The immune system through the ages

<abstract> <p>The components of the immune system develop in utero and like a computer, some components are immediately functional (the innate components) but other components must learn the programs and details necessary to function (antigen adaptive components). Like other systems, including military and municipal, the innate and antigen specific components develop into an immune system that helps maintain and surveil the other body processes and systems for aberrations, provide surveillance and protection of the mucoepithelial borders and protection from microbial invasion. Inability, excesses, or errors in these processes cause disease. Aging of the immune system brings immunosenescence, inflammaging, more errors, and decreased surveillance which increases risk for new infections (e.g. COVID-19, influenza), recurrence of latent infections, cancer and autoimmune and inflammatory diseases. With greater understanding of the surveillance, effector and regulatory deficits upon aging, better therapies can be developed.</p> </abstract>