Fig. 1

Gating strategy for flow cytometric identification of CD4⁺CD25^highCD127^- regulatory T-cells in the peripheral blood. a Lymphocytes were identified based on their characteristic properties shown in the forward scatter (FSC) and sideward scatter (SSC). b A representative gating was set for CD4⁺ T cells from blood lymphocytes. c A representative dot plots showing expression of CD25^highCD127^- regulatory T-cells in blood CD4⁺ T-cells of a never-smoker healthy volunteer (NSHV). d A representative dot plots showing expression of CD25^highCD127^- regulatory T-cells in blood CD4⁺ T-cells of a current smoker healthy volunteer (CSHV). e A representative dot plots showing expression of CD25^highCD127^- regulatory T-cells in blood CD4⁺ T cells of a former smoker COPD patient (FSC). f A representative dot plots showing expression of CD25^highCD127^- regulatory T-cells in blood CD4⁺ T-cells of a current smoker COPD patient (CSC)