Figure 6

NPCs in a 10-month old adult wild type mouse cerebellum 30 days after grafting. (a) Integration of donor cells into the molecular layer of lobule VI (simplex). Donor cells grafted into the recipient cortex move along the pial surface. Some of them remained in the interlobular space between lobule simplex and crus 1. Other donor cells passed through the pia and integrated into the host molecular layer (inward route). (b and c) Donor GPF-positive cells matured in the Purkinje cell lineage. The bipolar morphology with the characteristic dendritic tree on the one side and the axonal process (indicated by arrows) on the opposite side indicate that the GFP-positive cells are Purkinje neurons. (b) Donor Purkinje cell with cell body grafted into the molecular layer shows a normal axon and dendritic tree, but an inverted orientation. (c) Grafted cell aligned to the host PNs exhibiting the correct orientation, but an axotomized axon. These transplanted PNs are representative of the successfully grafted donor cells. (d) GFP-positive-PNs co-expressed calbindin and parvalbumin. (e) GFP-positive NPCs grafted into an adult CDK9-mCherry mouse cerebellum showed that (f) only the resident PNs expressed CDK9 in their nucleus and soma. (g) GFP-positive donor cells expressed calbindin, but did not express CDK9-mCherry, indicating there is no fusion with resident cells. Arrowhead points to CDK9-mCherry expression inside and around nuclei of resident cells (n = 3 mice). (h) Quantification of calbindin-positive (n = 11 mice) and NeuN-positive (n = 16 mice) cells over a total actin-GFP-positive cells. All CDK9-mCherry micrographs were obtained from sagittal sections. (i) Percentage of calbindin-positive cells over a total number of actin-GFP-positive grafted cells plotted against the age of the host mouse cerebellum (n = 6 for four-month-old mice; n = 5 for ten-month-old mice). Chart shows the mean and SEM with statistical comparison assessed via one-way ANOVA followed by Tukey’s with statistical significance set at p ≤ 0.01. Scale bars: 500 μm (a); 20 μm (b, c, f and g); and 40 μm (d and e). ML: Molecular layer; PCL: Purkinje cell layer; GCL: Granule cell layer. *all micrographs represent coronal sections unless otherwise stated.