By IF, these cells were tryptase+ (hence, mast cells) and located around the airways; (2) By IF, c-Kitlow/CD45+/triptase- (0.07 ± 0.06 (NS), 0.03 ± 0.02 (S), and 0.06 ± 0.07 (COPD) cells/field), which likely correspond to innate lymphoid cells; (3) By FACS, c-Kitlow/CD45-/CD34+ (0.95 ± 0.84% (NS), 1.14 ± 0.94% (S) and 0.95 ± 1.38% (COPD)). This evidence concerns the gene CD34 and chronic obstructive pulmonary disease.