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标题: Human-Serum Matrix Supports Undifferentiated Growth of Human Embryonic Stem Cell [打印本页]

作者: 江边孤钓    时间: 2009-3-5 10:49     标题: Human-Serum Matrix Supports Undifferentiated Growth of Human Embryonic Stem Cell

a Centre for Stem Cell Biology and Developmental Genetics, Institute of Human Genetics, University of Newcastle, Newcastle upon Tyne, United Kingdom;3 f  |7 S' M$ h8 R4 t
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b School of Biological and Biomedical Sciences, University of Durham, Durham, United Kingdom;& L# E8 o0 ], |( l$ V; N/ v5 q
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c Institute of Human Genetics, University of Newcastle, Newcastle upon Tyne, United Kingdom
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Key Words. Human embryonic stem cells ? Pluripotency ? Differentiation ? Feeder-free, b& K" ]1 o# B% M* V1 z
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Correspondence: M. Stojkovic, Ph.D., Centre for Stem Cell Biology and Developmental Genetics, Institute of Human Genetics, University of Newcastle, Newcastle upon Tyne, U.K. Telephone: 44-191-241-8638; Fax: 44-191-219-4747; e-mail: miodrag.stojkovic@ncl.ac.uk. _! o8 n; l" C3 F
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ABSTRACT0 g4 e4 N" U& X! Y! ^( Z

3 n) H5 |" s. E5 }Human embryonic stem cells (hESCs) have been derived from the inner cell mass (ICM) of day-5 through -8 blastocysts . To date, derivation and propagation of undifferentiated hESCs requires plating of both ICM and hESC colonies on mouse embryonic fibroblast (MEF) cells or human feeder (HFF) cells , and this limits the large-scale culture and genetic manipulation of hESCs . To overcome these obstacles, feeder-free systems have been introduced in which hESCs can be grown on different matrices with addition of MEF-conditioned medium or hESC medium supplemented with serum replacement, different growth factors, or in the presence of 6-bromoindirubin-3'-oxime, a specific pharmacological inhibitor of glycogen synthase kinase-3 ./ w1 o! C- K' S8 X

6 A8 S, V$ R8 J0 ^! d  M% _One of the most frequently used matrices for feeder-free growth of undifferentiated hESCs is Matrigel, which supports attachment and growth of undifferentiated hESCs in the presence of MEF-conditioned medium . Matrigel is ananimal basement membrane preparation extracted from Engelbreth-Holm-Swarm mouse sarcoma, a tumor rich in extracellular matrix (ECM) proteins: laminin, collagen IV, heparan sulfate proteoglycans, entactin, and nidogen 1. Unfortunately, application of Matrigel or MEF-conditioned medium is not ideal for potential medical application of hESCs because xenogeneic pathogens can be transmitted through culture conditions .. x: N; d$ M9 Z7 g  [4 N9 t; h

