Clara cell protein 16 release from the nasal mucosa in allergic rhinitis, chronic rhinosinusitis, and exposure to air pollutants

Headnote

[Received in December 2017; Similarity Check in December 2017; Accepted in September 2018]

Clara cell protein 16 (CC16) is a small protein mainly produced by non-ciliated Clara cells in the respiratory epithelium. It has an anti-inflammatory role in chronic upper and lower airway eosinophilic inflammations. Decreased levels of CC16 are found in the nasal secretions and plasma of patients with chronic eosinophilic inflammatory disorders, such as asthma, allergic rhinitis, and chronic rhinosinusitis with or without nasal polyps, as well as in people exposed to high levels of air pollutants. Intranasal corticosteroid administration suppresses chronic inflammation of the nasal mucosa driven by eosinophils and stimulates local CC16 production. CC16 can be a reliable biomarker of the beneficial effects of perennial allergic rhinitis and chronic rhinosinusitis therapy and of the functional recovery of the nasal mucosa after treatment with topical glucocorticoids.

KEY WORDS: glucocorticoids; inflammatory mediators; nasal polyps

Protein 16 Clara stanica (engl. Clara cell protein 16, krat. CC16) mali je protein kojega uglavnom stvaraju Clara stanice u respiratornom epitelu, koje nemaju cilije. Taj protein ima protuupalnu ulogu tijekom eozinofilnih upala gornjeg i donjeg dišnog puta. Niže koncentracije CC16 naðene su u nosnom sekretu i krvnoj plazmi pacijenata s kroničnim eozinofilnim upalnim bolestima, kao što su astma, alergijski rinitis i kronični rinosinuitis s nosnim polipima i bez njih, kao i u osoba koje su izložene onečišćenjima zraka. Primjena intranazalnih kortikosteroida blokira kroničnu eozinofilnu upalu nosne sluznice i stimulira lokalnu produkciju CC16. Protein CC16 može biti pouzdan biomarker ne samo poboljšanja funkcije nosne sluznice u pacijenata liječenih od perenijalnog alergijskog rinitisa i kroničnog rinosinuitisa nego i funkcionalnog oporavka nosne sluznice nakon terapije topikalnim glukokortikoidima.

KLJUČNE RIJEČI: glukokortikosteroidi; nosni polipi; posrednici upale

ALLERGIC RHINITIS AND CHRONIC RHINOSINUSITIS: DEFINITION, CLASSIFICATION, AND PATHOPHYSIOLOGY

Allergic rhinitis

Allergic rhinitis (AR) is a non-infectious chronic inflammatory disease of the nasal mucosa mediated by immunoglobulin E (IgE) in response to allergen exposure. What plays an essential role in the development of AR is the imbalance between T helper 1 and T helper 2 (Th1/Th2) cells, where the inflammation-mediating Th2 cells prevail (1). The disease most often presents itself as a noninfectious upper airway inflammation and affects between 10 and 30 % of people in Western Europe and North America.

According to clinical characteristics, AR...