A paracrine regulation was recently proposed in human embryonic stem cells （hESCs） grown in mouse embryonic fibroblast （MEF）-conditioned media （MEF-CM）, where hESCs spontaneously differentiate into autologous fi...A paracrine regulation was recently proposed in human embryonic stem cells （hESCs） grown in mouse embryonic fibroblast （MEF）-conditioned media （MEF-CM）, where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI （IGF-Ⅱ） in response to basic fibroblast growth factor （bFGF）. Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought （i） to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts （HFFs） and human mesenchymal stem cells （hM- SCs） rather than MEF-CM, and （ii） to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell （MSC）-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors （FGFR1-4） and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.展开更多
The pluripotent state between human and mouse embryonic stem cells is different.Pluripotent state of human embryonic stem cells(ESCs)is believed to be primed and is similar with that of mouse epiblast stem cells(EpiSC...The pluripotent state between human and mouse embryonic stem cells is different.Pluripotent state of human embryonic stem cells(ESCs)is believed to be primed and is similar with that of mouse epiblast stem cells(EpiSCs),which is different from the naïve state of mouse ESCs.Human ESCs could be converted into a naïve state through exogenous expression of defined transcription factors(Hanna et al.,2010).Here we report a rapid conversion of human ESCs to mouse ESC-like naïve states only by modifying the culture conditions.These converted human ESCs,which we called mhESCs(mouse ESC-like human ESCs),have normal karyotype,allow single cell passage,exhibit domed morphology like mouse ESCs and express some pluripotent markers similar with mouse ESCs.Thus the rapid conversion established a naïve pluripotency in human ESCs like mouse ESCs,and provided a new model to study the regulation of pluripotency.展开更多
Clinical therapies of pluripotent stem cells （PSCs）-based transplantation have been hindered by frequent development of terato- mas or tumors in animal models and clinical patients. Therefore, clarifying the mechani...Clinical therapies of pluripotent stem cells （PSCs）-based transplantation have been hindered by frequent development of terato- mas or tumors in animal models and clinical patients. Therefore, clarifying the mechanism of carcinogenesis in stem cell therapy is of great importance for reducing the risk of tumorigenicity. Here we differentiate Oct4-GFP mouse embryonic stem cells （mESCs） into neural progenitor cells （NPCs） and find that a minority of Oct4＋ cells are continuously sustained at Oct4＋ state. These cells can be enriched and proliferated in a standard ESC medium. Interestingly, the differentiation potential of these enriched cells is tightly restricted with much higher tumorigenic activity, which are thus defined as differentiation-resistant ESCs （DR-ESCs）. Transcriptomic and epigenomic analyses show that DR-ESCs are characterized by primordial germ cell-like gene sig- natures （Dazl, Rec8, Stro8, BUmp1, etc.） and specific epigenetic patterns distinct from mESCs. Moreover, the DR-ESCs possess germ cell potential to generate Sycp3＋ haploid cells and are able to reside in sperm-free spermaduct induced by busulfan. Finally, we find that TGFβ signaling is overactivated in DR-ESCs, and inhibition of TGFβ signaling eliminates the tumorigenicity of mESC-derived NPCs by inducing the full differentiation of DR-ESCs. These data demonstrate that these TGFβ-hyperactivated germ ceU-like DR-ESCs are the main contributor for the tumorigenicity of ESCs-derived target cell therapy and that inhibition of TGFβ signaling in ESC-derived NPC transplantation could drastically reduce the risk of tumor development. Keywords： embryonic stem cells, differentiation-resistant ESCs, tumorigenicity, germ cell, TGFβ signaling展开更多
为探讨家庭社会经济文化地位(Economic, Social and Cultural Status,以下简称ESCS)对青少年幸福感的内在影响机制。采用国际学生评价估项目(Programmer for International Student Assessment,以下简称PISA)2018年测评数据构建结构方...为探讨家庭社会经济文化地位(Economic, Social and Cultural Status,以下简称ESCS)对青少年幸福感的内在影响机制。采用国际学生评价估项目(Programmer for International Student Assessment,以下简称PISA)2018年测评数据构建结构方程模型进行分析。研究结果表明,ESCS可以正向预测青少年幸福感;学业成就在ESCS与幸福感之间起部分中介作用;青少年核心自我评价调节了ESCS通过学业成就影响青少年幸福感的中介过程。结论:ESCS对幸福感的影响是一个有调节的中介过程,ESCS可以直接影响幸福感,也可以通过阅读学业成就影响幸福感;核心自我评价可以调节ESCS影响青少年幸福感的过程。展开更多
随着近年来一系列心力衰竭(心衰)诊治的相关循证医学证据及临床实践经验的不断积累,欧洲心脏病学会(European Society of Cardiology,ESC)和ESC心力衰竭协会于2023年公布了针对《2021 ESC急慢性心力衰竭诊断和治疗指南》(简称2021年版指...随着近年来一系列心力衰竭(心衰)诊治的相关循证医学证据及临床实践经验的不断积累,欧洲心脏病学会(European Society of Cardiology,ESC)和ESC心力衰竭协会于2023年公布了针对《2021 ESC急慢性心力衰竭诊断和治疗指南》(简称2021年版指南)的更新[1]。该更新指南针对慢性心衰的分类依然沿用2021年版指南分类:射血分数降低的心衰(heart failure with reduced ejection fraction,HFrEF)、中间范围射血分数心衰(heart failure with mid-range ejection fraction,HFmrEF)和射血分数保留的心衰(heart failure with preserved ejection fraction,HFpEF)。本次指南更新主要集中于HFmrEF和HFpEF患者的药物治疗和管理、急性心衰治疗策略和心衰并发症的治疗。现对其重要推荐更新进行解读。展开更多
文摘A paracrine regulation was recently proposed in human embryonic stem cells （hESCs） grown in mouse embryonic fibroblast （MEF）-conditioned media （MEF-CM）, where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI （IGF-Ⅱ） in response to basic fibroblast growth factor （bFGF）. Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought （i） to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts （HFFs） and human mesenchymal stem cells （hM- SCs） rather than MEF-CM, and （ii） to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell （MSC）-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors （FGFR1-4） and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.
