Abstract

Avian influenza virus (AIV) infections first affect the respiratory tract of chickens. The epithelial cells activate the host immune system, which leads to the induction of immune-related genes and the production of antiviral molecules against external environmental pathogens. In this study, we used chicken tracheal epithelial cells (TECs) in vitro model to investigate the immune response of the chicken respiratory tract against avian respiratory virus infections. Eighteen-day-old embryonic chicken eggs were used to culture the primary chicken TECs. Reverse transcription-polymerase chain reaction (RT-PCR) and immunocytochemistry (ICC) analysis of epithelial cell-specific gene makers were performed to confirm the characteristics, morphology, and growth pattern of primary cultured chicken TECs. Moreover, to investigate the cellular immune response to AIV infection or polyinosinic-polycytidylic acid (poly (I:C)) treatment, the TECs were infected with the H5N1 virus or poly (I:C). Then, immune responses were validated by RT-qPCR and western blotting. The TECs exhibited polygonal morphology and formed colony-type cell clusters. The RT-qPCR results showed that H5N1 infection induced a significant expression of antiviral genes in TECs. We found that TECs treated with poly (I:C) and exposed to AIV infection-mediated activation of signaling pathways, leading to the production of antiviral molecules (e.g., pro-inflammatory cytokines and chemokines), were damaged due to the loss of junction proteins. We observed the activation of the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, which are involved in inflammatory response by modulating the release of pro-inflammatory cytokines and chemokines in TECs treated with poly (I:C) and pathway inhibitors. Furthermore, our findings indicated that poly (I:C) treatment compromises the epithelial cell barrier by affecting junction proteins in the cell membrane. Our study highlights the utility of in vitro TEC models for unraveling the mechanisms of viral infection and understanding host immune responses in the chicken respiratory tract.

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 call

Disclaimer: 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.