While human induced pluripotent stem cells(hiPSCs)have promising applications in regenerative medicine,most of the hiPSC lines available today are not suitable for clinical applications due to contamination with nonhu...While human induced pluripotent stem cells(hiPSCs)have promising applications in regenerative medicine,most of the hiPSC lines available today are not suitable for clinical applications due to contamination with nonhuman materials,such as sialic acid,and potential pathogens from animal-product-containing cell culture systems.Although several xeno-free cell culture systems have been established recently,their use of human fibroblasts as feeders reduces the clinical potential of hiPSCs due to batch-to-batch variation in the feeders and time-consuming preparation processes.In this study,we have developed a xeno-free and feeder-cell-free human embryonic stem cell(hESC)/hiPSC culture system using human plasma and human placenta extracts.The system maintains the self-renewing capacity and pluripotency of hESCs for more than 40 passages.Human iPSCs were also derived from human dermal fibroblasts using this culture system by overexpressing three transcription factors—Oct4,Sox2 and Nanog.The culture system developed here is inexpensive and suitable for large scale production.展开更多
A83-01 is a selective inhibitor of the TGF-β type I receptor ALK,which inhibits the TGF-β-induced epithelial-to-mesenchymal transition（EMT） via the inhibition of Smad2 phosphorylation.Previous studies have showed ...A83-01 is a selective inhibitor of the TGF-β type I receptor ALK,which inhibits the TGF-β-induced epithelial-to-mesenchymal transition（EMT） via the inhibition of Smad2 phosphorylation.Previous studies have showed that A83-01 promoted somatic cellular reprogramming significantly.Male germline stem cells（mGSCs）,as an alternative resource of pluripotent stem cells derived adult testis,have promising valuable in clinic medicine and regeneration,however,the derivation of mGSCs was complex and difficult.What the role A83-01 plays in promoting the proliferation of mGSCs is still unknown.In this study,combined with A83-01 and knockout serum replacement（KSR） medium,we obtained a relatively feeder-and serum-free system for mGSCs culturing in vitro and the optimal concentration of A83-01 was 0.25 μmol L-1.After continuous culturing,the proliferation efficiency of undifferentiated mGSCs and differentiation capacity of mGSC were examined as well.Results showed that,A83-01 dramatically increased the number of mGSCs and AP positive colonies,and the mitosis index according to the BrdU assay.A83-01 could also increase the expression of pluripotent markers including Oct4,Klf4,Nanog and c-Myc,analyzed byreal-time quantative PCR.mGSCs cultured in the optimal feeder-and serum-free system combined with A83-01 could form embryoid bodies（EBs）,which consisted of three embryonic layers detected by immunofluorescence and RT-PCR.Remarkably,the results demonstrated 0.25 μmol L-1A83-01 could promote the proliferation of mouse mGSC colonies and maintain their undifferentiated status under feeder-and serum-free systems.展开更多
鸡胚胎干细胞(cES)以其全能性,在研究胚胎发育生物学和家禽育种等方面有巨大的应用前景。本实验旨在建立cES无饲养层培养体系和对LipofactiminTMLTX(脂质体)介导转染体系进行优化。采用药匙法从新鲜受精蛋中分离获取cES,接种于层粘连蛋...鸡胚胎干细胞(cES)以其全能性,在研究胚胎发育生物学和家禽育种等方面有巨大的应用前景。本实验旨在建立cES无饲养层培养体系和对LipofactiminTMLTX(脂质体)介导转染体系进行优化。采用药匙法从新鲜受精蛋中分离获取cES,接种于层粘连蛋白包被的培养皿,待形成大克隆后,用口吸管剥离法吸取cES克隆进行消化传代,并采用生化和免疫学方法鉴定其干细胞活性。设计质粒量800、900、1 000 ng 3个水平,质粒、脂质体比为1∶1.5、1∶2、1∶2.5体系转染cES。结果表明:无饲养层培养体系体外培养cES细胞能稳定传代至第6代,鉴定结果显示碱性磷酸酶阳性和阶段特异性胚胎抗原1阳性,指明克隆能保持未分化状态;质粒900 ng、质脂比为1∶2时,可获得最佳转染效率72%,为cES的脂质体介导外源基因的转染提供参考。展开更多
Matrigel is routinely used as a coating material in the feeder-free culture system of human embryonic stem cells (hESCs). However, matrigel is costive and inconvenient to use. In this study, the possibility of using g...Matrigel is routinely used as a coating material in the feeder-free culture system of human embryonic stem cells (hESCs). However, matrigel is costive and inconvenient to use. In this study, the possibility of using gelatin as an alternative coating material was investigated. The results showed that, after trypsinization, hESCs were maintained undifferentiated on gelatin. These hESCs expressed pluripotent markers, formed teratoma and maintained a normal karyotype. As measured at passage 10, the hESCs expressed a high level of Oct4 on both gelatin and Matrigel. hESCs growing on gelatin formed AP-positive colonies in similar size and number to those growing on Matrigel (P > 0.05). Moreover, hESCs growing on gelatin contained a comparable percentage of SSEA-4-positive cells to those growing on Matrigel (95.1% vs.94.3%, P > 0.05). H-1 hESCs were maintained undifferentiated on gelatin for 20 passages and remained the stable normal karyotype. This gelatin-based culture protocol may allow us to propagate hESCs in large scale, with less cost.展开更多
基金by the National High Technology Research and Development Program(863 ProgramGrant No.2006AA02A106)+3 种基金the National Basic Research Program(973 ProgramGrant Nos.2006CB943901,2010CB945024,and 2011CB965002)the Knowledge Innovation Program of the Chinese Academy of Sciences(KSCX2-YW-R-50)the National Foundation of Science and Technology(No.30640005).
