Figure 1.

CM populations in the periphery are similar to those found in the airway. (A) Gating strategy for polychromatic flow cytometry analysis of blood monocyte subsets. After exclusion of debris and selecting live, CD45⁺ cells, peripheral blood mononuclear phagocytes were identified as Lin⁻ (CD3, CD4, CD8, CD19, CD20, CD34, and FCεRI), HLA-DR⁺cells which were either CD14⁺CD16⁻ (classical monocytes), CD14⁺CD16⁺ (intermediate monocytes), or CD14⁻CD16⁺ (non-classical monocytes). (B) Proportions of classical circulating monocytes in children (n = 17), younger adults (n = 7), and older adults (n = 8). (C) Gating strategy for flow cytometry analysis of BAL monocytes. (D) Total proportions of CMs in the BAL of children (n = 5), younger adults (n = 5), and older adults (n = 9).(E) Proportions of AMs in children (n = 6), younger adults (n = 5), and older adults (n = 8). Values shown are mean ± SEM. *, P < 0.05; **, P < 0.01; Mann–Whitney U test.