Transcription regulators differentiate mesenchymal stem cells into chondroprogenitors, and their in vivo implantation regenerated the intervertebral disc degeneration

Figure 9 Histological examination of intervertebral disc. A: (A-G) Bright field imaging of intervertebral discs (IVDs) showing nucleus pulposus (NP) content of the healthy (Co6/7), and degenerated disc (Co5/6) treated with normal mesenchymal stem cells (MSCs), transfected MSCs, and induced chondro-progenitor cells (iCPCs) (Co5/6) IVDs, in each group. Bright-field microscopic images of IVDs were captured from the cryosections stained by hematoxylin and eosin; normal healthy disc, degenerated disc, and degenerated disc transplanted with normal MSCs, Six-1 transfected MSCs, Sox-9 transfected MSCs, iCPCs, and Sox-9 + Six-1 transfected MSCs, respectively; B: (A-G) Bright-field microscopic images of IVDs were captured from the cryosections stained by Alcian blue displayed glycoproteins secreted by the transplanted cells compared to the degenerated disc; normal healthy disc, degenerated disc, and degenerated disc transplanted with normal MSCs, Six-1 transfected MSCs, Sox-9 transfected MSCs, iCPCs, and Sox-9 + Six-1 transfected MSCs, respectively; C: Histological grading with a score for regeneration. AF: Annular fibrosus.