Purpose To investigate the development of embryonic stem cells (ESC)in the subretinal space． Methods ESC were cultivated in suspension for 4 days till they developed into cell aggregates,i.e.embryonic body(EB).ESC as well as EB combined with or without RA were respectively transplanted into vitreous cavity and subretina1 space in SD rats,and the subretinal transplanted eyes,transient ischemia-reperfusion injuries were made by ligating the ophthalmic artery for 40 seconds before the transplantation .The experimental eyes were enucleated for histological and immunohistochemical assays after 14～28 d. Results The EB was found to develope into photoreceptors induced by RA in the subretinal space under an ischemia-reperfusion condition，and EB transplantation without RA induction induced multiple differentiations in the subretinal space.The single injection of RA without EB induced hyperplasia of the neural retinal cells.ESC transplanted into vitreous cavity rapidly proliferated and developed into atypical hyperplastic mass. Conclusion EB derived from ESC can differentiate into photoreceptors induced by RA in the host subretinal space under an ischemia-reperfusion condition. (Chin J Ocul Fundus Dis，2000，16：213-284)
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 summarize the research progress of stem cell transplantation in treating spinal cord injury (SCI) at different stages based on the pathophysiological mechanism of SCI. Methods The relevant research literature at home and abroad was extensively reviewed to explore the impact of transplantation timing on the effectiveness of stem cell transplantation in treating SCI. Results Researchers performed different types of stem cell transplantation for subjects at different stages of SCI through different transplantation approaches. Clinical trials have proved the safety and feasibility of stem cell transplantation at acute, subacute, and chronic stages, which can alleviate inflammation at the injured site and restore the function of the damaged nerve cells. But the reliable clinical trials comparing the effectiveness of stem cell transplantation at different stages of SCI are still lacking. Conclusion Stem cell transplantation has a good prospect in treating SCI. In the future, the multi-center, large sample randomized controlled clinical trials are needed, with a focus on the long-term effectiveness of stem cell transplantation.
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 effect of intravitreal injection of FK506 on the survival of human retinal pigment epithelial (RPE) cells heter oplastically transplanted into the subretinal space of rabbits.Methods The immortalized human RPE cells were genetically labeled by retrovirus vector carrying a green fluorescent protein (GFP). A total of 50 μl RPE cells suspension with 4×103 cells/μl which expressed GFP were injected into the subretinal space of both eyes of 18 white rabbits and 10 gray rabbits. The left eyes of all of the rabbits were injected of 5 μl FK506 (5 μg/μl) intravitreally once a week during the first 5 weeks, then once every other week until the 20th week and the right eyes were as the control. The histological sections of heteroplastic RPE cells were observed by epifluorescent microscope.Results GFP-expressing cells could be seen after 1 week, 2, 3, 4, 6, 10, 11, 14, 18, 20, 23, 24, 25, 26, 33, and 54 weeks in white rabbits and after 4 , 5, 6, 7, 14, 18, 20, and 26 weeks in gray rabbits. The configuration and integrality of the RPE-GFP cells in the left eyes which had been intravitreally injected of FK506 1-14 weeks after transplantation were better than those in the right eyes without injection. After 18 weeks, the condition of heteroplastic cells with few difference in both eyes in 7 white and 3 gray rabbits were found. After 1-6 weeks, focal and disseminated lymphocytes around the choroidal small vessles of right eyes in 6 white and 3 gray rabbits could be seen while the infiltration of the lymphocytes in the left eyes was much reduced.Conclusion Intravitreal injection of a small amount of FK506 at the first 3 months after transplantation may significantly improve the survival of heteroplastic RPE cells in the subretinal space of rabbits. (Chin J Ocul Fundus Dis，2003，19：333-404)
Objective To review the status and appl ication prospect in repair of spinal cord injury by stem cells. Methods The related articles in recent years were extensively reviewed, the biological characteristics of stem cells, the experimental and cl inical studies on repair of spinal cord injury by stem cells, the mechanism of the therapy and the problem were discussed and analyzed. Results The foundational and cl inical study indicated that the great advance was made in repair of spinal cord injury, the stem cells could immigrate in the spinal cord, and differentiate into neuron and secrete neurotrophic factors. So it could promote the repair effects. Conclusion Repair of spinal cord injury by stem cells is an effective therapystrategy, but many problems remain to be resolved.
