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Fibronectin-conjugated thermoresponsive nanobridges generate three dimensional human pluripotent stem cell cultures for differentiation towards the neural lineages. Stem Cell Res 2019; 38:101441. [PMID: 31082678 DOI: 10.1016/j.scr.2019.101441] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/31/2019] [Accepted: 04/15/2019] [Indexed: 12/12/2022] Open
Abstract
Production of 3-dimensional neural progenitor cultures from human pluripotent stem cells offers the potential to generate large numbers of cells. We utilised our nanobridge system to generate 3D hPSC aggregates for differentiation towards the neural lineage, and investigate the ability to passage aggregates while maintaining cells at a stem/progenitor stage. Over 38 days, aggregate cultures exhibited upregulation and maintenance of neural-associated markers and demonstrated up to 10 fold increase in cell number. Aggregates undergoing neural induction in the presence or absence of nanobridges demonstrated no differences in marker expression, proliferation or viability. However, aggregates formed without nanobridges were statistically significantly fewer and smaller by passage 3. Organoids, cultured from aggregates, and treated with retinoic acid or rock inhibitor demonstrated terminal differentiation as assessed by immunohistochemistry. These data demonstrate that nanobridge 3D hPSC can differentiate to neural stem/progenitor cells, and be maintained at this stage through serial passaging and expansion.
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Media composition modulates human embryonic stem cell morphology and may influence preferential lineage differentiation potential. PLoS One 2019; 14:e0213678. [PMID: 30889226 PMCID: PMC6424453 DOI: 10.1371/journal.pone.0213678] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 02/26/2019] [Indexed: 12/22/2022] Open
Abstract
Undifferentiated human embryonic stem cells have a distinct morphology (hESC). Changes in cell morphology during culture can be indicative of differentiation. hESC, maintained in diverse medias, demonstrated alterations in morphological parameters and subsequent alterations in underlying transcript expression and lineage differentiation. Analysis of morphological parameters showed distinct and significant differences between the undefined, less defined and Xeno-free medias while still maintaining pluripotency markers. This suggested that the less defined media may be creating dynamic instability in the cytoskeleton, with the cytoskeleton becoming more stabilised in the Xeno-free media as demonstrated by smaller and rounder cells. Examination of early lineage markers during undirected differentiation using d5 embryoid bodies demonstrated increased mesodermal lineage preference as compared to endodermal or ectoderm in cells originally cultured in Xeno-free media. Undefined media showed preference for mesoderm and ectoderm lineages, while less defined media (BSA present) demonstrated no preference. These data reveal that culture media may produce fundamental changes in cell morphology which are reflected in early lineage differentiation choice.
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Canine CD117-Specific Antibodies with Diverse Binding Properties Isolated from a Phage Display Library Using Cell-Based Biopanning. Antibodies (Basel) 2019; 8:E15. [PMID: 31544821 PMCID: PMC6640692 DOI: 10.3390/antib8010015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 12/28/2018] [Accepted: 01/29/2019] [Indexed: 12/11/2022] Open
Abstract
CD117 (c-Kit) is a tyrosine kinase receptor that is overexpressed in multiple dog tumors. There is 100% homology between the juxtamembrane domain of human and canine CD117, and many cancer-causing mutations occur in this region in both species. Thus, CD117 is an important target for cancer treatment in dogs and for comparative oncology studies. Currently, there is no monoclonal antibody (mAb) specifically designed to target the exposed region of canine CD117, although there exist some with species cross-reactivity. We panned a naïve phage display library to isolate antibodies against recombinant CD117 on whole cells. Several mAbs were isolated and were shown to bind recombinant canine CD117 at low- to sub-nanomolar affinity. Additionally, binding to native canine CD117 was confirmed by immunohistochemistry and by flow cytometry. Competitive binding assays also identified mAbs that competed with the CD117 receptor-specific ligand, the stem cell factor (SCF). These results show the ability of our cell-based biopanning strategy to isolate a panel of antibodies that have varied characteristics when used in different binding assays. These in vitro/ex vivo assessments suggest that some of the isolated mAbs might be promising candidates for targeting overexpressed CD117 in canine cancers for different useful applications.
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TAFA2 Induces Skeletal (Stromal) Stem Cell Migration Through Activation of Rac1-p38 Signaling. Stem Cells 2018; 37:407-416. [PMID: 30485583 PMCID: PMC7379704 DOI: 10.1002/stem.2955] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 10/17/2018] [Accepted: 10/25/2018] [Indexed: 12/14/2022]
Abstract
Understanding the mechanisms regulating recruitment of human skeletal (stromal or mesenchymal) stem cells (hMSC) to sites of tissue injury is a prerequisite for their successful use in cell replacement therapy. Chemokine‐like protein TAFA2 is a recently discovered neurokine involved in neuronal cell migration and neurite outgrowth. Here, we demonstrate a possible role for TAFA2 in regulating recruitment of hMSC to bone fracture sites. TAFA2 increased the in vitro trans‐well migration and motility of hMSC in a dose‐dependent fashion and induced significant morphological changes including formation of lamellipodia as revealed by high‐content‐image analysis at single‐cell level. Mechanistic studies revealed that TAFA2 enhanced hMSC migration through activation of the Rac1‐p38 pathway. In addition, TAFA2 enhanced hMSC proliferation, whereas differentiation of hMSC toward osteoblast and adipocyte lineages was not altered. in vivo studies demonstrated transient upregulation of TAFA2 gene expression during the inflammatory phase of fracture healing in a closed femoral fracture model in mice, and a similar pattern was observed in serum levels of TAFA2 in patients after hip fracture. Finally, interleukin‐1β was found as an upstream regulator of TAFA2 expression. Our findings demonstrate that TAFA2 enhances hMSC migration and recruitment and thus is relevant for regenerative medicine applications. Stem Cells2019;37:407–416
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Molecular Phenotyping of Telomerized Human Bone Marrow Skeletal Stem Cells Reveals a Genetic Program of Enhanced Proliferation and Maintenance of Differentiation Responses. JBMR Plus 2018; 2:257-267. [PMID: 30283907 PMCID: PMC6139702 DOI: 10.1002/jbm4.10050] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 03/15/2018] [Accepted: 03/24/2018] [Indexed: 12/15/2022] Open
Abstract
Long-term in vitro expansion of bone marrow stromal (skeletal) stem cells (also known as human mesenchymal stem cells [hMSC]) is associated with replicative senescence and impaired functions. We have previously reported that telomerization of hMSC through hTERT overexpression led to bypassing a replicative senescence phenotype and improved in vitro and in vivo functions. However, the molecular consequence of telomerization is poorly characterized. Thus, we compared the molecular phenotype of a well-studied telomerized hMSC (hMSC-TERT) cell line with primary hMSC. At a cellular level, both cell populations exhibited strong concordance for the known hMSC CD markers, similar responses to osteoblast (OB) differentiation induction, and formed heterotopic bone in vivo. Overall gene expression was highly correlated between both cell types with an average Pearson's correlation coefficient (R2) between the gene expression of all primary hMSC and all hMSC-TERT samples of 0.95 (range 0.93-0.96). Quantitative analysis of gene expression of CD markers, OB cell markers, and transcription factors (TF) showed a high degree of similarity between the two cell populations (72%, 77%, and 81%, respectively). The hMSC-TERT population was enriched mainly for genes associated with cell cycle and cell cycle signaling when compared with primary hMSC. Other enrichment was observed for genes involved in cell adhesion and skeletal system development and immune response pathways. Interestingly, hMSC-TERT shared a telomerization signature with upregulation of cancer/testis antigens, MAGE, and PAGE genes. Our data demonstrate that the enhanced biological characteristics of hMSC after telomerization are mainly due to enhanced expression of cell proliferation genes, whereas gene expression responses to differentiation are maintained. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Methods for Expansion of Three-Dimensional Cultures of Human Embryonic Stem Cells Using a Thermoresponsive Polymer. Tissue Eng Part C Methods 2017; 24:146-157. [PMID: 29239281 DOI: 10.1089/ten.tec.2017.0331] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Human pluripotent stem cells (hPSCs) are viewed as promising candidates for applications in regenerative medicine and therapy due to their proliferative and pluripotent properties. However, obtaining clinically significant numbers of hPSCs remains a limiting factor and impedes their use in therapeutic applications. Conventionally, hPSCs are cultured on two-dimensional surfaces coated with a suitable substrate, such as Matrigel™. This method, however, requires a large surface area to generate sufficient cell numbers to meet clinical needs and is therefore impractical as a manufacturing platform for cell expansion. In addition, the use of enzymes for cell detachment and small molecule inhibitors to increase plating efficiency may impact future cell behavior when used for routine subculturing. In this study, we describe a protocol to generate and maintain hPSC aggregates in a three-dimensional suspension culture by utilizing thermoresponsive nanobridges. The property of the polymer used in the nanobridges enables passaging and expansion through a temperature change in combination with mechanically applied shear to dissociate aggregates; thus, we eliminate the need of enzymes or small molecules for cell dissociation and viability, respectively. Utilizing this platform, maintenance of human embryonic stem cells for three continuous passages demonstrated high expression levels in key pluripotent markers.
