Early Migration of Sacral Neural Crest Cells in Mouse Embryos

Background: Neural crest cells (NCCs) are a group of multipotent embryonic cells which originate from the neural tube (developing central nervous system) and are capable of migrating to different locations within the embryo to form a variety of derivatives. In the avian, NCCs in the sacral region (sacral NCCs) have been shown to be able to give rise to neurons and glia of the hindgut. By using quail-chick chimeras, the complete migratory pathway of sacral NCCs from their origin to their final locations in the hindgut has been mapped. However, in mammals, information on sacral NCC migration is still scarce. Aims: In the present study, we used in situ cell labeling with wheat germ agglutinin gold conjugates or DiI as cell markers, whole embryo culture and histochemical staining to determine the early spatiotemporal migration of sacral NCCs in normal mouse embryos. Results and Conclusions: It was found that most of the sacral NCCs at the neuraxis caudal to the 24th somite (postumbilical level) started migration from the dorsal part of the neural tube at E9.5 and then migrated dorsoventrally in the pelvic mesenchyme between the neural tube and the somite. Many of the sacral NCCs resided in the region of the dorsal root ganglia on each side of the neural tube, while some of them continued to migrate dorsoventrally to reach the region around the dorsal aorta by E11.0. Hence, sacral NCCs enter the hindgut well after E11.0. Further studies will be carried out to find out the entire migratory pathway of sacral NCCs in the mouse prior to their entry to the hindgut.