RUNXI is absolutely required for definitive hematopoiesis, but the function of RUNXlb/c, two isoforms of human RUNX1, is unclear. We established inducible RUNXlb/c-overexpressing human embryonic stem cell （hESC） lin...RUNXI is absolutely required for definitive hematopoiesis, but the function of RUNXlb/c, two isoforms of human RUNX1, is unclear. We established inducible RUNXlb/c-overexpressing human embryonic stem cell （hESC） lines, in which RUNXlb/c overexpression prevented the emergence of CD34＋ cells from early stage, thereby drastically reducing the production of hematopoi- etic stem/prognnitor cells. Simultaneously, the expression of hematopoiesis-related factors was downregulated. However, such blockage effect disappeared from day 6 in hESC/AGM-S3 ceU co-cultures, proving that the blockage occurred before the generation of hemogenic endothelial cells. This blockage was partially rescued by RepSox, an inhibitor of the transforming growth factor （TGF）-β signaling pathway, indicating a close relationship between RUNX1b/c and TGF-β pathway. Our results suggest a unique inhibitory function of RUNX1b/c in the development of early hematopoiesis and may aid further understanding of its biological function in normal and diseased models.展开更多
Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the co...Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the course of normal aging.Unfortunately,the body does not fully repair itself from this type of degeneration,resulting in impaired movement.Microfracture,an articular cartilage repair surgical technique,has been commonly used in the clinic to induce the repair of tissue at damage sites.Mesenchymal stem cells(MSC)have also been used as cell therapy to repair degenerated cartilage.However,the therapeutic outcomes of all these techniques vary in different patients depending on their age,health,lesion size and the extent of damage to the cartilage.The repairing tissues either form fibrocartilage or go into a hypertrophic stage,both of which do not reproduce the equivalent functionality of endogenous hyaline cartilage.One of the reasons for this is inefficient chondrogenesis by endogenous and exogenous MSC.Drugs that promote chondrogenesis could be used to induce self-repair of damaged cartilage as a non-invasive approach alone,or combined with other techniques to greatly assist the therapeutic outcomes.The recent development of human induced pluripotent stem cell(iPSCs),which are able to self-renew and differentiate into multiple cell types,provides a potentially valuable cell resource for drug screening in a“more relevant”cell type.Here we report a screening platform using human iPSCs in a multi-well plate format to identify compounds that could promote chondrogenesis.展开更多
Introduction: Diabetes mellitus (DM), a metabolic disorder, is known to be highly prevalent in people aged 40 - 60 years in developing countries whereas in developed countries, it mostly affects people above the age o...Introduction: Diabetes mellitus (DM), a metabolic disorder, is known to be highly prevalent in people aged 40 - 60 years in developing countries whereas in developed countries, it mostly affects people above the age of 60 years. It is of two types: DM type I, an autoimmune disorder that mostly onsets after an infection and DM type II that is commonly associated with obesity. Several treatments are available for the treatment of DM, but none has successfully cured diabetes. Nowadays, stem cell therapy is being investigated for use in the treatment of DM and has shown positive results. Case Report: Our study presented results of three diabetic patients who were treated with human embryonic stem cell (hESC) therapy. Following the therapy, blood glucose levels were reduced. An improvement was observed in eye sight, stamina, gait pattern endurance, mental focus ability and muscle strength. There was a reduction in secondary side effects of high blood sugar such as affectation of cardiac, kidneys, polyneuropathy, vision etc. No adverse events and teratoma formation were observed after the treatment. Conclusion: It was concluded that hESCs showed good therapeutic potential in the treatment of patients with diabetes.展开更多
