[Expressions of immunoglobulin E, interleukin-5 and granulocyte-macrophage colony-stimulation factor in nasal polyps tissue]

Abstract

Objective: The study was designed to examine the suggested roles of Immunoglobulin E (IgE), Interleukin-5 (IL-5) and Granulocyte-macrophage colony-stimulation factor (GM-CSF) in the pathogenesis of eosinophil accumulation in nasal polyps (NP) and to understand the correlations between IgE and IL-5/GM-CSF in NP.

Method: Nasal polyps (n=31) and healthy nasal mucosa samples (n=11) were taken during routine endonasal surgeries. The tissue-bound IgE was measured with a sequential two-step immunoenzymatic (Sandwich) assay (Access immunoassay system, Beckman, USA). IL-5 and GM-CSF concentrations were measured with ELISA technique in homogenized polyp tissue and in control mucosa, and the number of eosinophils was counted in the corresponding tissue with hematoxylin eosin staining.

Result: The level of tissue-bound IgE, IL-5 and GM-CSF was significantly higher in NP compared with control specimens (P<0.01). There was significant correlation between tissue IgE/IL-5/GM-CSF and the number of eosinophils in the NP group (r=0.73, 0.54, 0.48, P<0.01). The correlation between concentration of IgE and IL-5/GM-CSF was also significant in nasal polyp group (r=0.65, 0.42, P<0.01 and P<0.05).

Conclusion: This study demonstrated that the tissue-bound IgE, IL-5 and GM-CSF played an important role in the recruitment of eosinophils in NP. A local upregulation of the IgE synthesis in comparison with control group suggests that the immunologic pathway or local allergy involved in the recruitment of eosinophils in NP. A local upregulation of the IgE may play an important role in the upregulation of IL-5 and GM-CSF in NP.