Intracerebral Grafting of Genetically Modified Cells

The rationale for implanting cells to the brain is either for potential clinical application or to understand basic principals of brain function. The expectation of how an implanted cell would function differs for each experimental paradigm, and in many cases the mechanism of action is unknown. Among the possible mechanisms of action for implanted cells are: 1) to deliver trophic or tropic molecules; 2) to provide for secretion of neurotransmitters or hormones; 3) to release synaptically mediated neurotransmitters, and 4) to act as a bridge for regenerating axons to grow from the proximal side of a lesion to the distal side.