STATE-OF-THE-ART PAPER
Transplantation of cells for cardiac repair
Rutger J. Hassink, MD*
,*,
Aart Brutel de la Rivière, MD, PhD*,
Christine L. Mummery, PhD
and
Pieter A. Doevendans, MD, PhD
* University Medical Center, Heart Lung Center, Department of Cardio-Thoracic Surgery, Utrecht, The Netherlands
Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands
Interuniversity Cardiology Institute of the Netherlands, Utrecht, The Netherlands
Manuscript received June 27, 2002;
revised manuscript received October 14, 2002,
accepted November 1, 2002.
* Reprint requests and correspondence: Dr. Rutger J. Hassink, University Medical Center Utrecht, Department of Cardio-Thoracic Surgery and Hubrecht Laboratory, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
rutger{at}niob.knaw.nl
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Abstract
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The inability of adult cardiomyocytes to divide to a significant extent and regenerate the myocardium after injury leads to permanent deficits in the number of functional cells, which can contribute to the development and progression of heart failure. The transplantation of skeletal myoblasts or stem cells or cardiomyocytes derived from them into the injured myocardium is a novel and promising approach in the treatment of cardiac disease and the restoration of myocardial function. In this article, skeletal myoblasts and embryonic and bone marrow stem cells are discussed in the context of their potential therapeutic use in cardiac failure. The state of the art in both laboratory and clinic is presented. We discuss current and intrinsic limitations of cardiac cellular transplantation and suggest directions for future research.
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Abbreviations and Acronyms
| | ES | | embryonic stem | | HF | | heart failure | | MI | | myocardial infarction | | NYHA | | New York Heart Association |
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Chronic heart diseases, such as ischemic and hypertensive heart pathologies, are characterized by irreversible loss of cardiomyocytes. Although terminally differentiated cardiomyocytes have been described as showing some evidence of mitotic division in the heart (1), the generally accepted concept in contemporary cardiology is that adult cardiomyocytes lack the ability to regenerate the myocardium, because they proliferate only up to the time of birth (2). This leads to permanent deficits in the number of viable cardiomyocytes and causes the development and progression of heart failure (HF).
Angiotensin-converting enzyme inhibitors and beta-adrenergic blockers have improved patient survival but are not a substitute for living, beating cells. Additionally, the development of non-pharmacological therapies, which may range from mechanical assistance devices to artificial hearts, holds great promise. Nevertheless, mortality remains high, and long-term outlooks for patients are still uncertain. Moreover, the contribution of heart transplantation to reducing mortality is limited because of a shortage of donor organs, the complications of immunosuppression, and the functional failure of the transplanted organs.
Cell transplantation for treating cardiac disease represents a tremendous opportunity for developing new therapeutic strategies. In this review, transplantation of skeletal myoblasts and embryonic and bone marrow stem cells is discussed in the light of its potential contribution to cardiomyocyte replacement therapies for injured myocardium. We discuss advantages and limitations of each particular cell type and suggest directions for future research.
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Skeletal myoblasts
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In contrast to the heart, the skeletal muscle contains precursor cells, referred to either as satellite cells, because of their location, or myoblasts, because of their capacity for self renewal and differentiation; upon muscle injury these cells become activated (3). Because skeletal myoblasts retain the ability to regenerate throughout life and are less sensitive to ischemic injury than cardiac cells, the idea emerged to introduce these cells into the heart to repair the injured myocardium and enhance its function. The potential of these skeletal cells to do cardiac work was confirmed by the biochemical and physiologic plasticity of skeletal muscle induced by electrical depolarization and cardiac engraftment (4–6). Although successful xenogeneic and allogeneic myoblast transplantation has been reported (7,8), the potentially autologous origin of skeletal myoblasts is unlikely to raise any immunologic or ethical problems. The relative ease with which these cells are recognized, cultured, and multiplied in vitro are other properties that make them eligible for clinical use.
Chiu et al. (9) performed myoblast transplantation studies in a cryoinjury model of myocardial infarction (MI) in dogs. The muscle in the implant sites appeared to be mimicking cardiac muscle, including the presence of intercalated discs. Murry et al. (10) engrafted neonatal skeletal myoblasts in cryoinjured rat hearts. By three months, however, although the engrafted cells had formed skeletal muscle, they never expressed cardiac-specific markers, suggesting that there was no cardiac differentiation. Taylor and colleagues (4,5) obtained physiologic improvement by transplantation of autologous skeletal myoblasts and dermal fibroblasts in rabbit heart damaged by cryoinjury. In a study of MI induced by coronary artery ligation in rats, Scorsin and co-investigators (11,12) studied the effect of skeletal myoblast transplantation. Although left ventricular function improved, no gap junctions were detected on the membranes of the skeletal cells, indicating impaired electrical coupling.
