Concentration, distribution and expression of interleukin-5 in human nasal polyp tissues.
OBJECTIVE
To study the concentration, distribution and expression of IL-5 in nasal polyp tissues and explore its significance in micro-environment differentiation of eosinophil accumulation.


METHODS
The concentration and expression of IL-5 in nasal polyp tissues of 40 patients were determined by ELISA and immunohistochemistry and inferior turbinate mucosa from patients with nasal polyps and healthy volunteers were used as control.


RESULTS
IL-5 concentration in polyp tissues was significantly higher than that in turbinate mucosa (P < 0.05). There was no significant difference in the turbinate mucosae between patients with nasal polyps and healthy volunteers (P > 0.05). IL-5 concentrations in polyp tissues were markedly higher in patients with allergic rhinitis compared with those without (P < 0.05). IL-5 concentrations had no correlation with age and sex (P > 0.05). 80.1% of the eosinophils were positive for IL-5 and 90.9% of IL-5 positive cells were eosinophils. Only 3.7% of lymphocytes and neutrophils were positive for IL-5; IL-5 was not detectable in epithelial cells. IL-5 expression in eosinophils of polyp tissues was remarkably stronger than that of the turbinate mucosa (P < 0.05); there was no significant difference in the the turbinate mucosae between patients with nasal polyps and healthy volunteers (P > 0.05). IL-5 expression of eosinophils in polyp tissue was significantly stronger in patients with allergic rhinitis compared with those without (P < 0.05). There was no significant difference in IL-5 expression in lymphocytes and neutrophils between polyp tissues and turbinate nasal mucosa (both P > 0.05).


CONCLUSIONS
IL-5 is the key cytokine in eosinophilic pathologic mechanisms in nasal polyp tissues.
Xu
Rui
R
Department of Otolaryngology, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China. yinxy@gzsums.edu.cn
Li
Yuan
Y
Xie
Minqiang
M
Xu
Geng
G
Zhang
Gehua
G
Wang
Shufang
S
D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D004804:Eosinophils / Q000737:chemistry; D005260:Female; D006801:Humans; D015848:Interleukin-5 / Q000032:analysis*; D008214:Lymphocytes / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000737:chemistry; D009298:Nasal Polyps / Q000276:immunology*; D014420:Turbinates / Q000737:chemistry
D015848:Interleukin-5