Objective To investigate the feasibility of imaging of bone marrow mesenchymal stem cells (BMMSCs) labeled with superparamagnetic iron oxide(SPIO) transplanted into coronary artery in vivo using magnetic resonance imaging (MRI), and the redistribution of the cells into other organs. Methods BMMSCs were isolated, cultured from bone marrow of Chinese mini swine, and double labeled with SPIO and CMDiI(Cell TrackerTM C-7001). The labeled cells were injected into left anterior descending coronary artery through a catheter. The injected cells were detected by using MRI at 1 week,3weeks after transplantation. And different organs were harvested and evaluated the redistribution of transplanted cells through pathology. Results The SPIO labeled BMMSCs injected into coronary artery could be detected through MRI and confirmed by pathology and maintained more than 3 weeks. The SPIO labeled cells could be clearly imaged as signal void lesions in the related artery. The pathology showed that the injected cells could be distributed into the area of related artery, and the cells injected into coronary artery could be found in the lung, spleen, kidney, but scarcely in the liver, the structures of these organs remained normal. Conclusion The SPIO labeled BMMSCs injected into coronary artery can be detected by using MRI, the transplanted cells can be redistributed into the non-targeted organs.
Objective To study the growth characteristics of umbil ical cord MSCs (UCMSCs) in vitro and its effect on the nerve regeneration after spinal cord injury (SCI). Methods UCMSCs isolated from pregnant rats umbil ical cord were cultured and purified in vitro. Sixty female Wistar rats weighing (300 ± 10) g were randomized into three groups (n=20per group). UCMSCs group (group A) in which UCMSCs suspension injection was conducted; DMEM control group (groupB) in which 10% DMEM injection was conducted; sham group (group C) in which the animal received laminectomy only.Establ ish acute SCI model (T10) by Impactor model-II device in group A and group B. The recovery of the lower extremity was observed using BBB locomotor scoring system, neurofilament 200 (NF-200) immunofluorescence staining was performed to detect the neural regeneration, and then the corticospinal tract (CST) was observed using the biotinylated dextran amine (BDA) tracing. Results Cultured UCMSCs were spindle-shaped fibrocyte-l ike adherent growth, swirl ing or parallelly. The USMSCs expressed CD29, but not CD31, CD45, and HLA-DR. The BBB score was higher in group A than group B 4, 5, and 6 weeks after operation, and there was a significant difference between two groups (P lt; 0.05). The BBB scores at different time points were significantly lower in groups A and B than that in group C (P lt; 0.05). UCMSCs was proved to survive and assemble around the injured place by frozen section of the cords 6 weeks after injury. NF-200 positive response area in groups A, B, and C was (11 943 ± 856), (7 986 ± 627), and (13 117 ± 945) pixels, respectively, suggesting there was a significant difference between groups A, C and group B (P lt; 0.05), and no significant difference was evident between group A and group C (P gt; 0.05). BDA anterograde tracing 10 weeks after operation demonstrated that more regenerated nerve fibers went through injured area in group A, but just quite few nerve fibers in group B went through the injuried cavity. The ratios of regenerative axons amount to T5 axons in group A and group B were smaller than that of group C (P lt; 0.05). Conclusion UCMSCs can prol iferate rapidly in vitro, survive and differentiate to neurons after being grafted into injured spinal cord. The transplantation of UCMSCs is effective in promoting functional recovery and axonal regeneration after SCI.
