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)
Urine-derived stem cells are a kind of cells with strong proliferative ability and multi-directional differentiation characteristics of mesenchymal stem cells isolated from urine. Urine-derived stem cells are derived from the kidney and express mesenchymal stem cell-specific antigens; experimental studies have shown that they can differentiate into a variety of cells such as adipocytes, chondrocytes, bone cells, nerve cells, etc., and have the function of promoting tissue repair. A review of the research progress of urinary stem cells is now available.
Objective To summarize the research progress of CD90 protein. Methods The demestic and international published literatures related to CD90 protein in recent years were collected and reviewed. Results CD90 protein was involved in the cell-cell and cell-cytoplasm function. CD90 protein could promote axons growth and neural regeneration， and could induce apoptosis of thymus gland cells and stromal cells. CD90 protein participated in cell adhesion， extravasation and transfer， and the regulation of fibrosis. CD90 protein was a potential marker for cancer stem cells. Conclusion CD90 protein is very important in development of many diseases， and can provide a new molecular target to diagnose and treat neoplasms.
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)
Organoids are three-dimensional structures formed by self-organizing growth of cells in vitro, which own many structures and functions similar with those of corresponding in vivo organs. Although the organoid culture technologies are rapidly developed and the original cells are abundant, the organoid cultured by current technologies are rather different with the real organs, which limits their application. The major challenges of organoid cultures are the immature tissue structure and restricted growth, both of which are caused by poor functional vasculature. Therefore, how to develop the vascularization of organoids has become an urgent problem. We presently reviewed the progresses on the original cells of organoids and the current methods to develop organoids vascularization, which provide clues to solve the above-mentioned problems.
Objective
To investigate the viability and the characters of proliferation and differentiation of retinal stem cells (RSCs) after cryopreservation and anabiosis.
Methods
The RSCs of a Long Evans rat with the embryonic age of 17 days were separated and cultured in vitro. The third-passage RSCs in the cryopreservation liquid consisted of 80% Dulbecco modified Eagle medium (DMEM)/F12，10% bovine serum albumin (BSA)，10% dimethylsulfoxide (DMSO)，and basic fibroblast growth factor (bFGF) (20 ng/ml), were stored in liquid nitrogen. After 1, 2, 4, 8, 12, and 16 weeks of freezing period, these cells were thawed. The livability of the cells was counted and the differentiation was induced while the proliferation and characters of differentiation were detected by immunofluorescence.
Results
The effects of different durations of cryopreservation on the livability of RSCs did not differs much (Pgt;0.05). These cells were reculturd well and presented specific marker of RSCs. In addition, they also could be induced and differentiated into several types of retinal cells.
Conclusion
Cryopreservation and anabiosis of RSCs does not affect the cellular intrinsic characters of proliferation and differentiation.
(Chin J Ocul Fundus Dis, 2007, 23: 94-97)
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 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)
Stem cells are crucial for embryonic development and in the maintenance of adult cellular homeostasis. Understanding the regulatory network of stem cells, including embryonic and adult stem cells, will allow us to learn the pathogenesis and possibly design novel approaches to treat many diseases (such as cancer and degeneration). The retinoblastoma (Rb) pathway controls cellular proliferation, differentiation and death. More and more evidences support an important role of Rb activity in the biology of stem and progenitor cells. Transiently inactivating Rb pathway might favor the expanding of functional stem cell populations, thus have values in the future stem cell applications.
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.
