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Recent Insights into Cellular Crosstalk in Respiratory and Gastrointestinal Mucosal Immune Systems

  • Sae-Hae Kim (Department of Molecular Biology and The Institute for Molecular Biology and Genetics, Jeonbuk National University) ;
  • Yong-Suk Jang (Department of Molecular Biology and The Institute for Molecular Biology and Genetics, Jeonbuk National University)
  • Received : 2020.08.29
  • Accepted : 2020.10.18
  • Published : 2020.12.31

Abstract

The human body is continuously threatened by pathogens, and the immune system must maintain a balance between fighting infection and becoming over-activated. Mucosal surfaces cover several anatomically diverse organs throughout the body, such as the respiratory and gastrointestinal tracts, and are directly exposed to the external environment. Various pathogens invade the body through mucosal surfaces, making the mucosa the frontline of immune defense. The immune systems of various mucosal tissues display distinctive features that reflect the tissues' anatomical and functional characteristics. This review discusses the cellular components that constitute the respiratory and gastrointestinal tracts; in particular, it highlights the complex interactions between epithelial and immune cells to induce Ag-specific immune responses in the lung and gut. This information on mucosal immunity may facilitate understanding of the defense mechanisms against infectious agents that invade mucosal surfaces, such as severe acute respiratory syndrome coronavirus 2, and provide insight into effective vaccine development.

Keywords

Acknowledgement

This study was supported by grants from the Basic Science Research Programs (NRF-2019R1A2C2004711) through the National Research Foundation, funded by Korean Ministry of Science and ICT, and by the Basic Science Research Program through the NRF, funded by the Ministry of Education (2017R1A6A1A03015876). Dr. Yong-Suk Jang was supported by the Research Base Construction Fund Support Program funded by Jeonbuk National University in 2020.

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