Human pluripotent stem cells represent a potentially unlimited source of functional pancreatic endocrine lineage cells. Here we report a highly efficient approach to induce human embryonic stem （ES） cells and induce...Human pluripotent stem cells represent a potentially unlimited source of functional pancreatic endocrine lineage cells. Here we report a highly efficient approach to induce human embryonic stem （ES） cells and induced pluripo- tent stem （iPS） cells to differentiate into mature insulin-producing cells in a chemical-defined culture system. The differentiated human ES cells obtained by this approach comprised nearly 25% insulin-positive cells as assayed by flow cytometry analysis, which released insulin/C-peptide in response to glucose stimuli in a manner comparable to that of adult human islets. Most of these insulin-producing cells co-expressed mature β cell-specific markers such as NKX6-1 and PDX1, indicating a similar gene expression pattern to adult islet β cells in vivo. In this study, we also demonstrated that EGF facilitates the expansion of PDXl-positive pancreatic progenitors. Moreover, our protocol also succeeded in efficiently inducing human iPS cells to differentiate into insuIin-producing ceils. Therefore, this work not only provides a new model to study the mechanism of human pancreatic specialization and maturation in vitro, but also enhances the possibility of utilizing patient-specific iPS cells for the treatment of diabetes.展开更多
The capacity for self-renewal and differentiation of human embryonic stem （ES） cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a new...The capacity for self-renewal and differentiation of human embryonic stem （ES） cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a newly developed and effective method, carried out in a serum-free system, which induced human ES cells to differentiate into insulin-producing cells. Activin A was used in the initial stage to induce definitive endoderm differentiation from human ES cells, as detected by the expression of the definitive endoderm markers Sox17 and Brachyury. Further, all-trans retinoic acid （RA） was used to promote pancreatic differentiation, as indicated by the expression of the early pancreatic transcription factors pdxl and hlxb9. After maturation in DMEM/F12 serum-free medium with bFGF and nicotinamide, the differentiated cells expressed islet specific markers such as C-peptide, insulin, glucagon and glut2. The percentage of C-peptide-positive cells exceeded 15%. The secretion of insulin and C-peptide by these cells corresponded to the variations in glucose levels. When transplanted into renal capsules of Streptozotocin （STZ）-treated nude mice, these differentiated human ES cells survived and maintained the expression of beta cell marker genes, including C-peptide, pdxl, glucokinase, nkx6.1, lAPP, pax6 and Tcfl. Thirty percent of the transplanted nude mice exhibited apparent restoration of stable euglycemia; and the corrected phenotype was sustained for more than six weeks. Our new method provides a promising in vitro differentiation model for studying the mechanisms of human pancreas development and illustrates the potential of using human ES cells for the treatment of type I diabetes mellitus.展开更多
Regenerative medicine, including cell-replacement strategies, may have an important role in the treatment of type 1 diabetes which is associated with decreased islet cell mass. To date, significant progress has been m...Regenerative medicine, including cell-replacement strategies, may have an important role in the treatment of type 1 diabetes which is associated with decreased islet cell mass. To date, significant progress has been made in generating insulin-secreting 13 cells from pluripotent mouse embryonic stem cells （ESCs）.The aim of this study is to explore the potential of regulating the differentiation of ESCs into pancreatic endocrine cells capable of synthesizing the pancreatic hormones including insulin, glucagon, somatostatin and pancreatic polypeptide under proper conditions. Undifferentiated ES cell line was stably transfected with mouse RIP-YFP plasmid construction in serum-free medium using LipofectamineTM 2000 Reagents. We tested