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Bioactive nano‐fibrous scaffold for vascularized craniofacial bone regeneration. J Tissue Eng Regen Med 2017; 12:e1537-e1548. [DOI: 10.1002/term.2579] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 08/05/2017] [Accepted: 09/23/2017] [Indexed: 01/08/2023]
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Transcription factor ZNF25 is associated with osteoblast differentiation of human skeletal stem cells. BMC Genomics 2016; 17:872. [PMID: 27814695 PMCID: PMC5097439 DOI: 10.1186/s12864-016-3214-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 10/26/2016] [Indexed: 12/29/2022] Open
Abstract
Background The differentiation of human bone marrow derived skeletal stem cells (known as human bone marrow stromal or mesenchymal stem cells, hMSCs) into osteoblasts involves the activation of a small number of well-described transcription factors. To identify additional osteoblastic transcription factors, we studied gene expression of hMSCs during ex vivo osteoblast differentiation. Results Clustering of gene expression, and literature investigation, revealed three transcription factors of interest – ZNF25, ZNF608 and ZBTB38. siRNA knockdown of ZNF25 resulted in significant suppression of alkaline phosphatase (ALP) activity. This effect was not present for ZNF608 and ZBTB38. To identify possible target genes of ZNF25, we analyzed gene expression following ZNF25 siRNA knockdown. This revealed a 23-fold upregulation of matrix metallopeptidase 1 and an 18-fold upregulation of leucine-rich repeat containing G protein-coupled receptor 5 and RAN-binding protein 3-like. We also observed enrichment in extracellular matrix organization, skeletal system development and regulation of ossification in the entire upregulated set of genes. Consistent with its function as a transcription factor during osteoblast differentiation of hMSC, we showed that the ZNF25 protein exhibits nuclear localization and is expressed in osteoblastic and osteocytic cells in vivo. ZNF25 is conserved in tetrapod vertebrates and contains a KRAB (Krueppel-associated box) transcriptional repressor domain. Conclusions This study shows that the uncharacterized transcription factor, ZNF25, is associated with differentiation of hMSC to osteoblasts.
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CD146/MCAM defines functionality of human bone marrow stromal stem cell populations. Stem Cell Res Ther 2016; 7:4. [PMID: 26753846 PMCID: PMC4710006 DOI: 10.1186/s13287-015-0266-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 11/25/2015] [Accepted: 12/17/2015] [Indexed: 01/04/2023] Open
Abstract
Background Identification of surface markers for prospective isolation of functionally homogenous populations of human skeletal (stromal, mesenchymal) stem cells (hMSCs) is highly relevant for cell therapy protocols. Thus, we examined the possible use of CD146 to subtype a heterogeneous hMSC population. Methods Using flow cytometry and cell sorting, we isolated two distinct hMSC-CD146+ and hMSC-CD146− cell populations from the telomerized human bone marrow-derived stromal cell line (hMSC-TERT). Cells were examined for differences in their size, shape and texture by using high-content analysis and additionally for their ability to differentiate toward osteogenesis in vitro and form bone in vivo, and their migrational ability in vivo and in vitro was investigated. Results In vitro, the two cell populations exhibited similar growth rate and differentiation capacity to osteoblasts and adipocytes on the basis of gene expression and protein production of lineage-specific markers. In vivo, hMSC-CD146+ and hMSC-CD146− cells formed bone and bone marrow organ when implanted subcutaneously in immune-deficient mice. Bone was enriched in hMSC-CD146− cells (12.6 % versus 8.1 %) and bone marrow elements enriched in implants containing hMSC-CD146+ cells (0.5 % versus 0.05 %). hMSC-CD146+ cells exhibited greater chemotactic attraction in a transwell migration assay and, when injected intravenously into immune-deficient mice following closed femoral fracture, exhibited wider tissue distribution and significantly increased migration ability as demonstrated by bioluminescence imaging. Conclusion Our studies demonstrate that CD146 defines a subpopulation of hMSCs capable of bone formation and in vivo trans-endothelial migration and thus represents a population of hMSCs suitable for use in clinical protocols of bone tissue regeneration. Electronic supplementary material The online version of this article (doi:10.1186/s13287-015-0266-z) contains supplementary material, which is available to authorized users.
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Molecular characterisation of stromal populations derived from human embryonic stem cells: Similarities to immortalised bone marrow derived stromal stem cells. Bone Rep 2015; 3:32-39. [PMID: 28377964 PMCID: PMC5365211 DOI: 10.1016/j.bonr.2015.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 06/30/2015] [Accepted: 07/14/2015] [Indexed: 01/22/2023] Open
Abstract
Human bone marrow-derived stromal (skeletal) stem cells (BM-hMSC) are being employed in an increasing number of clinical trials for tissue regeneration. A limiting factor for their clinical use is the inability to obtain sufficient cell numbers. Human embryonic stem cells (hESC) can provide an unlimited source of clinical grade cells for therapy. We have generated MSC-like cells from hESC (called here hESC-stromal) that exhibit surface markers and differentiate to osteoblasts and adipocytes, similar to BM-hMSC. In the present study, we used microarray analysis to compare the molecular phenotype of hESC-stromal and immortalised BM-hMSC cells (hMSC-TERT). Of the 7379 genes expressed above baseline, only 9.3% of genes were differentially expressed between undifferentiated hESC-stromal and BM-hMSC. Following ex vivo osteoblast induction, 665 and 695 genes exhibited ≥ 2-fold change (FC) in hESC-stromal and BM-hMSC, respectively with 172 genes common to both cell types. Functional annotation of significantly changing genes revealed similarities in gene ontology between the two cell types. Interestingly, genes in categories of cell adhesion/motility and epithelial–mesenchymal transition (EMT) were highly enriched in hESC-stromal whereas genes associated with cell cycle processes were enriched in hMSC-TERT. This data suggests that while hESC-stromal cells exhibit a similar molecular phenotype to hMSC-TERT, differences exist that can be explained by ontological differences between these two cell types. hESC-stromal cells can thus be considered as a possible alternative candidate cells for hMSC, to be employed in regenerative medicine protocols. hESC-derived MSC-like cells were compared to immortalised BM-MSC. Comparison was performed using microarrays on non-induced and OB induced cells. Analysis demonstrated close hierarchical relationships and molecular phenotypes. 90.7% of genes were similarly expressed in non-induced cells. 73% of OB induced genes for both cell lines correlated with GO ontology analysis.
