TY - JOUR T1 - The potential mechanism of Th17/Treg imbalance in the microenvironments of chronic inflammation and allergic asthma JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P1950 AU - Linlin Wang Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P1950.abstract N2 - Objective Recent studies have shown that Tregs can differentiate into IL-17+Foxp3+T cells in the colitic microenvironment and allergic rhinitis. However, the biology of CD39+Treg cells, IL-17+Foxp3+T cells and Th17 cells, and the relationship among these three kinds of cells remain poorly understood in allergic asthma. Methods We investigated the proportions of Th17, CD39+Treg cells and IL-17+Foxp3+T cells in peripheral blood from allergic asthmatics and healthy controls by flow cytometry. All patients were allergic to house dust mites. Dermatophagoides pteronyssinus specific IgE levels, pulmonary function and Asthma Control Questionnaire were assessed. Moreover, the associations among all these kinds of index and disease severity were analyzed. Result There was a deficiency in the frequency of total Tregs in asthmatics, whereas the frequency of Th17 cells, IL-17+Foxp3+T cells, CD39+Treg cells and plasma IL-17 levels were increased in moderate to severe asthma. FEV1 (% predicted) was negatively correlated with the frequency of Th17 cells, IL-17+Foxp3+ T cells, CD39+Treg cells and plasma IL-17 levels, and positively correlated with the frequency of total Tregs. Moreover, the frequency of Th17 cells and IL-17+Foxp3+T cells were positively correlated with the frequency of CD39+Treg cells. Conclusion Our findings suggest that the increased expression of CD39 on Tregs in asthma can offset the other decreased immunosuppressive functions of Tregs. And Tregs in the microenvironment of asthma also have plasticity of differentiate into IL-17+Foxp3+T cells. CD39+Treg cells play an important role in constraining pathogenic Th17 cells and IL-17+Foxp3+T cells. ER -