Lung environment in healthy old age shapes the phenotype and CCR2-mediated recruitment of a subset of apoptotic, high-turnover alveolar macrophages

Alveolar macrophages (AMs) maintain lung homeostasis and health. The impact of inflammaging on resident and recruited AM populations requires further definition.

Herein, we examined the effect of age on the phenotype and ontogeny of AMs from humans, non-human primates and mice. We identify 3 AM subpopulations in old age, two of which are increased more than 10-fold with age. RNA-seq analysis identifies unique transcriptional profiles of the 3 AM subpopulations.