Clinical severity and epithelial endotypes in chronic rhinosinusitis

Area of Science:

• Immunology
• Otolaryngology
• Respiratory Medicine

Background:

• Chronic rhinosinusitis (CRS) is a complex inflammatory condition of the upper airway.
• The relationship between clinical disease severity and specific epithelial inflammatory markers remains unclear.
• Prior research often focused on polyps or eosinophilia, overlooking other epithelial-derived cytokines.

Purpose of the Study:

• To investigate the association between epithelial-derived cytokines (IL-25, IL-33, TSLP) and eotaxin-3 with clinical markers of CRS severity.
• To compare gene expression of these mediators with symptom scores, radiology, endoscopy, and serological markers.
• To explore potential links with reactive airways disease (RAD) and atopy.

Main Methods:

• Quantitative PCR was used to measure mRNA expression of IL-25, IL-33, TSLP, and eotaxin-3 in sinus mucosal samples from CRS patients and controls.
• Gene expression data were correlated with clinical parameters including symptom, radiology (CT), and endoscopy scores, serum eosinophil counts, RAD, and atopy.
• Patients undergoing sinus surgery (CRS with and without polyps) and tumor patients with normal mucosa (controls) were included.

Main Results:

• The CRSwNP (CRS with nasal polyps) phenotype was associated with elevated IL-25, IL-33, and eotaxin-3.
• Increased eotaxin-3 correlated significantly with worse CT and endoscopic scores.
• Elevated IL-25 correlated with poorer CT scores and higher serum eosinophil counts.

Conclusions:

• Epithelial inflammatory mediators in CRS show some correlation with established measures of disease burden.
• Specific epithelial cytokine profiles may indicate a dysfunctional epithelial barrier in CRS.
• Further research and endotyping of CRS epithelium could offer prognostic insights and guide treatment strategies.