Gut & MicrobiomeHow Aging T Cells Destroy Your Gut Barrier and Fuel Chronic Inflammation
Most people know the gut lining weakens with age, but this review highlights an overlooked culprit: the immune T cells living inside the intestinal wall. The gut houses the body's largest T cell population, and these cells directly regulate how well the gut barrier holds together. As we age, specific T cell subsets — including Th17, Th22, regulatory T cells, and gamma-delta T cells — shift in composition and become dysfunctional, some turning senescent or exhausted. These changes disrupt the signals that maintain tight junctions, mucus layers, and antimicrobial defenses. The result is increased leakiness, microbial translocation into the bloodstream, and the smoldering systemic inflammation known as inflammaging. Insights from HIV infection and inflammatory bowel disease provide a window into how accelerated T cell aging mimics what happens more slowly in healthy older adults.
