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
Human induced pluripotent stem （iPS） cells are similar to embryonic stem （ES） cells, and can proliferate intensively and differentiate into a variety of cell types. However, the hepatic differentiation of human iP...Human induced pluripotent stem （iPS） cells are similar to embryonic stem （ES） cells, and can proliferate intensively and differentiate into a variety of cell types. However, the hepatic differentiation of human iPS cells has not yet been reported. In this report, human iPS cells were induced to differentiate into hepatic cells by a stepwise protocol. The expression of liver cell markers and liver-related functions of the human iPS cell-derived cells were monitored and compared with that of differentiated human ES cells and primary human hepatocytes. Approximately 60% of the differentiated human iPS cells at day 7 expressed hepatic markers alpha fetoprotein and Alb. The differentiated cells at day 21 exhibited liver cell functions including albumin Asecretion, glycogen synthesis, urea production and inducible cytochrome P450 activity. The expression of hepatic markers and fiver-related functions of the iPS cellderived hepatic ceils were comparable to that of the human ES cell-derived hepatic cells. These results show that human iPS cells, which are similar to human ES cells, can be efficiently induced to differentiate into hepatocyte-like cells.展开更多
AIM:To evaluate diagnostic value ofα-fetoprotein (AFP)-L3 and prothrombin induced by vitamin K absence-Ⅱ(PIVKA-Ⅱ)in hepatocellular carcinoma(HCC). METHODS:One hundred and sixty-eight patients during routine HCC sur...AIM:To evaluate diagnostic value ofα-fetoprotein (AFP)-L3 and prothrombin induced by vitamin K absence-Ⅱ(PIVKA-Ⅱ)in hepatocellular carcinoma(HCC). METHODS:One hundred and sixty-eight patients during routine HCC surveillance were included in this study.Of the 168 patients,90(53.6%)had HCC including newly developed HCC(n=82)or recurrent HCC after treatment(n=8).Sera were obtained during their first evaluation for HCC development and at the time of HCC diagnosis before commencing HCC treatment.HCC was diagnosed by histological examination,appropriate imaging characteristics-computed tomography or magnetic resonance imaging.Control sera were collected from 78 patients with benign liver disease(BLD),which were obtained during routine surveillance with a suspicion of HCC.AFP,AFP-L3 and PIVKA-Ⅱwere measured in the same serum by microchip capillary electrophoresis and liquid-phase binding assay on a micro-total analysis system Wako i30 auto analyzer.The performance characteristics of three tests and combined tests for the diagnosis of HCC were obtained using receiver operating characteristic curves in all populations and subgroups with AFP<20 ng/mL. RESULTS:Of 90 HCC patients,38(42.2%)patients had AFP<20 ng/mL,20(22.2%)patients had AFP 20-200 ng/mL and 32(35.6%)patients had AFP>200 ng/mL.Of the 78 BLD patients,74(94.9%)patients had AFP<20 ng/mL.After adjustment for age and HBV infection status,AFP-L3 levels were higher in HCC than in BLD among patients with low AFP levels(<20 ng/mL)(P<0.001).In a total of 168 patients,areas under the curve(AUC)for HCC were 0.879,0.887,0.801 and 0.939 for AFP,AFP-L3,PIVKA-Ⅱand the combined markers,respectively.The combined AUC for three markers showed higher value than the AUCs of individual marker(P<0.05).AFP-L3 had higher AUC value than PIVKA-Ⅱfor HCC detection in entire patients(P =0.043).With combination of AFP-L3(cut-off>5%) and PIVKA-Ⅱ(cut-off>40 AU/L),the sensitivity were 94.4%and specificity were 75.6%in all patients.In 112 patients with low AFP levels(<20 ng/mL),AUCs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We thank Dr Zicai Liang and Huang Huang （Institute of Molecular Medicine, Peking University） for their kind help with BioTek Multi-Detection Microplate Reader and Yizhe Zhang for technical support on real-time PCR. We also thank Chengyan Wang, Pengbo Zhang, Pingping Hou, Haisong Liu, Chun Liu and other colleagues in our laboratory for technical assistance and advice in carrying out these experiments. This study was supported by a Bill ＆ Melinda Gates Foundation Grant （37871）, a Ministry of Education grant （705001）, the National Basic Research Program of China （973 program, 2009CB522502, 2009CB941200 and 2007CB947901）, National Natural Science Foundation of China for Creative Research Groups （30421004）, the Chinese Science and Technology Key Project （2008zx10002-014, 2008zx10002- 011 and 2009ZX 10004-403） and a 111 Project to Deng H.
