Xenotransplantation of Human Umbilical Mesenchymal Stromal Cells Derived from Wharton's Jelly Mitigates Mouse Amyotrophic Lateral Sclerosis.

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by progressive degeneration of motor neurons in the cerebral cortex, brainstem, and spinal cord, eventually leading to paralysis, respiratory failure, and death. Currently, no effective treatment exists for ALS.

METHODS

This study examined the therapeutic potential of human umbilical cord mesenchymal stromal cells (HUMSCs) by transplanting 2 × 10⁶ HUMSCs into the spinal canal of transgenic mice expressing mutant human superoxide dismutase 1 (SOD1) at 8 weeks of age.

RESULTS

Survival analysis showed that the SOD1 group lived up to 171 days, while the SOD1 + HUMSCs group survived up to 199 days, extending lifespan by 17 days on average. Motor function tests, including rotarod performance, grip strength, open field activity, and balance beam tests, demonstrated that while the SOD1 group experienced progressive decline, the SOD1 + HUMSCs group showed improvement. Electrophysiological assessments at 20 weeks of age revealed weak muscle action potential in the SOD1 group, whereas the SOD1 + HUMSCs group exhibited noticeable improvements. Histological analysis indicated significant spinal cord atrophy in the SOD1 group, while HUMSCs transplantation mitigated this degeneration. Moreover, HUMSCs reduced blood-spinal cord barrier leakage and T lymphocyte infiltration, alleviating inflammation. The number and size of activated microglia and astrocytes increased in the SOD1 group but were reduced with HUMSCs treatment. Additionally, HUMSCs preserved more motor neurons in the anterior horns.

CONCLUSION

Collectively, transplantation of HUMSCs effectively reduced inflammatory reaction in spinal cord, decreased loss of neurons, ameliorated disease deterioration, and extended life span, suggesting that it could serve as a new direction of ALS treatment to improve patients' quality of life or behavioral function.