Figure 4.

CXCR7 mediates neural progenitor cell (NPC) migration in response to CXCL12 in vivo. (A–O): Qtracker-labeled Cxcr4^−/− NPCs (A–H) or same number of NPCs with CCX771 (100 μM in cell suspensions, (I–L) were transplanted into the left striatum of C57BL/6 mice through intracranial injection. Immediately after NPC transplant, parallel injection of saline (A–D) and CXCL12 (E–L) was performed at 1 mm apart from the NPC injection track. Seven days after injection, mice were killed and migrated NPCs were determined through immunohistochemistry. Scale bar =250 μm (A–L). (M): Migrated NPCs were quantified as the percentage of Qtracker fluorescence in the saline or CXCL12 track to the total Qtracker fluorescence. **, p <0.01, compared with the saline group; #, p <0.05, compared with the CXCL12 group. N =5 for each group. (N–O): Migrating NPCs in the copus colusm were visualized in high magnification pictures taken from the indicated area (arrow) in (G) and (H). Scale bar =20 μm (N–O). Abbreviations: DAPI, 4′,6-diamidino-2-phenylindole; GFAP, glial fibrillary acidic protein; NPCs, neural progenitor cell.