Purpose To investigate the characteristics of intraocular growth of mice embryonic stem cells (ESC) in nude mice. Methods The undifferentiated murine ESC in vitro were transplanted into the eyes of nude mice.Mophological and immunohistochemical examinations were implemented. Results Two to three days after transplantation,yellowish-white granules and masses were seen inside the anterior chamber and vitreous cavity and enlarged gradually.Morphological examination showed that there were undifferentiated cells and differentiated cells in anterior chamber and vitreous cavity.The morphology and alignment of some differentiated cells were similar to those of the retina of nude mice.The cells were highly positive in NSE staining. Conclusion The transplanted ESC could grow in the eyes of nude mice and differentiate into neurons and retina-like structure. (Chin J Ocul Fundus Dis，2000，16：213-284)
Objective To introduce the basic research and cl inical appl ication of stem cells transplantation for treating diabetic foot. Methods The recent original articles about the stem cells transplantation for treating diabetic foot were extensively reviewed. Results Transplanted different stem cells in diabetic foot could enhanced ulceration heal ing in certain conditions, increase neovascularization and avoid amputation. Conclusion Stem cells transplantation for treating diabeticfoot may be a future approach．
ObjectiveTo investigate the application of autologous keratinocyte suspension transplantation in skin reconstruction. MethodsForty adult Sprague Dawley rats (weighing, 210-230 g) were randomly divided into 4 groups (n=10): high density keratinocyte suspension transplantation (1×106 cells/cm2) group (group A), middle density (1×105 cells/cm2) group (group B), low density (1×104 cells/cm2) group (group C), and control group (group D). Skin samples were harvested from the rats in groups A, B, C for the isolation of keratinocytes. The model of anti-contracture of full thickness skin wound was made in rats and autologous keratinocyte suspension was transplanted into the wound. The wound was covered by the allogeneic skin (allogeneic skin derived from Wistar rats). The survival of rats was observed after operation. The survival of allogeneic skin was observed at 7, 14, and 21 days after operation, and wound healing rate was calculated after allogeneic skin dropped off. Histological staining and immunohistochemical staining were carried out at 21 days after operation. ResultsAll the rats survived to the end of the experiment. The allograft skins survived in all groups, dried and dropped off. The epithelium sheet could be seen in groups A and B at 21 days, a few very thin epithelium in group C, and no epithelization in group D. The wound healing rate of groups A (62.9%±9.6%) and B (64.2%±9.1%) were significantly higher than that of groups C (38.5%±5.7%) and D (22.7%±5.5%) (P<0.05), and significant difference was found between groups C and D (P<0.05), but there was no significant difference between groups A and B (P>0.05). The results of histological observation showed that squamous epithelial cells were observed in groups A, B, and C, but not in group D; obvious layers of epidermis were observed in groups A and B, thin epidermis and inflammatory cell infiltration in group C, and granulation tissue in group D. The immunohistochemistry staining showed that the expressions of collagen type IV and collagen type VII in groups A, B, and C; the percentage of collagen type IV and collagen type VII positive cells in groups A and B were significantly higher than that of group C (P<0.05), but there was no significant difference between groups A and B (P>0.05). The expressions of collagen type IV and collagen type VII in group D were negative. ConclusionThe repair of full thickness skin wound with graft of autologous keratinocyte suspension can achieve reconstruction of the skin. The appropriate density of keratinocyte suspension for wound healing is 1×105 cells/cm2.
Objective To investigate the cl inical effect of MSCs transplantation derived from human umbil ical cord on bone nonunion. Methods From December 2005 to December 2007, 72 patients with traumatic bone nonunion were treated. Auto-il iac bone transplantation was used in 36 patients (group A), including 27 males and 9 females, aging (34.0 ± 2.1) years; including 18 cases of femoral fracture and 18 cases of tibia fracture; and the time of bone nonunion being (9.1 ± 1.7)months. Percutaneous MSCs transplantation derived from human umbil ical cord was used in 36 patients (group B), including 28 males and 8 females, aging (36.0 ± 1.6) years; including 18 cases of femoral fracture and 18 cases of tibia fracture; and the time of bone nonunion being (6.4 ± 1.9) months. There were no statistically significant differences in general data between two groups (P gt; 0.05). In group A, the site of bone nonunion was filled with relevant auto-il iac bone. In group B, the mixture of 6-8 mL platelet-rich plasma prepared by centrifugal izing venous blood and 1 × (106-107) P5 MSCs extracted from human umbil ical cord denoted by volunteers was injected into the region of bone nonunion with 0.2 g demineral ized bone powder. Results Incision healed by first intention in group A. No puncture, deep infection, rejection and general fever reaction occurred in group B. All patients in two groups were followed up for (13.2 ± 4.6) months. No loosening and breakage of internal fixation were observed in two groups. The motil ity and function of hip, knee and ankle were good. The time of bone union was (10.3 ± 2.8) months in group A and (5.6 ± 0.8) months in groups B, showing significant difference between two groups (P lt; 0.05). Conclusion The percutaneous MSCs transplantation derived from human umbil ical cord is more effective on bone nonunion than the traditional treatment, it is easily-to-operate, safe, rel iable, and rapid for union. It is one of effective methods in treating bone nonunion.
