concanavalin-a and Magnesium-Deficiency

The ability of rats fed a magnesium-deficient diet to produce interleukins (ILs) and the effect of ILs on in vitro lymphocyte mitogenesis have been studied in rats. Lack of magnesium resulted in a lower number of plastic-adherent spleen cells and in a reduction of IL-1 production. IL-2 production was not significantly affected, indicating differential sensitivity of T cells to magnesium deficiency. The diminished mitogenic response of splenocytes to concanavalin A (Con-A) was restored by the addition of IL-1 supernatant, while the addition of IL-2 supernatant and recombinant IL-2 resulted in significantly greater enhancement of proliferation in response to Con-A, compared with that of control spleen cells. The fact that recombinant IL-2 restored the T-cell responses to Con-A indicates that the active factor in the IL-2 supernatant is IL-2.

Topics: Animals; Concanavalin A; Interleukin-1; Interleukin-2; Lipopolysaccharides; Lymphocyte Activation; Macrophages; Magnesium Deficiency; Rats; Rats, Inbred F344; Spleen; T-Lymphocytes

Plant lectin-induced proliferation of lymphocytes in vitro in both whole-spleen cell and T cell-enriched cultures was markedly effected by depletion of media copper, magnesium or zinc. The T lymphocyte-oriented mitogens concanavalin A and phytohemagglutinin and the B lymphocyte-oriented mitogen lipopolysaccharide were used to study variations in [3H]thymidine incorporation in lymphocytes cultured in media deficient in one mineral element. Since the stimulatory action of these mitogens also relates to the interaction of lymphocytes with accessory cells, we looked at the phagocytic ability of accessory cells cultured in the depleted media. In addition, we determined the variations in cell surface markers for B lymphocytes (Ia), T lymphocytes (Thy 1.2, Lyt 1 and Lyt 2) and accessory cells (Ia). Media depleted of copper, magnesium or zinc did not support normal T-lymphocyte proliferation but did support normal B-lymphocyte proliferation. The phagocytic ability of magnesium-deficient and zinc-deficient accessory cells was also depressed. This was related to depressed Ia expressions in the magnesium-deficient and zinc-deficient whole-spleen cell cultures. Total T-lymphocyte numbers, as well as Lyt 1+ cell percentages, were unchanged by media depletion, whereas Lyt 2+ cell percentages were depressed in both copper-deficient and magnesium-deficient splenocyte cultures.

Topics: Animals; Antigens, Surface; B-Lymphocytes; Cell Division; Concanavalin A; Copper; Culture Media; In Vitro Techniques; Lipopolysaccharides; Magnesium Deficiency; Mice; Mice, Inbred C57BL; Phagocytosis; Phytohemagglutinins; Spleen; T-Lymphocytes; Thymidine; Zinc