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He JQ, January CT, Thomson JA, Kamp TJ. Human embryonic stem cell-derived cardiomyocytes: drug discovery and safety pharmacology. Expert Opin Drug Discov 2013; 2:739-53. [PMID: 23488962 DOI: 10.1517/17460441.2.5.739] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Human embryonic stem cells (hESCs) can provide potentially unlimited quantities of a wide range of human cell types that can be used in drug discovery and development, basic research and regenerative medicine. In this review, the authors describe the differentiation of hESCs into cardiomyocytes and outline the properties of hESC-derived cardiomyocytes (hESC-CMs), including their cardiac-type action potentials and contractile characteristics. In vitro cellular assays using hESC-CMs, which can be genetically engineered to create target-specific reporters as well as human disease models, will have applications at multiple stages of the drug discovery process. Furthermore, cardiac safety pharmacology assays evaluating the risk of proarrhythmic side effects associated with QT prolongation may be enhanced in their predictive value with the use of hESC-CMs.
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Affiliation(s)
- Jia-Qiang He
- Cellular Dynamics International, Inc., 525 Science Drive, Suite 200, Madison, WI 53711, USA +1 608 263 4856 ; +1 608 263 0405 ;
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2
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Martin LK, Bratoeva M, Mezentseva NV, Bernanke JM, Rémond MC, Ramsdell AF, Eisenberg CA, Eisenberg LM. Inhibition of heart formation by lithium is an indirect result of the disruption of tissue organization within the embryo. Dev Growth Differ 2012; 54:153-66. [PMID: 22150286 PMCID: PMC3288208 DOI: 10.1111/j.1440-169x.2011.01313.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Lithium is a commonly used drug for the treatment of bipolar disorder. At high doses, lithium becomes teratogenic, which is a property that has allowed this agent to serve as a useful tool for dissecting molecular pathways that regulate embryogenesis. This study was designed to examine the impact of lithium on heart formation in the developing frog for insights into the molecular regulation of cardiac specification. Embryos were exposed to lithium at the beginning of gastrulation, which produced severe malformations of the anterior end of the embryo. Although previous reports characterized this deformity as a posteriorized phenotype, histological analysis revealed that the defects were more comprehensive, with disfigurement and disorganization of all interior tissues along the anterior-posterior axis. Emerging tissues were poorly segregated and cavity formation was decreased within the embryo. Lithium exposure also completely ablated formation of the heart and prevented myocardial cell differentiation. Despite the complete absence of cardiac tissue in lithium treated embryos, exposure to lithium did not prevent myocardial differentiation of precardiac dorsal marginal zone explants. Moreover, precardiac tissue freed from the embryo subsequent to lithium treatment at gastrulation gave rise to cardiac tissue, as demonstrated by upregulation of cardiac gene expression, display of sarcomeric proteins, and formation of a contractile phenotype. Together these data indicate that lithium's effect on the developing heart was not due to direct regulation of cardiac differentiation, but an indirect consequence of disrupted tissue organization within the embryo.
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Affiliation(s)
- Lisa K. Martin
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Momka Bratoeva
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Nadejda V. Mezentseva
- New York Medical College/Westchester Medical Center Stem Cell Laboratory, Departments of Physiology and Medicine, New York Medical College. Valhalla, NY 10595, USA
| | - Jayne M. Bernanke
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Mathieu C. Rémond
- New York Medical College/Westchester Medical Center Stem Cell Laboratory, Departments of Physiology and Medicine, New York Medical College. Valhalla, NY 10595, USA
| | - Ann F. Ramsdell
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | - Carol A. Eisenberg
- New York Medical College/Westchester Medical Center Stem Cell Laboratory, Departments of Physiology and Medicine, New York Medical College. Valhalla, NY 10595, USA
| | - Leonard M. Eisenberg
- New York Medical College/Westchester Medical Center Stem Cell Laboratory, Departments of Physiology and Medicine, New York Medical College. Valhalla, NY 10595, USA
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3
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Abstract
Genetic studies of Wnt11 have revealed many insights into the roles and regulation of Wnt11, particularly during development. New tools to study Wnt11 have recently become available, making it timely to review the literature regarding this unique Wnt family member. In this study, we focus on mammalian Wnt11, describing its main sites of expression during development, and how the Wnt11 gene is regulated. We highlight an emerging theme in which canonical Wnt signals regulate Wnt11 expression through transcription factors in addition to, or other than, Tcf/LEF family members. We also discuss the frizzled family and other receptors that bind to Wnt11, the intracellular kinases and small GTPases that act downstream of Wnt11, and the effects of Wnt11 on Wnt/β-catenin signalling. Finally, we elaborate on the relevance of Wnt11 to human cancer, where it appears to be important both for proliferation and/or survival during normal differentiation and for migration/invasion.