Objective Bone marrow mesenchymal stem cells (BMSCs) play an important role in repairing nerve injury, meanwhile external temperature has significant effect on BMSCs transplantation, prol iferation, and differentiation. To investigate the effect of BMSCs transplantation and mild hypothermia on repair of rat spinal cord injury (SCI). Methods Forty-five female adult SD rats (weighing 200-250 g) were made the models of hemitransection SCI and divided randomly into 3 groups according to different treatments: group A (SCI group), group B (BMSCs transplantation group), and group C [BMSCs transplantation combined with mild hypothermia (33-35 ) group]. At 1, 2, 4, 6, and 8 weeks after injury, the fuction of hind l imb was evaluated with Basso Beattie and Bresnahan (BBB) score and incl ined plane test. At 4 weeks after injury, histopathology and BrdU immunohistochemistry staining were performed. At 8 weeks after injury, horseradishperoxidase (HRP) retrograde nerve trace and transmission electron microscope (TEM) testing were performed to observe the regeneration of axon. Results After 4 weeks, the function of hind l imb obviously recovered in groups B and C, there were significant differences in BBB score between groups B, C and group A (P lt; 0.05), between group B and group C (P lt; 0.05). There was no significant difference (P gt; 0.05) in tilt angle among 3 groups after 1 and 2 weeks, and there were significant differences (P lt; 0.05) among 3 groups after 4 weeks. HE staining showed that significant cavity could be seen in group A, l ittle in group B, and no cavity in group C. BrdU immunohistochemistry staining showed that the number of positive cells was 0, 90.54 ± 6.23, and 121.22 ± 7.54 in groups A, B, and C, respectively; showing significant differences (P lt; 0.01) among 3 groups. HRP retrograde neural tracing observation showed that the number of HRP positive nerve fibers was 10.35 ± 1.72, 43.25 ± 2.65, and 84.37 ± 4.59 in groups A, B, and C, respectively, showing significant differences (P lt; 0.01) among 3 groups. TEM observation showed that a great amount of unmyel inated nerve fibers and myel inated nerve fibers were found in central transverse plane in group C. Conclusion The BMSCs transplantation play an impontant role in promotion of recovering the function of hind l imb after SCI, and mild hypothermia has synergism effects.
Objective To investigate the latest research and the therapeutic development in the injuries to the spine and spinal cord. Methods Literature concerned was reviewed, combined with our own research and clinical experience, to summarize the trend of the researches and their clinical application in the treatment of the injured spine and spinal cord.Results Theposterior approach atlantoaxial stabilization technique changed the conventional wiring technique into the transarticular screw fixation to the plate and pedicle or the lateral mass screw fixation technique. Theclinical application of the transoralpharyngeal atlantoaxial reduction plate fixation technique showed a good effect on the reduction of atlantoaxial dislocation. However, there were no unified criteria for selection of the surgical approach, fixation level, and fusion mode in the treatment of thoracolumbar spinalfractures. Under optimal conditions, both the anterior and the posterior approaches could achieve good clinical effects on decompression and spinal reconstruction. The single level fixation technique showed some advantages in treating certaintypes of thoracolumbar spinal fractures when compared with the traditional cross-sectional fixation. The endoscopy-assistant and image-guiding spinal intervention techniques were evolved in China during these years. In the treatment of the obstinate painful osteoporotic vertebral compressive fracture, percutaneous vertebroplasty and kyphoplasty achieved good results in the pain relief and spinal reconstruction. Numerous basic and clinical researches have given us a further understanding of the medical protection of acute spinal cord injury, and biological treatments have given us new ideas on neural reparation and regeneration. Cell transplantation and gene therapy have become the most promising treatment strategies in this field.Conclusion With the rapid development of spine surgery, the repair and reconstruction ofthe injured spine and spinal cord made a great stride in the recent years.