Differentiated embryonic stem cells (ESC) can ameliorate lung inflammation and fibrosis in animal lung injury models;therefore, ESC, or their products, could be candidates for regenerative therapy for incurable lung d...Differentiated embryonic stem cells (ESC) can ameliorate lung inflammation and fibrosis in animal lung injury models;therefore, ESC, or their products, could be candidates for regenerative therapy for incurable lung diseases, such as idiopathic pulmonary fibrosis (IPF). In this study, we have investigated the paracrine effect of differentiated and undifferentiated human ESC on alveolar epithelial cell (AEC) wound repair. hESC line, SHEF-2 cells were differentiated with Activin treatment for 22 days in an embryoid body (EB) suspension culture. Conditioned media (CM) which contain cell secretory factors were collected at different time points of differentiation. CM were then tested onin vitro?wound repair model with human type II AEC line, A549 cells (AEC). Our study demonstrated that CM originated from undifferentiated hESC significantly inhibited AEC wound repair when compared to the control. Whereas, CM originated from Activin-directed hESC differentiated cell population demonstrated a differential reparative effect on AEC wound repair model. CM obtained from Day-11 of differentiation significantly enhanced AEC wound repair in comparison to CM collected from pre- and post-Day-11 of differentiation. Day-11 CM enhanced AEC wound repair through significant stimulation of cell migration and cell proliferation. RT-PCR and immunocytochemistry confirmed that Day-11 CM was originated form a mixed population of endodermal/mesodermal differentiated hESC. This report suggests a putative paracrine-mediated epithelial injury healing mechanism by hESC secreted products, which is valuable in the development of novel stem cell-based therapeutic strategies.展开更多
In order to develop a novel method of visualizing possible Ca2＋ signaling during the early differentiation of hESCs into cardi- omyocytes and avoid some of the inherent problems associated with using fluorescent repo...In order to develop a novel method of visualizing possible Ca2＋ signaling during the early differentiation of hESCs into cardi- omyocytes and avoid some of the inherent problems associated with using fluorescent reporters, we expressed the biolumines- cent Ca2＋ reporter, apo-aequorin, in HES2 cells and then reconstituted active holo-aequorin by incubation withf-coelenterazine. The temporal nature of the Ca2＋ signals generated by the holo-f-aequorin-expressing HES2 cells during the earliest stages of differentiation into cardiomyocytes was then investigated. Our data show that no endogenous Ca2＋ transients （generated by re- lease from intracellular stores） were detected in 1-12-day-old cardiospheres but transients were generated in cardiospheres following stimulation with KC1 or CaC12, indicating that holo-f-aequorin was functional in these cells. Furthermore, following the addition of exogenous ATP, an inositol trisphosphate receptor （IP3R） agonist, small Ca2＋transients were generated from day 1 onward. That ATP was inducing Ca2＋ release from functional IP3Rs was demonstrated by treatment with 2-APB, a known IP3R antagonist. In contrast, following treatment with caffeine, a ryanodine receptor （RyR） agonist, a minima/Ca2＋ response was observed at day 8 of differentiation only. Thus, our data indicate that unlike RyRs, IP3Rs are present and continually functional at these early stages of cardiomyocyte differentiation.展开更多
The mammalian brain is heterogeneous, containing billions of neurons and trillions of synapses forming vari- ous neural circuitries, through which sense, movement, thought, and emotion arise. The cellular heterogeneit...The mammalian brain is heterogeneous, containing billions of neurons and trillions of synapses forming vari- ous neural circuitries, through which sense, movement, thought, and emotion arise. The cellular heterogeneity of the brain has made it difficult to study the molecular logic of neural circuitry wiring, pruning, activation, and plasticity, until recently, transcriptome analyses with single cell resolution makes decoding of gene regulatory networks underlying aforementioned circuitry properties possible. Here we report success in per- forming both electrophysiological and whole-genome transcriptome analyses on single human neurons in culture. Using Weighted Gene Coexpression Network Analyses （WGCNA）, we identified gene clusters highly correlated with neuronal maturation judged by electrophysiological characteristics. A tight link between neu- ronal maturation and genes involved in ubiquitination and mitochondrial function was revealed. Moreover, we identified a list of candidate genes, which could potentially serve as biomarkers for neuronal maturation. Coupled electrophysiological recording and single cell transcriptome analysis will serve as powerful tools in the future to unveil molecular logics for neural circuitry functions.展开更多
目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在...目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在三维培养体系中可检测细胞的侵袭性及细胞与基质的相互作用。BMP4途径通过去除外源性成纤维细胞生长因子及提高氧含量均可促进BMP4诱导TB的分化。虽然hESC分化TB模型目前还存在一些争议,但是相关研究可为探讨人类胚胎的植入及胎盘的形成提供重要的理论依据。展开更多
基金This work was supported by the National Program on Key Basic Research Project of China （973 Program 2015CB964902）, the National Natural Science Foundation of China （NSFC H81170466 and H81370597）, and the CAMS Initiatives for Innovative Medicine （2016-12M-1-018） awarded to F.M.
