IL-4 and IL-13 expression in chronic sinusitis: relationship with cellular infiltrate and effect of topical corticosteroid treatment.
OBJECTIVE
Chronic sinusitis with allergy (ACS) and without allergy (NCS) are inflammatory diseases with considerable morbidity. The present study was undertaken to investigate, by in situ hybridization, the expression of IL-13 and IL-4 mRNA in sinus biopsy sections.


METHODS
Specimens were obtained from subjects with NCS (n = 12), ACS (n = 13), ACS on steroid therapy (n = 11), and normal controls (n = 11). The composition of the inflammatory infiltrate was also examined in all cases.


RESULTS
The number of cells expressing IL-4 and IL-13 transcripts was significantly higher in subjects with ACS compared to normal controls. In contrast, the numbers of IL-13 but not IL-4 mRNA-positive cells were increased in the NCS subjects compared to the normal controls. IL-4 and IL-13 mRNA expression was suppressed in ACS subjects on topical steroid therapy compared to untreated patients. There was no significant difference in the numbers of eosinophils between the ACS subjects treated with steroids and those who were not treated, but the steroid-treated patients demonstrated significantly higher numbers of CD8+ cells in the sinus mucosa. Increased numbers of CD8+ cells were also observed in subjects with NCS compared with ACS subjects and normal controls.


CONCLUSIONS
These results demonstrate that increased IL-13 expression is an important feature of allergic and nonallergic patients with chronic sinusitis. Furthermore, our data indicate that IL-13 and IL-4 are under differential regulation in NCS subjects.
al Ghamdi
K
K
McGill Nasal Research Group, SMBD-Jewish General Hospital, Montreal, Quebec.
Ghaffar
O
O
Small
P
P
Frenkiel
S
S
Hamid
Q
Q
D000293:Adolescent; D000328:Adult; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D017252:CD3 Complex / Q000276:immunology; D016827:CD8 Antigens / Q000276:immunology; D002908:Chronic Disease; D004804:Eosinophils / Q000276:immunology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D018793:Interleukin-13 / Q000276:immunology*; D015847:Interleukin-4 / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger; D012221:Rhinitis, Allergic, Perennial / Q000276:immunology; D012852:Sinusitis / Q000188:drug therapy* / Q000276:immunology*; D013256:Steroids; D013601:T-Lymphocytes
D000893:Anti-Inflammatory Agents; D017252:CD3 Complex; D016827:CD8 Antigens; D018793:Interleukin-13; D012333:RNA, Messenger; D013256:Steroids; D015847:Interleukin-4