  Q' N3 W+ N6 t! Q+ vWe previously demonstrated  that hESCs could be successfully grown on Matrigel with addition of medium conditioned by the fibroblasts derived from differentiated hESCs (hES-dF). In this manuscript, we evaluated whether human serum (HS) could be successfully used as a matrix to help the attachment and growth of hESCs with the aim to create feeder-free and more patient-friendly conditions for the long-term growth of undifferentiated hESCs. We demonstrate here that HS and medium conditioned by hES-dF reduce exposure of hESCs to animal ingredients and provide a safer direction toward completely animal-free conditions for application, handling, and understanding of hESC biology. At the same time, hESCs grown under these conditions maintain all hESC features after prolonged culture, including the developmental potential to differentiate into representative tissues of all three embryonic germ layers, unlimited and undifferentiated proliferative ability, and maintenance of normal karyotype.( L. j2 d2 L; T( ~% c" F* @
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MATERIALS AND METHODS
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Surfaces of culture plates coated with Matrigel or HS were investigated using scanning electron microscopy. This analysis revealed that coating with Matrigel or HS provides a substratum with similar shape (Figs. 1A, 1B), which assists cell adhesion and supports undifferentiated growth of both hESC lines, hES-NCL1 and H1 (Figs. 1C, 1D). When transferred on uncoated plates, hESC colonies do not attach; however, they do form embryoid bodies (not shown) or attach and spontaneously differentiate. On the contrary, both lines cultured on HS and in the presence of hES-dF medium kept their pluripotency for over 27 passages. We found that undifferentiated hESCs grown on HS show typical morphology, that is, small cells with prominent nucleoli (Figs. 2A, 2B) expressing typical cell-surface and intracellular hESC markers: TRA-1-60 (Fig. 2C), TRA-1-81 (Fig. 2D), SSEA-4 (Fig. 2E), AP (Fig. 2F), and OCT-4 (Fig. 2G). When hESCs of both cell lines were grown on HS and in the absence of hES-dF medium, spontaneous differentiation was observed 48 hours after passaging (Fig. 2I). RT-PCR analysis of undifferentiated hESCs showed positive expression of OCT-4, REX-1, NANOG, and TERT (Fig. 2J). Comparative flow cytometry analysis revealed that hES-NCL1 cells grown on Matrigel or HS for 21 passages expressed 79.1% and 81.5% of TRA-1-81 antigen, respectively (data not shown).6 q7 R: |  s2 Y3 Y1 a
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Figure 1. Environmental SEM of dishes coated with (A) Matrigel or (B) HS and SEM of hES-NCL1 cells grown on (C) HS or on (D) Matrigel. Note the crystal-like structure in both coated plates and similar morphology, that is, flat surface of the hESCs grown on HS (C; 4-day-old colony, passage 15) or Matrigel (D; 6-day-old colony, passage 14) in the presence of hES-dF–conditioned medium. Spontaneously differentiated hESCs and surface of noncoated plastic dish are presented in (E) and (F), respectively. (E): Note the diversity in the shape of different spontaneously differentiated hESCs. Bars: 20 μm (A, B, E); 50 μm (F); 200 μm (C, D). Abbreviations: hESC, human embryonic stem cell; hES-dF, differentiated hESC; HS, human serum; SEM, scanning electron microscopy.8 ?, k; U4 S  b" W5 K6 @3 j' x% a2 w
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Figure 2. Morphology and characterization of (A–E; passage 13) hES-NCL1 and (D–H; passage 15) H1 cells grown on HS in the presence of hES-dF–conditioned medium. (B): Higher magnification of the hESC colony. Note typical morphology of hESCs, that is, high nucleus to cytoplasm ratio, presence of nucleoli. hESCs grown on HS and hES-dF–conditioned medium stained with antibody recognizing the (C) TRA-1-60, (D) TRA-1-81, (E) SSEA-4, (F) alkaline phosphates, and (G) OCT-4 epitopes. (H): Negative OCT-4 control. (I): H1 cells grown on HS in the absence of hES-dF but in the presence of ES medium spontaneously differentiated already after 2 days. (J): RT-PCR analysis of undifferentiated hES-NCL1 (passage 16) cells grown on HS. RT-PCR was proceeded with ( ) or without (–) reverse transcription. PCR products obtained using primers specific for OCT-4, REX1, TERT, NANOG, and GAPDH. (C, D): Red color represents cell nuclei stained with propidium iodide. Bars: 25 μm (B); 50 μm (C); 100 μm (A, D, E); 200 μm (F, G, H, I). Abbreviations: hESC, human embryonic stem cell; hES-dF, differentiated hESC; HS, human serum; RT-PCR, reverse transcription–polymerase chain reaction.( S/ t! b! y3 N/ @

- G0 n% f6 K1 \0 ]Karyotyping of the hESCs showed that both lines hES-NCL1 and H1 grown on HS in the presence of hES-dF–conditioned medium have a normal female or male karyotype (Figs. 3A, 3B), keeping their genomic stability even after 21 passages.! {2 [" y- }2 G, Q. k4 U

