| 1. |
- Améen, Caroline, 1975, et al.
(author)
-
Human embryonic stem cells: current technologies and emerging industrial applications.
- 2008
-
In: Critical reviews in oncology/hematology. - : Elsevier BV. - 1040-8428. ; 65:1, s. 54-80
-
Research review (peer-reviewed)abstract
- The efficiency and accuracy of the drug development process is severely restricted by the lack of functional human cell systems. However, the successful derivation of pluripotent human embryonic stem (hES) cell lines in the late 1990s is expected to revolutionize biomedical research in many areas. Due to their growth capacity and unique developmental potential to differentiate into almost any cell type of the human body, hES cells have opened novel avenues both in basic and applied research as well as for therapeutic applications. In this review we describe, from an industrial perspective, the basic science that underlies the hES cell technology and discuss the current and future prospects for hES cells in novel and improved stem cell based applications for drug discovery, toxicity testing as well as regenerative medicine.
|
|
| 2. |
- Bigdeli, Narmin, 1974, et al.
(author)
-
Adaptation of human embryonic stem cells to feeder-free and matrix-free culture conditions directly on plastic surfaces.
- 2008
-
In: Journal of biotechnology. - : Elsevier BV. - 0168-1656. ; 133:1, s. 146-53
-
Journal article (peer-reviewed)abstract
- Previous studies have shown that cultivation of undifferentiated human embryonic stem (hES) cells requires human fibroblasts (hF) or mouse embryonic fibroblast (mEF) feeders or a coating matrix such as laminin, fibronectin or Matrigeltrade mark in combination with mEF or hF conditioned medium. We here demonstrate a successful feeder-free and matrix-free culture system in which undifferentiated hES cells can be cultured directly on plastic surfaces without any supportive coating, in a hF conditioned medium. The hES cells cultured directly on plastic surfaces grow as colonies with morphology very similar to cells cultured on Matrigel(TM). Two hES cell lines SA167 and AS034.1 were adapted to matrix-free growth (MFG) and have so far been cultured up to 43 passages and cryopreserved successfully. The lines maintained a normal karyotype and expressed the expected marker profile of undifferentiated hES cells for Oct-4, SSEA-3, SSEA-4, TRA-1-60, TRA-1-81 and SSEA-1. The hES cells formed teratomas in SCID mice and differentiated in vitro into derivates of all three germ layers. Thus, the MFG-adapted hES cells appear to retain pluripotency and to remain undifferentiated. The present culture system has a clear potential to be scaleable up to a manufacturing level and become the preferred culture system for various applications such as cell therapy and toxicity testing.
|
|
| 3. |
- Bigdeli, Narmin, 1974, et al.
(author)
-
Coculture of human embryonic stem cells and human articular chondrocytes results in significantly altered phenotype and improved chondrogenic differentiation.
- 2009
-
In: Stem cells (Dayton, Ohio). - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 27:8, s. 1812-21
-
Journal article (peer-reviewed)abstract
- Human embryonic stem (hES) cells have been suggested as a cell source for the repair of cartilage lesions. Here we studied how coculture with human articular chondrocytes affects the expansion potential, morphology, expression of surface markers, and differentiation abilities of hES cells, with special regard to chondrogenic differentiation. Undifferentiated hES cells were cocultured with irradiated neonatal or adult articular chondrocytes in high-density pellet mass cultures for 14 days. Cocultured hES cells were then expanded on plastic and their differentiation potential toward the adipogenic, osteogenic, and chondrogenic lineages was compared with that of undifferentiated hES cells. The expression of different surface markers was investigated using flow cytometry and teratoma formation was studied using injection of the cells under the kidney capsule. Our results demonstrate that although hES cells have to be grown on Matrigel, the cocultured hES cells could be massively expanded on plastic with a morphology and expression of surface markers similar to mesenchymal stem cells. Coculture further resulted in a more homogenous pellet and significantly increased cartilage matrix production, both in high-density pellet mass cultures and hyaluronan-based scaffolds. Moreover, cocultured cells formed colonies in agarose suspension culture, also demonstrating differentiation toward chondroprogenitor cells, whereas no colonies were detected in the hES cell cultures. Coculture further resulted in a significantly decreased osteogenic potential. No teratoma formation was detected. Our results confirm the potential of the culture microenvironment to influence hES cell morphology, expansion potential, and differentiation abilities over several population doublings.
|
|
| 4. |
- de Peppo, Giuseppe Maria, 1981, et al.
(author)
-
Human embryonic mesodermal progenitors highly resemble human mesenchymal stem cells and display high potential for tissue engineering applications.