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Proteomic Validation of Transcript Isoforms, Including Those Assembled from RNA-Seq Data. J Proteome Res 2015; 14:3541-54. [PMID: 25961807 DOI: 10.1021/pr5011394] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Human proteome analysis now requires an understanding of protein isoforms. We recently published the PG Nexus pipeline, which facilitates high confidence validation of exons and splice junctions by integrating genomics and proteomics data. Here we comprehensively explore how RNA-seq transcriptomics data, and proteomic analysis of the same sample, can identify protein isoforms. RNA-seq data from human mesenchymal (hMSC) stem cells were analyzed with our new TranscriptCoder tool to generate a database of protein isoform sequences. MS/MS data from matching hMSC samples were then matched against the TranscriptCoder-derived database, along with Ensembl and the neXtProt database. Querying the TranscriptCoder-derived or Ensembl database could unambiguously identify ∼450 protein isoforms, with isoform-specific proteotypic peptides, including candidate hMSC-specific isoforms for the genes DPYSL2 and FXR1. Where isoform-specific peptides did not exist, groups of nonisoform-specific proteotypic peptides could specifically identify many isoforms. In both the above cases, isoforms will be detectable with targeted MS/MS assays. Unfortunately, our analysis also revealed that some isoforms will be difficult to identify unambiguously as they do not have peptides that are sufficiently distinguishing. We covisualize mRNA isoforms and peptides in a genome browser to illustrate the above situations. Mass spectrometry data is available via ProteomeXchange (PXD001449).
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The Effects of Processed Whole Orange on Post Prandial Glycemic Responses in Healthy Men. J Acad Nutr Diet 2014. [DOI: 10.1016/j.jand.2014.06.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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An update of human mesenchymal stem cell biology and their clinical uses. Arch Toxicol 2014; 88:1069-82. [PMID: 24691703 DOI: 10.1007/s00204-014-1232-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 03/18/2014] [Indexed: 12/13/2022]
Abstract
In the past decade, an increasing urge to develop new and novel methods for the treatment of degenerative diseases where there is currently no effective therapy has lead to the emerging of the cell therapy or cellular therapeutics approach for the management of those conditions where organ functions are restored through transplantation of healthy and functional cells. Stem cells, because of their nature, are currently considered among the most suitable cell types for cell therapy. There are an increasing number of studies that have tested the stromal stem cell functionality both in vitro and in vivo. Consequently, stromal (mesenchymal) stem cells (MSCs) are being introduced into many clinical trials due to their ease of isolation and efficacy in treating a number of disease conditions in animal preclinical disease models. The aim of this review is to revise MSC biology, their potential translation in therapy, and the challenges facing their adaptation in clinical practice.
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Tools to covisualize and coanalyze proteomic data with genomes and transcriptomes: validation of genes and alternative mRNA splicing. J Proteome Res 2013; 13:84-98. [PMID: 24152167 DOI: 10.1021/pr400820p] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Direct links between proteomic and genomic/transcriptomic data are not frequently made, partly because of lack of appropriate bioinformatics tools. To help address this, we have developed the PG Nexus pipeline. The PG Nexus allows users to covisualize peptides in the context of genomes or genomic contigs, along with RNA-seq reads. This is done in the Integrated Genome Viewer (IGV). A Results Analyzer reports the precise base position where LC-MS/MS-derived peptides cover genes or gene isoforms, on the chromosomes or contigs where this occurs. In prokaryotes, the PG Nexus pipeline facilitates the validation of genes, where annotation or gene prediction is available, or the discovery of genes using a "virtual protein"-based unbiased approach. We illustrate this with a comprehensive proteogenomics analysis of two strains of Campylobacter concisus . For higher eukaryotes, the PG Nexus facilitates gene validation and supports the identification of mRNA splice junction boundaries and splice variants that are protein-coding. This is illustrated with an analysis of splice junctions covered by human phosphopeptides, and other examples of relevance to the Chromosome-Centric Human Proteome Project. The PG Nexus is open-source and available from https://github.com/IntersectAustralia/ap11_Samifier. It has been integrated into Galaxy and made available in the Galaxy tool shed.
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Separate developmental programs for HLA-A and -B cell surface expression during differentiation from embryonic stem cells to lymphocytes, adipocytes and osteoblasts. PLoS One 2013; 8:e54366. [PMID: 23349864 PMCID: PMC3548781 DOI: 10.1371/journal.pone.0054366] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 12/11/2012] [Indexed: 02/06/2023] Open
Abstract
A major problem of allogeneic stem cell therapy is immunologically mediated graft rejection. HLA class I A, B, and Cw antigens are crucial factors, but little is known of their respective expression on stem cells and their progenies. We have recently shown that locus-specific expression (HLA-A, but not -B) is seen on some multipotent stem cells, and this raises the question how this is in other stem cells and how it changes during differentiation. In this study, we have used flow cytometry to investigate the cell surface expression of HLA-A and -B on human embryonic stem cells (hESC), human hematopoietic stem cells (hHSC), human mesenchymal stem cells (hMSC) and their fully-differentiated progenies such as lymphocytes, adipocytes and osteoblasts. hESC showed extremely low levels of HLA-A and no -B. In contrast, multipotent hMSC and hHSC generally expressed higher levels of HLA-A and clearly HLA-B though at lower levels. IFNγ induced HLA-A to very high levels on both hESC and hMSC and HLA-B on hMSC. Even on hESC, a low expression of HLA-B was achieved. Differentiation of hMSC to osteoblasts downregulated HLA-A expression (P = 0.017). Interestingly HLA class I on T lymphocytes differed between different compartments. Mature bone marrow CD4(+) and CD8(+) T cells expressed similar HLA-A and -B levels as hHSC, while in the peripheral blood they expressed significantly more HLA-B7 (P = 0.0007 and P = 0.004 for CD4(+) and CD8(+) T cells, respectively). Thus different HLA loci are differentially regulated during differentiation of stem cells.
