Transplantation of autologous bone marrow stromal cells (BMSC) for ischemic stroke - strategy and tactics for clinical application

Objective: There is increasing evidence that the transplanted bone marrow stromal cells (BMSC) significantly promote functional recovery after central nervous system damage in the animal models of various kinds of CNS disorders, including cerebral infarct. However, there are several shortages of information when considering clinical application of BMSC transplantation for patients with neurological disorders. In this meeting, therefore, we discuss what we should clarify to establish cell transplantation therapy in clinical situation and describe our recent works for this purpose. Methods and Results: The BMSC have multiple abilities to differentiate into the neural cells and to promote neuronal survival and axon elongation, contributing to rebuild the neural circuits in the injured CNS. Using optical imaging and MRI techniques, the transplanted BMSC can non-invasively be tracked in the living animals for at least 8 weeks after transplantation. Clinical MR apparatus can visualize the tagged BMSC in the brain. FDG PET is quite valuable to monitor the recovery of brain metabolism after transplantation. The BMSC can be expanded using the animal protein-free culture medium within a clinically relevant period. G-CSF is useful to enhance their proliferation when the BMSC are obtained from the aged patients. There are optimal dose and timing of BMSC transplantation to yield significant therapeutic benefits. Conclusion: It is urgent issues to develop clinical imaging technique to track the transplanted cells in the CNS and evaluate the therapeutic significance of BMSC transplantation to establish it as a definite therapeutic strategy in clinical situation in very near future.