Different profiles of IL-10+IFN-gamma-IL-4-CD4+ T cells in the peripheral blood in atopic and non-atopic asthmatics.

摘要

BACKGROUND: The impaired production of interleukin (IL) 10 from regulatory T cells has been proposed as a causal mechanism of asthma. Although IL-10-producing (IL-10+) T cells are detectable in the peripheral blood, their significance in the pathophysiology of asthma remains uncertain. OBJECTIVES: This study aimed to investigate the profile of circulating IL-10+CD4+ T cells in atopic and non-atopic asthma. METHODS: Atopic and non-atopic asthmatics were divided into a mild and severe group. Their peripheral blood mononuclear cells (PBMCs) were stimulated with anti-CD3 and anti-CD28 antibodies and then processed for triple cytokine flow cytometry directed to IL-10, interferon (IFN) gamma and IL-4. RESULTS: IL-10+CD4+ cells were exclusively detected in the IFN-gamma-IL-4- population. In atopic asthma, the frequency of IL-10+IFN-gamma-IL-4-CD4+ cells in the severe group was significantly lower than that in the mild group. The frequency of IL-10+IFN-gamma-IL-4-CD4+ cells in the severe group was not significantly different from that in the mild group of those with non-atopic asthma. The frequency of IL-4+IFN-gamma-IL-10-CD4+ cells (Th2) was significantly higher in the group with mild atopic asthma than in that with mild non-atopic asthma. IFN-gamma+IL-4-IL-10-CD4+ cells (Th1) did not differ between groups, irrespective whether the subjects suffered from atopic or non-atopic asthma. CONCLUSIONS: IL-10+CD4+ cells in PBMCs may be distinct from Th1 or Th2 and likely have the profile of regulatory T cells. The differential association of IL-10+IFN-gamma-IL-4-CD4+ cells with clinical severity between atopic and non-atopic asthma implies that its pathophysiological significance may differ among asthma phenotypes.