Immunomodulatory effects of stem cells: Therapeutic option for neurodegenerative disorders.

Stem cells have the capability of self-renewal and can differentiate into different cell types that might be used in regenerative medicine. Neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), and amyotrophic lateral sclerosis (ALS) currently lack effective treatments. Although stem cell therapy is still on the way from bench to bedside, we consider that it might provide new hope for patients suffering with neurodegenerative diseases. In this article, we will give an overview of recent studies on the potential therapeutic use of mesenchymal stem cells (MSCs), neural stem cells (NSCs), embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and perinatal stem cells to neurodegenerative disorders and we will describe their immunomodulatory mechanisms of action in specific therapeutic modalities.