Skeletal myoblasts are already being applied clinically. Menasche et al. (13) reported successful implantation of autologous skeletal myoblasts in a 72-year-old HF (New York Heart Association [NYHA] class III) patient. Before treatment, the myocardial scar was characterized as nonreversibly akinetic with absence of viability. After myoblast engraftment, the akinetic wall became contractile and metabolically active, and the ejection fraction increased, changing the patient’s clinical classification to NYHA class II disease within five months of cell transplantation.
In discussions about the limitations of these studies, it is important to note that the skeletal myoblast transplantation in this patient was combined with coronary artery bypass grafting. This immediately puts the functional improvement of the heart in a different light, because the beneficial effects of the bypass surgery may have greatly influenced the improvement of the patient’s clinical situation. Although some of the findings are promising, we do not yet know anything about long-term cell survival and terminal differentiation of myoblasts after transplantation, although a long-term effect of myoblast transplantation on heart structure and function has recently been reported (14). Another important issue is the possible arrhythmogenicity of the transplanted skeletal myoblasts. Their apparent inability to transdifferentiate into cardiomyocytes and to form cardiac-like syncytia with neighboring cells may create a new substrate for ventricular re-entrant arrhythmias because proper functioning of transplanted cells requires coupling with host cardiomyocytes to allow impulse propagation. This could turn every HF patient treated with myoblast transplantation into a candidate for an implantable cardiac defibrillator. The study by Chiu et al. (9) does suggest cardiomyogenic transdifferentiation of myoblasts, but because labeling of the transplanted myoblasts was almost indistinguishable from background tissue, it was impossible to distinguish transplanted cells from recipient tissue unequivocally. Skeletal myoblasts could function by forming electromechanical junctions between cardiomyocytes and skeletal myotubes as observed in vitro by Reinecke and his colleagues (15). However, the transient coupling observed between skeletal myotubes and cardiomyocytes probably reflected gradual down-regulation of connexin 43, which is expressed at high levels in myoblasts. The skeletal cells also possibly could contract in reaction to external mechanical stimuli. However, given the ease with which contractile responses of skeletal cells to mechanical stimuli could be measured, the lack of published data on this suggests that it does not occur. Furthermore, engraftment of the skeletal cells could possibly have influenced the ventricular remodeling process, decreasing fibrosis and increasing hypertrophy of viable cardiomyocytes.
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Embryonic stem cells
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Embryonic stem (ES) cells are derived from the inner cell mass of blastocyst-stage embryos, and in culture they retain the potential for unlimited, undifferentiated proliferation. They are also pluripotent, which means that they are capable of giving rise to every somatic cell type of the adult organism as well as the germ cells (16). Long-term proliferative capacity makes them suitable, in principle, for large-scale culture. Furthermore, because of their capacity to differentiate into cardiomyocytes, human ES cells may furnish the basis of an excellent system for studying human cardiomyocyte physiology and may provide an unlimited supply of cells for the repopulation of damaged myocardium.
Mouse ES cells.
In vitro studies on mouse ES cells have provided much insight into differentiation steps that lead to the development of cells of the mammalian heart (17). To induce differentiation of mouse ES cells into cardiomyocytes, the cells are cultivated in aggregates in suspension to form "embryoid bodies." Spontaneously contracting areas appear in 80% to 100% of embryoid bodies within 10 days, depending on the particular cell line used (Fig. 1) (18,19). A fairly defined sequence of transcription factor expression controls the cardiogenic process in vitro and in vivo (20). Activation of these pathways ultimately leads to the development of heart excitability, myofibrillogenesis, ion channel expression and function, calcium handling, and receptors (21–26). In Figure 2, the sarcomeric banding pattern of mouse ES cell–derived myocytes stained with 
-actinin is shown. As ES cells are capable of differentiating into a wide variety of cell lineages (27), only a small fraction of cells will become cardiomyocytes. For this reason, Klug and colleagues (28) genetically modified mouse ES cells to select cardiomyocytes from mixed cell populations. Expression of a fusion gene in ES cell–derived cardiomyocytes rendered the cells resistant to neomyocin and facilitated the selection with G418 after in vitro differentiation. Non-neomyocin resistant cells were killed in the selection medium. Evidence confirming that G418-selected cells were indeed cardiomyocytes consisted in the expression of sarcomeric myosin immunoreactivity in the absence of immunoreactivity for nebulin, a marker expressed early in skeletal myoblast differentiation but not in cardiac myoblasts. These cultured and genetically selected cardiomyocytes formed stable intracardiac grafts with a normal myocardial structure when transplanted into the healthy ventricular wall of dystrophic mice. The same and other investigators showed that engraftment of fetal cardiomyocytes leads to the formation of intercalated discs and gap junctions (29,30). However, human fetal cells are difficult to obtain, are limited in their ability to divide in culture, and are very sensitive to ischemic injury. Further ethical, political, and practical constraints would always preclude their use in routine therapy.
