Aging of the immune system and susceptibility of the elderly to infectious diseases

Élodie Crétel-Durand is a doctor, gerontologist and immunologist. Too few researchers in France are interested in the ageing of the immune system, despite the considerable need for such research in view of the inevitable ageing of the population worldwide - even in developing countries - the increasing sensitivity of the elderly to infections, and their reduced response to vaccines. Current research shows that the process of immune system senescence occurs at all levels, but with a clear time lag between individuals of the same age. The body's barriers are breaking down, and B and T cells are undergoing a process of senescence amplified by the reduction in co-activation signals. In addition, the role of herpes viruses such as CMV, which infect us latently from an early age, seems to play a deleterious role here by mobilizing the residual population of naive T cells, which are no longer available to recognize new exogenous microbial or vaccine antigens.