Changes in immune function with age.

Aging is associated with a decline in immune function in humans and animals. The primary defects appear to reside in the T-cell compartment. Improving understanding of the mechanisms underlying the general decline in immune functions with age may enhance our ability to prevent and treat age-associated illnesses. Development of biomarker(s) of immune senescence may eventually help clinicians to identify subpopulations of the elderly who are at risk for infections, malignancies, and possibly autoimmune diseases.