When the lungs are attacked by a virus, the damage doesn't stop there. The body's natural defenses cause inflammation while fighting the virus, often leaving lasting problems. The cells that make up the lungs' mucosal lining are exposed to the environment with every breath - both highlighting the risk of infection and emphasizing the need for a robust response. In a paper published recently in Science,
When injuries or infections occur, the immune system mounts a protective response by releasing cells and proteins to affected tissues. This complex cascade is called inflammation. But as we age, inflammation gradually increases and becomes persistent instead of being a state that occurs only when things go wrong. Among the cells that that help to regulate this inflammageing are a variety of macrophages - white blood cells that hoover up pathogens and cellular debris - that reside in fat tissue.