A new study shows for the first time how chronic inflammation due to long-term infections or autoimmune conditions such as rheumatoid arthritis, ulcerative colitis, or Crohn’s disease dampens the body’s immune response as we age. The study elucidates the role of DNMT3A in modulating immune responses during chronic infection or stress and also explains how aging and inflammation are linked to blood cancers, stroke, and cardiovascular disorders.