MEX3B inhibits collagen production in eosinophilic nasal polyps by downregulating epithelial cell TGFBR3 mRNA...

Area of Science:

• Immunology
• Molecular Biology
• Otorhinolaryngology

Background:

• Mex3 RNA-binding family member B (MEX3B) expression is elevated in eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP).
• The function of MEX3B in airway epithelial cells is not well understood.

Purpose of the Study:

• To investigate the role of MEX3B in different subtypes of chronic rhinosinusitis (CRS).
• To elucidate the molecular mechanism by which MEX3B affects airway epithelial cells and its relevance to CRSwNP.

Main Methods:

• Analysis of MEX3B expression in human nasal epithelial cells (HNECs) from CRS subtypes.
• Investigating MEX3B's interaction with TGF-β receptor III (TGFBR3) mRNA.
• Assessing the impact of MEX3B manipulation on TGF-β2 signaling and collagen production in HNECs.
• Correlating molecular findings with clinical features of CRSwNP.

Main Results:

• MEX3B binds to the 3' UTR of TGFBR3 mRNA, reducing its stability and expression in HNECs.
• TGF-βR3 acts as a TGF-β2-specific coreceptor in HNECs.
• MEX3B levels inversely correlate with TGFBR3 and phosphorylated SMAD2 in CRSwNP, particularly the eosinophilic subtype.
• TGF-β2-induced collagen production is modulated by MEX3B and TGFBR3 levels.
• Collagen expression is negatively correlated with MEX3B and positively with TGFBR3 in eosinophilic CRSwNP.

Conclusions:

• MEX3B inhibits tissue fibrosis in eosinophilic CRSwNP by downregulating epithelial TGFBR3 expression.
• MEX3B plays a protective role against fibrosis in eosinophilic CRSwNP.
• MEX3B represents a potential therapeutic target for treating eosinophilic CRSwNP.