- Email: [email protected]
P14. Extracellular matrix deposition and function in the early chick embryo
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Abstract / Differentiation 80 (2010) S17–S63
P14 Extracellular matrix deposition and function in the early chick embryo
P. Rifes a,b, M. Val-Flores a, G.M. Martins a,b, S. Thorsteinsdo´ttir a,b a
Departamento de Biologia Animal e Centro de Biologia Ambiental, Faculdade de Ciˆencias da Universidade de Lisboa, Lisbon, Portugal b Instituto Gulbenkian de Ciˆencia, Oeiras, Portugal E-mail address: [email protected] (P. Rifes)
Cells within all multicellular organisms are surrounded by a heterogeneous mixture of macromolecules, collectively known as the extracellular matrix (ECM). The ECM is synthesised and organised by cells, providing them with a substrate to interact with, spaces to migrate through and cell–ECM engagement also directly impacts cell polarisation, proliferation, survival and differentiation. ECM molecules are present from the earliest stages of embryo development and the developmentally regulated dynamics of ECM assembly and degradation play key roles in many embryological processes. In this study we addressed how fibronectin, laminin and chondroitin sulphate proteoglycans are deposited in the early (HH12–15) chick embryo, focusing on the developing mesodermal regions and the neural tube. We find that fibronectin is the first ECM molecule to form a complex ECM. Although present in the interstitial space, fibrillar fibronectin matrices are more prominent lining epithelioid (somites, notochord and intermediate mesoderm) and epithelial (neural tube) tissues, before any assembled basement membrane is detected. However, as these epithelioid/epithelial tissues develop, laminin is progressively assembled on their surface. Assembly starts in small patches localized in fibronectin-poor areas and with developmental time, these patches grow in size until the tissues are lined with a laminin basement membrane. Inhibition of fibronectin assembly leads to abnormal cell polarization and containment, suggesting that the fibronectin matrix is essential for the initial epithelial development of these tissues, before the appearance of the basement membrane. Although the interstitial spaces of HH12–15 embryos are only partially filled with a fibronectin matrix, we find that chondroitin sulphate proteoglycans are progressively deposited in these spaces and appear to play a role in separating the early tissue units. In agreement with this, treatment of cultured chick embryo explants with chondroitinase ABC leads to the collapse of all extracellular space and to mesodermal tissue deformations. We conclude that fibronectin matrices play an important role in polarizing cells and containing cell movements in young epithelia before a laminin-containing basement membrane forms, while chondroitin sulphate proteoglycans are crucial for maintaining interstitial spaces. The developmental deposition of these ECMs is thus essential for the correct morphogenesis of the early embryo. doi: 10.1016/j.diff.2010.09.020
P15 Statistical analysis of heterogeneous motility of embryonic stem cells under a microfluidic flow
Seul Ki Min, Byung Man Lee, Sung Hoon Kim, Chung Hwan Shin, Hwa Sung Shin Department of Biological Engineering, Inha University, Incheon 402-751, Republic of Korea E-mail address: [email protected] (H.S. Shin) Cell membrane motility describes cellular dynamics such as adhesion, extension and migration, pertaining to intracellular
molecular dynamics. Therefore, cell shape and motility have been identified as key features on cellular physicochemistry. We suggested the free peripheral membrane length ratio (Lfr) as a new parameter and ANOVA-incorporated analysis strategy to characterize cell’s shape and motility. Lfr means the ratio of free peripheral membrane length unattached by other cells (Lf) to the cell’s peripheral length. With the help of statistical analysis of embryonic stem cell membrane motilities under a microfluidic flow, we demonstrated Lfr has a positive correlation with cellular area (Ar) and Lf but negative correlation with cellular roundness (Rn).
Acknowledgement This work was supported by INHA UNIVERSITY Research Grant (INHA-40875). doi: 10.1016/j.diff.2010.09.021
P16 Retract doi: 10.1016/j.diff.2010.09.022
P17 Comparative investigation of aged human mesenchymal stem cells on defined self-assembled monolayer (SAM) surfaces
Sung Hoon Kim, Seul Ki Min, Byung Man Lee, Chung Hwan Shin, Hwa Sung Shin Department of Biological Engineering, Inha University, Incheon 402-751, Republic of Korea E-mail address: [email protected] (H.S. Shin) Recently, human mesenchymal stem cells (hMSC) have been investigated as cell sources for tissue engineering or cell therapy. Compared with embryonic stem cell, they have advantaged properties given that they can address allorecognition risk and ethical problem. In vitro cultured hMSCs gradually lose their potential of differentiation and self-renewal. A large of reports about MSC deal with early-passage cells. However, this research is for investigating late-passage hMSCs on several functionalized substrate. Selfassembled monolayer is a model system which is well defined, easily replicated and well-characterized surface presenting a several of chemical moieties. Aged hMSC morphology and its heterogeneity are modulated by surface energy. hMSCs on high surface energy substrate show higher rate of adhesion but lower homogeneity than those on low surface energy substrate. These results suggest lots of information in designing scaffolds for tissue engineering or to make adaptive environment in implantation.