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Affiliation(s)
- P Uysal-Onganer
- Department of Surgery and Cancer, Imperial College London, UK
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4
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Kasyanov VA, Hodde J, Hiles MC, Eisenberg C, Eisenberg L, De Castro LEF, Ozolanta I, Murovska M, Draughn RA, Prestwich GD, Markwald RR, Mironov V. Rapid biofabrication of tubular tissue constructs by centrifugal casting in a decellularized natural scaffold with laser-machined micropores. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:329-337. [PMID: 18807150 DOI: 10.1007/s10856-008-3590-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Accepted: 09/04/2008] [Indexed: 05/26/2023]
Abstract
Centrifugal casting allows rapid biofabrication of tubular tissue constructs by suspending living cells in an in situ cross-linkable hydrogel. We hypothesize that introduction of laser-machined micropores into a decellularized natural scaffold will facilitate cell seeding by centrifugal casting and increase hydrogel retention, without compromising the biomechanical properties of the scaffold. Micropores with diameters of 50, 100, and 200 mum were machined at different linear densities in decellularized small intestine submucosa (SIS) planar sheets and tubular SIS scaffolds using an argon laser. The ultimate stress and ultimate strain values for SIS sheets with laser-machined micropores with diameter 50 mum and distance between holes as low as 714 mum were not significantly different from unmachined control SIS specimens. Centrifugal casting of GFP-labeled cells suspended in an in situ cross-linkable hyaluronan-based hydrogel resulted in scaffold recellularization with a high density of viable cells inside the laser-machined micropores. Perfusion tests demonstrated the retention of the cells encapsulated within the HA hydrogel in the microholes. Thus, an SIS scaffold with appropriately sized microholes can be loaded with hydrogel encapsulated cells by centrifugal casting to give a mechanically robust construct that retains the cell-seeded hydrogel, permitting rapid biofabrication of tubular tissue construct in a "bioreactor-free" fashion.
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5
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Inai K, Norris RA, Hoffman S, Markwald RR, Sugi Y. BMP-2 induces cell migration and periostin expression during atrioventricular valvulogenesis. Dev Biol 2007; 315:383-96. [PMID: 18261719 DOI: 10.1016/j.ydbio.2007.12.028] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 12/19/2007] [Accepted: 12/20/2007] [Indexed: 11/26/2022]
Abstract
Atrioventricular (AV) endocardium transforms into the cushion mesenchyme, the primordia of the valves and membranous septa, through epithelial-mesenchymal transformation (EMT). While bone morphogenetic protein (BMP)-2 is known to be critical for AV EMT, the role of BMP-2 in post-EMT AV valvulogenesis remains to be elucidated. To find BMP signaling loops, we first localized Type I BMP receptors (BMPRs), BMPR-1A (ALK3), -1B (ALK6) and ALK2 in AV cushion mesenchyme in stage-24 chick embryos. Based on the BMP receptor expression pattern, we examined the functional roles of BMP-2 and BMP signaling in post-EMT valvulogenesis by using stage-24 AV cushion mesenchymal cell aggregates cultured on 3D-collagen gels. Exogenous BMP-2 or constitutively active (ca) BMPR-1B (ALK6)-virus treatments induced migration of the mesenchymal cells into the collagen gels, whereas noggin, an antagonist of BMPs, or dominant-negative (dn) BMPR-1 B (ALK6)-virus treatments reduced cell migration from the mesenchymal cell aggregates. Exogenous BMP-2 or caBMPR-1B (ALK6) treatments significantly promoted expression of an extracellular matrix (ECM) protein, periostin, a known valvulogenic matrix maturation mediator, at both mRNA and protein levels, whereas periostin expression was repressed by adding noggin or dnBMPR-1B (ALK6)-virus to the culture. Moreover, transcripts of Twist and Id1, which have been implicated in cell migration in embryogenesis and activation of the periostin promoter, were induced by BMP-2 but repressed by noggin in cushion mesenchymal cell cultures. These data provide evidence that BMP-2 and BMP signaling induce biological processes involved in early AV valvulogenesis, i.e. mesenchymal cell migration and expression of periostin, indicating critical roles for BMP signaling in post-EMT AV cushion tissue maturation and differentiation.
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Affiliation(s)
- Kei Inai
- Department of Cell Biology and Anatomy and Cardiovascular Developmental Biology Center, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425, USA
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6
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Abstract
In this review we discuss the major morphogenetic and regulative events that control myocardial progenitor cells from the time that they delaminate from the epiblast in the primitive streak to their differentiation into cardiomyocytes in the heart tube. During chick and mouse embryogenesis, myocardial progenitor cells go through four specific processes that are sequential but overlapping: specification of the cardiogenic mesoderm, determination of the bilaterally symmetric heart fields, patterning of the heart field, and finally cardiomyocyte differentiation and formation of the heart tube. We describe the morphological and molecular events that play a pivotal role in each of these four processes.
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Affiliation(s)
- Radwan Abu-Issa
- Department of Pediatrics, Neonatal-Perinatal Research Institute, Duke University, Durham, NC 27712, USA.
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7
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Abstract
Recent advances in organ printing technology for applications relating to medical interventions and organ replacement are described. Organ printing refers to the placement of various cell types into a soft scaffold fabricated according to a computer-aided design template using a single device. Computer aided scaffold topology design has recently gained attention as a viable option to achieve function and mass transport requirements within tissue engineering scaffolds. An exciting advance pioneered in our laboratory is that of simultaneous printing of cells and biomaterials, which allows precise placement of cells and proteins within 3-D hydrogel structures. This advance raises the possibility of spatially controlling not only the scaffold structure, but also the type of tissue that can be grown within the scaffold and the thickness of the tissue as capillaries and vessels could be constructed within the scaffolds. Here we summarize recent advances in printing cells and materials using the same device.
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Affiliation(s)
- Thomas Boland
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA.