- 2010
-
In: Tissue engineering. Part A. - : Mary Ann Liebert Inc. - 1937-335X .- 1937-3341. ; 16:7, s. 2161-82
-
Journal article (peer-reviewed)abstract
- Adult stem cells, such as human mesenchymal stem cells (hMSCs), show limited proliferative capacity and, after long-term culture, lose their differentiation capacity and are therefore not an optimal cell source for tissue engineering. Human embryonic stem cells (hESCs) constitute an important new resource in this field, but one major drawback is the risk of tumor formation in the recipients. One alternative is to use progenitor cells derived from hESCs that are more lineage restricted but do not form teratomas. We have recently derived a cell line from hESCs denoted hESC-derived mesodermal progenitors (hES-MPs), and here, using genome-wide microarray analysis, we report that the process of hES-MPs derivation results in a significantly altered expression of hESC characteristic genes to an expression level highly similar to that of hMSCs. However, hES-MPs displayed a significantly higher proliferative capacity and longer telomeres. The hES-MPs also displayed lower expression of HLA class II proteins before and after interferon-gamma treatment, indicating that these cells may somewhat be immunoprivileged and potentially used for HLA-incompatible transplantation. The hES-MPs are thus an appealing alternative to hMSCs in tissue engineering applications and stem-cell-based therapies for mesodermal tissues.
|
|
| 5. |
- de Peppo, Giuseppe Maria, 1981, et al.
(author)
-
Osteogenic Potential of Human Mesenchymal Stem Cells and Human Embryonic Stem Cell-Derived Mesodermal Progenitors: A Tissue Engineering Perspective.
- 2010
-
In: Tissue engineering. Part A. - : Mary Ann Liebert Inc. - 1937-335X .- 1937-3341. ; 16:11, s. 3413-3426
-
Journal article (peer-reviewed)abstract
- Introduction: Human mesenchymal stem cells (hMSCs) are promising candidates for bone engineering and regeneration with a considerable number of experimental successes reported over the last years. However, hMSCs show several limitations for tissue engineering applications, which can be overcome by using human embryonic stem cell-derived mesodermal progenitors (hES-MPs). The aim of this study was to investigate and compare the osteogenic differentiation potential of hMSCs and hES-MPs. Materials and Methods: The osteogenic differentiation and mineralization behavior of both cell types were evaluated at passage 5, 10, 15, and 20. Expression of COL1A1, RUNX2, OPN, and OC was evaluated by reverse transcription (RT)-polymerase chain reaction, whereas mineralization was examined by photospectrometry, von Kossa staining, and time-of-flight secondary ion mass spectrometry. The immunoprofile of both cell types was investigated by flow cytometry. Results: We demonstrated that, under proper stimulation, hES-MPs undergo osteogenic differentiation and exhibit significantly increased mineralization ability compared to hMSCs after protracted expansion. hES-MPs were also found to express lower amount of human leukocyte antigens class II proteins. Conclusions: The high osteogenic ability of hES-MPs, together with low expression of human leukocyte antigens class II, makes these cells an attractive alternative for bulk production of cells for bone engineering applications.
|
|
| 6. |
|
|
| 7. |
- Ellerström, Catharina, et al.
(author)
-
Facilitated expansion of human embryonic stem cells by single-cell enzymatic dissociation
- 2007
-
In: Stem Cells. - : Oxford University Press (OUP). - 1549-4918 .- 1066-5099. ; 25:7, s. 1690-1696
-
Journal article (peer-reviewed)abstract
- Traditionally, human embryonic stem cells (hESCs) are propagated by mechanical dissection or enzymatic dissociation into clusters of cells. To facilitate up-scaling and the use of hESC in various experimental manipulations, such as fluorescence-activated cell sorting, electroporation, and clonal selection, it is important to develop new, stable culture systems based on single-cell enzymatic propagation. Here, we show that hESCs, which were derived and passaged by mechanical dissection, can be rapidly adjusted to propagation by enzymatic dissociation to single cells. As an indication of the stability of this culture system, we demonstrate that hESCs can be maintained in an undifferentiated, pluripotent, and genetically normal state for up to 40 enzymatic passages. We also demonstrate that a recombinant trypsin preparation increases clonal survival compared with porcine trypsin. Finally, we show that human foreskin fibroblast feeders are superior to the commonly used mouse embryonic fibroblast feeders in terms of their ability to prevent spontaneous differentiation after single-cell passaging. Importantly, the culture system is widely applicable and should therefore be of general use to facilitate reliable large-scale cultivation of hESCs, as well as their use in various experimental manipulations.
|
|
| 8. |
- Englund, Mikael C. O., 1971, et al.
(author)
-
The establishment of 20 different human embryonic stem cell lines and subclones; a report on derivation, culture, characterisation and banking.
