Autologous mesenchymal stem cells: clinical applications in amyotrophic lateral sclerosis

Our study was aimed to evaluate the feasibility and safety of intraspinal cord implantation of autologous mesenchymal stem cells (MSCs) in a few well-monitored amyotrophic lateral sclerosis (ALS) patients.

Seven patients affected by definite ALS were enrolled in the study and two patients were treated for compassionate use and monitored for at least 3 years. Bone marrow was collected from the posterior iliac crest according to the standard procedure and MSCs were expanded ex vivo according to Pittenger's protocol. The cells were suspended in 2 ml autologous cerebrospinal fluid and transplanted into the spinal cord by a micrometric pump injector.

The in vitro expanded MSCs did not show any bacterial o fungal contamination, hemopoietic cell contamination, chromosomic alterations and early cellular senescence. No patient manifested major adverse events such as respiratory failure or death. Minor adverse events were intercostal pain irradiation and leg sensory dysesthesia, both reversible after a mean period of 6 weeks. No modification of the spinal cord volume or other signs of abnormal cell proliferation were observed. A significant slowing down of the linear decline of the forced vital capacity was evident in four patients 36 months after MSCs transplantation.

Our results demonstrate that direct injection of autologous expanded MSCs into the spinal cord of ALS patients is safe, with no significant acute or late toxicity, and well tolerated. The clinical results seem to be encouraging.