The Effect of Allergen-Specific Immunotherapy on IL-10 and IL-13 mRNA Expression in Peripheral Blood Mononuclear Cells from Patients with Atopic Asthma

Lee, Soo Jung; Lee, Joon Sung; Lee, Kyong Su

Abstract

PURPOSE
Allergen-specific immunotherapy (IT) has been shown to be effective in the treatment for allergic diseases. But the immunologic mechanism of IT effect has not been fully elucidated. We studied house dust mite (HDM)-specific cytokine mRNA expression in peripheral blood mononuclear cells (PBMC) from patient with HDM- sensitive asthma and determined whether alterations in cytokine mRNA expression correlated with the clinical outcome of IT.
METHODS
PBMC were obtained from 64 children with mite-sensitive asthma : 25 had never received HDM-IT (NIT), 39 had been receiving HDM-IT for more than 12 months. The 39 patients were divided into two groups according to the clinical response based on the asthma scores (symptom and medication scores) before and after IT. Good responders were those patients who showed an improvement greater than 50%, whereas poor responders were those who showed an improvement less than 50%. After a 18 hr culture with HDM, cytokine mRNA expression was analysed by RT-PCR and densitometry.
RESULTS
1) IL-10 mRNA expression in NIT was significantly lower than that in the normal controls and was significantly increased by IT. IL-10 mRNA expression in the good responders was significantly higher than that in the poor responders and NIT. 2) Little or no IL-13 mRNA were detected in the good responders and the normal controls. IL-13 mRNA expression in the good responders was significantly lower than that in the poor responders and NIT. 3) IFN-gamma mRNA expression in NIT was significantly lower than that in the normal controls and was significantly increased with IT. IFN-gamma mRNA expression in the good responders was significantly higher than that in the poor responders and NIT. 4) Little IL-4 mRNA were detected in the good responders and the normal controls. IL-4 mRNA expression in the good responders was significantly lower than that in the poor responders and NIT.
CONCLUSION
These results show that IT not only induces a shift in cytokine expression from TH2 (IL-4 and IL-13) to TH1 cytokines (IFN-gamma), but also leads to induction of the antiinflammatory cytokine IL-10. These changes in cytokine expression may be responsible for clinical effects by immunotherapy.