Neural progenitor cells differentiated from embryonic and degenerated stem cells are regenerated into neurons and neural ridge cells. Transplantation of pre-regenerated neural progenitor cells into injured spinal cord and brain tissue results in the formation of mesodermal tumors in the tissues. By use of a protein called PSA-NCAM, neural progenitor cells can be separated into two groups of cells. Of these, PSA-NCAM-positive cells are neural cells that regenerate into neural tissue, and PSA-NCAM-negative cells are neural ridge cells that differentiate into mesodermal tissue. Only the PSA-NCAM-positive cells from the isolated neural progenitor cells can induce regeneration of the nerve tissue when transplanted into the injured spinal cord and brain tissue.
– Pure isolation of PSA-NCAM positive neuronal progenitor cells
PSA-NCAM marker is used to purely isolate positive cells from the separated cells.
– Isolation of neuronal progenitor cells using PSA-NCAM marker
Separation possible using PSA-NCAM marker
– Implant of isolated neural progenitor cells
When PSA-NCAM markers were used to separate positive and negative marker cells, and were implanted, it was confirmed that mesodermal tumors were formed only with the negative marker cells.
Experiment on embryonic stem cells – Spinal injury
– Improvement of motor function in spinal cord injury model
To demonstrate the efficacy of cell-mediated therapy in patients with spinal cord injury (SCI), we performed an animal model of spinal cord injury. After transplanting PSA-NCAM positive neural progenitor cells , we performed behavior assessments (Basso, Beatie, Bresnahan, BBB)
weekly for up to 10 weeks to detect changes in performance.
-The cell transplant group showed improvement in motor function (increased BBB score) compared to the control group. After 4 weeks the transplant group showed statistically significant improvements compared to the control group.
Cells were transplanted into the spinal cord injury model and after 10 weeks spinal tissue was examined. In order to confirm the anti-inflammatory effect of the cell transplantation, microglia in the spinal cord and activated microglia, which display antibodies Iba1 and ED1 in response to inflammation inflammation, were double-stained and analyzed for the proportion of activated microglia remaining in the tissue.
In the tissue grafted with cells, it showed a statistically significant decrease in activated microglia was compared with control group, indicating that cell grafting has an effect of reducing inflammation.
Confirming blood vessel function by immunohistochemistry (IHC) using smooth muscle actin (SMA) antibodies as an indicator.
In contrast to the control group in which media was used, more blood vessels were observed in the tissue of the transplanted group with statistically significant results.
3) Cell proliferation in the spinal cord
One week after producing the spinal cord injury model, cells were transplanted. BrdU was injected daily for one week, and spinal cord tissue was removed on the eighth day to compare the number of BrdU + cells in the control and cell transplanted groups.
We observed a statistically significant increase in new cells in the transplanted tissue compared to the control, and demonstrated that cell grafting increases endogenous cell proliferation in spinal cord injured animal models.