Mucoglycoprotein hypersecretion in allergic rhinitis and cystic fibrosis

Area of Science:

• Respiratory Medicine
• Immunology
• Biochemistry

Background:

• Submucosal gland exocytosis plays a role in airway secretions.
• Specific changes in mucoglycoconjugates during allergic rhinitis (AR), nonallergic rhinitis (NAR), and cystic fibrosis (CF) are not well understood.
• Mucoglycoconjugates are complex carbohydrates involved in mucus properties and host defense.

Purpose of the Study:

• To investigate and compare submucosal gland exocytosis markers in AR, NAR, and CF.
• To quantify specific mucoglycoconjugates in nasal secretions from different rhinitis and CF patient groups.
• To characterize the molecular properties of identified mucoglycoconjugates.

Main Methods:

• Collected nasal lavage fluids from healthy controls, AR, NAR, and CF subjects.
• Measured concentrations of lysozyme, Alcian blue-staining mucoglycoconjugate material (AB + m), and 7F10-immunoreactive mucoglycoconjugates (7F10-irm).
• Characterized AB + m and 7F10-irm using Sepharose-2B chromatography and glycosidase digestion.

Main Results:

• 7F10-irm levels were significantly elevated in CF (2.4-fold) and AR (12.7-fold) compared to controls.
• AB + m levels showed a trend towards increase in CF (1.8-fold) and AR (1.2-fold), but not significantly in NAR.
• 7F10-irm and AB + m are distinct sialylated mucoglycoproteins, with 7F10-irm showing significant induction in AR and CF.

Conclusions:

• Allergic rhinitis and cystic fibrosis exhibit distinct alterations in specific mucoglycoconjugate secretion.
• 7F10-irm is a sensitive marker for increased submucosal gland exocytosis in AR and CF.
• Nonallergic rhinitis does not show significant changes in these measured mucoglycoconjugates.