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Shahin Rafii - One of the best experts on this subject based on the ideXlab platform.

  • Mobilization of Endothelial and Hematopoietic Stem and Progenitor Cells by Adenovector‐Mediated Elevation of Serum Levels of SDF‐1, VEGF, and Angiopoietin‐1
    Annals of the New York Academy of Sciences, 2011
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

  • mobilization of Endothelial and hematopoietic Stem and progenitor Cells by adenovector mediated elevation of serum levels of sdf 1 vegf and angiopoietin 1
    Annals of the New York Academy of Sciences, 2006
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

Petri Salven - One of the best experts on this subject based on the ideXlab platform.

  • Abnormal lymphatic‐like differentiation and Endothelial progenitor Cell activation in hemi retinal vein occlusion
    Acta Ophthalmologica, 2015
    Co-Authors: Sirpa Loukovaara, Petri Salven, Erika Gucciardo, Pauliina Repo, Jouko Lohi, Kaisa Lehti
    Abstract:

    Purpose Pathological vascular differentiation in retinal vein occlusion-related neovessel formation remains poorly characterized. The role of the intraocular lymphatic-like differentiation or Endothelial progenitor Cell activity has not been studied in this disease. Methods An eye with hemi retinal vein occlusion (RVO) underwent vitrectomy, neovessel membrane located at the optic nerve head was removed and subjected to immunohistochemistry. Characterization of the neovascular tissue was performed using hematoxylin and eosin, α-smooth muscle actin and pan-Endothelial Cell adhesion molecule (CD31). Expression of lymphatic Endothelial Cell (LEC) markers was studied by lymphatic vessel hyaluronan Endothelial receptor-(LYVE)-1, podoplanin (PDPN), and prospero homeobox protein (Prox)-1. Potential vascular Stem/progenitor Cells were identified by active Cellular proliferation (Ki67) and expression of the Stem Cell marker CD117. Results Specimen contained blood vessels lined by ECs and surrounded by pericytes. Immunoreactivity for LYVE-1 and Prox-1 was detected, with Prox-1 being more widely expressed in the vessels. PDPN expression was found in the extravascular structures representing potentially monocyte- or bone-marrow derived Cells. Expression of Stem Cell marker CD117 in actively proliferating Ki67-expressing ECs suggested for vascular Endothelial Stem Cell activity. Conclusions Intraocular lymphatic-like differentiation coupled with Endothelial Stem/progenitor Cell activation may be involved in the pathology of neovessel formation in ischemia-induced human hemi-RVO.

  • Generation of Functional Blood Vessels from a Single c-kit+ Adult Vascular Endothelial Stem Cell
    PLoS biology, 2012
    Co-Authors: Shentong Fang, Jing Wei, Nalle Pentinmikko, Hannele Leinonen, Petri Salven
    Abstract:

    In adults, the growth of blood vessels, a process known as angiogenesis, is essential for organ growth and repair. In many disorders including cancer, angiogenesis becomes excessive. The Cellular origin of new vascular Endothelial Cells (ECs) during blood vessel growth in angiogenic situations has remained unknown. Here, we provide evidence for adult vascular Endothelial Stem Cells (VESCs) that reside in the blood vessel wall endothelium. VESCs constitute a small subpopulation within CD117+ (c-kit+) ECs capable of undergoing clonal expansion while other ECs have a very limited proliferative capacity. Isolated VESCs can produce tens of millions of Endothelial daughter Cells in vitro. A single transplanted c-kit-expressing VESC by the phenotype lin−CD31+CD105+Sca1+CD117+ can generate in vivo functional blood vessels that connect to host circulation. VESCs also have long-term self-renewal capacity, a defining functional property of adult Stem Cells. To provide functional verification on the role of c-kit in VESCs, we show that a genetic deficit in Endothelial c-kit expression markedly decreases total colony-forming VESCs. In vivo, c-kit expression deficit resulted in impaired EC proliferation and angiogenesis and retardation of tumor growth. Isolated VESCs could be used in Cell-based therapies for cardiovascular repair to restore tissue vascularization after ischemic events. VESCs also provide a novel Cellular target to block pathological angiogenesis and cancer growth.