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Figure 1 (A) Mouse embryonic stem (ES) cells (white arrows) cultured on mouse embryonic fibroblasts (black arrows). (B) Mouse ES cells cultivated in aggregates in suspension to form floating embryoid bodies. (C) Mouse ES cells differentiated into beating muscle (white arrow) on visceral endoderm (black arrow).
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Figure 2 A-actinin immunohistochemical staining, dilution 1:400. Secondary antibody: goat anti-mouse IgG, dilution 1:250.
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Human ES cells.
Recently, human ES cell lines have been described (16,31). Human ES cells are characterized by immortality, expression of specific transcription factors and cell surface molecules, and the ability to form derivatives of all germ layers in vitro and in vivo. Co-culture of one cell line with visceral endoderm-like cells induces differentiation of human ES cells into beating muscle (32). The pluripotent stem cells express a wide variety of receptors for growth factors (33). Two factors, transforming growth factor ß1 and activin-A, are known to promote differentiation into mesodermal derivatives such as muscle cells. Kehat and co-authors (34) clearly showed that one human ES cell line can differentiate into myocytes with properties of cardiomyocytes, with a mononuclear and round or rod-shaped morphology and myofibrillar bundles and intercalated discs. Cardiomyocyte-specific genes and proteins were expressed. A recent study has described conditions under which up to 70% of the human ES-cell derivatives are cardiomyocytes (35).
Before clinical application of ES cells becomes feasible, the following major issues need to be addressed: 1) The allogeneic origin of these cells raises immunological problems, and immunosuppressive drugs could be required to prevent rejection. 2) The efficiency and culture conditions for cardiomyocyte differentiation require optimalization. 3) Nothing is known about cell survival and differentiation after long-term transplantation into ischemic tissue. 4) Stem cells can form cell types other than cardiomyocytes, and because of their immortal state, the potential for tumor development needs to be monitored. 5) Human ES cell biology and research evoke important moral and ethical issues, and this triggers debate throughout the world. In a growing number of countries, legislation is being implemented to ensure that research is properly regulated and controlled.
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Bone marrow stem cells
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Recent attention has focused on bone marrow as a source of stem cells for transplantation into the heart. These cells also retain the capacity for unlimited, undifferentiated proliferation and are capable of developing into different types of cells, including cardiomyocytes (36–41). Different chemicals have been reported to induce differentiation of bone marrow cells into myogenic cells (40,42). Bone marrow, by contrast with ES cells, can be collected from adults and used for transplantation without posing ethical questions or creating problems of tissue matching and rejection.
Makino et al. (38,39) developed an adult bone marrow stromal cell line. These cells turned into myocytes and connected with adjoining cells two weeks after 5-azacytidine treatment. The cells then started beating spontaneously and formed myotube-like structures. The differentiated cells showed a cardiomyocyte-like morphology and cardiomyocyte-specific immunostaining. Moreover, these cells expressed characteristic cardiomyocyte genes and had characteristic action potentials for cardiomyogenic cells, although it is of note that these measurements were carried out at room temperature and that skeletal and cardiac myocytes exhibit similar action potentials under this condition. Adult rat bone marrow cells were also induced by 5-azacytidine to differentiate into myogenic cells expressing troponin I and myosin heavy chain and then were transplanted into cryoinjured myocardium of an isogenic host (43). Muscle-like cells apparently formed in the scar tissue, decreased the transmural scar, stained positively for troponin I, and induced significant improvements in ventricular function. Wang et al. (44) demonstrated that donor bone marrow stromal cells differentiate into cardiomyocytes after being implanted in healthy myocardium. These cells expressed sarcomeric myosin heavy chain and formed gap junctions with host tissue. Orlic et al. (45) described sorting and selection of most multipotent bone marrow cells prior to transplantation in mice. Multipotent bone marrow cells were selected for combined expression of particular cell surface markers. Donor cells were isolated from transgenic mice expressing a green fluorescent protein (46). This protein facilitated identification of the donor cells that were injected into the damaged myocardium of recipient mice shortly after blocking the coronary blood flow. Within nine days, cells with characteristics of cardiomyocytes, smooth muscle cells, and endothelial cells occupied the major part of the damaged area. Cardiac function improved and various myocyte-specific genes were expressed. No long-term analyses were made, however. Jackson and colleagues (47) transplanted a highly enriched stem cell population from adult mouse bone marrow in the bone marrow of lethally irradiated mice after induction of myocardial ischemia. Two weeks after the coronary occlusion, transplanted cells had homed to the myocardial scar where they had formed cardiac myofibers and played a role in neovascularization. Cell homing is the process of cell-to-matrix and cell-to-cell interactions mediated by a variety of cell-adhesion molecules that leads to the anchoring of circulating cells to specific sites in the recipient tissue. Orlic et al. (48) mobilized bone marrow cells in infarcted mice by subcutaneous injection of stem cell factor and granulocyte-colony stimulating factor. A band of newly formed myocardium characterized healing of the infarct, a feature that was absent in non-treated mice. A study by Kocher et al. (49) showed that angioblasts derived from bone marrow stem cells are able to prevent cardiomyocyte apoptosis, reduce remodeling, and improve cardiac function after MI in rats.
