Transplantation of human neural stem cells into the dentate gyrus or ventricle of rodents has been reportedly to enhance neurogenesis. In this study, we examined endogenous stem cell proliferation and angiogenesis in ...Transplantation of human neural stem cells into the dentate gyrus or ventricle of rodents has been reportedly to enhance neurogenesis. In this study, we examined endogenous stem cell proliferation and angiogenesis in the ischemic rat brain after the transplantation of human neural stem cells. Focal cerebral ischemia in the rat brain was induced by middle cerebral artery occlusion. Human neural stem cells were transplanted into the subventricular zone. The behavioral performance of human neural stem cells-treated ischemic rats was significantly improved and cerebral infarct volumes were reduced compared to those in untreated animals. Numerous transplanted human neural stem cells were alive and preferentially localized to the ipsilateral ischemic hemisphere. Furthermore, 5-bromo-2′-deoxyuridine-labeled endogenous neural stem cells were observed in the subventricular zone and hippocampus, where they differentiated into cells immunoreactive for the neural markers doublecortin, neuronal nuclear antigen Neu N, and astrocyte marker glial fibrillary acidic protein in human neural stem cells-treated rats, but not in the untreated ischemic animals. The number of 5-bromo-2′-deoxyuridine-positive ？ anti-von Willebrand factor-positive proliferating endothelial cells was higher in the ischemic boundary zone of human neural stem cells-treated rats than in controls. Finally, transplantation of human neural stem cells in the brains of rats with focal cerebral ischemia promoted the proliferation of endogenous neural stem cells and their differentiation into mature neural-like cells, and enhanced angiogenesis. This study provides valuable insights into the effect of human neural stem cell transplantation on focal cerebral ischemia, which can be applied to the development of an effective therapy for stroke.展开更多
BACKGROUND： Many methods have been attempted to repair nerves following spinal cord injury, including peripheral nerve transplantation, Schwann cell transplantation, olfactory ensheathing cell transplantation, and em...BACKGROUND： Many methods have been attempted to repair nerves following spinal cord injury, including peripheral nerve transplantation, Schwann cell transplantation, olfactory ensheathing cell transplantation, and embryonic neural tissue transplantation. However, there is a need for improved outcomes. OBJECTIVE： To investigate the repair feasibility for rat spinal cord injury using human neural stem cells （hNSCs） genetically modified by lentivirus to express neurotrophin-3. DESIGN, TIME AND SETTING： In vitro cell biological experiment and in vivo randomized, controlled genetic engineering experiment were performed at the Third Military Medical University of Chinese PLA and First People＇s Hospital of Yibin, China from March 2006 to December 2007. MATERIALS： A total of 64 adult, female, Wistar rats were used for the in vivo study. Of them, 48 rats were used to establish models of spinal cord hemisection, and were subsequently equally and randomly assigned to model, genetically modified hNSC, and normal hNSC groups. The remaining 16 rats served as normal controls. METHODS： hNSCs were in vitro genetically modified by lentivirus to secrete both green fluorescence protein and neurotrophin-3. Neurotrophin-3 expression was measured by Western blot. Genetically modified hNSC or normal hNSC suspension （5 × 10^5） was injected into the rat spinal cord following T10 spinal cord hemisection. A total of 5μL Dulbecco＇s-modified Eagle＇s medium was infused into the rat spinal cord in the model grop. Transgene expression and survival of transplanted hNSCs were determined by immunohistochemistry. Motor function was evaluated using the Basso, Beattie, and Bresnahan （BBB） scale. MAIN OUTCOME MEASURES： The following parameters were measured： expression of neurotrophin-3 produced by genetically modified hNSCs, transgene expression and survival of hNSCs in rats, motor function in rats. RESULTS： hNSCs were successfully genetically modified by lentivirus to stably express neurotrophin-3. The transplanted hNSCs primarily gathered at, or around, the injection site two weeks following transplantation, and gradually migrated towards the surrounding tissue. Transplanted hNSCs were observed 7.0-8.0 mm away from the injection site. In addition, hNSCs were observed 10 weeks after transplantation. At week 4, BBB locomotor scores were significantly greater in the genetically modified hNSC and normal hNSC groups, compared with the model group （P 〈 0.05）, and scores were significantly greater in the genetically modified hNSC group compared with the normal hNSC group （P 〈 0.05）. CONCLUSION： hNSCs were genetically modified with lentivirus to stably secrete neurotrophin-3. hNSCs improved motor function recovery in rats following spinal cord injury.展开更多
