Figure 21B. Microglial phagocytic assay in 3D culture

Representative confocal time-lapse images of microglia phagocytosis in 3D culture. Green = Cx3cr1-GFP microglia, blue = 2 um beads. To establish a microglial phagocytic assay in 3D culture, microglial cells were cultured with 2 µm polystyrene beads in Matrigel-collagen gel. The cell-matrix mixture was allowed to solidify at room temperature for 15 min and then at 37°C for 15 min. Confocal z-stack time-lapse images were obtained for a period of 24 h in 15 min intervals. In 3D culture, microglia phagocytosed beads through their ramified main branching processes and cell bodies (Figure 21B). In contrast, 2D microglia phagocytosed beads mainly with their amoeboid cell bodies (Figure21B).