Although the results of these experiments were first regarded as spectacular, they recently have been openly criticized. No details about the long-term postoperative survival of the cells were given in any of the engraftment studies. The absence of either a repeat or a long-term follow-up transplantation study of the approach taken by Orlic et al. (45) is of crucial importance. Importantly, because the expression of skeletal cell markers has not been rigorously examined or reported, the identity of bone-marrow derived cardiomyocytes as true cardiomyocytes is still ambiguous. This is emphasized by the expression of skeletal myogenic lineage determining genes in the cardiomyogenic cells in the study by Makino et al. (38). Furthermore, it is difficult to obtain multipotent cells in sufficient quantities, because no specific markers of the true stem cell have been identified. Bone marrow contains only a very small number of these cells, and they are difficult to maintain and to generate in vitro, growing extremely slowly (50). Induction of differentiation into cardiomyocytes is far from efficient. Another issue of concern is the formation of other tissue types instead of muscle cells. If undifferentiated cells are used, transplantation into scarred tissue might induce differentiation into fibroblasts instead of cardiomyocytes, or tumors may develop.
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Directions for future research
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All transplantation studies require rigorous, independent validation, and many basic questions, such as those that follow, need to be addressed before skeletal myoblasts, ES cells, or bone marrow stem cells find their way into routine clinical practice. What will the life span of the cells be after engraftment? How will these cells behave once transplanted? Can they also form cell types that may have detrimental effects on cardiac function, such as fibroblasts or tumor cells? How many cells do we need to transplant, and what is the best way to deliver these cells into the damaged myocardium? Do ES cells need immunosuppression to survive? Do the transplanted cells couple with neighboring cells and propagate impulses properly? Will they adversely affect heartbeat by forming an arrhythmogenic substrate? An important issue in this research is to mark the cells in a proper way. Current failure to label the donor cells adequately and to follow them in vivo makes it very difficult to distinguish them from background tissue and could lead to misinterpretation of the data. Reliable labeling techniques and long-term transplantation studies in animals must provide the necessary insights into cell migration, homing, proliferation, and differentiation. The factors that influence these processes remain to be discovered; so far we have only clues. Depending on the desired effect of transplantation and on the underlying cause of disease, we have to transplant the right cell type(s). Do we need to transplant differentiated cardiomyocytes, or can we use undifferentiated cells if the purpose is to strengthen myocardial function after cell loss due to hypertensive heart disease? In the case of ischemic cell loss, not only do muscle cells need to be replaced but also vascularization has to be restored. Other causes of HF, such as cardiomyopathy, require nothing more than a replacement of non-functioning cells by healthy functional tissue. The different cell types have to be compared extensively to give insight into the correct choice of donor cell. We emphasize that future research requires a clonality assay in order to generate pure cell populations with specific morphologies and functions. Furthermore, we need to explore further the possible existence of a cardiac stem or progenitor cell in the body, able to regenerate myocardial tissue, as reported in a study (51). Ischemia and apoptosis might be of major importance in death of grafted cells, as already suggested (52). With available nuclear imaging techniques, the role of programmed cell death of transplanted cells could be further clarified (53–56). Blocking ischemic influences and preventing initiation of apoptotic pathways has already enhanced donor cell survival (52,57,58). Developing such strategies to prevent ischemic and programmed cell death could be of major importance in making cell transplantation a feasible therapy for cardiac disease. Pharmacologic and genetic anti-death strategies can be distinguished (52,57–60). So far, most cell transplantations have been carried out at the stage of acute MI. The question is whether donor cells also can be introduced into the chronically infarcted area of the heart and whether these areas provide an environment for cells to survive, integrate, and communicate with the host tissue and differentiate into functional cells.
The cellular approach for treating cardiac diseases will bring forth new insights in cardiac development and disease because advances in developmental biology, genetic engineering, and cell transplantation go hand in hand. To optimize the progress in this research area, input from and close cooperation between basic scientists—such as developmental biologists and geneticists, cardiac surgeons, and cardiologists with different sub-specialties including electrophysiology, interventional cardiology, and HF—will be required. Their research should focus on cardiac development as well as cardiac pathologies.