文摘While human induced pluripotent stem cells(hiPSCs)have promising applications in regenerative medicine,most of the hiPSC lines available today are not suitable for clinical applications due to contamination with nonhuman materials,such as sialic acid,and potential pathogens from animal-product-containing cell culture systems.Although several xeno-free cell culture systems have been established recently,their use of human fibroblasts as feeders reduces the clinical potential of hiPSCs due to batch-to-batch variation in the feeders and time-consuming preparation processes.In this study,we have developed a xeno-free and feeder-cell-free human embryonic stem cell(hESC)/hiPSC culture system using human plasma and human placenta extracts.The system maintains the self-renewing capacity and pluripotency of hESCs for more than 40 passages.Human iPSCs were also derived from human dermal fibroblasts using this culture system by overexpressing three transcription factors—Oct4,Sox2 and Nanog.The culture system developed here is inexpensive and suitable for large scale production.
基金supported by grants from the National Natural Science Foundation of China, China (30972097, 31272518)the Program for New Century Excellent Talents in University, China (NCET-09-0654)the Fundamental Research Funds for the Central Universities, China (QN2011012)
文摘A83-01 is a selective inhibitor of the TGF-β type I receptor ALK,which inhibits the TGF-β-induced epithelial-to-mesenchymal transition（EMT） via the inhibition of Smad2 phosphorylation.Previous studies have showed that A83-01 promoted somatic cellular reprogramming significantly.Male germline stem cells（mGSCs）,as an alternative resource of pluripotent stem cells derived adult testis,have promising valuable in clinic medicine and regeneration,however,the derivation of mGSCs was complex and difficult.What the role A83-01 plays in promoting the proliferation of mGSCs is still unknown.In this study,combined with A83-01 and knockout serum replacement（KSR） medium,we obtained a relatively feeder-and serum-free system for mGSCs culturing in vitro and the optimal concentration of A83-01 was 0.25 μmol L-1.After continuous culturing,the proliferation efficiency of undifferentiated mGSCs and differentiation capacity of mGSC were examined as well.Results showed that,A83-01 dramatically increased the number of mGSCs and AP positive colonies,and the mitosis index according to the BrdU assay.A83-01 could also increase the expression of pluripotent markers including Oct4,Klf4,Nanog and c-Myc,analyzed byreal-time quantative PCR.mGSCs cultured in the optimal feeder-and serum-free system combined with A83-01 could form embryoid bodies（EBs）,which consisted of three embryonic layers detected by immunofluorescence and RT-PCR.Remarkably,the results demonstrated 0.25 μmol L-1A83-01 could promote the proliferation of mouse mGSC colonies and maintain their undifferentiated status under feeder-and serum-free systems.
文摘鸡胚胎干细胞(cES)以其全能性,在研究胚胎发育生物学和家禽育种等方面有巨大的应用前景。本实验旨在建立cES无饲养层培养体系和对LipofactiminTMLTX(脂质体)介导转染体系进行优化。采用药匙法从新鲜受精蛋中分离获取cES,接种于层粘连蛋白包被的培养皿,待形成大克隆后,用口吸管剥离法吸取cES克隆进行消化传代,并采用生化和免疫学方法鉴定其干细胞活性。设计质粒量800、900、1 000 ng 3个水平,质粒、脂质体比为1∶1.5、1∶2、1∶2.5体系转染cES。结果表明:无饲养层培养体系体外培养cES细胞能稳定传代至第6代,鉴定结果显示碱性磷酸酶阳性和阶段特异性胚胎抗原1阳性,指明克隆能保持未分化状态;质粒900 ng、质脂比为1∶2时,可获得最佳转染效率72%,为cES的脂质体介导外源基因的转染提供参考。
基金Supported by the National Key Basic Research and Development of China (Grant Nos. 2006CB943603 and 2006CB503905)International Collaboration, the Ministry of Science and Technology of China (Grant No. 20070192)
文摘Matrigel is routinely used as a coating material in the feeder-free culture system of human embryonic stem cells (hESCs). However, matrigel is costive and inconvenient to use. In this study, the possibility of using gelatin as an alternative coating material was investigated. The results showed that, after trypsinization, hESCs were maintained undifferentiated on gelatin. These hESCs expressed pluripotent markers, formed teratoma and maintained a normal karyotype. As measured at passage 10, the hESCs expressed a high level of Oct4 on both gelatin and Matrigel. hESCs growing on gelatin formed AP-positive colonies in similar size and number to those growing on Matrigel (P > 0.05). Moreover, hESCs growing on gelatin contained a comparable percentage of SSEA-4-positive cells to those growing on Matrigel (95.1% vs.94.3%, P > 0.05). H-1 hESCs were maintained undifferentiated on gelatin for 20 passages and remained the stable normal karyotype. This gelatin-based culture protocol may allow us to propagate hESCs in large scale, with less cost.
