Objective To review the latest research progress of full-thickness tissue engineered skin (FTTES), to thoroughly understand its current state of research and appl ication so as to lay a sol id foundation for developing new type FTTES and improving the qual ity of skin substitutes. Methods Domestical and international l iterature concerning FTTES in recent years was extensively reviewed and comprehensively analyzed. Results Some progress of FTTES had made in seedcells, scaffold materials and construction, and some therapeutic efficacy had also been achieved in cl inical appl ication. ButFTTES grafting successful rate was lower, and it had no complete skin structure and had not reached the requirements of cl inicalappl ication. Conclusion FTTES is an ideal skin substitute and has great development prospects. However, in seed cells, scaffold materials, construction and appl ications of FTTES, further studied is still needed.
Objective To observe whether transforming growth factor-beta;2（TGF-beta;2）could promote the differentiation of retinal stem cells in rats cultured in vitro. Methods The retinal stem cells were separated from the embryonic ratsprime; eyes under the dissecting microscope, cultured, and subcultured. The cells were identified by nestin and Chx-10 immunofluorescence. The sixth generation of cells were induced and differentiated, immunofluorescent stained with anti-glial fibrillary acidic protein，anti-opsin, anti-b-tubulin, and anti-protein kinase C, and identified the final cells. Results The cultured cells after induced by TGF-beta;2 differentiated to the mature cells. The results of immunofluorescence showed that the differentiated cells induced by TGF-beta;2 were more than which induced by the embryonic bovine blood serum. Conclusion TGF-beta;2 may induce the retinal stem cell differentiating into retinal cells. The inductive and differentiating effect of TGF-beta;2 is ber than which of the blood serum. (Chin J Ocul Fundus Dis, 2007, 23: 104-107)
Objective To isolate and purify the melanoma stem cells (MSC) in choroidal melanoma OCM-1 cells. Methods OCM-1 cells were resuscitated, and after cultured in standard Dubecco's modifided Eagle's medium (DMEM)/F12, they were cultured in serum-free medium (SFM). The cultured MSC were isolated and purified, and the positive rate of CD133, the specific markers of neurostem cells, was observed by flow cytometry (FCM). The 6th generation of the cells were stained by musashi-1 immunocytochemistry, and the rate of the positive cells was observed under the microscope. Results After the Adherent OCM-1 cells cultured in SFM, the number of the adherent number decreased obviously. The cells at the 6th generation grew as the suspended gobbets, which represented the typical grow manner of the stem cells. Positive CD133 could be found in the cells of different generations, which was 2.5％, 21.7％, and 57.8％ in the non-isolated OCM-1 cells, the 1st generation of isolated cells, and the 2nd generation cells, respectively. The positive rate of CD133 in the cells at the sixth generation was 79.8% with b positive expression of musashi-1. Conclusion MSC is in the human choroidal melanoma OCM-1 cells. The suspended stem cells may be purified by limited differentiation and serial passage in SFM. (Chin J Ocul Fundus Dis, 2007, 23: 87-90)
Objective To study the effect of different types of supernatants fluid of retinal cells on the physiological function of neuron cells derived from embryonic stem cells. Methods Embryonic bodies were sub-induced by retinoic acid (group A), retinoic acid with the supernatant fluid of retinal glia cells and neurons of mouse (group B), retinoic acid with the supernatant fluid of fetal retinal glia cells (group C), respectively. The Sodium ion channels on the cytomembrane in the 3 groups were analyzed 5-21 days after the inducement. Results The sodium current in each group didn't change much 5-21 days after the inducement. The sodium channels presented burst-opening discharge in group A, brief-opening discharge in group B, and long-opening discharge in group C. The percentage of the cells without current in group A, B and C was 25%, 11.4%, and 23.8%, respectively, but the difference was not significant among the 3 groups(Pgt;0.05). The number of cells with sodium current increased at first and decreased later in group A, continuously increased in group B, and decreased at first and kept stable later in group C. The open time of sodium channels was the longest in group A, and the shortest in group B. The distribution of open time in the three groups could be managed with two-step exponential fit. Conclusion The supernatant fluid of retinal cells has apparent influence on the physiological function of the neuron cells derived from embryonic stem cells. (Chin J Ocul Fundus Dis, 2007, 23: 91-93)
ObjectiveTo investigate the effects of hypoxia inducible factor 1α (HIF-1α) overexpression on the differentiation of stem cells derived from human exfoliated deciduous teeth (SHED) into vascular endothelial cells.MethodsSHED was isolated from the retained primary teeth donated by healthy children by using collagenase digestion method. The third generation cells were identified by flow cytometry and alizarin red and alkaline phosphatase (ALP) staining after osteogenic differentiation culture. The SHED were divided into blank control group (SHED without any treatment), empty group (SHED infected with empty lentivirus), HIF-1α overexpression group (SHED infected with HIF-1α overexpression lentivirus), Wnt inhibitor group (SHED interfered by IWR-1), and combination group (HIF-1α overexpressed SHED interfered by IWR-1). Real-time fluorescence quantitative PCR (qRT-PCR) and Western blot were used to analyze the expressions of HIF-1α mRNA and protein in the SHED of blank control group, empty group, and HIF-1α overexpression group. Then the SHED in 5 groups were induced differentiation into vascular endothelial cells for 14 days. The expressions of cell surface marker molecule [von Willebrand factor (vWF) and CD31] were detected by flow cytometry. The mRNA expressions of vascular cell adhesion protein 1 (VCAM-1), KDR (Kinase-inserted domain containing receptor), and VE-cadherin (VE) were analyzed by qRT-PCR. The protein expressions of phosphate-glycogen synthasc kinase 3β (p-GSK3β) and β-catenin were analyzed by Western blot. The tube forming ability of induced cells was detected by Matrigel tube forming experiment. The ability of endothelial cells to phagocytic lipid after differentiation was detected by DiI-labeled acetylated low density lipoprotein (DiI-Ac-LDL) phagocytosis.ResultsAfter identification, the cells were SHED. After lentivirus transfection, compared with the blank control group and the empty group, the expressions of HIF-1α mRNA and protein in the HIF-1α overexpression group increased significantly (P<0.05). Compared with the blank control group and the empty group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly higher (P<0.05), the relative expression of p-GSK3β protein was significantly lower (P<0.05), the number of tubules formed and the ability to phagocytic lipids significantly increased (P<0.05) in the HIF-1α overexpression group; while the indicators in the Wnt inhibitor group were opposite to those in the HIF-1α overexpression group (P<0.05). Compared with the HIF-1α overexpression group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly lower (P<0.05), the relative expression of p-GSK3β protein was significantly higher, and the number of tubules formed and the ability of phagocytosis of lipids significantly reduced, showing significant differences between groups (P<0.05).ConclusionOverexpression of HIF-1α can promote SHED to differentiate into vascular endothelial cells by activating Wnt/β-catenin signaling pathway.