Objective To investigate the synergistic effect of a combination of grafted olfactory ensheathing cells (OECs) from the olfactory bulbs and intrathecal injection of vascular endothel ial growth factor (VEGF) on repairing spinal cord injury, and to explore the neuroprotection on both neurons and nerve fibers. Methods OECs from neonatal rats were cultured, purified, and collected with 0.25% trypsin after 9 days. A total of 75 adult female Wistar rats (weighing 200-250 g) were randomly divided into 5 groups: group A was sham-surgery group receiving laminectomy; the spinal cord injury model was establ ished with weight-dropped apparatus in the rats of groups B, C, D, and E. Then group B was injected with 10 μL DMEM-F12 medium without serum at injury site on the 1 day and was intrathecally administrated with 10 μL sal ine solutiontwice a day during the following 1 week; group C was injected with 10 μL DMEM-F12 medium and 25 ng recombined ratVEGF165 (rrVEGF165); group D was injected with 10 μL DMEM-F12 medium containing 1 × 105 OECs and 10 μL sal ine solution; group E was injected with 10 μL DMEM-F12 medium containing 1 × 105 OECs and 25 ng rrVEGF165. The functional recovery of hindl imb was evaluated by the Basso-Beattie-Bresnahan (BBB) score at 1 day and each week from 1 to 8 weeks. The histological changes and the changes of ultrastructure were observed at 8 weeks after operation by HE and electron microscope, and the immunohistochemistry staining was used for p75 nerve growth factor receptor (p75NGFR), Caspase-3, and von Willebrand factor (vWF). Results The function of hindl imb recovered rapidly in group E; the BBB score reached the peak at 8 weeks, and it was significantly higher than those in other groups (P lt; 0.05). The histology and ultrastructure observation showed that nerve fibers and neurons were damaged seriously in group B, oderately in groups C and D, and sl ightly in group E. Numerous spared tissue between nerve stumps, fibers with regular myel ination, and neurons with l ittle vacuolar mitochondria were observed in group E. The immunohistochemistry staining revealed that Caspase-3 positive cells in groups B, C, D, and E were significantly more than that in group A (P lt; 0.05); more Caspase-3 positive cells were found in groups B and D than in groups C and E (P lt; 0.05), while no significant difference was found between groups C and E (P gt; 0.05). And more vessels per high field were examined in groups C and E than in groups A, B, and D (P lt; 0.05), while no significant difference was found between groups C and E (P gt; 0.05). The p75NGFR positive results showed the survival of OECs in groups D and E at 8 weeks after OECstransplantation. Conclusion Grafted OECs combined with intrathecal injection of VEGF has significant promotive effects on restoration of spinal cord injury in rats, can improve part function of nerve fibers, and shows neuroprotection on damaged cells and fibers, which have a synergistic effect.
Objective To introduce the research of cell transplantation for treating intervertebral disc degeneration. Methods The original articles in recent years about cell transplantation for treating intervertebral disc degeneration were extensively reviewed, and retrospective and comprehensive analysis was performed. Results Transplantation of intevertebraldisc-derived cells or BMSCs by pure cell transplantation or combined with collagen scaffold into intervertebral disc couldexpress nucleus pulposus-l ike phenotype. All the cells transplanted into intervertebral disc could increase extracellular matrix synthesis and rel ieve or even inhibit further intervertebral disc degeneration. Conclusion Cell transplantation for treating intervertebral disc degeneration may be a promising approach.