BACKGROUND： Exogenous neural stem cell transplantation promotes neural regeneration. However, various types of stem cells transplantation outcomes remain controversial. OBJECTIVE： To explore distribution, proliferat...BACKGROUND： Exogenous neural stem cell transplantation promotes neural regeneration. However, various types of stem cells transplantation outcomes remain controversial. OBJECTIVE： To explore distribution, proliferation and differentiation of human neural stem cells （hNSCs） and human umbilical cord blood stem cells （hUCBSCs） following transplantation in ischemic brain tissue of rats, and to compare therapeutic outcomes between hNSCs and hUCBSCs. DESIGN, TIME AND SETTING： Randomized controlled animal studies were performed at the Experimental Animal Center of Nanjing Medical University and Central Laboratory of Second Affiliated Hospital of Nanjing Medical University of China from September 2008 to April 2009. MATERIALS： hNSCs were harvested from brain tissue of 10 13 week old fetuses following spontaneous abortion, and hUCBSCs were collected from umbilical cord blood of full-term newborns at the Second Affiliated Hospital of Nanjing Medical University of China. hNSCs and hUCBSCs were labeled by 5-bromodeoxyuridine （BrdU） prior to transplantation. METHODS： Rat models of cerebral ischemia were established by the suture method. A total of 60 healthy male Sprague Dawley rats aged 7-9 weeks were randomly assigned to hNSC transplantation, hUCBSC transplantation and control groups. The rat models in the hNSC transplantation, hUCBSC transplantation and control groups were infused with hNSC suspension, hUCBSC suspension and saline via the caudal vein, respectively. MAIN OUTCOME MEASURES： The distribution, proliferation and differentiation of hNSCs and hUCBSCs in ischemic brain tissue were observed using immunohistochemical methods. Neurological function in rats was assessed using the neurological severity score. RESULTS： The number of BrdU-positive cells was significantly greater in the hNSC transplantation group compared with hUCBSC transplantation group at 14 days following transplantation （P 〈 0.05） The number of BrdU-positive cells reached a peak at 28 days following transplantation. Nestin-positive, glial fibrillary acidic protein-positive, cyclic nucleotide 3＇ phosphohydrolase-positive and neuron specific enolase-positive cells were visible following transplantation. No significant difference was determined in the constituent ratio of various cells between hNSC and hUCBSC transplantation groups （P 〉 0.05）. The neurological severity score was significantly decreased in rats at 21 days following transplantation （P 〈 0.05）. No significant difference was detected in neurological severity score between hNSC and hUCBSC transplantation groups at various time points （P 〉 0.05）. CONCLUSION： The transplanted hNSCs and hUCBSCs can migrate into ischemic brain tissue, proliferate and differentiate into neuron-like, astrocyte-like and oligodendrocyte-like cells, and improve neurological function in rats with cerebral ischemia.展开更多
Human neural stem cells（h NSCs） derived from the ventral mesencephalon are powerful research tools and candidates for cell therapies in Parkinson＇s disease. However, their clinical translation has not been fully re...Human neural stem cells（h NSCs） derived from the ventral mesencephalon are powerful research tools and candidates for cell therapies in Parkinson＇s disease. However, their clinical translation has not been fully realized due, in part, to the limited ability to track stem cell regional localization and survival over long periods of time after in vivo transplantation. Magnetic resonance imaging provides an excellent non-invasive method to study the fate of transplanted cells in vivo. For magnetic resonance imaging cell tracking, cells need to be labeled with a contrast agent, such as magnetic nanoparticles, at a concentration high enough to be easily detected by magnetic resonance imaging. Grafting of human neural stem cells labeled with magnetic nanoparticles allows cell tracking by magnetic resonance imaging without impairment of cell survival, proliferation, self-renewal, and multipotency. However, the results reviewed here suggest that in long term grafting, activated microglia and macrophages could contribute to magnetic resonance imaging signal by engulfing dead labeled cells or iron nanoparticles dispersed freely in the brain parenchyma over time.展开更多
