immunology allergic disorders
Overview of the Immune System
Geriatrics Essentials
With aging, the immune system becomes less effective in the following ways: The immune system becomes less able to distinguish self from nonself, making the development of autoantibodies and autoimmune disorders more common. Macrophages destroy bacteria, cancer cells, and other antigens more slowly, possibly contributing to the increased incidence of cancer among older adults. T cells respond less quickly to antigens. There are fewer lymphocytes that can respond to new antigens. The aging body produces less complement in response to bacterial infections. Although overall antibody concentration does not decline significantly, the binding affinity of antibody to antigen is decreased, possibly contributing to the increased incidence of Overview of Pneumonia , 