文摘RUNXI is absolutely required for definitive hematopoiesis, but the function of RUNXlb/c, two isoforms of human RUNX1, is unclear. We established inducible RUNXlb/c-overexpressing human embryonic stem cell （hESC） lines, in which RUNXlb/c overexpression prevented the emergence of CD34＋ cells from early stage, thereby drastically reducing the production of hematopoi- etic stem/prognnitor cells. Simultaneously, the expression of hematopoiesis-related factors was downregulated. However, such blockage effect disappeared from day 6 in hESC/AGM-S3 ceU co-cultures, proving that the blockage occurred before the generation of hemogenic endothelial cells. This blockage was partially rescued by RepSox, an inhibitor of the transforming growth factor （TGF）-β signaling pathway, indicating a close relationship between RUNX1b/c and TGF-β pathway. Our results suggest a unique inhibitory function of RUNX1b/c in the development of early hematopoiesis and may aid further understanding of its biological function in normal and diseased models.
文摘Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the course of normal aging.Unfortunately,the body does not fully repair itself from this type of degeneration,resulting in impaired movement.Microfracture,an articular cartilage repair surgical technique,has been commonly used in the clinic to induce the repair of tissue at damage sites.Mesenchymal stem cells(MSC)have also been used as cell therapy to repair degenerated cartilage.However,the therapeutic outcomes of all these techniques vary in different patients depending on their age,health,lesion size and the extent of damage to the cartilage.The repairing tissues either form fibrocartilage or go into a hypertrophic stage,both of which do not reproduce the equivalent functionality of endogenous hyaline cartilage.One of the reasons for this is inefficient chondrogenesis by endogenous and exogenous MSC.Drugs that promote chondrogenesis could be used to induce self-repair of damaged cartilage as a non-invasive approach alone,or combined with other techniques to greatly assist the therapeutic outcomes.The recent development of human induced pluripotent stem cell(iPSCs),which are able to self-renew and differentiate into multiple cell types,provides a potentially valuable cell resource for drug screening in a“more relevant”cell type.Here we report a screening platform using human iPSCs in a multi-well plate format to identify compounds that could promote chondrogenesis.
文摘Introduction: Diabetes mellitus (DM), a metabolic disorder, is known to be highly prevalent in people aged 40 - 60 years in developing countries whereas in developed countries, it mostly affects people above the age of 60 years. It is of two types: DM type I, an autoimmune disorder that mostly onsets after an infection and DM type II that is commonly associated with obesity. Several treatments are available for the treatment of DM, but none has successfully cured diabetes. Nowadays, stem cell therapy is being investigated for use in the treatment of DM and has shown positive results. Case Report: Our study presented results of three diabetic patients who were treated with human embryonic stem cell (hESC) therapy. Following the therapy, blood glucose levels were reduced. An improvement was observed in eye sight, stamina, gait pattern endurance, mental focus ability and muscle strength. There was a reduction in secondary side effects of high blood sugar such as affectation of cardiac, kidneys, polyneuropathy, vision etc. No adverse events and teratoma formation were observed after the treatment. Conclusion: It was concluded that hESCs showed good therapeutic potential in the treatment of patients with diabetes.
文摘Differentiated embryonic stem cells (ESC) can ameliorate lung inflammation and fibrosis in animal lung injury models;therefore, ESC, or their products, could be candidates for regenerative therapy for incurable lung diseases, such as idiopathic pulmonary fibrosis (IPF). In this study, we have investigated the paracrine effect of differentiated and undifferentiated human ESC on alveolar epithelial cell (AEC) wound repair. hESC line, SHEF-2 cells were differentiated with Activin treatment for 22 days in an embryoid body (EB) suspension culture. Conditioned media (CM) which contain cell secretory factors were collected at different time points of differentiation. CM were then tested onin vitro?wound repair model with human type II AEC line, A549 cells (AEC). Our study demonstrated that CM originated from undifferentiated hESC significantly inhibited AEC wound repair when compared to the control. Whereas, CM originated from Activin-directed hESC differentiated cell population demonstrated a differential reparative effect on AEC wound repair model. CM obtained from Day-11 of differentiation significantly enhanced AEC wound repair in comparison to CM collected from pre- and post-Day-11 of differentiation. Day-11 CM enhanced AEC wound repair through significant stimulation of cell migration and cell proliferation. RT-PCR and immunocytochemistry confirmed that Day-11 CM was originated form a mixed population of endodermal/mesodermal differentiated hESC. This report suggests a putative paracrine-mediated epithelial injury healing mechanism by hESC secreted products, which is valuable in the development of novel stem cell-based therapeutic strategies.