Background Since an effective method for generating induced pluripotent stem cells （iPSCs） from human neural stem cells （hNSCs） can offer us a promising tool for studying brain diseases, here we reported direct re...Background Since an effective method for generating induced pluripotent stem cells （iPSCs） from human neural stem cells （hNSCs） can offer us a promising tool for studying brain diseases, here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors. Methods NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients. When combined with four factors （OCT3/4, SOX2, KLF4, and c-MYC）, iPSCs colonies were successfully obtained. Results Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties, which include the ability to differentiate into all three germ layers both in vitro and in vivo. Conclusion Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.展开更多
Human neural stem cells（h NSCs） are a useful tool to assess the developmental effects of various environmental contaminants; however, the application of h NSCs to evaluate water disinfection byproducts（DBPs） is sc...Human neural stem cells（h NSCs） are a useful tool to assess the developmental effects of various environmental contaminants; however, the application of h NSCs to evaluate water disinfection byproducts（DBPs） is scarce. Comprehensive toxicological results are essential to the prioritization of DBPs for further testing and regulation. Therefore, this study examines the effects of DBPs on the proliferation and differentiation of h NSCs. Prior to DBP treatment, characteristic protein markers of h NSCs from passages 3 to 6 were carefully examined and it was determined that h NSCs passaged 3 or 4 times maintained stem cell characteristics and can be used for DBP analysis. Two regulated DBPs, monobromoacetic acid（BAA） and monochloroacetic acid（CAA）, and two emerging DBPs, 2,6-dibromo-1,4-benzoquinone（2,6-DBBQ） and 2,6-dichloro-1,4-benzoquinone（2,6-DCBQ）, were chosen for h NSC treatment. Both 2,6-DBBQ and 2,6-DCBQ induced cell cycle arrest at S-phase at concentrations up to 1 μmol/L. Comparatively, BAA and CAA at 0.5 μmol/L affected neural differentiation. These results suggest DBP-dependent effects on h NSC proliferation and differentiation. The DBP-induced cell cycle arrest and inhibition of normal h NSC differentiation demonstrate the need to assess the developmental neurotoxicity of DBPs.展开更多
New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct pro...New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct proliferation of many cell types,guided outgrowth of human neurites has been found difficult to achieve so far.Here,three-dimensional(3D)micropatterned carbon nanotube(CNT)templates are used to effectively direct human neurite stem cell growth.By exploiting the mechanical flexibility,electrically conductivity and texture of the 3D CNT micropillars,a perfect environment is created to achieve specific guidance of human neurites,which may lead to enhanced therapeutic effects within the injured spinal cord or peripheral nerves.It is found that the 3D CNT micropillars grant excellent anchoring for adjacent neurites to form seamless neuronal networks that can be grown to any arbitrary shape and size.Apart from clear practical relevance in regenerative medicine,these results using the CNT based templates on Si chips also can pave the road for new types of microelectrode arrays to study cell network electrophysiology.展开更多
Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural dif...Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.展开更多
Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit model...Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 10^6 human umbilical cord blood stem cells. After 30 days, the maximum load, maximum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neurotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These findings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, improve biomechanical properties, and contribute to the recovery after injury.展开更多
