Role of chitinases in development of allergic asthma.

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K08395
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54020:Connective tissue disease and allergy-related
• Research Institution: Kyorin University
• Principal Investigator: Arae Ken 杏林大学, 保健学部, 准教授 (50306669)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: キチン / アレルギー

Outline of Final Research Achievements

Exposure to various antigens derived from house dust mites (HDM) is considered to be a risk factor for development of certain allergic diseases such as atopic asthma. Chitin is an insoluble polysaccharide and a major component in the outer shell of HDMs. Mice exposed to chitin develop asthma-like airway eosinophilia. In the present study, we show that chitin induced production of IL-33 and TSLP by alveolar and bronchial epithelial cells, respectively, in mice. IL-25, IL-33 and TSLP were reported to be important for group 2 innate lymphoid cell (ILC2)-, but not Th2 cell-, dependent airway eosinophilia in a certain model using chitin beads. Here, we show that epithelial cell-derived IL-33 and TSLP, but not IL-25, were crucial for activation of resident lung Th2 cells as well as ILC2s to produce IL-5, resulting in development of chitin-induced airway eosinophilia.

Free Research Field

免疫学、アレルギー

Academic Significance and Societal Importance of the Research Achievements

キチンは、寄生虫のほか、エビ・カニなどの甲殻類、ハチ・ゴキブリなどの昆虫類、カビなどの真菌類に共通する外殻構成成分となっている。興味深いことに、これらの生物はヒトにとってアレルギー応答・2型免疫応答（Th2細胞、好酸球およびIgE産生を中心とする免疫応答）を引き起こす生物群である。したがって、キチンによる炎症誘発機構を解明できれば、アレルギー疾患のみならず、寄生虫の感染防御機構の解明に大きな貢献をもたらす可能性も期待される。