Expression of interleukin 4 receptors in bronchial asthma patients who underwent specific immunotherapy

Interleukin (IL) 4 and IL-13 are crucial cytokines for the development of allergic reactions and have been shown to modulate the function of monocytes and macrophages.

To evaluate the expression of IL-4Rs on peripheral blood monocytes and in the serum of patients with bronchial asthma who underwent specific immunotherapy (SIT).

The study was performed on 17 asthma patients with a typical clinical history and positive skin prick test results to Dermatophagoides pteronyssinus allergens. Five asthma patients who declined SIT were used as a comparator control group. Ten healthy persons served as negative controls. Flow cytometry analysis was performed on the whole blood samples using labeled monoclonal antibodies against CD14 and CD36 monocyte markers and against the CD124 alpha chain of IL-4R. The serum levels of soluble IL-4R were evaluated using an immunoenzymatic assay.

Compared with controls, bronchial asthma patients before SIT had a higher mean +/- SD percentage of CD14-positive cells that coexpressed CD124 (3.5% +/- 1.8% vs 18.6% +/- 7.9%; P < .01). After SIT, the mean +/- SD percentage of CD14 cells coexpressing CD124 decreased to 8.1% +/- 5.1%, which was significantly lower than before SIT (P < .01) but still significantly higher than in controls (P = .01). Changes in CD124 expression were associated with up-regulation of CD14 and down-regulation of CD36 expression on peripheral blood monocytes, suggesting that IL-4/IL-13-mediated signaling may be important for regulation of monocyte phenotype and function in asthma patients receiving SIT.

Even short courses of SIT are associated with a decrease in IL-4R expression on peripheral blood monocytes, which may cause decreased IL-4/IL-13-mediated effects in patients who undergo SIT.