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Claire E Kendalwright - One of the best experts on this subject based on the ideXlab platform.
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pre b cell colony enhancing factor pbef nampt visfatin and vascular endothelial growth factor vegf cooperate to increase the permeability of the human placental Amnion
Placenta, 2013Co-Authors: J M Astern, Abby C Collier, Claire E KendalwrightAbstract:Fluid efflux across the region of the Amnion overlying the placenta is an essential component of the intramembranous absorption pathway that maintains amniotic fluid volume homeostasis. Dysregulation of this pathway may result in adverse pregnancy outcomes, however the factors controlling Amnion permeability are unknown. Here, we report a novel mechanism that increases placental Amnion permeability. Pre-B Cell Colony Enhancing Factor (PBEF) is a stress-responsive cytokine expressed by the human Amnion, and is known to induce Vascular Endothelial Growth Factor (VEGF) production by other cell types. Interestingly, VEGF is up-regulated in the ovine Amnion when intramembranous absorption is augmented. In this study, we show that PBEF induced VEGF secretion by primary human amniotic epithelial cells (AEC) derived from the placental Amnion, as well as from the reflected Amnion that lines the remainder of the gestational sac. Further, PBEF treatment led to the increased expression of VEGFR2 in placental AEC, but not reflected AEC. To test the hypothesis that PBEF and VEGF increase placental Amnion permeability, we monitored the transfer of 2′,7′-dichlorofluorescein (DCF) from the fetal to the maternal side of human Amnion explants. A treatment regimen including both PBEF and VEGF increased the rate of DCF transfer across the placental Amnion, but not the reflected Amnion. In summary, our results suggest that by augmenting VEGFR2 expression in the placental Amnion, PBEF primes the tissue for a VEGF-mediated increase in permeability. This mechanism may have important implications in amniotic fluid volume control throughout gestation.
Paulo N G Pereira - One of the best experts on this subject based on the ideXlab platform.
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amniotic ectoderm expansion in mouse occurs via distinct modes and requires smad5 mediated signalling
Development, 2018Co-Authors: Mariya P Dobreva, Kirstie A Lawson, Vanesa Abon Escalona, Marina Naval Sanchez, Ljuba C Ponomarev, Paulo N G Pereira, Agata Stryjewska, Nathan Criem, Danny Huylebroeck, Susana LopesAbstract:Upon gastrulation, the mammalian conceptus transforms rapidly from a simple bilayer into a multilayered embryo enveloped by its extra-embryonic membranes. Impaired development of the Amnion, the innermost membrane, causes major malformations. To clarify the origin of the mouse Amnion, we used single-cell labelling and clonal analysis. We identified four clone types with distinct clonal growth patterns in amniotic ectoderm. Two main types have progenitors in extreme proximal-anterior epiblast. Early descendants initiate and expand amniotic ectoderm posteriorly, while descendants of cells remaining anteriorly later expand amniotic ectoderm from its anterior side. Amniogenesis is abnormal in embryos deficient in the bone morphogenetic protein (BMP) signalling effector SMAD5, with delayed closure of the proamniotic canal, and aberrant Amnion and folding morphogenesis. Transcriptomics of individual Smad5 mutant Amnions isolated before visible malformations and tetraploid chimera analysis revealed two Amnion defect sets. We attribute them to impairment of progenitors of the two main cell populations in amniotic ectoderm and to compromised cuboidal-to-squamous transition of anterior amniotic ectoderm. In both cases, SMAD5 is crucial for expanding amniotic ectoderm rapidly into a stretchable squamous sheet to accommodate exocoelom expansion, axial growth and folding morphogenesis.
