척수손상백서에서 인간 제대혈 줄기세포이식이 신경기능회복에 미치는 영향

초록

Object: Recovery from central nervous system damage in adult mammals is impeded by their limited ability to replace lost cells and damaged myelin, and reestablish functional neural connections. However, recent advances in stem cell biology are making it possible to induce the regeneration of injured axons after spinal cord injury (SCI). Cord blood derived stem cells are known to be differentiated into mature neuron and glial cells in vitro and in vivo. Theses findings suggest cord blood derived stem cells could be used for the potential therapeutic donor cells in treating various central nervous system diseases including SCI. Methods: To better direct repair following SCI, we transplanted human umbilical cord blood cells into an adult rat contusion model of SCI promoted long-term improvement in function relative to a lesion-control group. Human umbilical cord blood cells were obtained from normal full term placenta. Cells were cultured in vitro for 7days. Bromodeoxyuridine(BrdU) was added to the medium for identifying cells derived from cord blood. Cultured cord blood cells (2X 106 cells) were injected into the injury epicenter 7 days after SCI which was subjected weight-drop impact by using NYU impactor. The Basso-Beattie-Bresnahan (BBB) locomotor rating scores were used to evaluate the functional improvement of cord blood transplanted rats. Immunohistochemistry was followed to exam neuronal and glial diffenrentiation of transplanted cord blood cells. Results:Immunohistochemical analysis 7 weeks after contusion injury showedmitotic gliogenesis occurred from transplanted donor cord blood cells within the adult rat spinal cord. These donor-derived astrocytes like cells extended their process into the host tissues. GFAP-positive astrocytes and nestin-positive cells derived donor cells were detected. Conclusion:in vitro expanded cord blood cells are a potential source for transplantable material for treatment of SCI.