title: Lymphocyte proliferative response to PHA and anti-CD3/Ti monoclonal antibodies, T cell surface marker expression, and serum IL-2 receptor levels as biomarkers of age and health.
abstract: Alteration of T cell surface marker expression with a decrease of CD3 positive cells relative to the number of CD4 and CD8 positive cells, diminished in vitro proliferative response to mitogenic stimuli like PHA and antibodies to the CD3/Ti complex, and increase in serum IL-2 receptor levels, are among the changes in immunologic parameters that have been associated with advanced age. To distinguish between effects of the primary aging process and diseases of aging not known to be directly related to immune function, we investigated these variables in two well characterized populations of elderly donors (greater than 70 years) and a young adult control group (less than 35 years). The first group of older donors reported no evidence of significant chronic or recent acute illness and saw a physician only for routine medical care. The second group was randomly selected from individuals seen in a geriatric medicine clinic for diagnoses that included osteoarthritis and cardiopulmonary disorders. Altered surface marker expression and increased serum IL-2 receptor levels were seen only in the second group. On the other hand, lymphocyte proliferative responses to PHA, Leu 4 (anti-CD3) and a monoclonal antibody to the beta-chain of the T cell antigen receptor (WT31) were significantly decreased in both populations. Because we would expect primary aging to affect even extremely fit individuals of advanced age, we conclude that decrease in T cell proliferative response may represent a biomarker of primary aging in man. The alteration in surface marker expression and increased IL-2R levels in serum appear to be effects secondary to non-immunologic disease rather than aging.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55455.
authors.forename: H M
authors.initials: HM
authors.lastname: Hallgren
authors.forename: N
authors.initials: N
authors.lastname: Bergh
authors.forename: K J
authors.initials: KJ
authors.lastname: Rodysill
authors.forename: J J
authors.initials: JJ
authors.lastname: O'Leary
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D017252:CD3 Complex; D006262:Health; D006304:Health Status; D006801:Humans; D007376:Interleukin-2 / Q000097:blood; D008213:Lymphocyte Activation; D010835:Phytohemagglutinins; D011948:Receptors, Antigen, T-Cell / Q000032:analysis*; D011971:Receptors, Immunologic / Q000378:metabolism*; D015375:Receptors, Interleukin-2; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007376:Interleukin-2; D010835:Phytohemagglutinins; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2