Fig. 1
Donor GFP-labeled stem cells create chimeric spiral ganglion and vestibular neurons in the Neurog1 heterozygote. a Schematic of experimental methods for BC. Neurog1+/− female mice were superoverulated with hormones. Zygotes were extracted and fertilized by in vitro fertilization (IVF) with Neurog1+/− male sperm and allowed to mature until blastocyst stage (~E3.5), at which point all blastocysts were injected with GFP-labeled iPSCs. Complemented blastocysts were transferred to a pseudopregnant surrogate. Pregnancies were to taken to birth, embryos were harvested, and complementation in the inner ear was assessed. b Diagram of the inner ear indicates the vestibular (balance) portion and cochlear (auditory) portion. Low magnification of the midmodiolar region of the cochlea in c representative image of the Neurog1+/+ wild type inner ear shows the absence of GFP-labeled stem cells in the SGN (arrows) (images are from a single Neurog1+/+ wild type (1/2), sample number 111807) in contrast to d specific stem cell complementation in the SGN in a Neurog1+/− heterozygote (arrowheads) (images are from a single complemented Neurog1+/− heterozygote (1/3), sample number 111802). High-magnification images of the basal cochlear turn show e the presence of GFP-labeled stem cells in a Neurog1+/− heterozygote SGN (arrowhead) and absence in f the Neurog1+/+ wild type SGN (arrow). Specific stem cell complementation was seen in the vestibule of a Neurog1+/− heterozygote, g in Scarpa’s ganglion adjacent to the utricle (UT) and saccule (Sac), h neurites (arrowhead) innervating the posterior ampulla, and i neurites innervating the anterior and lateral ampullae (arrowheads). AA anterior ampulla, LA lateral ampulla, PA posterior ampulla, Ut utricle, SAC saccule, RC Rosenthal’s canal with SGNs. All scale bars are 100 μm. Scale bar in d also corresponds to c