MRC1 and chronic obstructive pulmonary disease: A study conducted scRNAseq on BALF samples from healthy non-smokers and COPD patients, reveals the presence of four distinct macrophage sub-populations in COPD 81, and the classification of CD206+ macrophages based on their autofluorescence levels was achieved by integrating flow cytometry and bulk RNA sequencing (bulk-seq) methodologies, resulting in the identification of CD206+ autofluorescenthigh AMs (tissue resident-derived) and CD206+ autofluorescentlow AMs (monocyte origin) 81.