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.
Age-related macular degeneration (AMD) is an age-related neurodegenerative eye disease characterized by degeneration and progressive death of retinal pigment epithelium (RPE) and photoreceptor cells. In recent years, as a new treatment for AMD, stem cell therapy has attracted wide attention in the field of AMD, and has become a current research hotspot. Although stem cell therapy carries risks such as increased incidence of cancer and immune rejection, it significantly promotes damaged photoreceptor cells and retinal cells by differentiating into RPE cells and other retinal cell types, as well as secreting neurotrophic factors and extracellular vesicles. In particular, the development of embryonic stem cell-derived RPE cells, its cryopreservation technology and the advancement of plasmid, adeno-associated virus, Sendai virus and other delivery technologies have laid a solid foundation for stem cell therapy of AMD. As a new method to prevent retinal damage and photoreceptor degeneration, stem cell neuroprotective therapy has shown great potential, and with the continuous maturity and improvement of these technologies, stem cell therapy is expected to provide new ideas for the prevention and treatment of AMD in the future.
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)
Objective To review the application advancements of ATP-binding cassette (ABC) transporter in medical research.Methods Relevant literatures about the applications of ABC families in medical research were reviewed. Results ABC families mainly took roles in transporting substances across cell membrane. Some of them were useful for the prediction of drug resistance and the prognosis of malignant tumors. Others were target s for molecular researches. Their expressions or mutations might be related with the occurrence of diseases. Conclusion ABC families are very important in the diagnosis and therapy for diseases. Thus they are very promising tools for future medical research.
Objective To review the advance in the experimental studies of microRNA(miRNA) and the relationship between miRNA and stem cells. Methods The related literature was reviewed, and the research findings of miRNA and stem cell were summarized. Results miRNA was noncoding small RNA (20-25 nt) involved in posttranscriptional change, that have been shown to regulate gene expressions. Ithas been reported that some kinds of miRNAs were likely important regulators forstem cells maintaining their state of selfrenewal，and play key roles in theirdifferentiation. Conclusion miRNA as regulation of gene expressions, can be served as a new way for stem cells research.
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.
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 investigate the biological mechanism about autologous peripheral blood stem cell transplantation （ABSCT） derived neovascularization to lead and perfect the effect of ischemic state tissue of secondary blood flow remodeling. Methods Forty-two patients with critical limbs ischemia and 42 limbs in all from Mar. 2005 to Dec. 2005 in Yunnan Provincial Center of Vascular Surgery were selected，who treated by endovascular repair and ABSCT at the first flow reconstruction and the secondary flow reconstruction，respectively. The preoperative and postoperative effect degrees of limbs regional blood flow from cutaneous covering，blood vessel，and blood were measured by multifunction monitoring device，dopplor ultrasound monitoring device，percutem oxygen partial pressure （TcPO2）monitoring device and digital subtraction angiography （DSA）. The follow-up time was in four year after ABSCT.Results After ABSCT， the pain，cold or cool，and rest pain of leg were relieved. The distance of intermittent claudication after ABSCT was longer than that before ABSCT 〔（1 600.3±310.1） m versus （520.3±160.6） m，F=5.84，P＜0.05〕. The foot pain and limbs insensible feeling easement rates were 100% after ABSCT. Compared with beforeABSCT，the objective effect indexes of limbs regional blood flow after ABSCT were significantly improved 〔skin temperature index：1.63±0.31 versus 1.22±0.23，F=4.69，P＜0.05； TcPO2： （37.61±9.52） mm Hg versus （30.63±4.54） mm Hg，F=5.72，P＜0.05；ankle-brachium index：0.93±0.23 versus 0.33±0.24，F=6.72，P＜0.05；photoplethysmography index：0.81±0.12 versus 0.23±0.05，F=5.68，P＜0.05；saturation of blood oxygen： （79.44±20.42）% versus （42.43±10.41）%，F=5.68，P＜0.05； DSA score：1.34±0.23 versus 0.21±0.03，F=4.89，P＜0.05〕. Conclusions The results bly suggest that the ABSCT can promote blood flow remodeling in limbs ischemia，and stem cells derived neovascularization can significantly offer effective and permanent blood flow perfusions to the ischemic statetissue，and this biological effect play an important role in the ischemic state tissue for secondary blood flow remodeling.