Distinct Secretion of MUC5AC and MUC5B in Upper and Lower Chronic Airway Diseases

Said Ahmad Shah; Hajime Ishinaga; Kazuhiko Takeuchi

doi:10.3889/oamjms.2022.8060

Authors

Said Ahmad Shah Department of Otorhinolaryngology, Head and Neck Surgery, Mie University Graduate School of Medicine, Mie, Japan https://orcid.org/0000-0002-1895-3067
Hajime Ishinaga Department of Otorhinolaryngology, Head and Neck Surgery, Mie University Graduate School of Medicine, Mie, Japan
Kazuhiko Takeuchi Department of Otorhinolaryngology, Head and Neck Surgery, Mie University Graduate School of Medicine, Mie, Japan https://orcid.org/0000-0001-6855-6425

DOI:

https://doi.org/10.3889/oamjms.2022.8060

Keywords:

MUC5AC/MUC5B hypersecretion, Goblet cell hyperplasia, Submucosal gland hypertrophy, Chronic airway diseases, Mechanisms/pathways

Abstract

The human airway is protected by a defensive mucus barrier. The most prominent components of mucus are the mucin glycoproteins MUC5AC and MUC5B. They are produced by goblet cells and submucosal gland cells in the upper and lower airways. Hyperplasia of these cells and hypersecretion of MUC5AC and MUC5B characterize chronic inflammatory diseases of the upper and lower airways. Recent studies have revealed that MUC5AC and MUC5B are expressed at specific sites in the respiratory tract through different molecular mechanisms and have distinct functions. Morphometric and histochemical studies have also examined the roles of goblet cells, submucosal gland cells, MUC5AC, and MUC5B in different chronic airway diseases individually. The individual study of goblet cells, submucosal gland cells, MUC5AC, and MUC5B in airway diseases would be helpful for precisely diagnosing chronic inflammatory diseases of the airway and establishing optimal treatments. This review focuses on the distinct secretion of MUC5AC and MUC5B and their producing cells in chronic inflammatory diseases of the upper and lower airway.

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