Surfactant protein B detection and gene expression in chronic rhinosinusitis.
BACKGROUND
Surfactant protein (SP)-B is a hydrophobic protein secreted within pulmonary surfactant that facilitates the adsorption of surface-active lipids to the air-liquid interface of the alveoli and increases alveolar stability. SP-B may also have anti-inflammatory properties. It is implicated in decreasing the pulmonary inflammatory response to bacterial lipopolysaccharide. However, the expression and function of SP-B in the sinonasal cavities has not been elucidated. Our objective was to detect the presence of SP-B, measure alterations in several forms of chronic rhinosinusitis (CRS), and localize cellular protein expression.


METHODS
Sinus mucosal biopsies were performed in patients with allergic fungal rhinosinusitis (AFRS), nonatopic CRS with nasal polyposis (NP), and cystic fibrosis (CF) and in healthy controls. SP-B mRNA was measured in CRS and control patients using quantitative polymerase chain reaction. Immunoblot analysis and immunolocalization of SP-B were also performed.


RESULTS
CF (n = 4) showed significantly increased levels of SP-B (169-fold) mRNA (P = .004) when compared with controls (n = 5). CRS with NP (n = 5) and AFRS (n = 7) also demonstrated elevated levels of SP- B (14-fold and 4-fold, respectively) when compared with the control group, although these were not statistically significant. Immunoblot analysis confirmed the presence of the translated product, and immunolocalization revealed expression in the epithelium and submucosal glandular elements.


CONCLUSIONS
This is the first study to detect and characterize SP-B in human sinus mucosa. Furthermore, SP-B is significantly up-regulated in CF CRS.
Woodworth
Bradford A
BA
Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania Health System, Philadelphia, Pennsylvania 19104, USA. Bradford.Woodworth@uphs.upenn.edu
Wood
Rachel
R
Bhargave
Geeta
G
Cohen
Noam A
NA
Baatz
John E
JE
Schlosser
Rodney J
RJ
D000906:Antibodies / Q000276:immunology; D001706:Biopsy; D002908:Chronic Disease; D003550:Cystic Fibrosis / Q000378:metabolism / Q000473:pathology; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D009297:Nasal Mucosa / Q000378:metabolism / Q000473:pathology; D037701:Pulmonary Surfactant-Associated Protein B / Q000235:genetics* / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D020545:Respiratory Mucosa / Q000276:immunology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012221:Rhinitis, Allergic, Perennial / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology
D000906:Antibodies; D018076:DNA, Complementary; D037701:Pulmonary Surfactant-Associated Protein B; D012333:RNA, Messenger