AGER and chronic obstructive pulmonary disease: Flow cytometry-based detection of macrophage polarization and neutrophil infiltration in mouse lung tissue further confirmed that both macrophage M1 polarization (Fig. 2R–T, Additional file 1: Fig. S1Q) and subsequent neutrophil infiltration (Fig. 2U, V, Additional file 1: Fig. S1R) were significantly inhibited in COPD mice with RAGE KD following treatment with CS.