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Derivation of stromal (skeletal and mesenchymal) stem-like cells from human embryonic stem cells. Stem Cells Dev 2012; 21:3114-24. [PMID: 22612317 DOI: 10.1089/scd.2012.0035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Derivation of bone forming cells (osteoblasts) from human embryonic stem cells (hESCs) is a prerequisite for their use in clinical applications. However, there is no standard protocol for differentiating hESCs into osteoblastic cells. The aim of this study was to identify the emergence of a human stromal (mesenchymal and skeletal) stem cell (hMSC)-like population, known to be osteoblastic cell precursors and to test their osteoblastic differentiation capacity in ex vivo cultures and in vivo. We cultured hESCs in a feeder-free environment using serum replacement and as suspension aggregates (embryoid bodies; hEBs). Over a 20 day developmental period, the hEBs demonstrated increasing enrichment for cells expressing hMSC markers: CD29, CD44, CD63, CD56, CD71, CD73, CD105, CD106, and CD166 as revealed by immunohistochemical staining and flow cytometry (fluorescence-activated cell sorting) analysis. Ex vivo differentiation of hEBs using bone morphogenic protein 2 (BMP2) combined with standard osteoblast induction medium led to weak osteoblastic induction. Conversely, subcutaneous in vivo implantation of day 20 hEBs in immune deficient mice, mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) as an osteoconductive scaffold, revealed bone and cartilage, and fibrous tissue elements after 8 weeks. These tissues were of human origin and there was no evidence of differentiation to nonmesodermal tissues. hEBs implanted in the absence of HA/TCP formed vacuolated tissue containing glandular, fibrous and muscle-like tissue elements. Conversely, implantation of undifferentiated hESCs resulted in the formation of a teratoma containing a mixture of endodermal, mesodermal, and ectodermal tissues. Our study demonstrates that hMSC-like cells can be obtained from hESCs and they can be induced to form skeletal tissues in vivo when combined with HA/TCP. These findings are relevant for tissue engineering and suggest that differentiated hEBs can provide an unlimited source for functional osteogenic cells.
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The crosstalk between transforming growth factor-β1 and delta like-1 mediates early chondrogenesis during embryonic endochondral ossification. Stem Cells 2012; 30:304-13. [PMID: 22102178 DOI: 10.1002/stem.792] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Delta like-1 (Dlk1)/preadipocyte factor-1 (Pref-1)/fetal antigen-1 (FA1) is a novel surface marker for embryonic chondroprogenitor cells undergoing lineage progression from proliferation to prehypertrophic stages. However, mechanisms mediating control of its expression during chondrogenesis are not known. Thus, we examined the effect of a number of signaling molecules and their inhibitors on Dlk1 expression during in vitro chondrogenic differentiation in mouse embryonic limb bud mesenchymal micromass cultures and mouse embryonic fibroblast (MEF) pellet cultures. Dlk1/Pref-1 was initially expressed during mesenchymal condensation and chondrocyte proliferation, in parallel with expression of Sox9 and Col2a1, and was downregulated upon the expression of Col10a1 by hypertrophic chondrocytes. Among a number of molecules that affected chondrogenesis, transforming growth factor-β1 (TGF-β1)-induced proliferation of chondroprogenitors was associated with decreased Dlk1 expression. This effect was abolished by TGF-β signaling inhibitor SB431542, suggesting regulation of Dlk1/FA1 by TGF-β1 signaling in chondrogenesis. TGF-β1-induced Smad phosphorylation and chondrogenesis were significantly increased in Dlk1(-/-) MEF, while they were blocked in Dlk1 overexpressing MEF, in comparison with wild-type MEF. Furthermore, overexpression of Dlk1 or addition of its secreted form FA1 dramatically inhibited TGF-β1-induced Smad reporter activity. In conclusion, our data identified Dlk1/FA1 as a downstream target of TGF-β1 signaling molecule that mediates its function in embryonic chondrogenesis. The crosstalk between TGF-β1 and Dlk1/FA1 was shown to promote early chondrogenesis during the embryonic endochondral ossification process.
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Stable isotope labelling with amino acids in cell culture for human embryonic stem cell proteomic analysis. Methods Mol Biol 2012; 873:297-305. [PMID: 22528364 DOI: 10.1007/978-1-61779-794-1_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The identification and quantitative measurements of proteins in human embryonic stem cells (hESC) is a fast growing interdisciplinary area with an enormous impact on understanding the biology of hESC and the mechanism controlling self-renewal and differentiation. Using a quantitative mass spectroscopic method of stable isotope labelling with amino acids during cell culture (SILAC), we are able to analyse differential expression of proteins from different cellular compartments and to identify intracellular signalling pathways involved in self-renewal and differentiation. In this chapter, we provide a detailed method for creating SILAC media suitable for use in hESC experiments, additionally we describe methods for the isolation of membrane fractions and cytosolic and nuclear/membrane fractions.
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Snorc is a novel cartilage specific small membrane proteoglycan expressed in differentiating and articular chondrocytes. Osteoarthritis Cartilage 2011; 19:1026-35. [PMID: 21624478 DOI: 10.1016/j.joca.2011.04.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/19/2011] [Accepted: 04/30/2011] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Maintenance of chondrocyte phenotype is a major issue in prevention of degeneration and repair of articular cartilage. Although the critical pathways in chondrocyte maturation and homeostasis have been revealed, the in-depth understanding is deficient and novel modifying components and interaction partners are still likely to be discovered. Our focus in this study was to characterize a novel cartilage specific gene that was identified in mouse limb cartilage during embryonic development. METHODS Open access bioinformatics tools and databases were used to characterize the gene, predicted protein and orthologs in vertebrate species. Immunohistochemistry and mRNA expression methodology were used to study tissue specific expression. Fracture callus and limb bud micromass culture were utilized to study the effects of BMP-2 during experimental chondrogenesis. Fusion protein with C-terminal HA-tag was expressed in Cos7 cells, and the cell lysate was studied for putative glycosaminoglycan attachment by digestion with chondroitinase ABC and Western blotting. RESULTS The predicted molecule is a small, 121 amino acids long type I single-pass transmembrane chondroitin sulfate proteoglycan, that contains ER signal peptide, lumenal/extracellular domain with several threonines/serines prone to O-N-acetylgalactosamine modification, and a cytoplasmic tail with a Yin-Yang site prone to phosphorylation or O-N-acetylglucosamine modification. It is highly conserved in mammals with orthologs in all vertebrate subgroups. Cartilage specific expression was highest in proliferating and prehypertrophic zones during development, and in adult articular cartilage, expression was restricted to the uncalcified zone, including chondrocyte clusters in human osteoarthritic cartilage. Studies with experimental chondrogenesis models demonstrated similar expression profiles with Sox9, Acan and Col2a1 and up-regulation by BMP-2. Based on its cartilage specific expression, the molecule was named Snorc, (Small NOvel Rich in Cartilage). CONCLUSION A novel cartilage specific molecule was identified which marks the differentiating chondrocytes and adult articular chondrocytes with possible functions associated with development and maintenance of chondrocyte phenotype.