Given the anatomic complexity at the bifurcation point of a nerve trunk,enforced suturing between stumps can lead to misdirection of nerve axons,thereby resulting in adverse consequences.We assumed that Y-tube conduit...Given the anatomic complexity at the bifurcation point of a nerve trunk,enforced suturing between stumps can lead to misdirection of nerve axons,thereby resulting in adverse consequences.We assumed that Y-tube conduits injected with human umbilical cord stem cells could be an effective method to solve such problems,but studies focused on the best type of Y-tube conduit remain controversial.Therefore,the present study evaluated the applicability and efficacy of various types of Y-tube conduits containing human umbilical cord stem cells for treating rat femoral nerve defects on their bifurcation points.At 12 weeks after the bridging surgery that included treatment with different types of Y-tube conduits,there were no differences in quadriceps femoris muscle weight or femoral nerve ultrastructure.However,the Y-tube conduit group with longer branches and a short trunk resulted in a better outcome according to retrograde labeling and electrophysiological analysis.It can be concluded from the study that repairing a mixed nerve defect at its bifurcation point with Y-tube conduits,in particular those with long branches and a short trunk,is effective and results in good outcomes.展开更多
Continuous immunosuppression has been widely used in xenografts into non-human primate brains.However,how immune responses change after transplantation in host brains under continuous immunosuppressive adminis-tration...Continuous immunosuppression has been widely used in xenografts into non-human primate brains.However,how immune responses change after transplantation in host brains under continuous immunosuppressive adminis-tration and whether immunosuppression can be withdrawn to mitigate side effects remain unclear.Human induced neural stem/progenitor cells(iNPCs)have shown long-term survival and efficient neuronal differentiation in primate brains.Here,we evaluate the immune responses in primate brains triggered by human grafts.The results show that the immune responses,including the evident activation of microglia and the strong infiltration of lymphocytes(both T-and B-cells),are caused by xenografts at 4 months post transplantation(p.t.),but significantly reduced at 8 months p.t.under continuous administration of immunosuppressant Cyclosporin A.However,early immuno-suppressant withdrawal at 5 months p.t.results in severe immune responses at 10 months p.t.These results suggest that continuous long-term immunosuppression is required for suppressing immune responses to xenografts in pri-mate brains.展开更多
基金supported by the Korea Health Technology R&D Project,Ministry of Health & Welfare(HI12C0381),Republic of Korea
文摘Transplantation of human neural stem cells into the dentate gyrus or ventricle of rodents has been reportedly to enhance neurogenesis. In this study, we examined endogenous stem cell proliferation and angiogenesis in the ischemic rat brain after the transplantation of human neural stem cells. Focal cerebral ischemia in the rat brain was induced by middle cerebral artery occlusion. Human neural stem cells were transplanted into the subventricular zone. The behavioral performance of human neural stem cells-treated ischemic rats was significantly improved and cerebral infarct volumes were reduced compared to those in untreated animals. Numerous transplanted human neural stem cells were alive and preferentially localized to the ipsilateral ischemic hemisphere. Furthermore, 5-bromo-2′-deoxyuridine-labeled endogenous neural stem cells were observed in the subventricular zone and hippocampus, where they differentiated into cells immunoreactive for the neural markers doublecortin, neuronal nuclear antigen Neu N, and astrocyte marker glial fibrillary acidic protein in human neural stem cells-treated rats, but not in the untreated ischemic animals. The number of 5-bromo-2′-deoxyuridine-positive ？ anti-von Willebrand factor-positive proliferating endothelial cells was higher in the ischemic boundary zone of human neural stem cells-treated rats than in controls. Finally, transplantation of human neural stem cells in the brains of rats with focal cerebral ischemia promoted the proliferation of endogenous neural stem cells and their differentiation into mature neural-like cells, and enhanced angiogenesis. This study provides valuable insights into the effect of human neural stem cell transplantation on focal cerebral ischemia, which can be applied to the development of an effective therapy for stroke.