Acknowledgement This work was supported by INHA UNIVERSITY Research Grant (INHA-40875). doi: 10.1016/j.diff.2010.09.023
Abstract / Differentiation 80 (2010) S17–S63
P14 Extracellular matrix deposition and function in the early chick embryo
P. Rifes a,b, M. Val-Flores a, G.M. Martins a,b, S. Thorsteinsdo´ttir a,b a
Departamento de Biologia Animal e Centro de Biologia Ambiental, Faculdade de Ciˆencias da Universidade de Lisboa, Lisbon, Portugal b Instituto Gulbenkian de Ciˆencia, Oeiras, Portugal E-mail address: [email protected] (P. Rifes)
Cells within all multicellular organisms are surrounded by a heterogeneous mixture of macromolecules, collectively known as the extracellular matrix (ECM). The ECM is synthesised and organised by cells, providing them with a substrate to interact with, spaces to migrate through and cell–ECM engagement also directly impacts cell polarisation, proliferation, survival and differentiation. ECM molecules are present from the earliest stages of embryo development and the developmentally regulated dynamics of ECM assembly and degradation play key roles in many embryological processes. In this study we addressed how fibronectin, laminin and chondroitin sulphate proteoglycans are deposited in the early (HH12–15) chick embryo, focusing on the developing mesodermal regions and the neural tube. We find that fibronectin is the first ECM molecule to form a complex ECM. Although present in the interstitial space, fibrillar fibronectin matrices are more prominent lining epithelioid (somites, notochord and intermediate mesoderm) and epithelial (neural tube) tissues, before any assembled basement membrane is detected. However, as these epithelioid/epithelial tissues develop, laminin is progressively assembled on their surface. Assembly starts in small patches localized in fibronectin-poor areas and with developmental time, these patches grow in size until the tissues are lined with a laminin basement membrane. Inhibition of fibronectin assembly leads to abnormal cell polarization and containment, suggesting that the fibronectin matrix is essential for the initial epithelial development of these tissues, before the appearance of the basement membrane. Although the interstitial spaces of HH12–15 embryos are only partially filled with a fibronectin matrix, we find that chondroitin sulphate proteoglycans are progressively deposited in these spaces and appear to play a role in separating the early tissue units. In agreement with this, treatment of cultured chick embryo explants with chondroitinase ABC leads to the collapse of all extracellular space and to mesodermal tissue deformations. We conclude that fibronectin matrices play an important role in polarizing cells and containing cell movements in young epithelia before a laminin-containing basement membrane forms, while chondroitin sulphate proteoglycans are crucial for maintaining interstitial spaces. The developmental deposition of these ECMs is thus essential for the correct morphogenesis of the early embryo. doi: 10.1016/j.diff.2010.09.020
P15 Statistical analysis of heterogeneous motility of embryonic stem cells under a microfluidic flow
Seul Ki Min, Byung Man Lee, Sung Hoon Kim, Chung Hwan Shin, Hwa Sung Shin Department of Biological Engineering, Inha University, Incheon 402-751, Republic of Korea E-mail address: [email protected] (H.S. Shin) Cell membrane motility describes cellular dynamics such as adhesion, extension and migration, pertaining to intracellular
molecular dynamics. Therefore, cell shape and motility have been identified as key features on cellular physicochemistry. We suggested the free peripheral membrane length ratio (Lfr) as a new parameter and ANOVA-incorporated analysis strategy to characterize cell’s shape and motility. Lfr means the ratio of free peripheral membrane length unattached by other cells (Lf) to the cell’s peripheral length. With the help of statistical analysis of embryonic stem cell membrane motilities under a microfluidic flow, we demonstrated Lfr has a positive correlation with cellular area (Ar) and Lf but negative correlation with cellular roundness (Rn).
Acknowledgement This work was supported by INHA UNIVERSITY Research Grant (INHA-40875). doi: 10.1016/j.diff.2010.09.021
P16 Retract doi: 10.1016/j.diff.2010.09.022
P17 Comparative investigation of aged human mesenchymal stem cells on defined self-assembled monolayer (SAM) surfaces
Sung Hoon Kim, Seul Ki Min, Byung Man Lee, Chung Hwan Shin, Hwa Sung Shin Department of Biological Engineering, Inha University, Incheon 402-751, Republic of Korea E-mail address: [email protected] (H.S. Shin) Recently, human mesenchymal stem cells (hMSC) have been investigated as cell sources for tissue engineering or cell therapy. Compared with embryonic stem cell, they have advantaged properties given that they can address allorecognition risk and ethical problem. In vitro cultured hMSCs gradually lose their potential of differentiation and self-renewal. A large of reports about MSC deal with early-passage cells. However, this research is for investigating late-passage hMSCs on several functionalized substrate. Selfassembled monolayer is a model system which is well defined, easily replicated and well-characterized surface presenting a several of chemical moieties. Aged hMSC morphology and its heterogeneity are modulated by surface energy. hMSCs on high surface energy substrate show higher rate of adhesion but lower homogeneity than those on low surface energy substrate. These results suggest lots of information in designing scaffolds for tissue engineering or to make adaptive environment in implantation.
Acknowledgement This work was supported by INHA UNIVERSITY Research Grant (INHA-40875). doi: 10.1016/j.diff.2010.09.023