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Conclusions
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In this review, we surveyed results reported in research on cell therapy for cardiac repair. In a very short period of time, substantial progress has been made. Skeletal myoblasts have already been introduced in the clinic in an experimental setting. Stem cells of various sources can be cultured indefinitely and induced to differentiate into cardiomyocytes. Transplantation of these cells in infarcted tissue has demonstrated limited restoration of myocardial structure, improvement of ventricular function, and prevention of myocardial remodeling in animals. In Tables 1 and 2, we summarize the current state of the art of cardiac "engineering," the use of skeletal myoblasts and stem cells, and the characteristics of cardiomyocytes derived from them, respectively (61). However, we are just at the beginning since routine clinical therapy will require considerable fundamental research on the development of appropriate cardiac substrates and on the structure, function, and pathology of cellular transplants. A multidisciplinary approach will be necessary to understand the development of primitive cells from whatever source into a robust three-dimensional cardiac structure, in vivo as well as in vitro. Future investigations must provide more insight into these processes and could lead to engineering of tissue homologues for treatment of cardiac disease. Whether cell transplantation will become an option for treatment of heart disease is not yet clear, as too many gaps in our knowledge still exist. Nevertheless, the promise and prospects for research and disease therapy remain.
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Table 2 Markers of Cardiomyocyte Differentiation from Human Skeletal Myoblasts, Embryonic, and Bone Marrow Stem Cells
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References
|
|---|
- Kajstura J, Leri A, Finato N, et al. Myocyte proliferation in end-stage cardiac failure in humans. Proc Natl Acad Sci U S A. 1998;95:8801–8805[Abstract/Free Full Text]
- Soonpa MH, Kim KK, Pajak L, et al. Cardiomyocyte DNA synthesis and binucleation during murine development. Am J Physiol. 1996;271:H2183–2189
- Mauro A. Satellite cells of skeletal muscle fibers. J Biophys Biochem Cytolog. 1961;9:493–497
- Taylor DA, Atkins BZ, Hungspreugs P, et al. Regenerating functional myocardium: improved performance after skeletal myoblast transplantation. Nat Med. 1998;4:929–933[CrossRef][Medline]
- Hutcheson KA, Atkins BZ, Hueman MT, et al. Comparison of benefits on myocardial performance of cellular cardiomyoplasty with skeletal myoblasts and fibroblasts. Cell Transplant. 2000;9:359–368[Medline]
- Hu P, Yin C, Zhang KM, et al. Transcriptional regulation of the phospholamban gene and translational regulation of SERCA2 gene produces coordinate expression of these two sarcoplasmic reticulum proteins during skeletal muscle phenotype switching. J Biol Chem. 1995;270:11619–11622[Abstract/Free Full Text]
- Van Meter CH, Claycomb WC, Delcarpio JB, et al. Myoblast transplantation in the porcine model: a potential technique for myocardial repair. J Thorac Cardiovasc Surg. 1995;110:1442–1448[Abstract/Free Full Text]
- Gussoni E, Blau HM, Kunkel LM. The fate of individual myoblasts after transplantation into muscles of DMD patients. Nat Med. 1997;3:970–977[CrossRef][Medline]
- Chiu RC-J, Zibaitis A, Kao RL. Cellular cardiomyoplasty: myocardial regeneration with satellite cell implantation. Ann Thorac Surg. 1995;60:12–18[Abstract/Free Full Text]
- Murry CE, Wiseman RW, Schwartz SM, et al. Skeletal myoblast transplantation for repair of myocardial necrosis. J Clin Invest. 1996;98:2512–2523[Medline]
- Scorsin M, Hagege AA, Marotte F, et al. Does transplantation of cardiomyocytes improve function of infarcted myocardium? Circulation. 1997;96(SupplII):188–193
- Scorsin M, Hagege A, Vilquin JT, et al. Comparison of the effects of fetal cardiomyocyte and skeletal myoblast transplantation on postinfarction left ventricular function. J Thorac Cardiovasc Surg. 2000;119:1169–1175[Abstract/Free Full Text]
- Menasche P, Hagege AA, Scorsin M, et al. Myoblast transplantation for heart failure. Lancet. 2001;357:279–280[CrossRef][Medline]
- Ghostine S, Carrion C, Souza LC, et al. Long-term efficacy of myoblast transplantation on regional structure and function after myocardial infarction. Circulation. 2002;106(Suppl 1):I131–136