pancreatic specific gene expression and characterized these ESC-derived pancreatic endocrine cells. Most of these insulin-secreting cells co-expressed many of the phenotypic markers characteristic of 13 cells such as insulinl, insulin2, Isletl, MafA, insulinoma-associated antigen 1 （IA1） and so on, indicating a similar gene expression pattern to adult islet 13 cells in vivo. Characterization of this population revealed that it consisted predominantly of pancreatic endocrine cells that were able to undergo pancreatic specification under the appropriate conditions. We also demonstrated that zinc supplementation mediated up-regulation of insulin-secreting cells as an effective inducer promoted the development of ESC-derived diabetes therapy. In conclusion, this work not only established an efficient pancreatic differentiation strategy from ESCs to pancreatic endocrine lineage in vitro, but also leaded to the development of new strategies to derive transplantable islet-replacement 13 cells from embryonic stem cells for the future applications of a stem cell based therapy of diabetes.展开更多
The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines （GF-CYK）： insulin-like growth factorl （IGF-Ⅰ）, insulin-like growth f...The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines （GF-CYK）： insulin-like growth factorl （IGF-Ⅰ）, insulin-like growth factorⅡ （IGF-Ⅱ）, basic fibroblast growth factor （bFGF）, leukemia inhibitory factor （LIF）, granulocyte-macrophage colony stimulating factor （GM-CSF） and transforming growth factor beta Ⅰ （TGF-β1） ＋ hyaluronan （HA） ＋ recombinant albumin （RA）. The embryos were cultured in synthetic oviduct fluid （SOF） supplemented with： treatment 1 （T1）： bovine serum albumin （BSA） ＋ insulin, transferrin and selenium （ITS） （control）; or treatment 2 （T2）： GF-CYK ＋ HA ＋ RA. The blastocyst rates were not significantly different between TI and T2, at seven days post fertilization （dpf） （28.9% ± 2.4% and 31.8% ±2.2%）, and at 8 dpf （36.5% ±2.4% and 39.1% ±1.9%）, respectively （P 〉 0.05）. The total cell number （TCN） was significantly higher with T2 than that with T1 at 7 dpf（164.9 ±5.3 and 149.7 ±4.0） and 8 dpf （182.7 ±6.4 and 165.0 ±5.5） （P 〈 0.05）. The blastocyst diameter obtained with T2 was significantly greater （P 〈 0.05） than with T1 at 7 dpf （173.3 μm ±4.9 μm and 157.2μm ±4.1 μm, respectively）, however, no significant differences were observed at 8 dpf （190.3 μm 5.2 μm and 179.7 μm ± 5.3 μm, respectively）. In conclusion, the synthetic medium （T2） shows a comparable development rate to the control medium and improves the blastocyst diameter and the TCN.展开更多
文摘Human pluripotent stem cells represent a potentially unlimited source of functional pancreatic endocrine lineage cells. Here we report a highly efficient approach to induce human embryonic stem （ES） cells and induced pluripo- tent stem （iPS） cells to differentiate into mature insulin-producing cells in a chemical-defined culture system. The differentiated human ES cells obtained by this approach comprised nearly 25% insulin-positive cells as assayed by flow cytometry analysis, which released insulin/C-peptide in response to glucose stimuli in a manner comparable to that of adult human islets. Most of these insulin-producing cells co-expressed mature β cell-specific markers such as NKX6-1 and PDX1, indicating a similar gene expression pattern to adult islet β cells in vivo. In this study, we also demonstrated that EGF facilitates the expansion of PDXl-positive pancreatic progenitors. Moreover, our protocol also succeeded in efficiently inducing human iPS cells to differentiate into insuIin-producing ceils. Therefore, this work not only provides a new model to study the mechanism of human pancreatic specialization and maturation in vitro, but also enhances the possibility of utilizing patient-specific iPS cells for the treatment of diabetes.
基金This research was supported by the Ministry of Science and Technology Grant （2001CB510106）；Science and Technology Plan of Beijing Municipal Government （H020220050290）；National Natural Science Foundation of China Awards for 0utstanding Young Scientists （30125022）；for Creative Research Groups （30421004）；Bill ＆ Melinda Gates Foundation Grant （37871） to H Deng.