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8
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Pérez-Pomares JM, Mironov V, Guadix JA, Macías D, Markwald RR, Muñoz-Chápuli R. In vitro self-assembly of proepicardial cell aggregates: An embryonic vasculogenic model for vascular tissue engineering. ACTA ACUST UNITED AC 2006; 288:700-13. [PMID: 16761281 DOI: 10.1002/ar.a.20338] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Proepicardial/epicardial-derived cells are the main origin of the early embryonic coronary vascular bed. In vivo coronary vasculogenesis, which is a fast-occurring event, can be mimicked in vitro by culturing proepicardial tissue in different ways. The in vitro vasculogenic model presented in this study (a proepicardial suspension culture assay) partially reproduces coronary vascular development from its cellular precursors, a process known to be highly dependent on cell migration, cell differentiation, cell adhesion/sorting, and tissue fusion phenomena. The main aim of this study is to study the triggering signals and the cellular dynamics that regulate the differentiation of proepicardial cells into the angioblastic/endothelial lineage and their in vitro vasculogenic potential. Our results indicate that hanging drop-cultured proepicardia, which have an intrinsic vascular potential, behave like self-assembling cell aggregates or spheroids that can fuse to give rise to complex vascularized 3D structures. We believe that these self-assembling cell aggregates are an optimal choice to study the differentiation of coronary angioblasts, as well as a good method to reproduce vascular development in vitro. Finally, we propose the proepicardium as a suitable cellular source for vascular tissue engineering.
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Affiliation(s)
- José M Pérez-Pomares
- Department of Animal Biology, Faculty of Science, University of Málaga, Málaga, Spain.
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9
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Mironov V, Kasyanov V, Zheng Shu X, Eisenberg C, Eisenberg L, Gonda S, Trusk T, Markwald RR, Prestwich GD. Fabrication of tubular tissue constructs by centrifugal casting of cells suspended in an in situ crosslinkable hyaluronan-gelatin hydrogel. Biomaterials 2005; 26:7628-35. [PMID: 16023201 DOI: 10.1016/j.biomaterials.2005.05.061] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Accepted: 05/16/2005] [Indexed: 10/25/2022]
Abstract
Achieving the optimal cell density and desired cell distribution in scaffolds is a major goal of cell seeding technologies in tissue engineering. In order to reach this goal, a novel centrifugal casting technology was developed using in situ crosslinkable hyaluronan-based (HA) synthetic extracellular matrix (sECM). Living cells were suspended in a viscous solution of thiol-modified HA and thiol-modified gelatin, a polyethyleneglycol diacrylate crosslinker was added, and a hydrogel was formed during rotation. The tubular tissue constructs consisting of a densely packed cell layer were fabricated with the rotation device operating at 2000 rpm for 10 min. The majority of cells suspended in the HA mixture before rotation were located inside the layer after centrifugal casting. Cells survived the effect of the centrifugal forces experienced under the rotational regime employed. The volume cell density (65.6%) approached the maximal possible volume density based on theoretical sphere packing models. Thus, centrifugal casting allows the fabrication of tubular constructs with the desired redistribution, composition and thickness of cell layers that makes the maximum efficient use of available cells. Centrifugal casting in this sECM would enable rapid fabrication of tissue-engineered vascular grafts, as well as other tubular and planar tissue-engineered constructs.
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Affiliation(s)
- Vladimir Mironov
- Medical University of South Carolina, Charleston, SC 29426, USA.
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10
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Eisenberg LM, Moreno R, Markwald RR. Multiple stem cell populations contribute to the formation of the myocardium. Ann N Y Acad Sci 2005; 1047:38-49. [PMID: 16093483 DOI: 10.1196/annals.1341.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Owing to the very rapid growth of the vertebrate embryo following fertilization, an efficient circulatory system needs to be established during the initial stages of development. For that reason, the first functional organ that develops in both the bird and mammalian embryo is the heart. Until recently, the narrative of cardiac development was portrayed in a straightforward manner, with all the myocardium in the mature heart being generated from the expansion of an original pool of myocardial cells present in the early gastrula. It is now known that the story of the developing myocardium is more dynamic, as it is comprises cellular components of multiple ancestries. The de novo addition of myocytes to the developing heart occurs at various points during embryogenesis, as cardiac muscle takes on new members by the absorption of cells that either reside in neighboring nonmuscle tissue or come into contact with the myocardium by entering the heart upon migration or via the circulation. This article reviews what is presently known about cellular populations that contribute to the myocardium and examine reasons why the embryo utilizes multiple cellular sources for forming the cardiac muscle.
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Affiliation(s)
- Leonard M Eisenberg
- Medical University of South Carolina, Department of Cell Biology and Anatomy, BSB Rm. 642, 171 Ashley Avenue, Charleston, SC 29425, USA
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11
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Muñoz-Chápuli R, Carmona R, Guadix JA, Macías D, Pérez-Pomares JM. The origin of the endothelial cells: an evo-devo approach for the invertebrate/vertebrate transition of the circulatory system. Evol Dev 2005; 7:351-8. [PMID: 15982372 DOI: 10.1111/j.1525-142x.2005.05040.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Circulatory systems of vertebrate and invertebrate metazoans are very different. Large vessels of invertebrates are constituted of spaces and lacunae located between the basement membranes of endodermal and mesodermal epithelia, and they lack an endothelial lining. Myoepithelial differentation of the coelomic cells covering hemal spaces is a frequent event, and myoepithelial cells often form microvessels in some large invertebrates. There is no phylogenetic theory about the origin of the endothelial cells in vertebrates. We herein propose that endothelial cells originated from a type of specialized blood cells, called amoebocytes, that adhere to the vascular basement membrane. The transition between amoebocytes and endothelium involved the acquisition of an epithelial phenotype. We suggest that immunological cooperation was the earliest function of these protoendothelial cells. Furthermore, their ability to transiently recover the migratory, invasive phenotype of amoebocytes (i.e., the angiogenic phenotype) allowed for vascular growth from the original visceral areas to the well-developed somatic areas of vertebrates (especially the tail, head, and neural tube). We also hypothesize that pericytes and smooth muscle cells derived from myoepithelial cells detached from the coelomic lining. As the origin of blood cells in invertebrates is probably coelomic, our hypothesis relates the origin of all the elements of the circulatory system with the coelomic wall. We have collected from the literature a number of comparative and developmental data supporting our hypothesis, for example the localization of the vascular endothelial growth factor receptor-2 ortholog in hemocytes of Drosophila or the fact that circulating progenitors can differentiate into endothelial cells even in adult vertebrates.
