Figure 2. Induction of apoptotic cell death in mouse macrophages by HEMA. (A) Mouse macrophage cell line RAW 264.7 cells were left untreated or treated with different concentrations of HEMA (as indicated in the Fig.) in an overnight assay, and the levels of DNA fragmentation were determined by PI staining after ethanol fixation of the cells. (A) represents the proportion of the macrophage population at G₀/G₁ cell cycle, (B) represents the S phase, (C) represents the G₂/M phase, and (D) represents the sub-G₀/G₁ peak or fragmented proportion of the cells indicating apoptotic cell death. (B) Mouse macrophage cell line RAW 264.7 cells were left untreated or treated with two different concentrations of HEMA. The levels of apoptotic cell death were determined after an overnight incubation in RAW 264.7 cells dually staining with PI and annexin V. The numbers in each quadrant represent the percentages of cells positive for that quadrant. Ten thousand events were analyzed for each sample.