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Selective isolation and differentiation of a stromal population of human embryonic stem cells with osteogenic potential. Bone 2011; 48:231-41. [PMID: 20869473 DOI: 10.1016/j.bone.2010.09.023] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 09/09/2010] [Accepted: 09/15/2010] [Indexed: 12/16/2022]
Abstract
The derivation of osteogenic cells from human embryonic stem cells (hESC) has been hampered by the absence of easy and reproducible protocols. hESC grown in feeder-free conditions, often show a sub population of fibroblast-like, stromal cells growing between the colonies. Thus, we examined the possibility that these cells represent a population of stromal (mesenchymal) stem cells (hESC-stromal). Two in house derived hES cell lines (Odense3 and KMEB3) as well as an externally derived cell line (Hues8) were transitioned to feeder-free conditions. A sub population of fibroblast-like cells established between the hESC colonies were isolated by selective adherence to hyaluronic acid-coated plates (100 μg/ml) and were characterized using a combination of FACS analysis and staining. The cells were CD44(+), CD29(+), CD73(+), CD166(+), CD146(+), and CD105(+); and, Oct4⁻, CD34⁻, CD45⁻ and CXCR4⁻. When cultured in osteogenic differentiation media, up regulation of osteoblastic lineage markers (DLX5, MSX2, RUNX2, SPARC, ALP, COL1a1, BGLAP, IBSP, DCN, LOX-L4) and production of in vitro mineralized matrix was detected. hESC-stromal cells loaded on a carrier and implanted either subcutaneously or in a critical size calvarial defect in immune deficient mice for 10 weeks, resulted in new bone formation and partial repair of the calvarial defect. In conclusion, hESC-stromal can be isolated from hESC cultures and represent a good source for obtaining cells with osteogenic differentiation potential suitable for regenerative medicine protocols.
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Enhanced differentiation of human embryonic stem cells to mesenchymal progenitors by inhibition of TGF-beta/activin/nodal signaling using SB-431542. J Bone Miner Res 2010; 25:1216-33. [PMID: 20200949 DOI: 10.1002/jbmr.34] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Directing differentiation of human embryonic stem cells (hESCs) into specific cell types using an easy and reproducible protocol is a prerequisite for the clinical use of hESCs in regenerative-medicine procedures. Here, we report a protocol for directing the differentiation of hESCs into mesenchymal progenitor cells. We demonstrate that inhibition of transforming growth factor beta (TGF-beta)/activin/nodal signaling during embryoid body (EB) formation using SB-431542 (SB) in serum-free medium markedly upregulated paraxial mesodermal markers (TBX6, TBX5) and several myogenic developmental markers, including early myogenic transcriptional factors (Myf5, Pax7), as well as myocyte-committed markers [NCAM, CD34, desmin, MHC (fast), alpha-smooth muscle actin, Nkx2.5, cTNT]. Continuous inhibition of TGF-beta signaling in EB outgrowth cultures (SB-OG) enriched for myocyte progenitor cells; markers were PAX7(+) (25%), MYOD1(+) (52%), and NCAM(+) (CD56) (73%). DNA microarray analysis revealed differential upregulation of 117 genes (>2-fold compared with control cells) annotated to myogenic development and function. Moreover, these cells showed the ability to contract (80% of the population) and formed myofibers when implanted intramuscularly in vivo. Interestingly, SB-OG cells cultured in 10% fetal bovine serum (FBS) developed into a homogeneous population of mesenchymal progenitors that expressed CD markers characteristic of mesenchymal stem cells (MSCs): CD44(+) (100%), CD73(+) (98%), CD146(+) (96%), and CD166(+) (88%) with the ability to differentiate into osteoblasts, adipocytes, and chondrocytes in vitro and in vivo. Furthermore, microarray analysis of these cells revealed downregulation of genes related to myogenesis: MYH3 (-167.9-fold), ACTA1 (-161-fold), MYBPH (-139-fold), ACTC (-100.3-fold), MYH8 (-45.5-fold), and MYOT (-41.8-fold) and marked upregulation of genes related to mesoderm-derived cell lineages. In conclusion, our data provides a simple and versatile protocol for directing the differentiation of hESCs into a myogenic lineage and then further into mesenchymal progenitors by blocking the TGF-beta signaling pathway.
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Isolation and Differentiation of Chondrocytic Cells Derived from Human Embryonic Stem Cells Using dlk1/FA1 as a Novel Surface Marker. Stem Cell Rev Rep 2009; 5:353-68. [DOI: 10.1007/s12015-009-9099-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstracts of presentations to the Annual Meetings of the Canadian Association of General Surgeons Canadian Association of Thoracic Surgeons Canadian Hepato-Pancreato-Biliary Society Canadian Society of Surgical Oncology Canadian Society of Colon and Rectal Surgeons: Victoria, BC Sept. 10-13, 2009. Can J Surg 2009; 52:S1-S48. [PMID: 35488397 PMCID: PMC2726442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023] Open
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Identification of a membrane proteomic signature for human embryonic stem cells independent of culture conditions. Stem Cell Res 2008; 1:219-27. [DOI: 10.1016/j.scr.2008.06.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2008] [Revised: 06/25/2008] [Accepted: 06/25/2008] [Indexed: 01/11/2023] Open
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Distinct GAGE and MAGE-A expression during early human development indicate specific roles in lineage differentiation. Hum Reprod 2008; 23:2194-201. [DOI: 10.1093/humrep/den262] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Variations in Humanized and Defined Culture Conditions Supporting Derivation of New Human Embryonic Stem Cell Lines. CLONING AND STEM CELLS 2006; 8:319-34. [PMID: 17196096 DOI: 10.1089/clo.2006.8.319] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The evolution of "humanized" (i.e., free of animal sourced reagents) and ultimately chemically defined culture systems for human embryo stem cell (hESC) isolation and culture is of importance to improving their efficacy and safety in research and therapeutic applications. This can be achieved by integration of a multitude of individual approaches to replace or eliminate specific animal sourced reagents into a single comprehensive protocol. In the present study our objective was to integrate strategies obviating reliance on some of the most poorly defined and path-critical factors associated with hESC derivation, namely the use of animal immune compliment to isolate embryo inner cell mass, and animal sourced serum products and feeder cells to sustain hESC growth and attachment. As a result we report the derivation of six new hESC lines isolated by outgrowth from whole blastocysts on an extracellular matrix substrate of purified human laminin (Ln) with transitional reliance on mitotically inactivated human fibroblast (HDF) feeder cells. With this integrated system hESC lines were isolated using either HDF conditioned medium supplemented with a bovine-sourced serum replacement (bSRM), or a defined serum-free medium (SFM) containing only human sourced and recombinant protein. Further, outgrowth of embryonic cells from whole blastocysts in both media could be achieved for up to 1 week without reliance on feeder cells. All variant conditions sustained undifferentiated cell status, a stable karyotype and the potential to form cells representative of all three germinal lineages in vitro and in vivo, when transitioned off of feeders onto Laminin or Matrigel. Our study thus demonstrates the capacity to integrate derivation strategies eliminating a requirement for animal immune compliment and serum products, with a transitional requirement for human feeder cells. This represents another sequential step in the generation of therapeutic grade stem cells with reduced risk of zoonotic pathogen transmission.
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In VitroandIn VivoDevelopmental Competence of Ovulated andIn VitroMatured Porcine Oocytes Activated by Electrical Activation. CLONING AND STEM CELLS 2003; 5:355-65. [PMID: 14733753 DOI: 10.1089/153623003772032853] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The objective of this study was to evaluate the in vitro and in vivo developmental competence of parthenogenetic (parthenote) pig embryos derived from ovulated and in vitro matured (IVM) oocytes. A total of four experiments were carried out. These demonstrated that the mean blastocyst rates from stimulated ovulated and IVM pig oocytes were not significantly different (61% vs. 46%, p > 0.05) following in vitro culture. Both ovulated and IVM pig parthenotes were able to develop in vivo for 30 days. Parthenote fetuses collected 21 and 30 days post estrus were morphologically normal but significantly smaller and lighter than fertilized controls (p < 0.01). IVM pig parthenotes stopped development around 31 days post estrus.
