Genetic engineering neural stem cell modified by lentivirus for repair of spinal cord injury in rats.

OBJECTIVE: To explore the feasibility for therapy of spinal cord injury (SCI) by genetic engineering neural stem cell (NSC) modified by lentiviral vector. METHODS: Following the construction of the genetic engineering NSC modified by lentivirus to secrete both neurotrophic factor-3 (NT-3) and green fluorescence protein (GFP), hemisection of spinal cord at the level of T10 was performed in 56 adult Wistar rats that were randomly divided into 4 groups (n = 14), namely 3 therapeutic groups and 1 control group. The therapeutic groups were dealed with NSC, genetic engineering NSC, and concentrated lentiviral supernatant which carries both GFP and NT-3, respectively. Then used fluorescence microscope to detect the transgenic expression in vitro and in vivo, migration of the grafted cells in vivo, and used the Basso, Beattie, and Bresnahan (BBB) open-field locomotor test to assess the recovery of function. RESULTS: The transplanted cells could survive for long time in vivo and migrate for long distance. The stable transgenic expression could be detected in vivo. The hindlimb function of the injured rats in 3 therapeutic groups, especially those dealed with genetic engineering NSC, improved obviously. CONCLUSION: It is feasible to combine NSC with lentivirus for the repair of SCI. NSC modified by lentivirus to deliver NT-3, acting as a source of neurotrophic factors and function cell in vivo, has the potential to participate in spinal cord repair.

Repair and reconstruction of severe leg injuries: retrospective review of eighty-five patients.

OBJECTIVE: To explore a good way of the reconstruction of severe tibial shaft fractures by using different flaps and external fixators. METHODS: Eighty-five patients of Type IIIC tibial shaft fractures with average age of 42.5 years were treated in our hospital from 1990 to 2005. Injuries were caused by motorcycle accidents in 66 patients, by machine accidents in 16 patients, and by stone bruise in 3 patients. The management procedures consisted of administration of antibiotics, serial debridment, bone grafting if needed, application of different flaps, such as free thoracoumbilical flaps, fasciocutaneous flaps, saphenous neurocutaneous vascular flaps, sural neurocutaneous vascular flaps and gastrocnemius muscular flaps, and different external fixations, for instance, half-ring fixators, unilateral axial dynamic fixators, AO fixators, Weifang fixators, and Hybrid fixators. The average follow up was 6.3 years. RESULTS: All flaps survived. Eighty-three cases had bone healed. The average bone healing time of different external fixations was 5.5 months in 47 cases with half-ring fixators, 9.2 months in 4 cases treated with unilateral axial dynamic fixators, 8.5 months in 6 cases with AO fixators, 10.7 months in 16 cases with Weifang fixators, and 7.8 months in 10 cases with assembly fixators. Except half-ring fixation, other fixations all needed necessary bone graft. Two cases treated with unilateral axial dynamic fixators had nonunion of bone and developed osteomyelitis. The wounds healed after the removal of the fixators and immobilization by plaster. The last follow up examination showed ankle and knee motion was normal and no pain was noted. CONCLUSIONS: The combination of half-ring external fixators with various flaps provides good results for Type IIIC tibial shaft fractures.

The experimental study of genetic engineering human neural stem cells mediated by lentivirus to express multigene.

OBJECTIVE: To explore the feasibility to construct genetic engineering human neural stem cells (hNSCs) mediated by lentivirus to express multigene in order to provide a graft source for further studies of spinal cord injury (SCI). METHODS: Human neural stem cells from the brain cortex of human abortus were isolated and cultured, then gene was modified by lentivirus to express both green fluorescence protein (GFP) and rat neurotrophin-3 (NT-3); the transgenic expression was detected by the methods of fluorescence microscope, dorsal root ganglion of fetal rats and slot blot. RESULTS: Genetic engineering hNSCs were successfully constructed. All of the genetic engineering hNSCs which expressed bright green fluorescence were observed under the fluorescence microscope. The conditioned medium of transgenic hNSCs could induce neurite flourishing outgrowth from dorsal root ganglion (DRG). The genetic engineering hNSCs expressed high level NT-3 which could be detected by using slot blot. CONCLUSIONS: Genetic engineering hNSCs mediated by lentivirus can be constructed to express multigene successfully.