Figure 1. The morphology of porcine neural progenitor cells (NPCs) changes with time in culture and treatment condition. A: Phase contrast image of pNPCs just before the initiation of treatment. B-D: pNPCs maintained under standard proliferation conditions increased in number with time but did not change appreciably in morphology. E-G: pNPCs cultured under ciliary neurotrophic factor (CNTF) treatment conditions showed an increasing abundance of small cells with long, thin processes. H-J: pNPCs cultured under fetal bovine serum (FBS) treatment conditions resulted in larger cells with a greater tendency toward polygonal morphology. Scale bar: 100 µm.