Aging Lung Environment Reshapes Macrophage Populations Across Species
Published in Biology, Immunology, Journals.
Publication date: October 8, 2026. Research publication: October 7, 2026.
A Nature Communications study examines how healthy aging changes alveolar macrophages, immune cells that help maintain the lungs. Researchers studied mice, non-human primates and humans, identifying three macrophage subpopulations in older individuals.
One population, marked by CD11c and CD11b, increased more than tenfold across the mammalian species examined. RNA sequencing distinguished the populations’ gene-expression profiles and linked aging-associated changes with inflammation and immune dysregulation.
Experiments in mice showed that the local alveolar environment can reprogram resident macrophages toward this phenotype. It also promoted CCR2-dependent recruitment of monocyte-derived macrophages, which were relatively short-lived and underwent rapid turnover through Fas-mediated cell death.
The findings help explain how the aging lung environment shapes immune-cell behavior. They do not demonstrate a treatment that reverses aging, improves lifespan or prevents respiratory disease in people. Mechanistic experiments in mice should be distinguished from the cross-species observations.
Source: Pahari and colleagues, Nature Communications, October 7, 2026. DOI: 10.1038/s41467-026-78156-x.