Immune function during ageing in man: relation between serological abnormalities and cellular immune status

In a group of 176 apparently healthy aged people living at home (age range 62-86 years) the prevalences of monoclonal immunoglobulin and of autoantibodies did not differ from those found in other studies, but remarkably 38% of the people studied had cold lymphocytotoxic antibodies. The occurrence of serological abnormalities showed no age dependency. The participants were grouped according to serological abnormalities. The various groups showed no differences in peripheral blood mononuclear cell composition (concentration of B lymphocytes and T lymphocytes or of T lymphocyte subsets with OKT 4 and OKT 8 phenotype) or function (lymphocyte stimulation with phytohaemagglutinin, concanavalin A, pokeweed mitogen and antigen cocktail). Compared with a control group of young blood donors, the lymphocyte stimulation responses tended to be lower in the old age groups. It is concluded that, as measured in this study, humoral abnormalities during ageing are not associated with changes in B and T lymphocyte subsets or function.