- Reinecke H, MacDonald GH, Hauschka SD, et al. Electromechanical coupling between skeletal and cardiac muscle. Implications for infarct repair. J Cell Biol. 2000;149:731–740[Abstract/Free Full Text]
- Thomson JA, Itskovitz-Eldor J, Shapiro SS, et al. Embryonic stem cell lines derived from human blastocysts. Science. 1998;282:1145–1147[Abstract/Free Full Text]
- Thorsteinsdottir S, Roelen BA, Goumans MJ, et al. Expression of the alpha 6A integrin splice variant in developing mouse embryonic stem cell aggregates and correlation with cardiac muscle differentiation. Differentiation. 1999;64:173–184[Medline]
- Slager HG, Van Inzen W, Freund E, et al. Transforming growth factor-beta in the early mouse embryo: implications for the regulation of muscle formation and implantation. Dev Genet. 1993;14:212–224[CrossRef][Medline]
- Wobus AM, Wallukat G, Hescheler J. Pluripotent mouse embryonic stem cells are able to differentiate into cardiomyocytes expressing chronotropic responses to adrenergic and cholinergic agents and Ca2+ channel blockers. Differentiation. 1991;48:173–182[CrossRef][Medline]
- Srivastava D, Olson EN. A genetic blueprint for cardiac development. Nature. 2000;407:221–226[CrossRef][Medline]
- Maltsev VA, Wobus AM, Rohwedel J, et al. Cardiomyocytes differentiated in vitro from embryonic stem cells developmentally express cardiac-specific genes and ionic currents. Circ Res. 1994;75:233–244[Abstract/Free Full Text]
- Hescheler J, Fleischmann BK, Lentini S, et al. Embryonic stem cells: a model to study structural and functional properties in cardiomyogenesis. Cardiovasc Res. 1997;36:149–162[Free Full Text]
- Sanchez A, Jones WK, Gulick J, et al. Myosin heavy chain gene expression in mouse embryoid bodies. An in vitro developmental study. J Biol Chem. 1991;266:22419–22426[Abstract/Free Full Text]
- Metzger JM, Lin WI, Johnston RA, et al. Myosin heavy chain expression in contracting myocytes isolated during embryonic stem cell cardiogenesis. Circ Res. 1995;76:710–719[Abstract/Free Full Text]
- Maltsev VA, Ji GJ, Wobus AM, et al. Establishment of beta-adrenergic modulation of L-type Ca2+ current in the early stages of cardiomyocyte development. Circ Res. 1999;84:136–145[Abstract/Free Full Text]
- Viatchenko-Karpinski S, Fleischmann BK, Liu Q, et al. Intracellular Ca2+ oscillations drive spontaneous contractions in cardiomyocytes during early development. Proc Natl Acad Sci U S A. 1999;96:8259–8264[Abstract/Free Full Text]
- Doetschman TC, Eistetter H, Katz M, et al. The in vitro development of blastocyst-derived embryonic stem cell lines: formation of visceral yolk sac, blood islands and myocardium. J Embryol Exp Morphol. 1985;87:27–45[Medline]
- Klug MG, Soonpaa MH, Koh GY, et al. Genetically selected cardiomyocytes from differentiating embryonic stem cells form stable intracardiac grafts. J Clin Invest. 1996;98:216–224[Medline]
- Soonpa MH, Koh GY, Klug MG, et al. Formation of nascent intercalated discs between grafted fetal cardiomyocytes and host myocardium. Science. 1994;264:98–101[Abstract/Free Full Text]
- Leor J, Patterson M, Quinones MJ, et al. Transplantation of fetal myocardial tissue into the infarcted myocardium of rat. A potential method for repair of infarcted myocardium? Circulation. 1996;94(Suppl II):332–336
- Reubinoff BE, Pera MF, Fong CY, et al. Embryonic stem cell lines from human blastocysts: somatic differentiation in vitro. Nat Biotechnol. 2000;18:399–404[CrossRef][Medline]
- Mummery CL, Ward D, Van den Brink CE, et al. Cardiomyocyte differentiation of mouse and human embryonic stem cells. J Anat. 2002;200:233–242[CrossRef][Medline]
- Schuldiner M, Yanuka O, Itskovitz-Eldor J, et al. Effects of eight growth factors on the differentiation of cells derived from human embryonic stem cells. Proc Natl Acad Sci U S A. 2000;97:11307–11312[Abstract/Free Full Text]
- Kehat I, Kenyagin-Karsenti D, Snir M, et al. Human embryonic stem cells can differentiate into myocytes with structural and functional properties of cardiomyocytes. J Clin Invest. 2001;108:407–414[CrossRef][Medline]
- Xu C, Police S, Rao N, et al. Characterization and enrichment of cardiomyocytes derived from human embryonic stem cells. Circ Res. 2002;91:501–508[Abstract/Free Full Text]
- Caplan AI. Mesenchymal stem cells. J Orthop Res. 1991;9:641–650[CrossRef][Medline]
- Pittenger MF, Mackay AM, Beck SC, et al. Multilineage potential of adult human mesenchymal stem cells. Science. 1999;284:143–147[Abstract/Free Full Text]
- Makino S, Fukuda K, Miyoshi S, et al. Cardiomyocytes can be generated from marrow stromal cells in vitro. J Clin Invest. 1999;103:697–705[Medline]