- 2010
-
In: In vitro cellular & developmental biology. Animal. - : Springer Science and Business Media LLC. - 1543-706X .- 1071-2690. ; 46:3-4, s. 217-30
-
Journal article (peer-reviewed)abstract
- This report summarises our efforts in deriving, characterising and banking of 20 different human embryonic stem cell lines. We have derived a large number of human embryonic stem cell lines between 2001 and 2005. One of these cell lines was established under totally xeno-free culture conditions. In addition, several subclones have been established, including a karyoptypical normal clone from a trisomic mother line. A master cell banking system has been utilised in concert with an extensive characterisation programme, ensuring a supply of high quality pluripotent stem cells for further research and development. In this report we also present the first data on a proprietary novel antibody, hES-Cellect, that exhibits high specificity for undifferentiated hES cells. In addition to the traditional manual dissection approach of propagating hES cells, we here also report on the successful approaches of feeder-free cultures as well as single cell cultures based on enzymatic digestion. All culture systems used as reported here have maintained the hES cells in a karyotypical normal and pluripotent state. These systems also have the advantage of being the principal springboards for further scale up of cultures for industrial or clinical applications that would require vastly more cells that can be produced by mechanical means.
|
|
| 9. |
- Håkansson, Joakim, et al.
(author)
-
De- and recellularized urethral reconstruction with autologous buccal mucosal cells implanted in an ovine animal model
- 2023
-
In: Biomedizinische Technik (Berlin. Zeitschrift). - : De Gruyter Open Ltd. - 1862-278X .- 0013-5585. ; 68:5, s. 493-
-
Journal article (peer-reviewed)abstract
- Patients with urethral stricture due to any type of trauma, hypospadias or gender dysphoria suffer immensely from impaired capacity to urinate and are in need of a new functional urethra. Tissue engineering with decellularization of a donated organ recellularized with cells from the recipient patient has emerged as a promising alternative of advanced therapy medicinal products. The aim of this pilot study was to develop an ovine model of urethral transplantation and to produce an individualized urethra graft to show proof of function in vivo. Donated urethras from ram abattoir waste were decellularized and further recellularized with autologous buccal mucosa epithelial cells excised from the recipient ram and expanded in vitro. The individualized urethral grafts were implanted by reconstructive surgery in rams replacing 2.5 ± 0.5 cm of the native penile urethra. After surgery optimization, three ram had the tissue engineered urethra implanted for one month and two out of three showed a partially regenerated epithelium. Further adjustments of the model are needed to achieve a satisfactory proof-of-concept; however, we interpret these findings as a proof of principle and a possible path to develop a functional tissue engineered urethral graft with de- and recellularization and regeneration in vivo after transplantation.
|
|
| 10. |
- Jergil, Måns, et al.
(author)
-
Exploring Transcriptional Response toValproic Acid and Valproic Acid Analogs in Human Embryonic Stem Cells
-
Other publication (pop. science, debate, etc.)abstract
- Developmental toxicity is a major concern for manufacturers of new pharmaceuticals,and current testing requires many laboratory animals. Human embryonic stem (hES)cells, potentially being close in function to cells in the developing embryo, mayprovide a technology for classification of candidate drugs in the early phase of toxicityevaluation. Altered gene expression in such system may be predictive of teratogenicproperties of a substance if important gene regulatory pathways are affected, and mayhence be used as appropriate endpoint. In the present study we used the pluripotenthES cell line SA002 (Cellartis AB), and microarrays to profile the response tovalproic acid (VPA), a known human teratogen causing increased risk of e.g. spinabifida and cognitive disorders in exposed embryos We also investigated three closelyrelated VPA analogs with differing in vivo teratogenicity in mice as well as histonedeacetylase (HDAC) inhibition, a proposed teratogenic mechanism of VPA. hEScells in an undifferentiated state were exposed for 24 h to either 1 mM VPA, 0.25mM or 0.5 mM (S)-2-pentyl-4-pentynoic acid a more potent teratogen and HDACinhibitor than VPA, 1 mM 3-propyl-heptanoic acid, a potent teratogen but not anHDAC inhibitor, 1 mM 2-ethyl-4-methyl-pentanoic acid, a non-teratogen and non-HDAC inhibitor, or 0.1% DMSO. Gene expression was subsequently profiled usingCodelink Human Whole Genome BioArrays. We found the HDAC inhibitors tostrongly deregulate largely the same genes. Further, a concordance of altered geneontology groups, predominantly neurogenic processes, was evident between all theteratogenic substances. Also, comparison with mouse ES cells showed an overlap ofderegulated genes as well as species specific gene to be deregulated.
|
|
