Effects of Chase ABC on NPC morphology blocked by Echistatin (Ech). (A) A phase-contrast photomicrograph shows that floating neurospheres were formed from dissociated NPCs when cultured for 24 hours in the growth medium containing EGF and bFGF. (B) Application of Ech alone did not affect the morphology of neurospheres. (C) Exposure to Chase ABC induced neurospheres to attach to the bottom of the well and migration of cells outward. (D) Ech administration blocked the effects of Chase ABC in that NPCs maintained their inherit growth properties. Scale bar: 200 μm. (E) Quantitative data demonstrated that Chase ABC treatment resulted in a significant increase in the percentage of attached neurospheres, which could be blocked by the administration of Ech. Data were shown as mean ± SEM of four independent experiments with at least 350 neurospheres examined in each group. ** P < 0.01.