Abstract: Objective Establishing and verifying a method for labeling neural progenitor cells (NPCs) with carboxyl fluorescein diacetate succinimidyl ester (CFSE) fluorescent probe. Methods CFSE was injected into the lateral ventricle of embryonic mice to label ventricular zone (VZ) cells. The tissue was collected at 1 and 3 hours after injection to detect its specificity by immunofluorescence. Dorsal neocortex was separated at 1 hour after injection, the strong positive cells were sorted by fluorescence activated cell sorting (FACS) and the cell identity was verified by stem cell markers and neuronal markers. Results CFSE instantaneously labelled (pulse labeling) cells in the ventricular zone, and the labeling window was between 3 and 6 hours. Signal of CFSE when performing long-term labeling would be attenuated. Seventy percent of the cells sorted by CFSE were neural precursor cells, and a small portion of which were neurons. Conclusions CFSE can be used for pulse and long-term labeling in vivo. Also, CFSE can be applied for sorting NPCs, while the current sorting strategy needs to be adjusted to improve specificity.

Key words: carboxyfluorescein diacetate succinimidyl ester(CFSE), neural progenitor cells, fluorescence activated cell sorting(FACS)