文摘BACKGROUND： Many methods have been attempted to repair nerves following spinal cord injury, including peripheral nerve transplantation, Schwann cell transplantation, olfactory ensheathing cell transplantation, and embryonic neural tissue transplantation. However, there is a need for improved outcomes. OBJECTIVE： To investigate the repair feasibility for rat spinal cord injury using human neural stem cells （hNSCs） genetically modified by lentivirus to express neurotrophin-3. DESIGN, TIME AND SETTING： In vitro cell biological experiment and in vivo randomized, controlled genetic engineering experiment were performed at the Third Military Medical University of Chinese PLA and First People＇s Hospital of Yibin, China from March 2006 to December 2007. MATERIALS： A total of 64 adult, female, Wistar rats were used for the in vivo study. Of them, 48 rats were used to establish models of spinal cord hemisection, and were subsequently equally and randomly assigned to model, genetically modified hNSC, and normal hNSC groups. The remaining 16 rats served as normal controls. METHODS： hNSCs were in vitro genetically modified by lentivirus to secrete both green fluorescence protein and neurotrophin-3. Neurotrophin-3 expression was measured by Western blot. Genetically modified hNSC or normal hNSC suspension （5 × 10^5） was injected into the rat spinal cord following T10 spinal cord hemisection. A total of 5μL Dulbecco＇s-modified Eagle＇s medium was infused into the rat spinal cord in the model grop. Transgene expression and survival of transplanted hNSCs were determined by immunohistochemistry. Motor function was evaluated using the Basso, Beattie, and Bresnahan （BBB） scale. MAIN OUTCOME MEASURES： The following parameters were measured： expression of neurotrophin-3 produced by genetically modified hNSCs, transgene expression and survival of hNSCs in rats, motor function in rats. RESULTS： hNSCs were successfully genetically modified by lentivirus to stably express neurotrophin-3. The transplanted hNSCs primarily gathered at, or around, the injection site two weeks following transplantation, and gradually migrated towards the surrounding tissue. Transplanted hNSCs were observed 7.0-8.0 mm away from the injection site. In addition, hNSCs were observed 10 weeks after transplantation. At week 4, BBB locomotor scores were significantly greater in the genetically modified hNSC and normal hNSC groups, compared with the model group （P 〈 0.05）, and scores were significantly greater in the genetically modified hNSC group compared with the normal hNSC group （P 〈 0.05）. CONCLUSION： hNSCs were genetically modified with lentivirus to stably secrete neurotrophin-3. hNSCs improved motor function recovery in rats following spinal cord injury.
文摘BACKGROUND： Exogenous neural stem cell transplantation promotes neural regeneration. However, various types of stem cells transplantation outcomes remain controversial. OBJECTIVE： To explore distribution, proliferation and differentiation of human neural stem cells （hNSCs） and human umbilical cord blood stem cells （hUCBSCs） following transplantation in ischemic brain tissue of rats, and to compare therapeutic outcomes between hNSCs and hUCBSCs. DESIGN, TIME AND SETTING： Randomized controlled animal studies were performed at the Experimental Animal Center of Nanjing Medical University and Central Laboratory of Second Affiliated Hospital of Nanjing Medical University of China from September 2008 to April 2009. MATERIALS： hNSCs were harvested from brain tissue of 10 13 week old fetuses following spontaneous abortion, and hUCBSCs were collected from umbilical cord blood of full-term newborns at the Second Affiliated Hospital of Nanjing Medical University of China. hNSCs and hUCBSCs were labeled by 5-bromodeoxyuridine （BrdU） prior to transplantation. METHODS： Rat models of cerebral ischemia were established by the suture method. A total of 60 healthy male Sprague Dawley rats aged 7-9 weeks were randomly assigned to hNSC transplantation, hUCBSC transplantation and control groups. The rat models in the hNSC transplantation, hUCBSC transplantation and control groups were infused with hNSC suspension, hUCBSC suspension and saline via the caudal vein, respectively. MAIN OUTCOME MEASURES： The distribution, proliferation and differentiation of hNSCs and hUCBSCs in ischemic brain tissue were observed using immunohistochemical methods. Neurological function in rats was assessed using the neurological severity score. RESULTS： The number of BrdU-positive cells was significantly greater in the hNSC transplantation group compared with hUCBSC transplantation group at 14 days following transplantation （P 〈 0.05） The number of BrdU-positive cells reached a peak at 28 days following transplantation. Nestin-positive, glial fibrillary acidic protein-positive, cyclic nucleotide 3＇ phosphohydrolase-positive and neuron specific enolase-positive cells were visible following transplantation. No significant difference was determined in the constituent ratio of various cells between hNSC and hUCBSC transplantation groups （P 〉 0.05）. The neurological severity score was significantly decreased in rats at 21 days following transplantation （P 〈 0.05）. No significant difference was detected in neurological severity score between hNSC and hUCBSC transplantation groups at various time points （P 〉 0.05）. CONCLUSION： The transplanted hNSCs and hUCBSCs can migrate into ischemic brain tissue, proliferate and differentiate into neuron-like, astrocyte-like and oligodendrocyte-like cells, and improve neurological function in rats with cerebral ischemia.
