Trace metals, surface receptors and growth of human normal and leukemic lymphocytes

To evaluate the modulatory effects of trace metals on lymphocyte growth and maturation, thymidine uptake (TU), protein, ATP, Fe, Cu, Zn, ferritin, CD3, CD4, CD8 antigens, surface transferrin receptors (TFR) and interleukin 2 receptors (IL2R) were assessed in normal and T cell leukemia human lymphocytes, cultured in media with varying Fe, Cu and Zn concentrations [Me]. In normal lymphocytes in media with optimal [Me], all values increased significantly after PHA stimulation, except for intracellular metal concentration and CD3+, CD4+, CD8+ cells which were unchanged. In media with low or high [Me], all parameters except for CD8+ cells were decreased. In unstimulated ALL lymphocytes grown in media with optimal [Me], TU, protein, ATP, CD4+, Fe, Cu and ferritin were higher and Zn and CD8+ lower than in unstimulated normal cells: they did not change after PHA stimulation, except in media with low [Me], in which they approached the values of stimulated normal lymphocytes. TFR and IL2R for ALL cells were high in all media: IL2R but not TFR increased after PHA stimulation. No relationship between IL2R and TFR was demonstrable in any media. We conclude that the response of normal lymphocytes to stimuli is sensitive to variation in trace metals, whereas this response, absent in ALL lymphocytes, reappears only in media with low [Me] and is independent from TFR.