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Affiliation(s)
- R Muñoz-Chápuli
- Department of Animal Biology, Faculty of Science, University of Málaga, E-29071 Málaga, Spain.
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12
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Eisenberg LM, Markwald RR. Cellular recruitment and the development of the myocardium. Dev Biol 2004; 274:225-32. [PMID: 15385154 DOI: 10.1016/j.ydbio.2004.07.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Revised: 07/01/2004] [Accepted: 07/23/2004] [Indexed: 10/26/2022]
Abstract
The vertebrate embryo experiences very rapid growth following fertilization. This necessitates the establishment of blood circulation, which is initiated during the early somite stages of development when the embryo begins to exhibit three-dimensional tissue organization. Accordingly, the contractile heart is the first functional organ that develops in both the bird and mammalian embryo. The vertebrate heart is quickly assembled as a simple two-layer tube consisting of an outer myocardium and inner endocardium. During embryogenesis, the heart undergoes substantial growth and remodeling to meet the increased circulatory requirements of an adult organism. Until recently, it was thought that all the cells that comprise the muscle of the mature heart could trace their roots back to two bilaterally distributed mesodermal fields within the early gastrula. It is now known that the cellular components that give rise to the myocardium have multiple ancestries and that de novo addition of cardiac myocytes to the developing heart occurs at various points during embryogenesis. In this article, we review what is presently known about the source of the cells that contribute to the myocardium and explore reasons why multiple myocardial cell sources exist.
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Affiliation(s)
- Leonard M Eisenberg
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, SC 29425, USA.
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13
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Abstract
Development of a multicellular organism is accomplished through a series of events that are preprogrammed in the genome. These events encompass cellular proliferation, lineage commitment, lineage progression, lineage expression, cellular inhibition, and regulated apoptosis. The sequential progression of cells through these events results in the formation of the differentiated cells, tissues, and organs that constitute an individual. Although most cells progress through this sequence during development, a few cells leave the developmental continuum to become reserve precursor cells. The reserve precursor cells are involved in the continual maintenance and repair of the tissues and organs throughout the life span of the individual. Until recently it was generally assumed that the precursor cells in postnatal individuals were limited to lineage-committed progenitor cells specific for various tissues. However, studies by Young, his colleagues, and others have demonstrated the presence of two categories of precursor cells that reside within the organs and tissues of postnatal animals. These two categories of precursor cells are lineage-committed (multipotent, tripotent, bipotent, and unipotent) progenitor cells and lineage-uncommitted pluripotent (epiblastic-like, ectodermal, mesodermal, and endodermal) stem cells. These reserve precursor cells provide for the continual maintenance and repair of the organism after birth.
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Affiliation(s)
- Henry E Young
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia 31207, USA.
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14
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Eisenberg LM, Kubalak SW, Eisenberg CA. Stem cells and the formation of the myocardium in the vertebrate embryo. THE ANATOMICAL RECORD. PART A, DISCOVERIES IN MOLECULAR, CELLULAR, AND EVOLUTIONARY BIOLOGY 2004; 276:2-12. [PMID: 14699629 PMCID: PMC3096003 DOI: 10.1002/ar.a.10130] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A major goal in cardiovascular biology is to repair diseased or damaged hearts with newly generated myocardial tissue. Stem cells offer a potential source of replacement myocytes for restoring cardiac function. Yet little is known about the nature of the cells that are able to generate myocardium and the conditions they require to form heart tissue. A source of information that may be pertinent to addressing these issues is the study of how the myocardium arises from progenitor cells in the early vertebrate embryo. Accordingly, this review will examine the initial events of cardiac developmental biology for insights into the identity and characteristics of the stem cells that can be used to generate myocardial tissue for therapeutic purposes.