基金To AMS:Instituto de Salud Carlos-III(RETICS Ter Cel RD12/0019/0013)Comunidad Autónoma de Madrid(S2010-BMD-2336)+3 种基金MINECO(SAF2010-17167)the institutional grant of the Fundación Ramón Areces to the CBMSOTo MRG:Reina Sofia FoundationComunidad Autónoma Madrid(S2010-BMD-2460)
文摘Human neural stem cells（h NSCs） derived from the ventral mesencephalon are powerful research tools and candidates for cell therapies in Parkinson＇s disease. However, their clinical translation has not been fully realized due, in part, to the limited ability to track stem cell regional localization and survival over long periods of time after in vivo transplantation. Magnetic resonance imaging provides an excellent non-invasive method to study the fate of transplanted cells in vivo. For magnetic resonance imaging cell tracking, cells need to be labeled with a contrast agent, such as magnetic nanoparticles, at a concentration high enough to be easily detected by magnetic resonance imaging. Grafting of human neural stem cells labeled with magnetic nanoparticles allows cell tracking by magnetic resonance imaging without impairment of cell survival, proliferation, self-renewal, and multipotency. However, the results reviewed here suggest that in long term grafting, activated microglia and macrophages could contribute to magnetic resonance imaging signal by engulfing dead labeled cells or iron nanoparticles dispersed freely in the brain parenchyma over time.
基金This work was supported by grants from the Major State Basic Research Program （No. 2010CB945500, No. 2012CB966300, and No. 2009CB941100）, the National Natural Science Foundation of China （No. 81271003 and No. 81200936）, Shanghai Committee of Science and Technology （No. 08dj140053）, and 2011 Shanghai Medical College Young Scientist Fund of Fudan University （11L-24）.Acknowledgements： We are grateful to technicians CHEN Lu-ping, SHEN Yi-wen and TANG Qi-sheng in our lab for their kind assistance in animal preparation and cell culture. We also thank Dr. SHA Hong-ying for picture processing and helpful comments and suggestions.
文摘Background Since an effective method for generating induced pluripotent stem cells （iPSCs） from human neural stem cells （hNSCs） can offer us a promising tool for studying brain diseases, here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors. Methods NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients. When combined with four factors （OCT3/4, SOX2, KLF4, and c-MYC）, iPSCs colonies were successfully obtained. Results Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties, which include the ability to differentiate into all three germ layers both in vitro and in vivo. Conclusion Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.
基金supported by funding from the Natural Sciences and Engineering Research Council (NSERC) of Canada, Alberta Innovates-Energy and Environmental Solutions, and Alberta Health
文摘Human neural stem cells（h NSCs） are a useful tool to assess the developmental effects of various environmental contaminants; however, the application of h NSCs to evaluate water disinfection byproducts（DBPs） is scarce. Comprehensive toxicological results are essential to the prioritization of DBPs for further testing and regulation. Therefore, this study examines the effects of DBPs on the proliferation and differentiation of h NSCs. Prior to DBP treatment, characteristic protein markers of h NSCs from passages 3 to 6 were carefully examined and it was determined that h NSCs passaged 3 or 4 times maintained stem cell characteristics and can be used for DBP analysis. Two regulated DBPs, monobromoacetic acid（BAA） and monochloroacetic acid（CAA）, and two emerging DBPs, 2,6-dibromo-1,4-benzoquinone（2,6-DBBQ） and 2,6-dichloro-1,4-benzoquinone（2,6-DCBQ）, were chosen for h NSC treatment. Both 2,6-DBBQ and 2,6-DCBQ induced cell cycle arrest at S-phase at concentrations up to 1 μmol/L. Comparatively, BAA and CAA at 0.5 μmol/L affected neural differentiation. These results suggest DBP-dependent effects on h NSC proliferation and differentiation. The DBP-induced cell cycle arrest and inhibition of normal h NSC differentiation demonstrate the need to assess the developmental neurotoxicity of DBPs.