- Fukuda K. Development of regenerative cardiomyocytes from mesenchymal stem cells for cardiovascular tissue engineering. Artif Organs. 2001;25:187–193[CrossRef][Medline]
- Grigoridis AE, Heersche JNM, Aubin JE. Differentiation of muscle, fat, cartilage and bone from progenitor cells present in a bone-derived clonal cell population: effect of dexamethasone. J Cell Biol. 1988;106:2139–2151[Abstract/Free Full Text]
- Prockop DJ. Marrow stromal cells as stem cells for non-hematopoietic tissues. Science. 1997;276:71–74[Abstract/Free Full Text]
- Wakitani S, Saito T, Caplan AI. Myogenic cells derived from rat bone marrow mesenchymal stem cells exposed to 5-azacytidine. Muscle Nerve. 1995;18:1417–1426[CrossRef][Medline]
- Tomita S, Li RK, Weisel RD, et al. Autologous transplantation of bone marrow cells improves damaged heart function. Circulation. 1999;100(Suppl II):247–256
- Wang JS, Shum-Tim D, Galipeau J, et al. Marrow stromal cells for cellular cardiomyoplasty: feasibility and potential clinical advantages. J Thorac Cardiovasc Surg. 2000;129:999–1006
- Orlic D, Kajstura J, Chimenti S, et al. Bone marrow cells regenerate infarcted myocardium. Nature. 2001;410:701–705[CrossRef][Medline]
- Hadjantonakis AK, Gertsenstein M, Ikawa M, et al. Generating green fluorescent mice by germline transmission of green fluorescent ES cells. Mech Dev. 1998;76:79–90[CrossRef][Medline]
- Jackson KA, Majka SM, Wang H, et al. Regeneration of ischaemic cardiac muscle and vascular endothelium by adult stem cells. J Clin Invest. 2001;107:1395–1402[CrossRef][Medline]
- Orlic D, Kajstura J, Chimenti S, et al. Mobilized bone marrow cells repair the infarcted heart, improving function and survival. Proc Natl Acad Sci U S A. 2001;98:10344–10349[Abstract/Free Full Text]
- Kocher AA, Schuster MD, Szabolcs MJ, et al. Neovascularisation of ischemic myocardium by human bone-marrow-derived angioblasts prevents cardiomyocyte apoptosis, reduces remodeling and improves cardiac function. Nat Med. 2001;7:430–436[CrossRef][Medline]
- Verfaillie CM. Can human hematopoietic stem cells be cultured ex vivo? Stem Cells. 1994;12:466–476[Abstract]
- Quaini F, Urbanek K, Beltrami AP, et al. Chimerism of the transplanted heart. N Engl J Med. 2002;346:5–15[Abstract/Free Full Text]
- Zhang M, Methot D, Poppa V, et al. Cardiomyocyte grafting for cardiac repair: graft cell death and anti-death strategies. J Mol Cell Cardiol. 2001;33:907–921[CrossRef][Medline]
- Van Heerde WL, Robert-Offerman S, Dumont E, et al. Markers of apoptosis in cardiovascular tissues: focus on annexin-V. Cardiovasc Res. 2000;45:549–559[Abstract/Free Full Text]
- Blankenberg FG, Katsikis PD, Tait JF, et al. In vivo detection and imaging of phosphatidylserine expression during programmed cell death. Proc Natl Acad Sci U S A. 1998;95:6349–6354[Abstract/Free Full Text]
- Dumont EA, Hofstra L, Van Heerde WL, et al. Cardiomyocyte death induced by myocardial ischemia and reperfusion. Measurement with recombinant human annexin-V in a mouse model. Circulation. 2000;102:1564–1568[Abstract/Free Full Text]
- Dumont EA, Reutelingsperger CP, Smits JF, et al. Real-time imaging of apoptotic cell-membrane changes at the single-cell level in the beating murine heart. Nat Med. 2001;7:1352–1355[CrossRef][Medline]
- Cardone MH, Salvesen GS, Widmann C, et al. The regulation of anoikis: MEKK-1 activation requires cleavage by caspases. Cell. 1997;90:315–323[CrossRef][Medline]
- Fujio Y, Nguyen T, Wencker D, et al. Akt promotes survival of cardiomyocytes in vitro and protects against ischemia-reperfusion injury in mouse heart. Circulation. 2000;101:660–667[Abstract/Free Full Text]
- Morris SD, Cumming DVE, Latchman DS, et al. Specific induction of the 70-kD heat stress proteins by the tyrosine kinase inhibitor herbimycin-A protects rat neonatal cardiomyocytes. A new pharmacological route to stress protein expression? J Clin Invest. 1996;97:706–712[Medline]
- Rakhit RD, Mojet MH, Marber MS, et al. Mitochondria as targets for nitric oxide-induced protection during simulated ischemia and reoxygenation in isolated neonatal cardiomyocytes. Circulation. 2001;103:2617–2623[Abstract/Free Full Text]
- Baroffio A, Hamann M, Bernheim L, et al. Identification of self-renewing myoblasts in the progeny of single human muscle satellite cells. Differentiation. 1996;60:47–57[CrossRef][Medline]
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S. Aharinejad, D. Abraham, P. Paulus, K. Zins, M. Hofmann, W. Michlits, M. Gyongyosi, K. Macfelda, T. Lucas, K. Trescher, et al.