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 summarize the progress of the roles and mechanisms of various types of stem cell-based treatments and their combination therapies in both animal studies and clinical trials of lymphedema. MethodsThe literature on stem cell-based treatments for lymphedema in recent years at home and abroad was extensively reviewed, and the animal studies and clinical trials on different types of stem cells for lymphedema were summarized.ResultsVarious types of stem cells have shown certain effects in animal studies and clinical trials on the treatment of lymphedema, mainly through local differentiation into lymphoid endothelial cells and paracrine cytokines with different functions. Current research focuses on two cell types, adipose derived stem cells and bone marrow mesenchymal stem cells, both of which have their own advantages and disadvantages, mainly reflected in the therapeutic effect of stem cells, the difficulty of obtaining stem cells and the content in vivo. In addition, stem cells can also play a synergistic role in combination with other treatments, such as conservative treatment, surgical intervention, cytokines, biological scaffolds, and so on. However, it is still limited to the basic research stage, and only a small number of studies have completed clinical trials. ConclusionStem cells have great transformation potential in the treatment of lymphedema, but there is no unified standard in the selection of cell types, the amount of transplanted cells, and the timing of transplantation.
Objective To summarize the research situation of stem cells transplantation for intervertebral disc (IVD) degeneration. Methods The original articles about stem cells transplantation for repair of IVD degeneration were extensively reviewed; the clinical applications, the mechanisms, and related factors to influence repair effect were analyzed; and obstacles in stem cells transplantation for repair of IVD degeneration. Results Autogenic stem cells transplantation can repair IVD degeneration and effectively relieve the symptoms of low back and leg pain. Stem cells can differentiate into disc chondrocytes in the disc microenvironment, increase the production of various growth factors, and exert a trophic effect on disc cells. It is also evident that the transplanted stem cells can potentially protect disc cells from apoptosis and maintain an immune-privileged state in the IVD. Multiple factors such as tissue origin of stem cells, methods to pre-modulate the seeds, choice of injectable scaffolds, and even the severity of degeneration are closely related to the repair effects. To get a more efficient stem cell therapy, future researches are challenged to modulate the migration and distribution of stem cells in the IVD, avoid flow back, and better understand their ability to restore stemness properties within the degenerative disc niche. Conclusion Stem cells transplantation is proven to be a promising biological approach for repair of IVD degeneration.
ObjectiveTo observe the role of Notch signaling pathway inhibitor in differentiation process of stem cells derived from retinal Müller cells into the ganglion cell. MethodsRetinas of Sprague Dawley rat at postnatal 10-20 days were dissociated from eye balls. The third passage of Müller cells was used in this experiment, which cultured by repeated incomplete pancreatic enzyme digestion method. The retinal Müller cells were induced in the serum-free dedifferentiation medium. The cell proliferation state was observed under an inverted microscope. The expression of the specific markers Nestin and Ki-67 of retinal stem cells was measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The positive rate of nucleus was detected by Edu. The retinal stem cells was divided into Gamma secretase inhibtor-I (GSI) group and control group, the rate of ganglion cells was counted by using immunofluorescence staining. ResultsThe cell proliferation had gathered to form a sphere. Immunofluorescence staining showed that the expressions of Nestin and Ki-67 were (92.94±6.48%) and (85.96±6.04%) respectively. Edu positive rate of nucleus was (82.80±6.65)%. RT-PCR and Western blot further confirmed the high expression of Nestin and Ki-67 in the cell spheres but not in the Müller cells. The positive rate of ganglion cells were (16.98±2.87)% and (11.17±0.71)% in GSI group and control group respectively, with the significant difference (t=3.210, P=0.002). ConclusionNotch signaling pathway is an important regulatory gene in stem cells differentiated into retinal ganglion cell.
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.