0 H  s9 Y/ n) D: r3 nFigure 3. Karyotyped (A) hES-NCL1 and (B) H1 (both passage 17) cells grown on HS in the presence of hES-dF–conditioned medium keep their stability and show a normal female and male karyotype, respectively. Abbreviations: hES-dF, differentiated hESC; HS, human serum.
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When hES-NCL1 or H1 cells grown on HS in the presence of hES-dF–conditioned medium were not replated after 4–6 days (see Material and Methods), spontaneous differentiation into neuronal precursor, fat cells, cardiomyocytes, and endoderm-like cells was observed (Figs. 4A–4D). The presence of the cells of all three germ lineages was confirmed by RT-PCR, in which expression of cytokeratin 3 (CK3), cytokeratin 19 (CK19) PAX6, NESTIN, GATA4, and Indian hedgehog genes was observed (Fig. 4E). This demonstrates that both hESC lines cultured on HS have the potential to spontaneously differentiate into cells of all three germ layers under in vitro conditions. PCR analysis of undifferentiated hESCs using the same markers as for differentiated hESCs showed only expression of CK19 (Fig. 4F)." D" u$ ^' S  o" B
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Figure 4. Spontaneous differentiation of hES-NCL1 and H1 cells grown on HS in the presence of hES-dF–conditioned medium. hES-NCL1 (passage 19) spontaneously differentiates into (A) neuronal, (B) fat, (C) contracting cardiac muscle, and (D) endoderm-like cells, demonstrating their differentiation ability under our in vitro growth conditions. Green color represents cells stained with (A) tubulin ? III, (C) -actin sarcomeric, and (D) -fetoprotein antibodies. (B): Red color represents fat cells stained with oil red O staining.(A, C, D):Blue color represents nuclei stained with Hoechst. (E): RT-PCR analysis of differentiated H1 (passage 16) cells grown on HS demonstrating differentiation ability of hESCs into all three germ layers. PCR products obtained using primers specific for cytokeratin 3 (CK3), cytokeratin 19(CK19), Pax6, Nestin, Gata4, Indian hed gehog (IHH), and GAPDH genes. (F): Undifferentiated H1 cell expressed only CK19. Scale bars: 100 μm (A); 50 μm (B, D); 25 μm (C). Abbreviations: hESC, human embryonic stem cell; hES-dF, differentiated hESC; HS, human serum; RT-PCR, reverse transcription–polymerase chain reaction.
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Under in vivo conditions, hES-NCL1 grown on HS and in the presence of hES-dF–conditioned medium consistently developed into teratomas when grafted into SCID mice. The teratomas were always restricted to the site of transplantation. Gross analysis of excised tumor tissues showed solid teratomas and lesions containing fluid-filled cystic masses accompanied with solid tissues. Histological examination of teratomas revealed advanced differentiation of structures representative of all three embryonic germ layers, including cartilage, muscle, primitive neuroectoderm, neural ganglia, kidney, secretory epithelia, and connective tissues (Figs. 5A–5F). Moreover, such tissues formed complex arrangements, recapitulating the development of complex structures that no doubt require coordinated interactions between different cell types derived from different germ layers.% E+ N. w+ |& P
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Figure 5. Histological analysis of teratomas formed from grafted colonies of human feeder–independent hES-NCL1 cells in SCID mice. (A): General structure of teratoma showing a range of different tissue types, including cartilage (cart), muscle (mus) and epithelia (ep). (B): Higher magnification example of cartilage (cart) and an adjacent neural element (ne). (C): Wall of intestinal tract showing epithelium (ep), mucosa (m), smooth muscle layer (mus), submucosal glands (sg), and neural elements (ne). (D): Higher magnification image of intestinal mucosa (m). The epithelium is typical of that found in the large intestine and consists of a single layer of columnar cells that primarily secrete mucous. (E): Longitudinal section through smooth muscle (mus). (F): Kidney tissue including glomerulus (glom) with surrounding Bowman’s space and adjacent tubules (tub). Note the vascular pole of the glomerulus and the presence of a blood vessel (bv). Histological staining: (A–C, E) Weigert’s and (D, F) hematoxylin and eosin. Scale bars: 500 μm (A); 100 μm (B, D–F); 200 μm (C). Abbreviation: SCID, severe combined immunodeficient.7 d5 S) K1 M; t6 b

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3 S$ R5 Z, n% K2 wThe authors would like to thank Vivian Thompson, Tracey Scott-Davey (Biomedical EM Unit, Newcastle University, Newcastle upon Tyne), and Grant Staines (SAgE Faculty Services, Newcastle University) for SEM and ESEM analysis. This work was supported by Newcastle University Hospitals Special Trustees, One NorthEast Regional Development Agency (Newcastle), Newcastle Health Charity, the Department of Health, and Medical Research Council, London, grant No. G0301182.4 D) I6 K) r' [& L