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Abstract
Mice have been successfully cloned from somatic and embryonic stem (ES) cells using the "Honolulu method." In the present study, different donor oocytes and different culture conditions were compared to evaluate the developmental potential of nuclear transfer embryos reconstructed with an inbred ES cell line HM-1. Oocytes were recovered from two different F1 donors B6D2F1 (C57BL/6 x DBA/2) and B6CBAF1 (C57BL/6 x CBA). There was no effect of oocyte origin on development of cloned embryos to the morulae/blastocyst stage (B6D2F1 44.1% vs. B6CBAF1 45.0%), and the transferred embryos could develop to term. Two culture conditions were compared to show their ability to support development to the morulae/blastocyst stage of reconstructed embryos with B6D2F1 oocytes. The total cell number in the cloned blastocysts cultured in M16 with 20% oxygen was much higher than that observed in CZB with 20% oxygen. Low oxygen concentration during culture of nuclear transfer embryos in CZB medium showed no beneficial effect on pre-implantation development, no embryos developed to term after transfer to surrogate mothers. Our results demonstrated that not only B6D2F1, but B6CBAF1 oocytes, can be used for nuclear transfer. M16 medium is superior for culture of nuclear transfer embryos and low oxygen concentration with CZB medium during culture shows no benefit on development of cloned embryos.
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Abstract
Mice have been successfully cloned from both somatic cells and hybrid embryonic stem (ES) cells. Heterozygosity of the donor ES cell genome has been suggested as a crucial factor for long-term survival of cloned mice. In the present study, an inbred ES cell line, HM-1 (129/Ola), and a well-tested ES cell line, R1 (129/Sv x 129/Sv-CP), were used as donor cells to evaluate the developmental potential of nuclear transfer embryos. We found that ES cell confluence dramatically affects the developmental potential of reconstructed embryos. With the ES cell line HM-1 and 80-90% confluence, 49% of reconstructed embryos developed to the morula/blastocyst stage, 9% of these embryos developed to live pups when transferred to the surrogate mothers, and 5 of 18 live pups survived to adulthood. By contrast, at 60-70% confluence, only 22% of embryos developed to the morula/blastocyst stage, and after transfer, only a single fetus reached term. Consistent with previous reports, the nuclei of R1 ES cells were also shown to direct development to term, but no live pups were derived from cells at later passages (>20). Our results show that the developmental potential of reconstructed embryos is determined by both cell confluence and cell passage. These results also demonstrate that the inbred ES cell line, HM-1, can be used to produce viable cloned mice, although less efficiently than most heterozygous ES cell lines.
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Abstract
Successful cloning by nuclear transfer has been reported with somatic or embryonic stem (ES) cell nucleus injection into enucleated mouse metaphase II oocytes. In this study, we enucleated mouse oocytes at the germinal vesicle (GV) or pro-metaphase I (pro-MI) stage and cultured the cytoplasm to the MII stage. Nuclei from cells of the R1 ES cell line were injected into both types of cytoplasm to evaluate developmental potential of resulting embryos compared to MII cytoplasmic injection. Immunocytochemical staining revealed that a spindle started to organize 30 min after nucleus injection into all three types of cytoplasm. A well-organized bipolar spindle resembling an MII spindle was present in both pro-MI and MII cytoplasm 1 h after injection with ES cells. However, in the mature GV cytoplasm, chromosomes were distributed throughout the cytoplasm and a much bigger spindle was formed. Pseudopronucleus formation was observed in pro-MI and MII cytoplasm after activation treatment. Although no pronucleus formation was found in GV cytoplasm, chromosomes segregated into two groups in response to activation. Only 8.1% of reconstructed embryos with pro-MI cytoplasm developed to the morula stage after culture in CZB medium. In contrast, 53.5% of embryos reconstructed with MII cytoplasm developed to the morula/blastocyst stage, and 5.3% of transferred embryos developed to term. These results indicate that GV material is essential for nucleus remodeling after nuclear transfer.
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Embryo development and establishment of pregnancy after embryo transfer in pigs: coping with limitations in the availability of viable embryos. Reproduction 2002; 123:507-15. [PMID: 11914113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Embryo transfer and pregnancy maintenance strategies in pigs were evaluated with reference to situations in which limited numbers of viable embryos or micromanipulated embryos are available, such as pig cloning. Development of embryos with compromised zona pellucida was compared with development of embryos with intact zona pellucida. Micromanipulation had no effect on blastocyst production rates after development in vivo or in vitro, but development in vivo improved the number of embryos reaching the blastocyst stage. Transfer of embryos with compromised zona pellucida resulted in live piglets. Several hormone treatments to maintain pregnancy were tested in a model in which three embryos were transferred into unmated recipient gilts, compared with transfer of three embryos into mated recipients. None of the hormonal treatments resulted in pregnancy rates of more than 25% at term and no more than 9% of transferred embryos survived, in comparison with 50% of the mated recipients successfully carrying 25% of transferred embryos. Lastly, the developmental potential of parthenogenetic embryos was assessed and 62% of transferred embryos resulted in pregnancies, none of which continued beyond day 55 of gestation. After co-transfer of three fertilized embryos with 55-60 parthenogenetic embryos into each of six recipients, two live piglets were delivered. The results from the present study indicate that transfer of zona pellucida compromised embryos can yield litters of normal piglets. In addition, it was demonstrated in a model system involving the transfer of three fertilized embryos into mature gilts that hormonal pregnancy maintenance strategies support a low proportion of embryos to term. Lastly, the present study shows for the first time a comparably effective but novel alternative for pregnancy maintenance in the pig involving the co-transfer of parthenote embryos.
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Embryo development and establishment of pregnancy after embryo transfer in pigs: coping with limitations in the availability of viable embryos. Reproduction 2002. [DOI: 10.1530/rep.0.1230507] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Embryo transfer and pregnancy maintenance strategies in pigs were evaluated with reference to situations in which limited numbers of viable embryos or micromanipulated embryos are available, such as pig cloning. Development of embryos with compromised zona pellucida was compared with development of embryos with intact zona pellucida. Micromanipulation had no effect on blastocyst production rates after development in vivo or in vitro, but development in vivo improved the number of embryos reaching the blastocyst stage. Transfer of embryos with compromised zona pellucida resulted in live piglets. Several hormone treatments to maintain pregnancy were tested in a model in which three embryos were transferred into unmated recipient gilts, compared with transfer of three embryos into mated recipients. None of the hormonal treatments resulted in pregnancy rates of more than 25% at term and no more than 9% of transferred embryos survived, in comparison with 50% of the mated recipients successfully carrying 25% of transferred embryos. Lastly, the developmental potential of parthenogenetic embryos was assessed and 62% of transferred embryos resulted in pregnancies, none of which continued beyond day 55 of gestation. After co-transfer of three fertilized embryos with 55-60 parthenogenetic embryos into each of six recipients, two live piglets were delivered. The results from the present study indicate that transfer of zona pellucida compromised embryos can yield litters of normal piglets. In addition, it was demonstrated in a model system involving the transfer of three fertilized embryos into mature gilts that hormonal pregnancy maintenance strategies support a low proportion of embryos to term. Lastly, the present study shows for the first time a comparably effective but novel alternative for pregnancy maintenance in the pig involving the co-transfer of parthenote embryos.