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Amniotic ectoderm expansion in mouse occurs via distinct modes and requires SMAD5-mediated signalling
'The Company of Biologists', 2018Co-Authors: Dobreva Mariya P, Paulo N G Pereira, Huylebroeck Danny, Lawson, Kirstie A, Escalona, Vanesa Abon, Sanchez, Marina N, Ponomarev, Ljuba C, Stryjewska Agata, Criem Nathan, Lopes, Susana Chuva M De SousaAbstract:Upon gastrulation, the mammalian conceptus transforms rapidly from a simple bilayer into a multilayered embryo enveloped by its extra-embryonic membranes. Impaired development of the Amnion, the innermost membrane, causes major malformations. To clarify the origin of the mouse Amnion, we used single-cell labelling and clonal analysis. We identified four clone types with distinct clonal growth patterns in amniotic ectoderm. Two main types have progenitors in extreme proximal-anterior epiblast. Early descendants initiate and expand amniotic ectoderm posteriorly, while descendants of cells remaining anteriorly later expand amniotic ectoderm from its anterior side. Amniogenesis is abnormal in embryos deficient in the bone morphogenetic protein (BMP) signalling effector SMAD5, with delayed closure of the proamniotic canal, and aberrant Amnion and folding morphogenesis. Transcriptomics of individual Smad5 mutant Amnions isolated before visible malformations and tetraploid chimera analysis revealed two Amnion defect sets. We attribute them to impairment of progenitors of the two main cell populations in amniotic ectoderm and to compromised cuboidal-to-squamous transition of anterior amniotic ectoderm. In both cases, SMAD5 is crucial for expanding amniotic ectoderm rapidly into a stretchable squamous sheet to accommodate exocoelom expansion, axial growth and folding morphogenesis.status: publishe
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RESEARCH ARTICLE Open Access
2013Co-Authors: Paulo N G Pereira, Kirstie A Lawson, Mariya P Dobreva, Danny Huylebroeck, Liz Graham, An ZwijsenAbstract:Background: Despite the detailed knowledge obtained over the last decade on the molecular regulation of gastrulation in amniotes, the process of Amnion development has been poorly described and illustrated in mice, and conflicting descriptions exist. Understanding the morphogenesis and development not only of the early mouse embryo, but also of its extraembryonic tissues, is crucial for correctly interpreting fate-mapping data and mouse mutants with gastrulation defects. Moreover, the recent isolation from Amnion of cells with stem cell features further argues for a better understanding of the process of Amnion formation. Here, we revisit the highly dynamic process of Amnion formation in the mouse. Amnion development starts early during gastrulation and is intimately related to the formation of the exocoelom and the expansion of the amniotic fold. The authoritative description involves the fusion of two amniotic folds, a big posterior and a smaller anterior fold. We challenged this ‘two amniotic folds ’ model by performing detailed histomorphological analyses of dissected, staged embryos and 3D reconstructions using historical sections. Results: A posterior fold of extraembryonic ectoderm and associated epiblast is formed early during gastrulation by accumulation of extraembryonic mesoderm posterior to the primitive streak. Previously called the “posterior amniotic fold”, we rename it the “amniochorionic fold ” (ACF) because it forms both Amnion and chorion. Exocoelom formatio
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Periostin as a biomarker of the amniotic membrane.
Stem Cells International, 2012Co-Authors: Mariya P Dobreva, Paulo N G Pereira, Larissa Lhoest, Lieve Umans, Anne Camus, Susana M Chuva De Sousa Lopes, An ZwijsenAbstract:Tracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse.
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Periostin as a biomarker of the amniotic membrane
'Hindawi Limited', 2012Co-Authors: Dobreva Mariya, Paulo N G Pereira, Lhoest Larissa, Umans Lieve, Chuva De Sousa Lopes, Susana M, An ZwijsenAbstract:Tracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse.status: publishe
Marek Sarisský - One of the best experts on this subject based on the ideXlab platform.
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isolation and basic characterization of human term Amnion and chorion mesenchymal stromal cells
Cytotherapy, 2011Co-Authors: Darina Bacenkova, Jan Rosocha, Timea Tothova, Ladislav Rosocha, Marek SarisskýAbstract:Background aims. Emerging evidence suggests human placental membrane is a valuable source of mesenchymal stromal cells (MSC). Amnion and chorion are tissues of early embryologic origin that may entail progenitor potential. These tissues are abundantly available and ethically unobjectionable and, because they are discarded post-partum, they can be widely used for extensive research and eventually for therapeutic studies. Methods. We looked at the cells isolated from the six Amnions and chorions of term placentas of gestational weeks 39 1. Isolated cells were characterized by morphologic and immunophenotypic analysis. Results. With fl ow cytometry immunophenotype analysis, Amnion- and chorion-derived cells were positive for MSC markers, and negative for hematopoietic markers. Immunocytochemical staining was positive for the embryonic cell markers Oct-3/4 and Rex-1. Oct-3/4 is a POU transcription factor that is expressed in embryonic stem (ES) cells and germ cells, and its expression is required to sustain cell self-renewal and pluripotency. Oct-3/4 is the most recognized marker for totipotent ES cells. Rex-1 is a zinc fi nger family transcription factor that is highly expressed in embryonic stem cells. It is one of several gene markers used to identify undifferentiated stem cells, and its expression is downregulated upon stem cell differentiation. Amnion- and chorion-derived cells were capable, under differentiation conditions, to differentiate into to mesoderm lineages. Conclusions. Phenotypic studies indicate MSC-like profi les in both Amnion- and chorion-derived cells. Cells in vitro had fi broblastoid morphology. The in vitro growth behavior of such placenta-derived progenitor cells was similar to that of bone marrow MSC. Our results indicate that MSC can be easily isolated from the human term placenta. The human amniotic and chorion MSC maintained a marker profi le similar to the mesenchymal progenitors and could be used for studies as an alternative source of MSC for further application in cellular therapy.
An Zwijsen - One of the best experts on this subject based on the ideXlab platform.
