title: Clara cell 10-kD protein in inflammatory upper airway diseases.
abstract: OBJECTIVE
  To discuss the role of Clara cell 10-kD protein (CC10), an anti-inflammatory and immunomodulatory molecule, in inflammatory upper airway diseases, particularly in allergic rhinitis and chronic rhinosinusitis (CRS).
  
  
  RESULTS
  CC10 expression is downregulated in allergic rhinitis and CRS. CC10 can inhibit the expression of chitinase 3-like 1 protein and osteopontin in eosinophilic CRS and allergic rhinitis, respectively. CC10 can also suppress osteopontin-induced expression of Th2 and proinflammatory cytokines in airway epithelial cells, and CC10 gene transfection can inhibit NF-κB activity in airway epithelial cells. Proinflammatory and Th2 cytokines can diminish CC10 production, whereas Th1 cytokines and interleukin-10 can promote CC10 production in sinonasal mucosa. Allergen exposure leads to a transdifferentiation of CC10 secreting cells into trefoil factor family 1 secreting cells and/or goblet cells in upper airways, resulting in the diminished expression of CC10.
  
  
  CONCLUSIONS
  Allergen exposure and Th2 milieu can suppress the expression of CC10 in upper airways. CC10 can inhibit Th2-dominated eosinophilic inflammation in upper airways via multiple pathways.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002908:Chronic Disease; D005786:Gene Expression Regulation; D006801:Humans; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000209:etiology*; D012852:Sinusitis / Q000209:etiology*; D014598:Uteroglobin / Q000032:analysis / Q000235:genetics / Q000502:physiology*
chemical_list: C556389:SCGB1A1 protein, human; D014598:Uteroglobin