Objective To investigate the synergetic effect and possibil ity of repairing spinal cord injury (SCI) by transplantation of olfactory ensheathing cells (OECs) and chondroitinase ABC (ChABC) in adult rats. Methods Three adult male SD rats were used to isolated olfactory bulb and primarily cultured OECs. In the 8th or 9th day, OECs were transplanted, the concentration of cells was modulated to 1 × 105/μL. Fifty-four SD rats were made the models of T8 spinal cord crush injury and divided into 4 groups. In group A (control, n=36), injured site was not treated; in groups B, C and D (n=6), OECs, ChABC and OECs+ChABC were injected into injured site, respectively. At 1, 2, 3, 7 and 14 days after injury, the BBB score system was used to evaluate the motion function. At 0, 1, 2, 3, 7, 14 days in group A and at 14 days in groups B, C, D after injury, the maximal transverse diameter and gross area of necrosis were evaluated on HE stained sections. The immunofluorescence double label ing staining for gl ial-fibrillary acidic protein (GFAP)/CS56, GFAP/growth associated protein 43(GAP-43) and GFAP/neurofilament 160(NF160) was carried out to evaluate the regeneration of nerve fiber. Results At 14 days after injury, there were significant difference in the BBB scores between group A and groups B, C, D (P lt; 0.05), and between groups B, C and group D (P lt; 0.05), HE staining showed that the formation of cavity was observed in each group at 14 days after injury. There were significant difference in the maximal transverse diameter and gross area of necrosis between groups B, C, D and group A (P lt; 0.01), and between groups B, C and group D (P lt; 0.01). The immunofluorescence staining indicated that expression of GFAP were more intense in group A than in other groups, and the cavity of the lesion site was apparent, but it was moderate in groups B and C. The expression of GAP-43 was more intense in group D than in groups B and C. The expression of NF160 was more intense in group D. Conclusion Transplantation strategy of OECs combined with ChABC was effective in the repair of SCI in some extent.
【Abstract】 Objective To investigate the effects on forming of hypertrophic scar after BMSCs infected with adenovirus carrying TGF-β3c2s2 were transplanted into the wound of animal scar model. Methods The third passage of rabbit’ s BMSCs were infected with 150 mutiple infection, and were cultured 24 hours. The concentration of the BMSCs infected with recombinant adenovirus containing the TGF-β3c2s2 gene was 1×105cell/mL. The purified and evaporated recombinant adenovirus grains containing the TGF-β3c2s2 gene were diluted by DMEM/F12 (without FBS) to 1×108 pfu/mL. The animal scar model of the standard Japanese big ear rabbit was establ ished. Eighty wounds were generated on the gastroside of ear and were randomized to 4 groups in each rabbit, which were divided into 3 control groups (A: control, B: Ad-TGF-β3c2s2, C: BMSCs) and 1 experimental group (D: BMSCs/Ad-TGF-β3c2s2). Then the wounds were tranplanted with cells. On 45 days and 90 days after wounded, thicknessand hardness of scars were measured with color ultrasound diagnostic unit and especial measurement for skin and scar hardness. On 21, 45 and 90 days, three specimens were harvested respectively for further histological study. Results The wound of groups A, B, C gradually formed the different degree scars after epithel ial ization. The hyperplasty of scars reached peak on 45 days after wounded and lasted about 90 days. There was no prominent scar formed in group D during the whole observed procedure. Thickness and hardness of scar of group D and group E were approximate on 45 days and 90 days. Thickness and hardness of scar of groups A, B and C were lower than those of group D (P lt; 0.01), and group B showed more lower than group A and group C (P lt; 0.01). Disorder structure and overlapping arrangement, enlargement collagen fibers were showed in the HE histological sections of the scars of groups A, C. The structure of the scars of groups B, C were similar to Group E. The constitutionsof groups A, B, C, D on 90 days resembled to each one on 45 days. In section of immunohistochemistry after wounded on21 days and 45 days, positive expressions of BrdU in nucleus of Groups C, D were observed. Negative expressions of BrdU in Groups A, B, E were showed. Conclusion BMSCs with Ad-TGF-β3c2s2 gene transplanted into wound could inhibit the forming of hypertrophic scar.
Objective To observe the effects of subretinal transplantation of rat mesenchymal stem cells (rMSCs) on Sodium Iodate (SI)induced retinal degeneration. Methods One hundred and twenty BrownNorway (BN) rats were divided into three groups including SI injection group,rMSCs transplantation group and normal control group, each with 40 rats. The retinal degeneration was induced by caudal vein injection of SI. The retinal pigment epithelium（RPE）and neural retinal were evaluated by ocular fundus photograph, fluorescein fundus angiography (FFA)，electroretinogram (ERG) and histological approach, and TUNEL（terminal deoxynucleotidyl transferasemediated dUTP nick end labeling ）. CMDiIprelabeled primary rMSCs were transplanted into the subretinal space of SIinduced rats. The survival, integration, and differentiation of rMSCs were observed between 14 day to 60 day after the transplantation.Results The rat retinal function was gradually reduced after14 days of SI injection, with a timedependent manner. After the RPE cells were damaged，the outer segments of photoreceptors became disrupted and shortened until karyopyknosis. The nuclear morphology and positive TUNEL labeling indicated that the death of photoreceptor cells was apoptosis. After rMSCs transplantation, CMDiI labeled donor cells were observed to be scattered in the subretinal space and expressed RPE cell markers. Average amplitude of b wave and Ops (oscillation potential) in ERG improved 27.80%,59.38% respectively after rMSCs transplantation.Conclusions Transplanted rMSCs can survive in subretinal space and differentiate into RPE.