Nasal epithelial cells express IL-10 at levels that negatively correlate with clinical symptoms in patients with house dust mite allergy.
BACKGROUND
Despite constant exposure to micro-organisms and other immunogenic environmental factors, relatively very few immunological responses are initiated in the nasal mucosa. Although several mechanisms could play a role in maintaining this immune suppressive milieu, none of them have been validated. Previous data from our group suggested that locally produced interleukin (IL)-10 could be involved in maintaining local homeostasis.


METHODS
To investigate the role of epithelial IL-10 expression in the manifestation of allergic symptoms, we used immunohistochemistry to study the expression of IL-10 in the nasal epithelium of healthy individuals and house dust mite allergic patients. In the allergic patients, we determined potential correlations of epithelial expression with allergic symptoms, both at baseline and after allergen provocation.


RESULTS
IL-10 is expressed in the basal and differentiated epithelial cells of both healthy individuals and allergic rhinitis patients. In the allergic individuals, there is a strong negative correlation at baseline between the epithelial expression level of IL-10 and rhinorrhoea and sneezing, but not between that expression level and nasal blockage or peak nasal inspiratory flow (PNIF). This correlation disappears with steroid treatment or after allergen provocation, although the expression at baseline seems to predict PNIF scores after provocation.


CONCLUSIONS
Our data not only reveals IL-10 expression by human nasal epithelial cells, but also suggests that nasal epithelial IL-10 regulates allergic symptoms. Targeting the regulation mechanisms affecting IL-10 or targeting the regulation mechanism affected by IL-10 could constitute new options for the treatment of allergic disease.
Muller
B
B
Department of Otorhinolaryngology, AMC, Amsterdam, The Netherlands.
de Groot
E J J
EJ
Kortekaas
I J M
IJ
Fokkens
W J
WJ
van Drunen
C M
CM
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000009:adverse effects*; D000730:Androstadienes / Q000627:therapeutic use; D018926:Anti-Allergic Agents / Q000627:therapeutic use; D039741:Antigens, Dermatophagoides / Q000009:adverse effects*; D005260:Female; D000068298:Fluticasone; D006801:Humans; D016753:Interleukin-10 / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000166:cytology / Q000276:immunology* / Q000503:physiopathology; D009299:Nasal Provocation Tests; D012221:Rhinitis, Allergic, Perennial / Q000188:drug therapy / Q000276:immunology*
D000485:Allergens; D000730:Androstadienes; D018926:Anti-Allergic Agents; D039741:Antigens, Dermatophagoides; D016753:Interleukin-10; D000068298:Fluticasone