[Age- and sex-dependent changes in human T-lymphocyte subpopulations]

Changes in the expression of T-lymphocyte membrane antigens are seen in many diseases, particularly in autoimmune diseases. The reliability of these parameters, as well as their changes associated with age and sex, were examined in 232 healthy subjects using monoclonal antibodies of the OKT series. The precision of the indirect immunofluorescence method for determining the T3, T4 and T8 antigens (corresponding antibodies OKT 3, OKT 4, OKT 8) is within a range expected for biological testing methods (median variation coefficients 7-20%). In both sexes a statistically significant reduction of the T3+ cells (P = 0.0001; T-lymphocytes) and of the T8+ cells (P = 0.0004; T-suppressor lymphocytes) was seen with increasing age. In women (n = 115) the rate of T3+ and T4+ cells was 2-5% higher on the average (the T4+ cell population contains T-helper lymphocytes). According to these findings there is a statistically significant increase of the T4+ to T8+ cell ratio (P = 0.0001); due to the greater number of helper cells, the average T4/T8 quotients are greater in women than in men (P = 0.0076). The changes in the ratio of T-helper to T-suppressor cells are discussed as predisposing factors in the genesis of autoimmune diseases.