Zinc induced apoptosis in bone marrow and splenic B-lineage lymphocytes of the mouse

Abstract

Recently, our lab discovered that moderate concentrations of zinc could induce apoptosis in CD4 +CD8 +TCR lo murine thymocytes. To determine if B-lineage lymphocytes demonstrated similar sensitivity, bone marrow and splenic B-lymphocytes were treated with zinc at a concentration range of 100 to 200 μM for 8 hrs and analyzed by flow cytometry for apoptotic death in the B220 +IgM − and B220 +IgM + subsets of the bone marrow and the IgM + and IgG + subsets of the spleen. B220 +IgM + B-lineage cells in the bone marrow and IgM + B-cells in the spleen were found to be most susceptible exhibiting 38% and 25% levels of zinc-induced apoptosis. B220 +IgM − bone marrow B-lineage cells and IgG + B-cells in the spleen were found to be less sensitive to zinc treatment than IgM-bearing cells. Thus, it is possible that zinc might initiate apoptosis in some cells of the immune system due to fluxes of the metal in cells or the presence of intracellular pools of zinc.