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Affiliation(s)
- Leonard M Eisenberg
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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15
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Young HE, Duplaa C, Yost MJ, Henson NL, Floyd JA, Detmer K, Thompson AJ, Powell SW, Gamblin TC, Kizziah K, Holland BJ, Boev A, Van De Water JM, Godbee DC, Jackson S, Rimando M, Edwards CR, Wu E, Cawley C, Edwards PD, Macgregor A, Bozof R, Thompson TM, Petro GJ, Shelton HM, McCampbell BL, Mills JC, Flynt FL, Steele TA, Kearney M, Kirincich-Greathead A, Hardy W, Young PR, Amin AV, Williams RS, Horton MM, McGuinn S, Hawkins KC, Ericson K, Terracio L, Moreau C, Hixson D, Tobin BW, Hudson J, Bowyer FP, Black AC. Clonogenic analysis reveals reserve stem cells in postnatal mammals. II. Pluripotent epiblastic-like stem cells. ACTA ACUST UNITED AC 2004; 277:178-203. [PMID: 14983513 DOI: 10.1002/ar.a.20000] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Undifferentiated cells have been identified in the prenatal blastocyst, inner cell mass, and gonadal ridges of rodents and primates, including humans. After isolation these cells express molecular and immunological markers for embryonic cells, capabilities for extended self-renewal, and telomerase activity. When allowed to differentiate, embryonic stem cells express phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. When implanted in vivo, undifferentiated noninduced embryonic stem cells formed teratomas. In this report we describe a cell clone isolated from postnatal rat skeletal muscle and derived by repetitive single-cell clonogenic analysis. In the undifferentiated state it consists of very small cells having a high ratio of nucleus to cytoplasm. The clone expresses molecular and immunological markers for embryonic stem cells. It exhibits telomerase activity, which is consistent with its extended capability for self-renewal. When induced to differentiate, it expressed phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. The clone was designated as a postnatal pluripotent epiblastic-like stem cell (PPELSC). The undifferentiated clone was transfected with a genomic marker and assayed for alterations in stem cell characteristics. No alterations were noted. The labeled clone, when implanted into heart after injury, incorporated into myocardial tissues undergoing repair. The labeled clone was subjected to directed lineage induction in vitro, resulting in the formation of islet-like structures (ILSs) that secreted insulin in response to a glucose challenge. This study suggests that embryonic-like stem cells are retained within postnatal mammals and have the potential for use in gene therapy and tissue engineering.
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Affiliation(s)
- Henry E Young
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia 31207, USA.
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16
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Eisenberg LM, Burns L, Eisenberg CA. Hematopoietic cells from bone marrow have the potential to differentiate into cardiomyocytes in vitro. THE ANATOMICAL RECORD. PART A, DISCOVERIES IN MOLECULAR, CELLULAR, AND EVOLUTIONARY BIOLOGY 2003; 274:870-82. [PMID: 12923898 DOI: 10.1002/ar.a.10106] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Recent studies have indicated that hematopoietic progenitor cells (HPCs) have the capacity to form cardiomyocytes. In the present study, we further examined the cardiac competence of HPCs by asking whether these cells by themselves can be provoked to undergo cardiac differentiation. Our data indicate that in response to growth factor treatment, HPCs from avian bone marrow (BM) can undergo cardiac differentiation, as indicated by their expression of multiple cardiac transcription factors and sarcomeric proteins. Furthermore, coculture experiments with adult mouse BM cells and embryonic heart tissue confirmed that HPCs are able to both integrate into cardiac tissue and differentiate into cardiomyocytes. In an additional set of experiments, we investigated whether other hematopoietic populations might possess cardiac potential by examining whether blood cells that normally are recruited to damaged tissue might act as a source of newly generated cardiomyocytes. Remarkably, macrophages cocultured with cardiac explants also demonstrated an ability to integrate into contractile heart tissue and undergo cardiac differentiation. Thus, our data suggest that the capacity of blood cells to transdifferentiate into cardiomyocytes is not limited to classically defined hematopoietic progenitors.
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Affiliation(s)
- Leonard M Eisenberg
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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17
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Linask KK. Regulation of heart morphology: current molecular and cellular perspectives on the coordinated emergence of cardiac form and function. BIRTH DEFECTS RESEARCH. PART C, EMBRYO TODAY : REVIEWS 2003; 69:14-24. [PMID: 12768654 DOI: 10.1002/bdrc.10004] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND During early heart development, in addition to cells being induced to differentiate into cardiomyocytes, pathways are activated that lead to cardiac morphogenesis or the development of form. METHODS Orchestration of organogenesis involves the incremental activation of regulatory pathways that lead to pivotal transition points, such as cardiac compartment delineation and looping. Each embryonic stage sets up the correct patterning of morphoregulatory molecules that will regulate the next process, until an organ is formed from the mesoderm layer after gastrulation. The current review provides an understanding of the morphoregulatory, cell adhesion and extracellular matrix-mediated, processes that coordinate development of heart form with that of function. The period reviewed encompasses the formation of a definitive cardiac compartment from the lateral plate mesoderm to the time-point in which the single, beating heart tube loops directionally to the right. Looping results in the correct spatial orientation for subsequent modeling of the four-chambered heart. Even subtle alterations in looping can form the basis upon which malformations of the inlet or the outlet regions of the heart, or both, are superimposed. RESULTS In the future, DNA microarray data sets may allow modeling the specific sequence of gene regulatory dynamics leading to these transition points to discover the regulatory "modes" that the cells adopt during heart organogenesis. The regulatory genes, however, can only specify the proteins that will be present. CONCLUSIONS To fully understand the timing and mechanisms underlying heart development, it is necessary to define the sequential synthesis, patterning, and interaction of the proteins, and of still other receptors, which eventually drive cells to organize into functioning organs.
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Affiliation(s)
- Kersti K Linask
- Department of Cell Biology, University of Medicine and Dentistry of New Jersey-SOM Stratford, NJ 08084, USA.
