Figure 5

Apoptotic disc cells stimulating phagocytosis by other cells. A sequence of phase-contrast images obtained from video microscopy shows a THP-1 cell (white arrow) ingesting an apoptotic, phase-bright nucleus pulposus cell (black arrow). These frames demonstrate that apoptotic disc cells can trigger a phagocytic response. Images were taken over the course of 40 minutes. Original magnification × 100.