Abstract: Objective: To detect the interleukin-22(IL-22) levels in peripheral blood of the asthma patients and analyze the relationship between the IL-22 levels and IgE,pulmonary function,fractional exhaled nitric oxide(FENO),and to investigate the role of IL-22 in the pathogenesis of bronchial asthma. Methods: Seventy-eight patients with asthma were selected as experiment group. The asthma patients were divided into increased IgE group (n=46)and normal IgE group(n=32)according to the IgE levels.The asthma patients were also divided into acute attack stage and clinical control stage according to patients' clinical symptoms.In addition, twenty healthy controls were chosen as healthy control group. The plasma IL-22 levels, IgE,forced expiratory volume in one second (FEV1) and FENO levels of the subjects in various groups were detected and compared between various groups. The correlations between the plasma IL-22 levels and IgE, FEV1,FENO were analyzed. Results: The plasma IL-22 level and FENO level of the patients in asthma group were higher than those in healthy control group(P<0.05).The IL-22 level and FENO level of the patients in clinical control stage were lower than those in acute attack stage,but they were still higher than those in healthy control group(P<0.05).The plasma IL-22 level of the patients in increased IgE group was higher than that in normal IgE group(P<0.05). There were significant negative correlations between the IL-22 levels and FEV1 in the asthma patients in acute attack group and clinical control group(r=-0.365 3,P<0.05;r=-0.267 2,P<0.05),but there was no significant correlation between the IL-22 levels and FENO(r=0.011 9,P>0.05;r=0.059 8,P>0.05). Conclusion: The increased expression of IL-22 in peripheral blood of the patients with asthma may participate in the pathogenesis of asthma,and may aggravate the deterioration of pulmonary function of the asthma patients.

Key words: immunoglobulin E, bronchial asthma, interleukin-22, pulmonary function, fractional exhaled nitric oxide