FIGURE 7.

The effect of CSF on phagocytosis of YG beads and apoptotic neuronal cells by human monocyte/macrophages. a, a typical YG beads uptake curve shows phagocytosis of beads by human monocytes is inhibited by 5% serum but not by 10% CSF. b, composite results for YG bead uptake at 5 min from 15 CSF samples and >40 human serum samples (*, p < 0.001). c, shown is phagocytosis of apoptotic SH-SY5Y neuroblastoma cells by human monocyte-derived macrophages. SH-SY5Y cells were induced to apoptosis by 0.2 μm staurosporine for 30 min and labeled with 10 μm CFSE. Before the addition of SH-SY5Y cells, BODIPY 630/650-SE (5 μm)-labeled human macrophages were incubated with 10% CSF or 10% serum glycoprotein-rich fraction or 20 μm CytD. Mixed cells were incubated for 3 h before collection and fixation. Results are representative of eight experiments with different CSF samples. d, phagocytosis of YG beads by human monocytes is shown. Cells were resuspended in sodium medium containing 50% mixed human CSF with or without 200 μg/ml CP, 200 μg/ml APP695α, or 5% serum before the addition of YG beads.