MSR1 and chronic obstructive pulmonary disease: Interestingly, we observed a remarkable percentage of cells expressing MSR1 that did not correspond to any of the cellular subpopulations analyzed in this study, especially in the NA and COPD groups, but we only found significant differences (p = 0.0268) between the NA (12.64 ± 16.32%) and AA (1.57± 3.96%) groups (Figure S2A).