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Somatic cell nuclear transfer in the pig: control of pronuclear formation and integration with improved methods for activation and maintenance of pregnancy. Biol Reprod 2002; 66:642-50. [PMID: 11870070 DOI: 10.1095/biolreprod66.3.642] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
To clone a pig from somatic cells, we first validated an electrical activation method for use on ovulated oocytes. We then evaluated delayed versus simultaneous activation (DA vs. SA) strategies, the use of 2 nuclear donor cells, and the use of cytoskeletal inhibitors during nuclear transfer. Using enucleated ovulated oocytes as cytoplasts for fetal fibroblast nuclei and transferring cloned embryos into a recipient within 2 h of activation, a 2-h delay between electrical fusion and activation yielded blastocysts more reliably and with a higher nuclear count than did SA. Comparable rates of development using DA were obtained following culture of embryos cloned from ovulated or in vitro-matured cytoplasts and fibroblast or cumulus nuclei. Treatment of cloned embryos with cytochalasin B (CB) postfusion and for 6 h after DA had no impact on blastocyst development as compared with CB treatment postfusion only. Inclusion of a microtubule inhibitor such as nocodozole with CB before and after DA improved nuclear retention and favored the formation of single pronuclei in experiments using a membrane dye to reliably monitor fusion. However, no improvement in blastocyst development was observed. Using fetal fibroblasts as nuclear donor cells, a live cloned piglet was produced in a pregnancy that was maintained by cotransfer of parthenogenetic embryos.
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Abstract
Sheep fetal development at 35 days of gestation was examined following natural mating, in vitro production (IVP) of fertilized embryos, or somatic cell nuclear transfer (NT). Five crossbred (Blackface x Black Welsh) and four purebred (Black Welsh) fetuses and their associated placentae produced by natural mating were morphologically normal and consistent with each other. From 10 ewes receiving 21 IVP embryos, 17 fetuses (81%) were recovered, and 15 of these (88%) were normal. The NT fetuses were derived from two Black Welsh fetal fibroblast cell lines (BLW1 and 6). Transfer of 21 BLW1 and 22 BLW6 NT embryos into 12 and 11 ewes, respectively, yielded 7 (33%) and 8 (36%) fetuses, respectively. Only three (43%) BLW1 and two (25%) BLW6 NT fetuses were normal, with the rest being developmentally retarded. The NT fetal and placental deficiencies included liver enlargement, dermal hemorrhaging, and lack of placental vascular development reflected by reduced or absent cotyledonary structures. Fibroblasts isolated from normal and abnormal cloned fetuses did not differ in their karyotype from sexually conceived fetuses or nuclear donor cell lines. Our results demonstrate that within the first quarter of gestation, cloned fetuses are characterized by a high incidence of developmental retardation and placental insufficiency. These deficiencies are not linked to gross defects in chromosome number.
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Abstract
OBJECTIVES To evaluate the effect of sucrose solution given by mouth on infant crying times and measures of distress in the immunisation clinic. DESIGN Randomised, double blind, placebo controlled trial of sucrose solution 75% wt/vol v sterile water as a control. SETTING The immunisation clinic of the Women's and Children's Hospital, Adelaide. PATIENTS A total of 107 healthy infants attending for 2, 4, or 6 month immunisations with polio by mouth (Sabin), intramuscular diphtheria, tetanus, and pertussis (DTP), and intramuscular Haemophilus influenzae type b were randomised to receive 2 ml 75% sucrose solution or sterile water by mouth before the two injections. METHODS The duration of infant crying was recorded during and immediately after two intramuscular immunisations and infant distress was assessed by a visual analogue scale (Oucher scores) independently by a nurse and a parent. RESULTS The administration of 2 ml 75% sucrose solution by mouth reduced the infant crying time and Oucher distress scores after immunisation with DTP/H influenzae type b. CONCLUSIONS Infant immunisation by intramuscular injection is a distressing procedure for infants and parents. Sucrose solution at a high concentration reduces infant distress and is safe and clinically useful in this setting.
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Appendix: morphological and molecular characteristics of living human fetuses between Carnegie stages 7 and 23: embryos in the collection. Hum Reprod Update 1997. [DOI: 10.1093/humupd/3.1.79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Midtrimester hemoperitoneum caused by placenta percreta in association with elevated maternal serum alpha-fetoprotein level. Am J Obstet Gynecol 1994; 171:565-6. [PMID: 7520215 DOI: 10.1016/0002-9378(94)90304-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We report a case of hemoperitoneum in the second trimester due to placenta percreta which was associated with an elevated maternal serum alpha-fetoprotein. A 29-year-old woman, gravida 4, para 1-0-2-1, was seen at 17 weeks' gestation with an acute abdomen. Maternal serum alpha-fetoprotein in a sample drawn 1 week previously revealed a value of 5.0 multiples of the median. At laparotomy, placenta percreta was discovered. This case of placenta percreta diagnosed in the second trimester was associated with an elevated maternal serum alpha-fetoprotein level. Physicians counseling patients with unexplained elevated maternal serum alpha-fetoprotein levels should include placenta accreta or percreta in the differential diagnosis and should maintain an awareness of its existence in patients with acute abdomen in pregnancy.
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Abstract
Cytogenetic studies were carried out on 180 oocytes that appeared unfertilized after in-vitro fertilization. The majority of the 135 that were informative had grossly haploid second meiotic metaphases, two were grossly diploid, and five had a variety of different abnormalities. Twenty-one oocytes were abnormally fertilized and included prematurely condensed sperm chromosomes. The frequency of this phenomenon varied according to the stimulation protocol, those oocytes maturing longer in vivo showing less propensity to abnormal fertilizations. Thirteen per cent of the analysable haploid metaphases were hyperhaploid but none contained extra whole chromosomes. The extra components were a single chromatid (one case), or two single chromatids replacing a whole chromosome (four cases). The data suggest that the chromatids arose as a result of premature centromere division at meiosis I, and that this may be a major mechanism for trisomy formation rather than non-disjunction of whole bivalents at meiosis I, as generally believed.
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Abstract
We have previously reported the unusual combination of low urinary free cortisol levels with high urinary norepinephrine excretion in posttraumatic stress disorder (PTSD) patients in comparison with four other patient groups: major depressive disorder, endogenous type; bipolar I, manic; paranoid schizophrenia; undifferentiated schizophrenia. Cortisol levels alone did not distinguish PTSD from paranoid schizophrenia patients and norepinephrine levels alone did not distinguish PTSD from bipolar I, manic, patients. In further consideration of these findings, we have found that combining the values for the two systems in a norepinephrine/cortisol (N/C) ratio provides a measure that significantly distinguishes PTSD from all the other patient groups throughout the hospitalization period. The N/C ratio was more than twice as high in the PTSD group than in all the other patient groups in the first sample following hospital admission, in the mean sample during hospitalization, and in the last sample before discharge. The mean N/C ratio for the PTSD group was 2.54, compared with a mean of .99 for the other four groups, which ranged from .81 to 1.18. The diagnostic sensitivity was 78% and the specificity was 94% for correct classification of PTSD in our sample. These preliminary findings yield further encouragement for exploring multivariate strategies, using hormonal ratios or profiles, in an effort to increase the diagnostic sensitivity of neuroendocrine criteria in the assessment of psychiatric patients.
