Gene and protein expression of protease-activated receptor 2 in structural and inflammatory cells in the nasal mucosa in seasonal allergic rhinitis.
BACKGROUND
Protease-activated receptor 2 (PAR 2) has been shown to be responsible for trypsin and mast cell tryptase-induced airway inflammation. Here, the present study aimed to explore the expression of PAR 2 in the nasal mucosa of seasonal allergic rhinitis (SAR).


METHODS
Study subjects were recruited for the study by medical history, physical examination and laboratory screening tests. Using immunohistochemistry, laser-assisted cell picking and subsequently real-time PCR, nasal mucosa biopsies of SAR patients were investigated for PAR 2 gene and protein expression in complex tissues of the nasal mucosa.


RESULTS
Gene and protein expression of PAR 2 was firstly detected in nasal mucosa of SAR patients. The relative gene expression level of PAR 2 was significantly increased in complex tissues of the nasal mucosa of SAR (6.21+/-4.02 vs. controls: 1.38+/-0.86, P=0.004). Moreover, PAR 2 mRNA expression in epithelial cells (SAR: 4.78+/-4.64 vs. controls: 0.84+/-0.61, P=0.003) but not in mucus (SAR: 1.51+/-1.15 vs. controls: 1.35+/-1.02, P=0.78) and endothelial cells (SAR: 1.20+/-0.57 vs. controls: 1.73+/-1.30, P=0.5) was found to be significantly changed in the nasal mucosa in SAR. Using double immunohistochemistry the present study demonstrated that the total numbers of mast cells (P=0.0003) and eosinophils (P=0.03) and the numbers of eosinophils expressing PAR 2 (P=0.006) were significantly elevated in the nasal mucosa of SAR compared with the controls.


CONCLUSIONS
The abundant presence and distribution of gene and protein expression of PAR 2 in different cell types in the nasal mucosa under normal situation, the increased expression of PAR 2 in epithelial cells and the increased number of eosinophils with PAR 2 suggest that PAR 2 may contribute to the pathogenesis of allergic diseases such as SAR.
Dinh
Q T
QT
Department of Internal Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany. q-thai.dinh@charite.de
Cryer
A
A
Trevisani
M
M
Dinh
S
S
Wu
S
S
Cifuentes
L B
LB
Feleszko
W K
WK
Williams
A
A
Geppetti
P
P
Fan Chung
K
K
Heppt
W
W
Klapp
B F
BF
Fischer
A
A
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D004804:Eosinophils / Q000737:chemistry*; D004847:Epithelial Cells / Q000737:chemistry / Q000276:immunology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007958:Leukocyte Count; D008297:Male; D008407:Mast Cells / Q000737:chemistry*; D008875:Middle Aged; D009297:Nasal Mucosa / Q000737:chemistry* / Q000276:immunology; D044464:Receptor, PAR-2 / Q000032:analysis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology / Q000378:metabolism*
D044464:Receptor, PAR-2