  • Stem Cells in tumor angiogenesis.
    Journal of molecular and cellular cardiology, 2010
    Co-Authors: Shentong Fang, Petri Salven
    Abstract:

    Contribution from diverse tissue-specific Stem Cell types is required to create the Cell populations necessary for the activation of angiogenesis and neovascular growth in cancer. Bone marrow (BM)-derived circulating Endothelial progenitors (EPCs) that would differentiate to bona fide Endothelial Cells (ECs) were previously believed to be necessary for tumor angiogenesis. However, numerous recent studies demonstrate that EPCs are not needed for tumor angiogenesis and indicate EPCs to be artifactual rather than physiological. It is evident that tumor infiltrating hematopoietic Cells produced by BM-residing hematopoietic Stem Cells (HSCs) may contribute to tumor angiogenesis in a paracrine manner by stimulating ECs or by remodeling the extraCellular matrix. Therefore, identification of the various hematopoietic Cell subpopulations that are critical for tumor angiogenesis and better understanding of their proangiogenic functions and mechanisms of action have potential therapeutic significance. Stem and progenitor Cell subsets for also other vascular or perivascular Cell types such as pericytes or mesenchymal/stromal Cells may provide critical contributions to the growing neovasculature. Furthermore, we hypothesize that the existence of a yet undiscovered-and largely unsearched-tissue-specific adult vascular Endothelial Stem Cell (VESC) would provide completely novel targeted approaches to block pathological angiogenesis and cancer growth. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".

Malcolm A S Moore - One of the best experts on this subject based on the ideXlab platform.

  • Mobilization of Endothelial and Hematopoietic Stem and Progenitor Cells by Adenovector‐Mediated Elevation of Serum Levels of SDF‐1, VEGF, and Angiopoietin‐1
    Annals of the New York Academy of Sciences, 2011
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

  • mobilization of Endothelial and hematopoietic Stem and progenitor Cells by adenovector mediated elevation of serum levels of sdf 1 vegf and angiopoietin 1
    Annals of the New York Academy of Sciences, 2006
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

Annelies Bronckaers - One of the best experts on this subject based on the ideXlab platform.

  • Chorioallantoic Membrane Assay as Model for Angiogenesis in Tissue Engineering: Focus on Stem Cells
    Tissue engineering. Part B Reviews, 2020
    Co-Authors: Greet Merckx, Hanna Tay, Melissa Lo Monaco, Marc A. M. J. Van Zandvoort, Ward De Spiegelaere, Ivo Lambrichts, Annelies Bronckaers
    Abstract:

    Tissue engineering aims to structurally and functionally regenerate damaged tissues, which requires the formation of new blood vessels that supply oxygen and nutrients by the process of angiogenesis. Stem Cells are a promising tool in regenerative medicine due to their combined differentiation and paracrine angiogenic capacities. The study of their proangiogenic properties and associated potential for tissue regeneration requires complex in vivo models comprising all steps of the angiogenic process. The highly vascularized extraembryonic chorioallantoic membrane (CAM) of fertilized chicken eggs offers a simple, easy accessible, and cheap angiogenic screening tool compared to other animal models. Although the CAM assay was initially primarily performed for evaluation of tumor growth and metastasis, Stem Cell studies using this model are increasing. In this review, a detailed summary of angiogenic observations of different mesenchymal, cardiac, and Endothelial Stem Cell types and derivatives in the CAM model is presented. Moreover, we focus on the variation in experimental setup, including the benefits and limitations of in ovo and ex ovo protocols, diverse biological and synthetic scaffolds, imaging techniques, and outcome measures of neovascularization. Finally, advantages and disadvantages of the CAM assay as a model for angiogenesis in tissue engineering in comparison with alternative in vivo animal models are described. Impact statement The chorioallantoic membrane (CAM) assay is an easy and cheap screening tool for the angiogenic properties of Stem Cells and their associated potential in the tissue engineering field. This review offers an overview of all published angiogenic studies of Stem Cells using this model, with emphasis on the variation in used experimental timeline, culture protocol (in ovo vs. ex ovo), Stem Cell type (derivatives), scaffolds, and outcome measures of vascularization. The purpose of this overview is to aid tissue engineering researchers to determine the ideal CAM experimental setup based on their specific study goals.

Jaehung Shieh - One of the best experts on this subject based on the ideXlab platform.

  • Mobilization of Endothelial and Hematopoietic Stem and Progenitor Cells by Adenovector‐Mediated Elevation of Serum Levels of SDF‐1, VEGF, and Angiopoietin‐1
    Annals of the New York Academy of Sciences, 2011
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

  • mobilization of Endothelial and hematopoietic Stem and progenitor Cells by adenovector mediated elevation of serum levels of sdf 1 vegf and angiopoietin 1
    Annals of the New York Academy of Sciences, 2006
    Co-Authors: Malcolm A S Moore, K Hattori, B Heissig, Jaehung Shieh, Sergio Dias, Ronald G Crystal, Shahin Rafii
    Abstract:

    : The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of Cell types that express the CXCR4 receptor. SDF-1-responsive Cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ Cells, including both hematopoietic progenitors and Stem Cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and Cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating Endothelial Stem Cell characterized by expression of the VEGFR2 (Flk-1/KDR). This Cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic Stem and progenitor Cells and a population of Flk-1-positive Endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of Endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.