基金G.S.L.and L.Y-O.acknowledge the support from the Academy of Finland(Nos.320090,317437 and 286990,respectively)J.T.K.and T.J.acknowledge the support from the Finnish Cultural Foundation Pirkanmaa Regional Fund(No.50151501)+1 种基金the Central Fund(#00150312),respectively.S.N.,T.J.and M.K.acknowledge the support from the Academy of Finland(S.N.and T.J.No.312414 and M.K.No.312409)Business Finland(former Tekes,Human Spare Parts project).This work made use of the electron microscopy and clean-room facilities at the Centre of Microscopy and Nanotechnology,at the University of Oulu.The authors also acknowledge the Tampere Imaging Facility(TIF)and the Tampere CellTech Laboratories for their service.
文摘New strategies for spatially controlled growth of human neurons may provide viable solutions to treat and recover peripheral or spinal cord injuries.While topography cues are known to promote attachment and direct proliferation of many cell types,guided outgrowth of human neurites has been found difficult to achieve so far.Here,three-dimensional(3D)micropatterned carbon nanotube(CNT)templates are used to effectively direct human neurite stem cell growth.By exploiting the mechanical flexibility,electrically conductivity and texture of the 3D CNT micropillars,a perfect environment is created to achieve specific guidance of human neurites,which may lead to enhanced therapeutic effects within the injured spinal cord or peripheral nerves.It is found that the 3D CNT micropillars grant excellent anchoring for adjacent neurites to form seamless neuronal networks that can be grown to any arbitrary shape and size.Apart from clear practical relevance in regenerative medicine,these results using the CNT based templates on Si chips also can pave the road for new types of microelectrode arrays to study cell network electrophysiology.
基金supported by the National Natural Science Foundation of China,No.31340024
文摘Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.
基金supported by a grant from Science and Technology Development Program of Jilin Province of China,No.20110492
文摘Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 10^6 human umbilical cord blood stem cells. After 30 days, the maximum load, maximum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neurotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These findings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, improve biomechanical properties, and contribute to the recovery after injury.
基金funded by the National High Technology Research and Development Program of China ("863" Program,No.2012AA020905)the National Natural Science Foundation of China (No.81360194)the National Basic Research Program of China (973 program,No.2014CB542200)
文摘Given the anatomic complexity at the bifurcation point of a nerve trunk,enforced suturing between stumps can lead to misdirection of nerve axons,thereby resulting in adverse consequences.We assumed that Y-tube conduits injected with human umbilical cord stem cells could be an effective method to solve such problems,but studies focused on the best type of Y-tube conduit remain controversial.Therefore,the present study evaluated the applicability and efficacy of various types of Y-tube conduits containing human umbilical cord stem cells for treating rat femoral nerve defects on their bifurcation points.At 12 weeks after the bridging surgery that included treatment with different types of Y-tube conduits,there were no differences in quadriceps femoris muscle weight or femoral nerve ultrastructure.However,the Y-tube conduit group with longer branches and a short trunk resulted in a better outcome according to retrograde labeling and electrophysiological analysis.It can be concluded from the study that repairing a mixed nerve defect at its bifurcation point with Y-tube conduits,in particular those with long branches and a short trunk,is effective and results in good outcomes.
基金National Key Basic Research and Development Program of China(2019YFA0801402,2018YFA0107200,2018YFA0801402,2018YFA0800100)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16020501,XDA16020404)National Natural Science Foundation of China(32130030,31900454).
文摘Continuous immunosuppression has been widely used in xenografts into non-human primate brains.However,how immune responses change after transplantation in host brains under continuous immunosuppressive adminis-tration and whether immunosuppression can be withdrawn to mitigate side effects remain unclear.Human induced neural stem/progenitor cells(iNPCs)have shown long-term survival and efficient neuronal differentiation in primate brains.Here,we evaluate the immune responses in primate brains triggered by human grafts.The results show that the immune responses,including the evident activation of microglia and the strong infiltration of lymphocytes(both T-and B-cells),are caused by xenografts at 4 months post transplantation(p.t.),but significantly reduced at 8 months p.t.under continuous administration of immunosuppressant Cyclosporin A.However,early immuno-suppressant withdrawal at 5 months p.t.results in severe immune responses at 10 months p.t.These results suggest that continuous long-term immunosuppression is required for suppressing immune responses to xenografts in pri-mate brains.
