; Revised 14 September 2011; Accepted 4 October 2011

Academic Editor: Peter Borger

Copyright © 2012 Yasuhiro Matsumura. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Protease activity is a characteristic common to many allergens. Allergen source-derived proteases interact with lung epithelial cells, which are now thought to play vital roles in both innate and adaptive immune responses. Allergen source-derived proteases act on airway epithelial cells to induce disruption of the tight junctions between epithelial cells, activation of protease-activated receptor-2, and the production of thymic stromal lymphopoietin. These facilitate allergen delivery across epithelial layers and enhance allergenicity or directly activate the immune system through a nonallergic mechanism. Furthermore, they cleave regulatory cell surface molecules involved in allergic reactions. Thus, allergen source-derived proteases are a potentially critical factor in the development of allergic sensitization and appear to be strongly associated with heightened allergenicity.