Innate Immune Responses in the Alternaria-Dendritic Cell Interaction

Exposure to spores and hyphae of Alternaria alternata, an airborne ubiquitous fungus, is clinically associated with allergic airway disorders including allergic rhinitis, asthma, and chronic rhinosinusitis. Dendritic cells are known as the type of antigen presenting cells most often associated with allergic inflammation. In this study, we used mouse bone marrow-derived dendritic cells (BMDCs) as a model to study the ability of A. alternata spores and different components of the spore cell wall to stimulate innate immune responses. We found that BMDCs were highly sensitive to A. alternata spores, chitin and the major allergen Alt a 1. Following stimulation with these molecules, the expression of MHC II and other co-stimulators, like CD40, CD86, and OX40L, were highly up regulated. In order to determine how different cell wall components affect the T cells, we conducted co-culture experiments of BMDCs and lymphocytes in this study. Both spores and Alt a1 did not induce IL-4 in mixed lymphocytes reactions. Interestingly, we found that Alt a 1 induced the switching of the CD4+ T cell population to the Th17 type, with a major increase in IL-17A secretion. This study reveals that A. alternata components may balance the innate immune responses between Th2 and Th17 pathways, and/or contributes to the development and exacerbation of more serve neutrophilic forms of asthma.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Biological Sciences

Department dc:contributor.department

Biological Sciences

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2018

Author dc:creator

• Luo, Mengyao

Chair dc:contributor.committeechair

• Lawrence, Christopher B.

Committee members dc:contributor.committeemember

• Luo, Xin
• Li, Liwu

• Alternaria alternata
• Alt a1
• bone marrow dendritic cells
• Innate immunity
• Th17

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:15897

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/83811