基金by grants from the China National Basic Research Program(Grant No.2011CB965300)to L.W.grants from the National Natural Science Foundation of China(Grant No.90919060)to Q.Z.grants from the"Strategic Priority Research Program"of the Chinese Academy of Sciences(No.XDA01020101)to Q.Z.
文摘The pluripotent state between human and mouse embryonic stem cells is different.Pluripotent state of human embryonic stem cells(ESCs)is believed to be primed and is similar with that of mouse epiblast stem cells(EpiSCs),which is different from the naïve state of mouse ESCs.Human ESCs could be converted into a naïve state through exogenous expression of defined transcription factors(Hanna et al.,2010).Here we report a rapid conversion of human ESCs to mouse ESC-like naïve states only by modifying the culture conditions.These converted human ESCs,which we called mhESCs(mouse ESC-like human ESCs),have normal karyotype,allow single cell passage,exhibit domed morphology like mouse ESCs and express some pluripotent markers similar with mouse ESCs.Thus the rapid conversion established a naïve pluripotency in human ESCs like mouse ESCs,and provided a new model to study the regulation of pluripotency.
基金This work was supported in part by the Hundred Talent Program of Guangzhou University and the National Natural Science Foundation of China （31501178）, as well as by the ＇Strategic Priority Research Program＇ of the Chinese Academy of Sciences （XDA16020501 and XDA16020404）, the National Key Basic Research and Development Program of China （2017YFA0102700, 2015CB964500, and 2014CB964804）, and the National Natural Science Foundation of China （31661143042, 91519314, 31630043, 31571513, and 31430058）.
文摘Clinical therapies of pluripotent stem cells （PSCs）-based transplantation have been hindered by frequent development of terato- mas or tumors in animal models and clinical patients. Therefore, clarifying the mechanism of carcinogenesis in stem cell therapy is of great importance for reducing the risk of tumorigenicity. Here we differentiate Oct4-GFP mouse embryonic stem cells （mESCs） into neural progenitor cells （NPCs） and find that a minority of Oct4＋ cells are continuously sustained at Oct4＋ state. These cells can be enriched and proliferated in a standard ESC medium. Interestingly, the differentiation potential of these enriched cells is tightly restricted with much higher tumorigenic activity, which are thus defined as differentiation-resistant ESCs （DR-ESCs）. Transcriptomic and epigenomic analyses show that DR-ESCs are characterized by primordial germ cell-like gene sig- natures （Dazl, Rec8, Stro8, BUmp1, etc.） and specific epigenetic patterns distinct from mESCs. Moreover, the DR-ESCs possess germ cell potential to generate Sycp3＋ haploid cells and are able to reside in sperm-free spermaduct induced by busulfan. Finally, we find that TGFβ signaling is overactivated in DR-ESCs, and inhibition of TGFβ signaling eliminates the tumorigenicity of mESC-derived NPCs by inducing the full differentiation of DR-ESCs. These data demonstrate that these TGFβ-hyperactivated germ ceU-like DR-ESCs are the main contributor for the tumorigenicity of ESCs-derived target cell therapy and that inhibition of TGFβ signaling in ESC-derived NPC transplantation could drastically reduce the risk of tumor development. Keywords： embryonic stem cells, differentiation-resistant ESCs, tumorigenicity, germ cell, TGFβ signaling
文摘为探讨家庭社会经济文化地位(Economic, Social and Cultural Status,以下简称ESCS)对青少年幸福感的内在影响机制。采用国际学生评价估项目(Programmer for International Student Assessment,以下简称PISA)2018年测评数据构建结构方程模型进行分析。研究结果表明,ESCS可以正向预测青少年幸福感;学业成就在ESCS与幸福感之间起部分中介作用;青少年核心自我评价调节了ESCS通过学业成就影响青少年幸福感的中介过程。结论:ESCS对幸福感的影响是一个有调节的中介过程,ESCS可以直接影响幸福感,也可以通过阅读学业成就影响幸福感;核心自我评价可以调节ESCS影响青少年幸福感的过程。
文摘随着近年来一系列心力衰竭(心衰)诊治的相关循证医学证据及临床实践经验的不断积累,欧洲心脏病学会(European Society of Cardiology,ESC)和ESC心力衰竭协会于2023年公布了针对《2021 ESC急慢性心力衰竭诊断和治疗指南》(简称2021年版指南)的更新[1]。该更新指南针对慢性心衰的分类依然沿用2021年版指南分类:射血分数降低的心衰(heart failure with reduced ejection fraction,HFrEF)、中间范围射血分数心衰(heart failure with mid-range ejection fraction,HFmrEF)和射血分数保留的心衰(heart failure with preserved ejection fraction,HFpEF)。本次指南更新主要集中于HFmrEF和HFpEF患者的药物治疗和管理、急性心衰治疗策略和心衰并发症的治疗。现对其重要推荐更新进行解读。
