Human beta-defensins and toll-like receptors in the upper airway.
BACKGROUND
Measurement of innate markers in nasal mucosa, tonsils and adenoids might lead to new views about the role of innate immunity in the upper airway. In this study, the expression of human beta-defensins (HBD) 2 and 3 and toll-like receptors (TLR) 2 and 4 in various upper airway diseases was investigated.


METHODS
Surgical samples from patients with tonsillar disease (n = 18), hypertrophic adenoids (n = 10) and sinonasal disease (n = 30) (chronic sinusitis, nasal polyps, turbinate mucosa as controls) were investigated by immunohistochemistry. Quantification of HBD-2 and 3 mRNA, TLR-2 and 4 mRNA expression was performed by real-time polymerase chain reaction (PCR).


RESULTS
Immunohistochemistry revealed a strong expression of HBD-2 in tonsillar tissue. Quantification of HBD-2 and HBD-3 mRNA showed a more than tenfold higher expression in tonsillar tissue than in adenoids, whereas in nasal biopsies, only negligible defensin expression could be measured. No significant differences were found for TLR-4 between the various tissues, whereas TLR-2 expression in adenoids was significantly lower compared with other tissues.


CONCLUSIONS
These results demonstrate a strong defensin expression in tonsillar tissue compared with nasal and paranasal mucosa and adenoids. Toll-like receptor expression in all these tissues illustrates a possibly important immunological sentinel function of upper airway mucosa.
Claeys
S
S
Department of Otorhinolaryngology, Ghent University, Ghent, Belgium.
de Belder
T
T
Holtappels
G
G
Gevaert
P
P
Verhasselt
B
B
van Cauwenberge
P
P
Bachert
C
C
D000233:Adenoidectomy; D000234:Adenoids / Q000276:immunology / Q000473:pathology; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006984:Hypertrophy; D018928:Immunity, Mucosal; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis*; D009297:Nasal Mucosa / Q000737:chemistry / Q000276:immunology; D014066:Palatine Tonsil / Q000276:immunology / Q000473:pathology; D010256:Paranasal Sinuses / Q000276:immunology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface / Q000032:analysis*; D020545:Respiratory Mucosa / Q000737:chemistry / Q000276:immunology*; D012852:Sinusitis / Q000276:immunology / Q000601:surgery; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D014068:Tonsillectomy; D023083:beta-Defensins / Q000032:analysis*
D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D023083:beta-Defensins