The inflammatory airway response in allergic asthma may be the result of immune cells that are dysregulated towards environmental factors such as airborne fungi. The long-term goal of this project is to better understand the pathophysiological mechanisms of Th2-type (allergic) airway inflammation. Exposure to the fungus, Alternaria, has long been implicated in the development and exacerbation of allergic airway disorders such as rhinitis, atopic asthma, and CRS. After intranasal exposure to Alternaria spores, antigens, and fungal cell wall polymers such as chitin, naive mice exhibit marked eosinophilic airway inflammation, enhanced Th2 responses, and airway hyperreactivity. Despite the well-documented clinical importance of Alternaria in the development, onset, and exacerbation of allergic airway diseases, little knowledge exists about the role of individual fungal products/components in theses pathological states. The importance of the fungal cell wall polymer chitin has been explored to some extent in the context of inflammation and has been shown to drive immune responses favoring the development of allergic disease. We have discovered a novel receptor candidate for chitin expressed in lung epithelial cells. In this exploratory project we will further our understanding of how chitin binds to this receptor and begin to elucidate the role of this receptor candidate in the context of innate immunity and allergic inflammatory responses using lung epithelial cells and mouse models. Execution of this project will lead to a better understanding of the mechanisms of persistent and recurrent airway inflammation and may lead to the development of more specific, effective therapies and prevention strategies.

Public Health Relevance

Public Health Statement Westernized countries are experiencing striking increases in the prevalence of asthma. Successful completion of this project will increase our understanding of the pathogenesis mechanisms of the allergic asthma- associated fungus, Alternaria and other chitin containing pathogens. Successful execution of this project may provide insight into the design and implementation of novel therapeutic approaches for prevention and treatment of allergic asthma and other Th2 driven inflammatory diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AI115986-01
Application #
8839039
Study Section
Hypersensitivity, Autoimmune, and Immune-mediated Diseases Study Section (HAI)
Program Officer
Minnicozzi, Michael
Project Start
2015-05-18
Project End
2017-04-30
Budget Start
2015-05-18
Budget End
2016-04-30
Support Year
1
Fiscal Year
2015
Total Cost
Indirect Cost
Name
Virginia Polytechnic Institute and State University
Department
Type
Organized Research Units
DUNS #
003137015
City
Blacksburg
State
VA
Country
United States
Zip Code
24060
Hayes, Tristan; Rumore, Amanda; Howard, Brad et al. (2018) Innate Immunity Induced by the Major Allergen Alt a 1 From the Fungus Alternaria Is Dependent Upon Toll-Like Receptors 2/4 in Human Lung Epithelial Cells. Front Immunol 9:1507
Grover, Shivani; Lawrence, Christopher B (2017) The Alternaria alternata Mycotoxin Alternariol Suppresses Lipopolysaccharide-Induced Inflammation. Int J Mol Sci 18:
Yuan, Ruoxi; Geng, Shuo; Chen, Keqiang et al. (2016) Low-grade inflammatory polarization of monocytes impairs wound healing. J Pathol 238:571-83