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18
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Abstract
Development of the heart is a complex process involving primary and secondary heart fields that are set aside to generate myocardial and endocardial cell lineages. The molecular inductions that occur in the primary heart field appear to be recapitulated in induction and myocardial differentiation of the secondary heart field, which adds the conotruncal segments to the primary heart tube. While much is now known about the initial steps and factors involved in induction of myocardial differentiation, little is known about induction of endocardial development. Many of the genes expressed by nascent myocardial cells, which then become committed to a specific heart segment, have been identified and studied. In addition to the heart fields, several other "extracardiac" cell populations contribute to the fully functional mature heart. Less is known about the genetic programs of extracardiac cells as they enter the heart and take part in cardiogenesis. The molecular/genetic basis of many congenital cardiac defects has been elucidated in recent years as a result of new insights into the molecular control of developmental events.
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Affiliation(s)
- Margaret L Kirby
- Department of Pediatrics, Division of Neonatology, Duke University Medical Center, Box 3179, Durham, NC 27710, USA.
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19
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Toma C, Pittenger MF, Cahill KS, Byrne BJ, Kessler PD. Human mesenchymal stem cells differentiate to a cardiomyocyte phenotype in the adult murine heart. Circulation 2002; 105:93-8. [PMID: 11772882 DOI: 10.1161/hc0102.101442] [Citation(s) in RCA: 1529] [Impact Index Per Article: 69.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Cellular cardiomyoplasty has been proposed as an alternative strategy for augmenting the function of diseased myocardium. We investigated the potential of human mesenchymal stem cells (hMSCs) from adult bone marrow to undergo myogenic differentiation once transplanted into the adult murine myocardium. METHODS AND RESULTS A small bone marrow aspirate was taken from the iliac crest of healthy human volunteers, and hMSCs were isolated as previously described. The stem cells, labeled with lacZ, were injected into the left ventricle of CB17 SCID/beige adult mice. At 4 days after injection, none of the engrafted hMSCs expressed myogenic markers. A limited number of cells survived past 1 week and over time morphologically resembled the surrounding host cardiomyocytes. Immunohistochemistry revealed de novo expression of desmin, beta-myosin heavy chain, alpha-actinin, cardiac troponin T, and phospholamban at levels comparable to those of the host cardiomyocytes; sarcomeric organization of the contractile proteins was observed. In comparison, neither cardiac troponin T nor phospholamban was detected in the myotubes formed in vitro by MyoD-transduced hMSCs. CONCLUSIONS The purified hMSCs from adult bone marrow engrafted in the myocardium appeared to differentiate into cardiomyocytes. The persistence of the engrafted hMSCs and their in situ differentiation in the heart may represent the basis for using these adult stem cells for cellular cardiomyoplasty.
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Affiliation(s)
- Catalin Toma
- Department of Medicine, Division of Cardiology, Johns Hopkins School of Medicine, Baltimore, Md, USA
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20
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Mjaatvedt CH, Nakaoka T, Moreno-Rodriguez R, Norris RA, Kern MJ, Eisenberg CA, Turner D, Markwald RR. The outflow tract of the heart is recruited from a novel heart-forming field. Dev Biol 2001; 238:97-109. [PMID: 11783996 DOI: 10.1006/dbio.2001.0409] [Citation(s) in RCA: 392] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
As classically described, the precardiac mesoderm of the paired heart-forming fields migrate and fuse anteriomedially in the ventral midline to form the first segment of the straight heart tube. This segment ultimately forms the right trabeculated ventricle. Additional segments are added to the caudal end of the first in a sequential fashion from the posteriolateral heart-forming field mesoderm. In this study we report that the final major heart segment, which forms the cardiac outflow tract, does not follow this pattern of embryonic development. The cardiac outlet, consisting of the conus and truncus, does not derive from the paired heart-forming fields, but originates separately from a previously unrecognized source of mesoderm located anterior to the initial primitive heart tube segment. Fate-mapping results show that cells labeled in the mesoderm surrounding the aortic sac and anterior to the primitive right ventricle are incorporated into both the conus and the truncus. Conversely, if cells are labeled in the existing right ventricle no incorporation into the cardiac outlet is observed. Tissue explants microdissected from this anterior mesoderm region are capable of forming beating cardiac muscle in vitro when cocultured with explants of the primitive right ventricle. These findings establish the presence of another heart-forming field. This anterior heart-forming field (AHF) consists of mesoderm surrounding the aortic sac immediately anterior to the existing heart tube. This new concept of the heart outlet's embryonic origin provides a new basis for explaining a variety of gene-expression patterns and cardiac defects described in both transgenic animals and human congenital heart disease.
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Affiliation(s)
- C H Mjaatvedt
- Department of Cell Biology and Anatomy, Medical University of South Carolina, 171 Ashley Avenue, Charleston, South Carolina 29425, USA.
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21
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Young HE, Steele TA, Bray RA, Hudson J, Floyd JA, Hawkins K, Thomas K, Austin T, Edwards C, Cuzzourt J, Duenzl M, Lucas PA, Black AC. Human reserve pluripotent mesenchymal stem cells are present in the connective tissues of skeletal muscle and dermis derived from fetal, adult, and geriatric donors. THE ANATOMICAL RECORD 2001; 264:51-62. [PMID: 11505371 DOI: 10.1002/ar.1128] [Citation(s) in RCA: 334] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This study details the profile of 13 cell surface cluster differentiation markers on human reserve stem cells derived from connective tissues. Stem cells were isolated from the connective tissues of dermis and skeletal muscle derived from fetal, mature, and geriatric humans. An insulin/dexamethasone phenotypic bioassay was used to determine the identity of the stem cells from each population. All populations contained lineage-committed myogenic, adipogenic, chondrogenic, and osteogenic progenitor stem cells as well as lineage-uncommitted pluripotent stem cells capable of forming muscle, adipocytes, cartilage, bone, fibroblasts, and endothelial cells. Flow cytometric analysis of adult stem cell populations revealed positive staining for CD34 and CD90 and negative staining for CD3, CD4, CD8, CD11c, CD33, CD36, CD38, CD45, CD117, Glycophorin-A, and HLA DR-II.
