Case Report: Autologous bone marrow mononuclear cell transplantation improved motor function in a patient with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron loss, and no established treatment restores impaired motor function. In mouse models of ALS, bone marrow mononuclear cell (BM-MNC) injection improved motor function. In patients with ALS, direct spinal cord injection of BM-MNCs has also been reported to improve motor function. Here, we report the case of a 52-year-old male patient with ALS who underwent intravenous autologous BM-MNC transplantation and demonstrated improved motor function. His revised ALS Functional Rating Scale score increased from 17 before treatment to 18 at 24 weeks after transplantation. The score of Manual Muscle Testing of fifth finger metacarpophalangeal joint flexion improved from 0 before treatment to 2(-) at 24 weeks after transplantation. No serious adverse events were observed. As this is a single case report, additional case series and subsequent randomized clinical trials are essential to clarify the effect of BM-MNC transplantation on ALS outcomes. This case suggests, however, that motor dysfunction in patients with ALS might be reversible. These findings encourage future studies investigating motor function improvement, rather than disease progression slowing, by elucidating the mechanisms underlying BM-MNC transplantation and optimizing treatment.