文摘The capacity for self-renewal and differentiation of human embryonic stem （ES） cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a newly developed and effective method, carried out in a serum-free system, which induced human ES cells to differentiate into insulin-producing cells. Activin A was used in the initial stage to induce definitive endoderm differentiation from human ES cells, as detected by the expression of the definitive endoderm markers Sox17 and Brachyury. Further, all-trans retinoic acid （RA） was used to promote pancreatic differentiation, as indicated by the expression of the early pancreatic transcription factors pdxl and hlxb9. After maturation in DMEM/F12 serum-free medium with bFGF and nicotinamide, the differentiated cells expressed islet specific markers such as C-peptide, insulin, glucagon and glut2. The percentage of C-peptide-positive cells exceeded 15%. The secretion of insulin and C-peptide by these cells corresponded to the variations in glucose levels. When transplanted into renal capsules of Streptozotocin （STZ）-treated nude mice, these differentiated human ES cells survived and maintained the expression of beta cell marker genes, including C-peptide, pdxl, glucokinase, nkx6.1, lAPP, pax6 and Tcfl. Thirty percent of the transplanted nude mice exhibited apparent restoration of stable euglycemia; and the corrected phenotype was sustained for more than six weeks. Our new method provides a promising in vitro differentiation model for studying the mechanisms of human pancreas development and illustrates the potential of using human ES cells for the treatment of type I diabetes mellitus.
文摘Regenerative medicine, including cell-replacement strategies, may have an important role in the treatment of type 1 diabetes which is associated with decreased islet cell mass. To date, significant progress has been made in generating insulin-secreting 13 cells from pluripotent mouse embryonic stem cells （ESCs）.The aim of this study is to explore the potential of regulating the differentiation of ESCs into pancreatic endocrine cells capable of synthesizing the pancreatic hormones including insulin, glucagon, somatostatin and pancreatic polypeptide under proper conditions. Undifferentiated ES cell line was stably transfected with mouse RIP-YFP plasmid construction in serum-free medium using LipofectamineTM 2000 Reagents. We tested pancreatic specific gene expression and characterized these ESC-derived pancreatic endocrine cells. Most of these insulin-secreting cells co-expressed many of the phenotypic markers characteristic of 13 cells such as insulinl, insulin2, Isletl, MafA, insulinoma-associated antigen 1 （IA1） and so on, indicating a similar gene expression pattern to adult islet 13 cells in vivo. Characterization of this population revealed that it consisted predominantly of pancreatic endocrine cells that were able to undergo pancreatic specification under the appropriate conditions. We also demonstrated that zinc supplementation mediated up-regulation of insulin-secreting cells as an effective inducer promoted the development of ESC-derived diabetes therapy. In conclusion, this work not only established an efficient pancreatic differentiation strategy from ESCs to pancreatic endocrine lineage in vitro, but also leaded to the development of new strategies to derive transplantable islet-replacement 13 cells from embryonic stem cells for the future applications of a stem cell based therapy of diabetes.
文摘The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines （GF-CYK）： insulin-like growth factorl （IGF-Ⅰ）, insulin-like growth factorⅡ （IGF-Ⅱ）, basic fibroblast growth factor （bFGF）, leukemia inhibitory factor （LIF）, granulocyte-macrophage colony stimulating factor （GM-CSF） and transforming growth factor beta Ⅰ （TGF-β1） ＋ hyaluronan （HA） ＋ recombinant albumin （RA）. The embryos were cultured in synthetic oviduct fluid （SOF） supplemented with： treatment 1 （T1）： bovine serum albumin （BSA） ＋ insulin, transferrin and selenium （ITS） （control）; or treatment 2 （T2）： GF-CYK ＋ HA ＋ RA. The blastocyst rates were not significantly different between TI and T2, at seven days post fertilization （dpf） （28.9% ± 2.4% and 31.8% ±2.2%）, and at 8 dpf （36.5% ±2.4% and 39.1% ±1.9%）, respectively （P 〉 0.05）. The total cell number （TCN） was significantly higher with T2 than that with T1 at 7 dpf（164.9 ±5.3 and 149.7 ±4.0） and 8 dpf （182.7 ±6.4 and 165.0 ±5.5） （P 〈 0.05）. The blastocyst diameter obtained with T2 was significantly greater （P 〈 0.05） than with T1 at 7 dpf （173.3 μm ±4.9 μm and 157.2μm ±4.1 μm, respectively）, however, no significant differences were observed at 8 dpf （190.3 μm 5.2 μm and 179.7 μm ± 5.3 μm, respectively）. In conclusion, the synthetic medium （T2） shows a comparable development rate to the control medium and improves the blastocyst diameter and the TCN.