Colony-stimulating factor-1 transfection of myoblasts improves the repair of failing myocardium following autologous myoblast transplantation
Cardiovasc Res,
May 2, 2008;
(2008)
cvn097v2.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. J. Hassink, K. B. Pasumarthi, H. Nakajima, M. Rubart, M. H. Soonpaa, A. B. de la Riviere, P. A. Doevendans, and L. J. Field
Cardiomyocyte cell cycle activation improves cardiac function after myocardial infarction
Cardiovasc Res,
April 1, 2008;
78(1):
18 - 25.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. Trounson
The Production and Directed Differentiation of Human Embryonic Stem Cells
Endocr. Rev.,
April 1, 2006;
27(2):
208 - 219.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. A. Laflamme, J. Gold, C. Xu, M. Hassanipour, E. Rosler, S. Police, V. Muskheli, and C. E. Murry
Formation of Human Myocardium in the Rat Heart from Human Embryonic Stem Cells
Am. J. Pathol.,
September 1, 2005;
167(3):
663 - 671.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. DOLNIKOV, M. SHILKRUT, N. ZEEVI-LEVIN, A. DANON, S. GERECHT-NIR, J. ITSKOVITZ-ELDOR, and O. BINAH
Functional Properties of Human Embryonic Stem Cell-Derived Cardiomyocytes
Ann. N.Y. Acad. Sci.,
June 1, 2005;
1047(1):
66 - 75.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Kofidis, J. L. de Bruin, T. Yamane, M. Tanaka, D. R. Lebl, R.-J. Swijnenburg, I. L. Weissman, and R. C. Robbins
Stimulation of Paracrine Pathways With Growth Factors Enhances Embryonic Stem Cell Engraftment and Host-Specific Differentiation in the Heart After Ischemic Myocardial Injury
Circulation,
May 17, 2005;
111(19):
2486 - 2493.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. BANI, S. NISTRI, T. B. SACCHI, and M. BIGAZZI
Basic Progress and Future Therapeutic Perspectives of Relaxin in Ischemic Heart Disease
Ann. N.Y. Acad. Sci.,
May 1, 2005;
1041(1):
423 - 430.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
L. Formigli, F. Francini, A. Tani, R. Squecco, D. Nosi, L. Polidori, S. Nistri, L. Chiappini, V. Cesati, A. Pacini, et al.
Morphofunctional integration between skeletal myoblasts and adult cardiomyocytes in coculture is favored by direct cell-cell contacts and relaxin treatment
Am J Physiol Cell Physiol,
April 1, 2005;
288(4):
C795 - C804.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Kofidis, J. L. de Bruin, T. Yamane, L. B. Balsam, D. R. Lebl, R.-J. Swijnenburg, M. Tanaka, I. L. Weissman, and R. C. Robbins
Insulin-Like Growth Factor Promotes Engraftment, Differentiation, and Functional Improvement after Transfer of Embryonic Stem Cells for Myocardial Restoration
Stem Cells,
December 1, 2004;
22(7):
1239 - 1245.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
L. G. Futterman and L. Lemberg
Cardiac Repair With Autologous Bone Marrow Stem Cells
Am. J. Crit. Care.,
November 1, 2004;
13(6):
512 - 518.
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Kofidis, J. L. de Bruin, G. Hoyt, D. R. Lebl, M. Tanaka, T. Yamane, C.-P. Chang, and R. C. Robbins
Injectable bioartificial myocardial tissue for large-scale intramural cell transfer and functional recovery of injured heart muscle
J. Thorac. Cardiovasc. Surg.,
October 1, 2004;
128(4):
571 - 578.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Kanno, P. K. M. Kim, K. Sallam, J. Lei, T. R. Billiar, and L. L. Shears II
Nitric oxide facilitates cardiomyogenesis in mouse embryonic stem cells
PNAS,
August 17, 2004;
101(33):
12277 - 12281.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. E. Stec
Smart Gene Therapy for the Heart
Hypertension,
April 1, 2004;
43(4):
720 - 721.
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. L. Steer and S. K. Nigam
Developmental approaches to kidney tissue engineering
Am J Physiol Renal Physiol,
January 1, 2004;
286(1):
F1 - F7.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S.D. Bird, P.A. Doevendans, M.A. van Rooijen, A. Brutel de la Riviere, R.J. Hassink, R. Passier, and C.L. Mummery
The human adult cardiomyocyte phenotype
Cardiovasc Res,
May 1, 2003;
58(2):
423 - 434.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Skeletal myoblasts
