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

BACKGROUND

Intervertebral disc degeneration (IVDD) is the leading cause of lower back pain. Disc degeneration is characterized by reduced cellularity and decreased production of extracellular matrix (ECM). Mesenchymal stem cells (MSCs) have been envisioned as a promising treatment for degenerative illnesses. Cell-based therapy using ECM-producing chondrogenic derivatives of MSCs has the potential to restore the functionality of the intervertebral disc (IVD).

AIM

To investigate the potential of chondrogenic transcription factors to promote differentiation of human umbilical cord MSCs into chondrocytes, and to assess their therapeutic potential in IVD regeneration.

METHODS

MSCs were isolated and characterized morphologically and immunologically by the expression of specific markers. MSCs were then transfected with Sox-9 and Six-1 transcription factors to direct differentiation and were assessed for chondrogenic lineage based on the expression of specific markers. These differentiated MSCs were implanted in the rat model of IVDD. The regenerative potential of transplanted cells was investigated using histochemical and molecular analyses of IVDs.

RESULTS

Isolated cells showed fibroblast-like morphology and expressed CD105, CD90, CD73, CD29, and Vimentin but not CD45 antigens. Overexpression of Sox-9 and Six-1 greatly enhanced the gene expression of transforming growth factor beta-1 gene, BMP, Sox-9, Six-1, and Aggrecan, and protein expression of Sox-9 and Six-1. The implanted cells integrated, survived, and homed in the degenerated intervertebral disc. Histological grading showed that the transfected MSCs regenerated the IVD and restored normal architecture.

CONCLUSION

Genetically modified MSCs accelerate cartilage regeneration, providing a unique opportunity and impetus for stem cell-based therapeutic approach for degenerative disc diseases.

Key Words: Intervertebral disc degeneration, Human umbilical cord, Transcription factors, Mesenchymal stem cells, Gene expression, Regeneration

Core Tip: In this study, we highlighted that overexpression of chondrogenic transcription factors in human umbilical cord derived mesenchymal stem cells (hUC-MSCs) accelerated their differentiation into chondroprogenitor cells. The synergistic effect of Sox-9 and Six-1 transcription factors leads the MSCs to differentiate into chondrogenic cells in the basal medium, which produced the same effect as the chondro-induction medium. In vivo transplantation of these transfected cells leads to their homing, integration, and differentiation into nucleus pulposus cells of the intervertebral disc. This approach could help to develop a better treatment option for degenerative disc diseases.

• Citation: Khalid S, Ekram S, Salim A, Chaudhry GR, Khan I. Transcription regulators differentiate mesenchymal stem cells into chondroprogenitors, and their in vivo implantation regenerated the intervertebral disc degeneration. World J Stem Cells 2022; 14(2): 163-182
• URL: https://www.wjgnet.com/1948-0210/full/v14/i2/163.htm
• DOI: https://dx.doi.org/10.4252/wjsc.v14.i2.163