Neural Stem Cell Transplantation and Mechanisms for Functional Recovery

Neural stem cell transplantation has demonstrated its therapeutic potential in many neurological disorders. The long-thought prime mechanism of action was the replacement of cells lost to injury or neuro degeneration. Now, more and more evidence has provided insight into other bystander mechanisms through which these cell grafts could bring about a functional and structural restorative benefit. Their role in immunomodulation, neurogenesis and brain plasticity, as well as their capacity to secrete constitutively neuroprotective factors, open interesting doors to new frontiers in therapeutics that go beyond cell substitution. The purpose of this review is to outline the factors, both host and graft dependent, shown to mediate these new mechanisms of therapeutic action posterior to NSCs introduction into a pathological host environment.