Abstract
Background. The ability of epithelial cells (ECs) to discriminate between commensal and pathogenic microbes is essential for healthy living. Key to these interactions are mucosal epithelial responses to pathogen-induced damage.Methods. Using reconstituted oral epithelium, we assessed epithelial gene transcriptional responses to Candida albicans infection by microarray. Signal pathway activation was monitored by Western blotting and transcription factor enzyme-linked immunosorbent assay, and the role of these pathways in C. albicans–induced damage protection was determined using chemical inhibitors.Results. Transcript profiling demonstrated early upregulation of epithelial genes involved in immune responses. Many of these genes constituted components of signaling pathways, but only NF-κB, MAPK, and PI3K/Akt pathways were functionally activated. We demonstrate that PI3K/Akt signaling is independent of NF-κB and MAPK signaling and plays a key role in epithelial immune activation and damage protection via mammalian target of rapamycin (mTOR) activation.Conclusions. PI3K/Akt/mTOR signaling may play a critical role in protecting epithelial cells from damage during mucosal fungal infections independent of NF-κB or MAPK signaling.
Highlights
The ability of epithelial cells (ECs) to discriminate between commensal and pathogenic microbes is essential for healthy living
We demonstrate that phosphoinositide 3 kinase (PI3K)/Akt signaling is independent of NF-κB and mitogenactivated protein kinase (MAPK) signaling and plays a key role in epithelial immune activation and damage protection via mammalian target of rapamycin activation
PI3K/Akt/mammalian target of rapamycin (mTOR) signaling may play a critical role in protecting epithelial cells from damage during mucosal fungal infections independent of NF-κB or MAPK signaling
Summary
We assessed epithelial gene transcriptional responses to Candida albicans infection by microarray. Signal pathway activation was monitored by Western blotting and transcription factor enzyme-linked immunosorbent assay, and the role of these pathways in C. albicans–induced damage protection was determined using chemical inhibitors. Cell Lines and Reagents All monolayer experiments were performed using the TR146 buccal epithelial carcinoma cell line. Cells were serum starved overnight and infections performed in serum-free conditions. Reconstituted human oral epithelium (ROE) created using TR146 cells was purchased from SkinEthic Laboratories and used as previously described [10]. Antibodies to phospho-c-Jun, phospho-MKP1 phospho-Akt, phospho-PDK1, phospho-IκBα, phospho-GSK3β, phospho-IRF3, phospho-STAT3, and c-Fos were purchased from Cell Signaling Technologies (New England Biolabs). The C. albicans SC5314 strain was used in all experiments [11, 17]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
