Expression and immunolocalization of CFTR in the human gingiva

OBJECTIVES: Cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated chloride channel that regulate electrolyte and water transport across epithelia, mutations of which are responsible for the hallmarks of cystic fibrosis (CF), the most common autosomal recessive disorder in Caucasians is expressed in many epithelia including those lining the gastrointestinal tract where it is involved in transepitelial transport of fluid and electrolytes. However, there is no report of CFTR expression in the epithelial lining of the oral cavity. It appears possible that CFTR may also be expressed in the oral epithelium including those of the gingiva. The gingival sulcus epithelium produces gingival crevicular fluid (GCF) that may increase in volume on stimulus. However, the origin and transport of GCF across gingival epithelium is currently unknown. The present study investigated the expression and localization of CFTR in the human gingiva. METHODS: We used reverse transcriptase – polymerase chain reaction (RT-PCR), immunohistochemistry and immunofluorescence staining for CFTR expression and localization in healthy human gingiva and reconstituted human gingival epithelial tissues model. RESULTS: RT-PCR revealed that CFTR mRNA is expressed in the human gingiva. Immunostaining localized CFTR protein on the apical membrane of human gingiva epithelium and reconstituted human gingival epithelial tissue model. CONCLUSIONS: These results indicate that CFTR is expressed in human gingiva and reconstituted human gingival epithelial tissues. CFTR expression in human gingiva provides molecular evidence for GCF formation, may be involved in the pathogenesis of periodontal diseases and oral mucosal immunity.