文摘Human induced pluripotent stem （iPS） cells are similar to embryonic stem （ES） cells, and can proliferate intensively and differentiate into a variety of cell types. However, the hepatic differentiation of human iPS cells has not yet been reported. In this report, human iPS cells were induced to differentiate into hepatic cells by a stepwise protocol. The expression of liver cell markers and liver-related functions of the human iPS cell-derived cells were monitored and compared with that of differentiated human ES cells and primary human hepatocytes. Approximately 60% of the differentiated human iPS cells at day 7 expressed hepatic markers alpha fetoprotein and Alb. The differentiated cells at day 21 exhibited liver cell functions including albumin Asecretion, glycogen synthesis, urea production and inducible cytochrome P450 activity. The expression of hepatic markers and fiver-related functions of the iPS cellderived hepatic ceils were comparable to that of the human ES cell-derived hepatic cells. These results show that human iPS cells, which are similar to human ES cells, can be efficiently induced to differentiate into hepatocyte-like cells.
基金Supported by The Industrial Core Technology Development Program funded by the Ministry of Knowledge Economy,No.10033183
文摘AIM:To evaluate diagnostic value ofα-fetoprotein (AFP)-L3 and prothrombin induced by vitamin K absence-Ⅱ(PIVKA-Ⅱ)in hepatocellular carcinoma(HCC). METHODS:One hundred and sixty-eight patients during routine HCC surveillance were included in this study.Of the 168 patients,90(53.6%)had HCC including newly developed HCC(n=82)or recurrent HCC after treatment(n=8).Sera were obtained during their first evaluation for HCC development and at the time of HCC diagnosis before commencing HCC treatment.HCC was diagnosed by histological examination,appropriate imaging characteristics-computed tomography or magnetic resonance imaging.Control sera were collected from 78 patients with benign liver disease(BLD),which were obtained during routine surveillance with a suspicion of HCC.AFP,AFP-L3 and PIVKA-Ⅱwere measured in the same serum by microchip capillary electrophoresis and liquid-phase binding assay on a micro-total analysis system Wako i30 auto analyzer.The performance characteristics of three tests and combined tests for the diagnosis of HCC were obtained using receiver operating characteristic curves in all populations and subgroups with AFP<20 ng/mL. RESULTS:Of 90 HCC patients,38(42.2%)patients had AFP<20 ng/mL,20(22.2%)patients had AFP 20-200 ng/mL and 32(35.6%)patients had AFP>200 ng/mL.Of the 78 BLD patients,74(94.9%)patients had AFP<20 ng/mL.After adjustment for age and HBV infection status,AFP-L3 levels were higher in HCC than in BLD among patients with low AFP levels(<20 ng/mL)(P<0.001).In a total of 168 patients,areas under the curve(AUC)for HCC were 0.879,0.887,0.801 and 0.939 for AFP,AFP-L3,PIVKA-Ⅱand the combined markers,respectively.The combined AUC for three markers showed higher value than the AUCs of individual marker(P<0.05).AFP-L3 had higher AUC value than PIVKA-Ⅱfor HCC detection in entire patients(P =0.043).With combination of AFP-L3(cut-off>5%) and PIVKA-Ⅱ(cut-off>40 AU/L),the sensitivity were 94.4%and specificity were 75.6%in all patients.In 112 patients with low AFP levels(<20 ng/mL),AUCs
