FIG. 3.

Engrafted nasal MSCs migrate to the spiral ganglion region and promote an increase in spiral ganglion neurons. GM-lesioned cochleae in culture were either untreated (A) or treated with nasal MSCs [(B–D), red]. An analysis after 14 days shows that cultures which did not receive nasal MSCs have largely absent Tuj-1 neuronal staining in the spiral ganglion (A); in MSC-treated cultures, the nasal MSCs tend to cluster in the lesioned spiral ganglion [(B), arrows]; this is readily apparent on orthogonal views in (B), where the Deiter's cells and inner hair cells are identified in the sensorineural epithelia area, and the red labeled MSCs engraft in the spiral ganglion area. There are prominent Tuj-1-labeled neuronal processes extending from this region in MSC-treated cultures. Nuclei are counterstained with DAPI (blue); bar=50 μm in Z-stack views and 25 μm in orthogonal views. (C, D) A three-dimensional view from a boxed region in (B) (C) and a similar region from a different specimen (D) show how some neurons with Tuj-1 (+) processes (green) are labeled with Qdot beads (red), indicating that they are human nasal MSC derived; bar=5 μm; 40×oil immersion objective. (E) Eosin-stained histologic section through the cochlea, labeled to provide orientation for confocal figures. SGNs, spiral ganglion neurons; IHC, inner hair cell. Arrowheads indicate TuJ-1 (+) nasal MSC-derived cells. Color images available online at www.liebertpub.com/scd