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作者: 陈晴    时间: 2017-9-9 01:34

间充质干细胞
作者: 心仪    时间: 2017-9-10 22:54

心脏干细胞
作者: 命运的宠儿    时间: 2017-9-21 00:00

回复一下  
作者: 安安    时间: 2017-10-26 16:39

站个位在说  
作者: dypnr    时间: 2017-11-5 21:52

天啊. 很好的资源
作者: haha3245    时间: 2017-11-25 11:10

留个脚印```````  
作者: Diary    时间: 2017-12-9 16:18

小心大家盯上你哦  
作者: 未必温暖    时间: 2017-12-14 04:05

我来看看!谢谢  
作者: 快乐小郎    时间: 2017-12-14 04:44

又看了一次  
作者: dd赤焰    时间: 2018-1-11 12:08

真是有你的!  
作者: 糊涂小蜗牛    时间: 2018-2-2 16:01

ding   支持  
作者: 分子工程师    时间: 2018-2-3 06:39

发贴看看自己积分  
作者: 追风    时间: 2018-2-10 02:32

我又回复了  
作者: dypnr    时间: 2018-2-16 00:34

继续查找干细胞研究资料
作者: netlover    时间: 2018-2-17 14:27

哦...............  
作者: 泡泡鱼    时间: 2018-3-3 15:43

只有一条路不能选择——那就是放弃的路;只有一条路不能拒绝——那就是成长的路。  
作者: alwaysniu    时间: 2018-3-14 12:35

我十目一行也还是看不懂啊  
作者: lalala    时间: 2018-4-11 18:06

似曾相识的感觉  
作者: bluesuns    时间: 2018-4-12 15:09

又看了一次  
作者: 我心飞翔    时间: 2018-4-13 10:43

顶你一下,好贴要顶!  
作者: 水木清华    时间: 2018-4-15 16:53

帮你项项吧  
作者: biobio    时间: 2018-4-30 23:27

也许似乎大概是,然而未必不见得。  
作者: 风云动    时间: 2018-6-4 17:10

宁愿选择放弃,不要放弃选择。  
作者: lalala    时间: 2018-7-7 02:08

你加油吧  
作者: 化药所    时间: 2018-8-8 18:25

先看看怎么样!  
作者: 糊涂小蜗牛    时间: 2018-9-20 23:25

谁都不容易啊 ~~  
作者: 大小年    时间: 2018-9-22 02:34

非常感谢楼主,楼主万岁万岁万万岁!  
作者: 剑啸寒    时间: 2018-10-2 05:36

这年头,分不好赚啊  
作者: 咖啡功夫猫    时间: 2018-10-12 02:56

这个贴不错!!!!!  
作者: laoli1999    时间: 2018-12-7 20:43

顶你一下,好贴要顶!  
作者: 考拉    时间: 2018-12-16 09:18

做一个,做好了,请看  
作者: 安生    时间: 2018-12-20 15:13

只有一条路不能选择——那就是放弃的路;只有一条路不能拒绝——那就是成长的路。  
作者: feixue66    时间: 2018-12-27 02:18

强人,佩服死了。呵呵,不错啊  
作者: 龙水生    时间: 2019-1-8 11:01

人气还要再提高  
作者: 龙水生    时间: 2019-1-17 04:16

淋巴细胞
作者: 王者之道    时间: 2019-1-23 06:38

好贴坏贴,一眼就看出去  
作者: Greatjob    时间: 2019-1-29 08:43

真好。。。。。。。。。  
作者: biodj    时间: 2019-2-8 14:18

有空一起交流一下  
作者: 与你同行    时间: 2019-2-16 09:16

(*^__^*) 嘻嘻……  
作者: 心仪    时间: 2019-2-25 03:32

挺好啊  
作者: s06806    时间: 2019-3-2 01:38

加油啊!!!!顶哦!!!!!  
作者: foxok    时间: 2019-4-17 15:27

不看白不看,看也不白看  




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