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Performance standards for social workers. SOCIAL WORK 1988; 33:339-344. [PMID: 10288324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
Urinary norepinephrine and epinephrine levels (microgram/day) were measured at two-week intervals during the course of hospitalization in the following patient groups: post-traumatic stress disorder (PTSD); major depressive disorder (MDD); bipolar I, manic (BP); paranoid schizophrenia (PS); and undifferentiated schizophrenia (US). The mean norepinephrine level during hospitalization was significantly higher in PTSD (76 +/- 10.4 micrograms/day) than in BP (60.6 +/- 8.4 micrograms/day), MDD (41.2 +/- 4.7 micrograms/day), PS (33.4 +/- 4.9 micrograms/day) and US (34.3 +/- 5.9 micrograms/day) groups, according to Duncan's multiple range test, (F(4,39) = 6.94, p less than 0.0003). The norepinephrine elevations in the PTSD group were sustained throughout hospitalization. The only other group to show mean levels in this range was the BP group in the first sample after hospital admission. This finding supports prior psychophysiological studies indicating increased sympathetic nervous system activity in PTSD patients. The mean epinephrine level during hospitalization was also significantly higher in PTSD (22.7 +/- 2.4 micrograms/day) than in MDD (13.6 +/- 1.7 micrograms/day), PS (14.7 +/- 2.4 micrograms/day), and US (18.9 +/- 1.8 micrograms/day), but not higher than in BP (21.5 +/- 2.7 micrograms/day). The relationship of epinephrine levels among diagnostic groups was sustained throughout hospitalization. It appears likely that the main underlying mechanisms for elevations of both hormones are psychological, but further work will be required to establish the exact nature of these mechanisms.
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Abstract
Norepinephrine and epinephrine were measured serially in 24-hour urine collections from 99 male psychiatric inpatients with mixed diagnoses. The group was blindly divided into those with a previous history of at least one suicide attempt (N = 38) and those without such a history (N = 61). The ratio of norepinephrine-to-epinephrine levels was significantly lower in the group with a history of suicide attempts. The authors discuss the possibility that a low norepinephrine-to-epinephrine ratio is a risk factor for suicidal behavior.
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Abstract
The inter-rater reliability of a schedule used to assess personality disorders was examined. The Personality Assessment Schedule (PAS) involves an interview with both the patient and a close informant and the ratings for the informant are given most weight in the final scoring. Videotaped interviews with 23 psychiatric patients, most of whom had a clinical diagnosis of personality disorder, and a close informant were scored by seven raters, four in the United Kingdom and three in the United States. Overall inter-rater reliabilities (using the intraclass correlation coefficient, RI) were generally good to excellent for each of the 24 personality variables tested, ranging between .66 and .94 for informants and between .51 and .91 for subjects. Corresponding reliability coefficients for overall mean PAS scores were .82 and .75, respectively. Consistent with these findings, there was little bias between the scores of American and British raters, although there was some tendency for American raters to score higher for the trait of eccentricity and lower for the trait of conscientiousness than was true for British raters. There was less bias for informants' ratings than for those of subjects. In a second set of analyses, it was shown that inter-rater reliability levels (using the Kappa statistic) were also good to excellent (.6 to .8) for the categorical diagnosis of personality disorder. These results, taken together, demonstrate that abnormal personality can be reliably assessed by both British and American raters.
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Assessing treatment response to the monoamine oxidase inhibitor isocarboxazid. J Clin Psychiatry 1984; 45:44-8. [PMID: 6376484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The response to the MAOI isocarboxazid was investigated in a two-phase protocol. Phase 1 was a double-blind, placebo-controlled study; Phase 2 was an open active medication trial for Phase 1 placebo patients who still met symptom criteria. In Phase 1, 60 male outpatients were randomly divided into placebo or active medication groups. Mean platelet MAO inhibition was 86% by Week 1, while significant symptomatic improvement was not seen until Week 3. In Phase 2, 16 of the symptomatic placebo patients were given an open trial on isocarboxazid; thus, 43 patients received a trial of active medication. Separation of responders (N = 26) from nonresponders (N = 17) by discriminant function analysis using 3 entry variables (platelet MAO activity, standing diastolic blood pressure, and psychomotor irregularity) accounted for 28% of the variance, with correct classification of 32 of the 43 patients.
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Abstract
Three of 22 subjects in a study of neuroendocrine correlates of clinical change made serious suicide attempts, 2 of which were lethal. The suicidal subjects had significantly higher 24-hour urinary cortisol levels and significantly lower 24-hour urinary norepinephrine-to-epinephrine ratios than the nonsuicidal patients had. Although the cortisol finding confirms earlier reports, the norepinephrine-to-epinephrine ratio finding is new. The results support the concept that the clinical utility of neuroendocrine measures is enhanced by using a multihormonal profile.
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Chronic depression: response to amitriptyline after discontinuation. Biol Psychiatry 1982; 17:913-7. [PMID: 6810962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Abstract
In this study 10 of 17 patients receiving long-term amitriptyline treatment (average duration: 3.7 years, average dose: 138 mg) had their medication tapered and discontinued under double-blind conditions. Eight became depressed within 3 to 15 weeks. None of the 7 control subjects became depressed during the 6 months of the study. Those who became depressed also showed psychomotor retardation and sleep disturbance. Relief of longstanding anticholinergic side effects followed medication discontinuation. Some patients whose amitryptyline was discontinued experienced a mild withdrawal syndrome within the first 2 weeks, consisting of irritability, dream and sleep disturbance, and restlessness during the first few weeks.
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Abstract
Double-blind, placebo-controlled trials have documented the efficacy of some monoamine oxidase (MAO) inhibitors in treating certain depressed patients. This preliminary report of a 6-week, double-blind, placebo-controlled study of the MAO inhibitor isocarboxazid (Marplan) examines the time course of platelet MAO inhibition and treatment response, and describes symptoms that distinguish markedly improved from slightly improved responders. Thirty male outpatients, ages 28-64, randomly divided into placebo (n = 15) and active medication (n = 15) groups, were followed weekly. Medication was started at 20 mg daily and increased to achieve 90% platelet MAO inhibition. Data were analyzed for 24 patients who completed at least 3 weeks of the study. A clinician's global change rating at the study's conclusion showed that 12 of 13 patients (92%) in the active medication group improved, while 3 of 11 (27%) patients in the placebo group improved. Significant symptomatic improvement occurred in the active treatment group by week 3. Trends suggest that anxiety improved first (week 2), followed by depression (week 3), and finally cognitive outlook (week 6). Only minimal difficulties were observed with orthostatic hypotension, hypertensive crises, or other side effects. At baseline, the only significant difference between the markedly improved and slightly improved groups was greater psychomotor retardation in the markedly improved group. Trends suggest that the markedly improved group showed less depression, anxiety, sleep disturbance, and weight loss, fewer gastrointestinal complaints, and more helplessness and worthlessness.
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