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Affiliation(s)
- H E Young
- Division of Basic Medical Science, Mercer University School of Medicine, Macon, Georgia 31207, USA.
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22
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Young HE, Duplaa C, Young TM, Floyd JA, Reeves ML, Davis KH, Mancini GJ, Eaton ME, Hill JD, Thomas K, Austin T, Edwards C, Cuzzourt J, Parikh A, Groom J, Hudson J, Black AC. Clonogenic analysis reveals reserve stem cells in postnatal mammals: I. Pluripotent mesenchymal stem cells. THE ANATOMICAL RECORD 2001; 263:350-60. [PMID: 11500811 DOI: 10.1002/ar.1112] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Clonal populations of lineage-uncommitted pluripotent mesenchymal stem cells have been identified in prenatal avians and rodents. These cells reside in the connective tissue matrices of many organs and tissues. They demonstrate extended capabilities for self-renewal and the ability to differentiate into multiple separate tissues within the mesodermal germ line. This study was designed to determine whether such cells are present in the connective tissues of postnatal mammals. This report describes a cell clone derived by isolation from postnatal rat connective tissues, cryopreservation, extended propagation, and serial dilution clonogenic analysis. In the undifferentiated state, this clone demonstrates a high nuclear-to-cytoplasmic ratio and extended capacity for self-renewal. Subsequent morphological, histochemical, and immunochemical analysis after the induction of differentiation revealed phenotypic markers characteristic of multiple cell types of mesodermal origin, such as skeletal muscle, smooth muscle, fat cells, cartilage, and bone. These results indicate that this clone consists of pluripotent mesenchymal stem cells. This report demonstrates that clonal populations of reserve stem cells are present in mammals after birth. Potential roles for such cells in the maintenance, repair, and regeneration of mesodermal tissues are discussed.
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Affiliation(s)
- H E Young
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia 31207, USA.
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23
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Young HE, Steele TA, Bray RA, Hudson J, Floyd JA, Hawkins K, Thomas K, Austin T, Edwards C, Cuzzourt J, Duenzl M, Lucas PA, Black AC. Human reserve pluripotent mesenchymal stem cells are present in the connective tissues of skeletal muscle and dermis derived from fetal, adult, and geriatric donors. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/ar.1128 [pii]] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
WNT proteins compose a family of secreted signaling molecules that regulate cell fate and behavior. The possible influence of WNTs on hematopoietic cell fate was examined. Both hematopoietic progenitor cell (HPC)–enriched embryonic avian bone marrow cells and the quail mesodermal stem cell line QCE6 were used for these studies. Under optimized conditions, the bone marrow and QCE6 cells behaved identically and developed into red blood cells (RBCs), monocytes, macrophages, granulocytes, and thrombocytes. This broad range of blood cell phenotypes exhibited by QCE6 cells was dependent on their active expression of WNT11. However, when QCE6 cells were prevented from producing WNT11—by expression of a stably transfected WNT11 antisense transgene—the cultures were dominated by highly vacuolated macrophages. RBCs were absent from these cultures, and the presence of monocytes was greatly diminished. Exposure of these WNT11 antisense cells to soluble WNT11 or WNT5a restored the broad range of blood cell phenotypes exhibited by parental QCE6 cells. Overexpression of WNT protein in QCE6 cells further increased the prevalence of RBCs and monocytes and greatly diminished the appearance of macrophages. Accordingly, treatment of HPC-enriched bone marrow cultures with soluble WNT11 or WNT5a inhibited macrophage formation. Instead, monocytes and RBCs were the prevalent cells displayed by WNT-treated bone marrow cultures. Together, these data indicate that WNTs may play a major role in regulating hematopoietic cell fate.
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25
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Abstract
Abstract
WNT proteins compose a family of secreted signaling molecules that regulate cell fate and behavior. The possible influence of WNTs on hematopoietic cell fate was examined. Both hematopoietic progenitor cell (HPC)–enriched embryonic avian bone marrow cells and the quail mesodermal stem cell line QCE6 were used for these studies. Under optimized conditions, the bone marrow and QCE6 cells behaved identically and developed into red blood cells (RBCs), monocytes, macrophages, granulocytes, and thrombocytes. This broad range of blood cell phenotypes exhibited by QCE6 cells was dependent on their active expression of WNT11. However, when QCE6 cells were prevented from producing WNT11—by expression of a stably transfected WNT11 antisense transgene—the cultures were dominated by highly vacuolated macrophages. RBCs were absent from these cultures, and the presence of monocytes was greatly diminished. Exposure of these WNT11 antisense cells to soluble WNT11 or WNT5a restored the broad range of blood cell phenotypes exhibited by parental QCE6 cells. Overexpression of WNT protein in QCE6 cells further increased the prevalence of RBCs and monocytes and greatly diminished the appearance of macrophages. Accordingly, treatment of HPC-enriched bone marrow cultures with soluble WNT11 or WNT5a inhibited macrophage formation. Instead, monocytes and RBCs were the prevalent cells displayed by WNT-treated bone marrow cultures. Together, these data indicate that WNTs may play a major role in regulating hematopoietic cell fate.
