Key points from article :
Japanese researchers have made a significant breakthrough in spinal cord injury treatment using reprogrammed stem cells. In a pioneering clinical trial, a paralysed man can now stand on his own after receiving an injection of neural stem cells derived from induced pluripotent stem (iPS) cells. Another participant has regained movement in his arms and legs, though two others showed no significant improvement. The study, led by Hideyuki Okano at Keio University in Tokyo, marks an important step in regenerative medicine, though the results have yet to be peer-reviewed.
iPS cells are created by reverting adult cells to an embryonic-like state, allowing them to develop into different cell types. In this trial, neural precursor cells derived from donor iPS cells were injected into the injury sites of four men. The surgeries took place between 2021 and 2023, with patients receiving immunosuppressants to prevent rejection. At a one-year follow-up, no severe side effects were observed. One patient improved to a classification of C on the American Spinal Injury Association Impairment Scale (AIS), while another reached level D and is now training to walk—considered a dramatic recovery.
While the findings are promising, scientists caution that larger trials are needed to confirm efficacy. Some individuals with spinal cord injuries experience natural recovery, so it remains uncertain whether the improvements resulted from the treatment. Previous studies suggest transplanted iPS cells may support neural regeneration by secreting beneficial substances and rebuilding damaged tissue. However, a major challenge is ensuring cell survival post-transplantation. Okano and his team observed signs that some transplanted cells did persist, offering hope for future research. His startup, K Pharma, now plans to seek approval for larger clinical trials to further investigate this potential breakthrough.