基金supported by the Hong Kong Theme-based Research Scheme award(T13-706/11-1)the Hong Kong Research Grants Council(RGC)General Research Fund awards(662113,16101714,16100115)+2 种基金the ANR/RGC joint research scheme award(A-HKUST601/13)the Innovation and Technology Commission(ITCPD/17-9)supported by a Hong Kong University Grants Council post-graduate studentship(T13-706/11-11PG)
文摘In order to develop a novel method of visualizing possible Ca2＋ signaling during the early differentiation of hESCs into cardi- omyocytes and avoid some of the inherent problems associated with using fluorescent reporters, we expressed the biolumines- cent Ca2＋ reporter, apo-aequorin, in HES2 cells and then reconstituted active holo-aequorin by incubation withf-coelenterazine. The temporal nature of the Ca2＋ signals generated by the holo-f-aequorin-expressing HES2 cells during the earliest stages of differentiation into cardiomyocytes was then investigated. Our data show that no endogenous Ca2＋ transients （generated by re- lease from intracellular stores） were detected in 1-12-day-old cardiospheres but transients were generated in cardiospheres following stimulation with KC1 or CaC12, indicating that holo-f-aequorin was functional in these cells. Furthermore, following the addition of exogenous ATP, an inositol trisphosphate receptor （IP3R） agonist, small Ca2＋transients were generated from day 1 onward. That ATP was inducing Ca2＋ release from functional IP3Rs was demonstrated by treatment with 2-APB, a known IP3R antagonist. In contrast, following treatment with caffeine, a ryanodine receptor （RyR） agonist, a minima/Ca2＋ response was observed at day 8 of differentiation only. Thus, our data indicate that unlike RyRs, IP3Rs are present and continually functional at these early stages of cardiomyocyte differentiation.
基金The online version of this article （doi：10.1007/s13238-016-0247-8） contains supplementary material, which is available to authorized users.This work was supported by the National Basic Research Program （973 Program） （No. 2012CB966303）, the National Natural Science Foundation of China （Grant Nos. 81330030, 91319309, and 31271371）, the Science and Technology Department of Yunnan Province （Grant 2012HA013）, the Yunnan Basic Research Projects （Grant 2014FC004）, and the Doctoral Tutor of Education Department of Shanghai, China （Grant 20130072110021 ）, grants from NASAD： BRN ＆ BEHV RES FND 23072, NIH R21：IR21NS095184-01 and finally, a fellowship from China Scholarship Council to X. -Y.C.
文摘The mammalian brain is heterogeneous, containing billions of neurons and trillions of synapses forming vari- ous neural circuitries, through which sense, movement, thought, and emotion arise. The cellular heterogeneity of the brain has made it difficult to study the molecular logic of neural circuitry wiring, pruning, activation, and plasticity, until recently, transcriptome analyses with single cell resolution makes decoding of gene regulatory networks underlying aforementioned circuitry properties possible. Here we report success in per- forming both electrophysiological and whole-genome transcriptome analyses on single human neurons in culture. Using Weighted Gene Coexpression Network Analyses （WGCNA）, we identified gene clusters highly correlated with neuronal maturation judged by electrophysiological characteristics. A tight link between neu- ronal maturation and genes involved in ubiquitination and mitochondrial function was revealed. Moreover, we identified a list of candidate genes, which could potentially serve as biomarkers for neuronal maturation. Coupled electrophysiological recording and single cell transcriptome analysis will serve as powerful tools in the future to unveil molecular logics for neural circuitry functions.
文摘目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在三维培养体系中可检测细胞的侵袭性及细胞与基质的相互作用。BMP4途径通过去除外源性成纤维细胞生长因子及提高氧含量均可促进BMP4诱导TB的分化。虽然hESC分化TB模型目前还存在一些争议,但是相关研究可为探讨人类胚胎的植入及胎盘的形成提供重要的理论依据。