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26
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Abstract
To review the data on the origins, phenotype, and function of embryonic phagocytes that has accumulated over past decade. Most of the relevant articles were selected based on the PubMed database entries. In additional, the Interactive Fly database (http://sdb.bio. purdue.edu/fly/aimain/1aahome.htm), FlyBase (http://flybase.bio. indiana.edu:82/), and TBase (http://tbase.jax.org/) were used to search for relevant information and articles. Phagocytes in a vertebrate embryo develop in two sites (yolk sac and liver) and contribute to organogenesis in part through their ability to recognize and clear apoptotic cells. Yolk sac-derived phagocytes differ in differentiation pathway and marker gene expression from macrophages produced via classic hematopoietic progenitors in the liver. We argue that yolk sac-derived phagocytes constitute a separate cell lineage. This conclusion raises the question of whether primitive phagocytes persist into the adulthood.
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Affiliation(s)
- A M Lichanska
- Departments of Medical Genetics and Ophthalmology, Queen's University of Belfast, Belfast, United Kingdom
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27
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Mills KR, Kruep D, Saha MS. Elucidating the origins of the vascular system: a fate map of the vascular endothelial and red blood cell lineages in Xenopus laevis. Dev Biol 1999; 209:352-68. [PMID: 10328926 DOI: 10.1006/dbio.1999.9245] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Required to supply nutrients and oxygen to the growing embryo, the vascular system is the first functional organ system to develop during vertebrate embryogenesis. Although there has been substantial progress in identifying the genetic cascade regulating vascular development, the initial stages of vasculogenesis, namely, the origin of vascular endothelial cells within the early embryo, remain unclear. To address this issue we constructed a fate map for specific vascular structures, including the aortic arches, endocardium, dorsal aorta, cardinal veins, and lateral abdominal veins, as well as for the red blood cells at the 16-cell stage and the 32-cell stage of Xenopus laevis. Using genetic markers to identify these cell types, our results suggest that vascular endothelial cells can arise from virtually every blastomere of the 16-cell-stage and the 32-cell-stage embryo, with different blastomeres preferentially, though not exclusively, giving rise to specific vascular structures. Similarly, but more surprisingly, every blastomere in the 16-cell-stage embryo and all but those in the most animal tier of the 32-cell-stage embryo serve as progenitors for red blood cells. Taken together, our results suggest that during normal development, both dorsal and ventral blastomeres contribute significantly to the vascular endothelial and red blood cell lineages.
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Affiliation(s)
- K R Mills
- Department of Biology, College of William and Mary, Williamsburg, Virginia, 23187, USA
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28
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Kessler PD, Byrne BJ. Myoblast cell grafting into heart muscle: cellular biology and potential applications. Annu Rev Physiol 1999; 61:219-42. [PMID: 10099688 DOI: 10.1146/annurev.physiol.61.1.219] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review surveys a wide range of cellular and molecular approaches to strengthening the injured or weakened heart, focusing on strategies to replace dysfunctional, necrotic, or apoptotic cardiomyocytes with new cells of mesodermal origin. A variety of cell types, including myogenic cell lines, adult skeletal myoblasts, immoratalized atrial cells, embryonic and adult cardiomyocytes, embryonic stem cells, tetratoma cells, genetically altered fibroblasts, smooth muscle cells, and bone marrow-derived cells have all been proposed as useful cells in cardiac repair and may have the capacity to perform cardiac work. We focus on the implantation of mesodermally derived cells, the best developed of the options. We review the developmental and cell biology that have stimulated these studies, examine the limitations of current knowledge, and identify challenges for the future, which we believe are considerable.
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Affiliation(s)
- P D Kessler
- Peter Belfer Cardiac Laboratory, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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Yamada K, Kamihira M, Iijima S. Enhanced cell aggregation and liver functions using polymers modified with a cell-specific ligand in primary hepatocyte cultures. J Biosci Bioeng 1999; 88:557-62. [PMID: 16232661 DOI: 10.1016/s1389-1723(00)87675-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/1999] [Accepted: 08/18/1999] [Indexed: 11/16/2022]
Abstract
Hepatocytes cultured as multicellular aggregates called spheroids exhibit enhanced liver functions and maintain them over a long period compared with monolayer culture. We previously reported the induction of hepatocyte spheroids using the synthetic polymer Eudragit (a copolymer of methacrylic acid and methylmethacrylate) as an artificial matrix in a cell suspension system (Yamada et al., J. Biochem., 123, 1017-1023, 1998). In this method, hepatocyte aggregation was promoted by the effects of electrostatic and hydrophobic interactions between cells and the polymer. To enhance the cell aggregation ability and cell-specificity of the polymer, in the present study, we prepared hepatocyte-targeting polymers containing lactone, a ligand of the asialoglycoprotein receptor. Addition of the lactone-modified polymers to the medium promoted cell aggregation and spheroid formation more effectively than unmodified Eudragit. The spheroids induced by the polymers exhibited enhanced liver functions, i.e., albumin secretion, ammonia removal, and urea synthesis, from early in the culture. We also investigated the induction of hetero-spheroids composed of various liver constitutive cells by this method. The hetero-spheroids induced by the polymers showed improved liver functions.
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Affiliation(s)
- K Yamada
- Department of Biotechnology, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
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