Decreased percentage of CD4+Foxp3+TGF-β+ and increased percentage of CD4+IL-17+ cells in bronchoalveolar lavage of asthmatics

Background: asthma is a chronic inflammatory disorder of the airways with the proven role of th2 cells in its pathogenesis. the role and characteristic of different subsets of cd4+ cells is much less known.aim. the aim of the study was to analyze the incidence of different subsets of cd4+ t cells,in particular different subsets of cd4+ cells with the co-expression of different cytokines.methods. twenty five stable asthmatic and twelve age-matched control subjects were recruited to the study. bronchoscopy and bronchoalveolar lavage (bal) were performed in all study subjects. cd4+ t cells were isolated from bal fluid by positive magnetic selection. after stimulation simultaneous expression of tgf-β,foxp3,cd25,ifn-γ,il-4,tnf-α (set 1); il-10,foxp3,cd25,ifn-γ,il-4,mip-1β (set 2); il-17a,il-8,ifn-γ,il-4,mip-1β (set 3) were measured by flow cytometry.results: the percentage of cd4+ cells co-expressing foxp3 and tgf-β (cd4+foxp3+tgf-β+ cells) was significantly lower (p = 0.03),whereas the percentage of cd4+il-17+ cells (p = 0.008),cd4+il-17+ ifn-γ+ cells (p = 0.047) and cd4+il-4+ cells (p = 0.01) were significantly increased in asthmatics compared with that seen in healthy subjects. a significantly higher percentage of cd4+foxp3+ cells from asthma patients expressed ifn-γ (p = 0.01),il-4 (p = 0.004) and cd25 (p = 0.04),whereas the percentage of cd4+il-10+ cells expressing foxp3 was significantly decreased in asthmatics (p = 0.03). fev1% predicted correlated negatively with the percentage of cd4+il-17+ cells (r = -0.33; p = 0.046) and positively with cd4+foxp3+tgf-β+ cells (r = 0.43; p = 0.01).conclusions: our results suggest that in the airways of chronic asthma patients there is an imbalance between increased numbers of cd4+il-17+ cells and th2 cells and decreased number of cd4+foxp3+tgf-β+. © 2014barczyk et al.; licensee biomed central ltd.