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 investigate the latest development of tissue engineeredregenerative medicine in industrialization, with the intention to direct work in practical area. Methods A complete insight of regenerative medicine in industrialization was obtained through referring to update publications, visiting related websites, as well as learning from practical experience. Results The aerial view of the future of regenerative medicine was got based on knowledge of four different tissue engineering projects. Conclusion All present efforts should be devoted to regenerative medicine area meeting the industrialized trends.
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)
Stem cells belong to a subgroup of undifferentiated cells in organisms, which has the features of proliferation, self maintaining, and self renewal, and may produce plentiful filial generation with functions. According to the researches on embryonic stem cells, retinal stem cells in adults, and intraocular tumor stem cells, stems cells exist in human embryo, adult retina, and also intraocular tumors like retinoblastoma and choroidal melanoma. Different stem cells transplanted into subretinal interspace or vitreous cavity may differentiate into structure of neurone or retina. Stem cells may become a newest target of the researches on pathogenesis and treatment of diseases. (Chin J Ocul Fundus Dis, 2007, 23: 83-86)
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 investigate the possibility of commitment differentiation of embryonic stem cells induced by the medium of cultured retinal neurons of SD rats. Methods The medium from cultured retinal neurons of SD rats were collected, sterilized and mixed with DMEM medium according to 2∶3 proportion, ES cells were cultured with these mixed medium and were observed under the phase contrast microscope daily, the induced cells were identified by NF immunohistochemistry methods. Results The ES cells cultured with these mixed medium can differentiate into neuron-like structure, and the induced cells were positive in NF immunofluorescence staining. Conclusion The medium from cultured retinal neurons of SD rats can induce ES cells commitment differentiation into neuron-like structure. (Chin J Ocul Fundus Dis, 2002, 18: 134-136)
Magneticaly labeled stem cells and magnetic resonance imaging(MRI) technology is an effective tracking method in vivo study, which has high spatial-temporal resolution. Gadolinium, which shows positive T1 signals and iron oxide showing negative T2 signals are the two often used contrast agents. The latter also include superparamagnetic iron oxide particle and ultrasmall superparamagnetic iron oxide particle. Transfection agents, e.g. poly-L-lysine and protamine sulfate，can enhance magnetical nanoparticles labeling stem cells. The biological characteristics of labeled stem cells did not seem to be altered. MRI can detect the labeled stem cells’ signals and also can track changes of signal in intensity and size with time past. In conclusion, MRI tracking magneticaly labeled stem cells represents a method for noninvasivly monitoring the existence and migration of engrafts.
Objective To review the recent progress of the researches in the field of cartilage tissue engineering, and to discuss the challenges in construction of tissue engineered cartilage. Methods Literature related with cartilage tissue engineering was reviewed and analyzed. Results Some techniques have been appl ied in cl inical. As far as the seeding cells, induced pluripotent stem cells have attracted much more attention. Current strategies of scaffold designing are trying to imitate both component and structure of natural extracellular matrix. Cartilage regeneration through the autologous cell homing technique el iminate the transplantation of exotic cells and has become the hot topic. Conclusion Successful treatment of the damaged cartilage using tissue engineering method will depend on the advances of stem cell technology development, biomimetic scaffolds fabrication and proper appl ication of growth factors.
ObjectiveTo review the recent research progress of different types of stem cells in the treatment of ischemic stroke.MethodsBy searching the PubMed database, a systematic review had been carried out for the results of applying different types of stem cells in the treatment of ischemic stroke between 2000 and 2020.ResultsStem cells can be transplanted via intracranial, intravascular, cerebrospinal fluid, and intranasal route in the treatment of ischemic stroke. Paracrine and cell replacement are the two major mechanisms of the therapy. The researches have mainly focused on utilization of neural stem cells, embryonic stem cells, and mesenchymal stem cells. Each has its own advantages and disadvantages in terms of capability of migration, survival rate, and safety. Certain stem cell therapies have completed phase one clinical trial.ConclusionStem cells transplantation is feasible and has a great potential for the treatment of ischemic stroke, albeit that certain obstacles, including the selection of stem cells, transplantation strategy, migration ability, survival rate, still wait to be solved.