LPS induces apoptosis in bone marrow macrophages.
(A and B) 106 macrophages were stimulated with 100 ng/mL of LPS for 6 hours. DNA was stained with DAPI, and induction of apoptosis was analyzed by cytometric analysis (A) or visualizing the cells in a fluorescence microscope (B). Apoptotic cells are marked with arrows. (C and D) LPS induces apoptosis in a time-dependent manner. Apoptotic DNA from macrophages treated with LPS (100 ng/mL) for the indicated times was analyzed by agarose gel electrophoresis (C) or by using an ELISA technique (D). (E) LPS induces apoptosis in a dose-dependent fashion; 105 macrophages were treated for 12 hours with the indicated concentrations of LPS. Apoptotic DNA was measured as in (D). (F) Apoptosis induced by LPS depends on the presence of FBS. The cells were treated with 100 ng/mL LPS for 12 hours in the presence of the indicated concentrations of FBS. Fragmentation of DNA was measured by ELISA. The ELISA experiments were performed in triplicate and represented as the mean value ± SD. These figures are representative of 4 independent experiments.
