Expression Of Aryl Hydrocarbon Receptor And Interleukin 22 In Peripheral Blood Of Patients With Bronchial Asthma

Objectives: We sought to determine whether the expression of aryl hydrocarbon receptor (AhR) and interleukin (IL)-22 may change in peripheral blood of patients with bronchial asthma and whether the expression of them may be relative to objective indices presenting the severity of the disease .Methods: Blood samples were obtained from each subject of asthma exacerbation (n = 18), asthma remission (n = 17) and healthy control (n = 12) respectively. The peripheral blood mononuclear cells (PBMCs) were collected for AhR mRNA detection by real-time quantitative polymerase chain reaction (RT-PCR). The plasma was collected for IL-22 protein detection by enzyme-linked immunosorbent assay (ELISA). Lung function and asthma severity score (ASS) of each subject was measured and we analyzed the relation between expression level of IL-22 protein and expression level of AhR mRNA, lung function and ASS of patients.Results: The expression of AhR mRNA in PBMCs and IL-22 protein in plasma in patients with asthma exacerbation were higher than those in asthma remission and healthy control respectively(p<0.05). There was not statistical difference between asthma remission and healthy control in the levels of AhR mRNA and IL-22 protein, though those in asthma remission were slightly higher. There was no correlation between expression level of AhR mRNA and IL-22 in peripheral blood of patients in asthma exacerbation (p>0.05). The plasma concentrations of IL-22 had negative correlation to the predicted percentage of forced expiratory volume in the first second (FEV1%) and the percentage of FEV1 and forced vital capacity (FEV1/FVC%) of the disease(r=-0.51, r=-0.47,p<0.05 respectively), and it has a positive correlation to asthma severity score (ASS) of asthmatics(r=0.71,p<0.05).Conclusion: Increased expression level of both AhR mRNA and IL-22 protein in peripheral blood suggested that they might be involved in the pathogenesis of asthma in human, and the concentration of IL-22 protein in peripheral blood of patients might have some relation with the severity of the disease.