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doi:10.1155/2012/987185 Research Article Periostin as a Biomarker of the Amniotic Membrane
2016Co-Authors: An ZwijsenAbstract:License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Tracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the differen
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RESEARCH ARTICLE Open Access
2013Co-Authors: Paulo N G Pereira, Kirstie A Lawson, Mariya P Dobreva, Danny Huylebroeck, Liz Graham, An ZwijsenAbstract:Background: Despite the detailed knowledge obtained over the last decade on the molecular regulation of gastrulation in amniotes, the process of Amnion development has been poorly described and illustrated in mice, and conflicting descriptions exist. Understanding the morphogenesis and development not only of the early mouse embryo, but also of its extraembryonic tissues, is crucial for correctly interpreting fate-mapping data and mouse mutants with gastrulation defects. Moreover, the recent isolation from Amnion of cells with stem cell features further argues for a better understanding of the process of Amnion formation. Here, we revisit the highly dynamic process of Amnion formation in the mouse. Amnion development starts early during gastrulation and is intimately related to the formation of the exocoelom and the expansion of the amniotic fold. The authoritative description involves the fusion of two amniotic folds, a big posterior and a smaller anterior fold. We challenged this ‘two amniotic folds ’ model by performing detailed histomorphological analyses of dissected, staged embryos and 3D reconstructions using historical sections. Results: A posterior fold of extraembryonic ectoderm and associated epiblast is formed early during gastrulation by accumulation of extraembryonic mesoderm posterior to the primitive streak. Previously called the “posterior amniotic fold”, we rename it the “amniochorionic fold ” (ACF) because it forms both Amnion and chorion. Exocoelom formatio
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Periostin as a biomarker of the amniotic membrane.
Stem Cells International, 2012Co-Authors: Mariya P Dobreva, Paulo N G Pereira, Larissa Lhoest, Lieve Umans, Anne Camus, Susana M Chuva De Sousa Lopes, An ZwijsenAbstract:Tracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse.
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Periostin as a biomarker of the amniotic membrane.
'Hindawi Limited', 2012Co-Authors: Dobreva Mariya P, Lhoest Larissa, Pereira, Paulo N G, Umans Lieve, Camus Anne, Chuva De Sousa Lopes, Susana M, An ZwijsenAbstract:International audienceTracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse
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Periostin as a biomarker of the amniotic membrane
'Hindawi Limited', 2012Co-Authors: Dobreva Mariya, Paulo N G Pereira, Lhoest Larissa, Umans Lieve, Chuva De Sousa Lopes, Susana M, An ZwijsenAbstract:Tracing the precise developmental origin of Amnion and Amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in Amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP) target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early Amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn) mRNA enrichment in Amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse.status: publishe
Andreas H. Zisch - One of the best experts on this subject based on the ideXlab platform.
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comparative characterization of cultured human term Amnion epithelial and mesenchymal stromal cells for application in cell therapy
Cell Transplantation, 2008Co-Authors: Grozdana Bilic, Ajit S Mallik, Steffen M Zeisberger, Roland Zimmermann, Andreas H. ZischAbstract:Emerging evidence suggests human Amnion tissue as a valuable source of two distinct types of pluripotent cells, Amnion epithelial cells (hAECs) and mesenchymal stromal cells (hAMSCs), for applications in cell replacement therapy. For some approaches, it may be necessary to culture and differentiate these cells before they can be transplanted. No systematic attempt has been yet made to determine the quantity and quality of Amnion cells after isolation and culture. We looked at Amnion cell isolates from 27 term placentas. Following our optimized protocol, primary yields were 6.3 x 10(6) hAECs and 1.7 x 10(6) hAMSCs per gram Amnion. All 27 cases gave vital cultures of hAMSCs, while one third of cases (9 of 27) failed to give adherent cultures of hAECs. Primary cultures contained significantly more proliferating than apoptotic cells (hAECs: 16.4% vs. 4.0%; hAMSCs: 9.5% vs. 2.4%). Neither hAECs nor hAMSCs were clonogenic. They showed slow proliferation that almost stopped beyond passage 5. Microscopic follow-up revealed that hAEC morphology gradually changed towards mesenchymal phenotype over several passages. Flow cytometric characterization of primary cultures showed expression of mesenchymal progenitor markers CD73, CD90, CD105, and CD166, as well as the embryonic stem cell markers SSEA-3 and -4 on both Amnion cell types. These profiles were grossly maintained in secondary cultures. Reverse transcriptase-PCR analysis exhibited transcripts of Oct-3/4 and stem cell factor in primary and secondary cultures of all cases, but no telomerase reverse transcriptase. Immunocytochemistry confirmed translation into Oct-3/4 protein in part of hAEC cultures, but not in hAMSCs. Further, both Amnion cell types stained for CD90 and SSEA-4. Osteogenic induction studies with Amnion cells from four cases showed significantly stronger differentiation of hAECs than hAMSCs; this capacity to differentiate greatly varied between cases. In conclusion, hAECs and hAMSCs in culture exhibit and maintain a similar marker profile of mesenchymal progenitors. hAECs were found as a less reliable source than hAMSCs and altered morphology during subculture.