[Age dependence of immunological methods for detecting an immunodeficiency state (author's transl)]

Cell-mediated and humoral immune responses were studied in 43 healthy volunteers aged between 15--77 years. Besides various skin tests with the antigens candida, trichophyton, mumps, streptokinase-streptodornase, tuberculin, DNCB and KLH also in vitro experiments measuring the immunoglobulin- and complement concentrations, the antibody production to KLH, the lymphocyte transformation rate to PHA, Pokeweed, Con A, PPD were done nearly in all patients. The responsiveness of lymphocytes to PHA and Con A and the sensitization of the skin with DNCB declines in the aged humans, beginning already at the 4th-5th decade. The skin tests with candida, trichophyton were not significantly different in the various age groups. The number of persons with positive skin reactions to the antigens mumps and streptokinase-streptodornase decreased also with advancing age. Lymphocyte transformation and skin test with PPD or tuberkulin were markedly increased beyond the age of 30. Serum levels of immunoglobulins, complement components, the antibody production to KLH, and the lymphocyte transformation rate to Pokeweed were not significantly different in the age groups. Correlation between the tests within each person could not be detected. We made the experience that only a few tests are not enough for the evaluation of an immunodeficient state, but that several tests, a so called TEST BATtery", are necessary.