| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ann Thorac Surg 1995;60:12-18
© 1995 The Society of Thoracic Surgeons
McGill University, Montreal, Quebec, Canada, and East Tennessee State University, Johnson City, Tennessee
 |
Abstract |
|---|
 TopFootnotes Abstract IntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Methods. Two series of canine studies were performed. In the first series (n = 26), satellite cells were isolated from skeletal muscle, cultured, and labeled with tritiated thymidine. The cells were implanted into acutely cryoinjured myocardium and the specimens harvested 4 to 18 weeks later. In the second series (n = 20), satellite cells in culture were labeled with lacZ reporter gene, which encodes production of Escherichia coli ß-galactosidase. Four to 6 weeks later, ß-galactosidase activity was studied using X-Gal stain.
Results. New striated muscles were found in the first series of experiments at the site of implantation, within a dense scar created by cryoinjury. These muscles showed histologic evidence of intercalated discs and centrally located nuclei, similar to those seen in cardiac muscle fibers. Tritiated thymidine radioactivity was not identified clearly, presumably due to dilutional effect as the stem cells replicated repeatedly. In the second series, histochemical studies of reporter gene-labeled and implanted satellite cells revealed the presence of ß-galactosidase within the cells at the implant site, which confirmed the survival of implanted cells.
Conclusions. Our data are consistent with the hypothesis of milieu-influenced differentiation of satellite cells into cardiac-like muscle cells. Confirmation of these findings and its functional capabilities could have important clinical implications.
|
Introduction |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Irreversibly injured cardiac muscle is replaced with fibrous tissue [1]. Adult skeletal muscle, unlike myocardium, has retained an efficient regenerating mechanism. Each mature skeletal myofiber bears a few myogenic cells known as satellite cells (SCs). These myogenic cells remain quiescent and in undifferentiated state under the basal lamina. Injury to skeletal myofibers activates SCs, which enter the mitotic cycle and later fuse with each other and with the injured myofiber, thus restoring continuity and function of the skeletal muscle fiber [2].
We studied the hypothesis that SCs obtained from adult skeletal muscle, when implanted into injured myocardium, will multiply and may be influenced by the cardiac environment to undergo ``milieu-dependent'' differentiation, thus repairing the damaged myocardium.
|
Material and Methods |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Twenty-six and 20 adult mongrel dogs of both sexes weighing 20 to 35 kg were used in the two series of experiments, respectively. As described in detail below, the tibialis anterior muscle was explanted and served as the source of satellite cells. The isolated SCs were cultured in vitro for either 10 days (first experimental group) or 3 weeks (second experimental group) and labeled before being implanted back into acutely cryoinjured myocardium of the same animal. Four to 18 weeks after the implantation, specimens of the heart at the implant sites were obtained and evaluated histologically and histochemically. All animals received humane care, and all experiments were performed according to ``Guide to the Care and Use of Experimental Animals'' of the Canadian Council on Animal Care and the ``Guide for the Care and Use of Laboratory Animals'' (NIH publication 85-23, revised 1985).
Skeletal Muscle Explantation
General anesthesia was induced with intravenous pentobarbital (30 mg/kg intravenously) (M.T.C. Pharmaceuticals, Cambridge, Ont, Canada) and maintained with 1% halothane (M.T.C. Pharmaceuticals) administered through the endotracheal tube. Under sterile conditions a longitudinal incision was made over the projection of the tibialis anterior muscle. The muscle was removed and placed in ice-cold normal saline solution. The operative wound was closed in layers. Animals showed no appreciable handicap after the recovery period.
Satellite Cell Isolation Procedure
Immediately following the explanation procedure excessive connective tissue and fasciae were removed thoroughly from the specimen. The skeletal muscle obtained was rinsed with 70% ethyl alcohol for 30 seconds. Then the muscle tissue was rinsed with 150 mL of Hank's balanced salt solution (Gibco, Grand Island, NY) and minced with scissors until fine pieces of muscle formed a homogeneous mass. After addition of 150 mL Hanks' balanced salt solution, muscle fragments were sedimented in conical 50-mL polypropylene tubes (Corning Inc, Corning, NY) at 540 g for 1 minute. The supernatant then was discarded. This step was repeated two more times. To digest the connective tissue, the specimen was incubated for 15 minutes at 37°C in the shaker bath (Haake SWB 20; Fisher Scientific Ltd, Montreal, Que, Canada) with 1% collagenase (Sigma, St. Louis, MO) and 0.2% type 1-S hyaluronidase (Sigma) in M199 solution (Gibco) supplemented with 5,000 IU/mL penicillin and 5,000 µg/mL streptomycin (Gibco). Remaining muscle mass then was spun down at 540 g for 10 minutes. Connective tissue elements released were aspirated and discarded with the supernatant. The muscle fragments were subjected to further enzymatic digestion using 1% pronase (Sigma) solution at 37°C for 15 minutes to release SCs. The obtained product was sedimented at 540 g for 10 minutes and only the supernatant containing released SCs was saved for further manipulations. Fetal bovine serum (Gibco) was added to the supernatant to halt enzymatic cleavage processes. The remaining tissue debris was separated from cells by spinning the cell suspension at 775 g for 15 minutes. The collected cell pellet was washed and resuspended in the same manner for total of four times.
To purify the cell culture from fibroblasts present in the final cell pellet we used the density centrifugation method described by Yablonka-Reuveni and Nameroff [3]. In brief, the cell suspension was layered on 20% Percoll (Sigma), which itself rested on a 60% Percoll layer. The whole liquid structure was centrifuged at 15,000 g for 5 minutes. The cell layer obtained at the interface of 20% and 60% Percoll concentrations consisted mostly of SCs, whereas the majority of fibroblasts and other cells were situated within other layers at different levels. Retrieved SCs were counted on a hematocytometer, and their viability was assessed by trypan blue exclusion test.
Satellite Cell Plating and Passaging Technique
After the total amount of isolated cells was calculated they were plated on 60-mm polystyrene tissue culture dishes (Corning Inc), which were coated in advance with a layer of laminin (Sigma) to promote SC adherence to the bottom of the culture dish. The plating density ranged from 5.0 x 105 to 7.5 x 105 cells per culture dish. Growth medium (GM), each 100 mL of which contained 82 mL of M199, 7.4 ml of minimum essential medium (Sigma), 10 mL of fetal bovine serum, 5,000 IU/mL of penicillin, 5,000 µg/mL of streptomycin, 250 µL of amphotericin B, and 40 µL of gentamicin, was replaced every 24 to 48 hours. Culture dishes with seeded SCs were maintained in 37°C humidified atmosphere of 95% air with 5% CO2.
In the first series of experiments, to prevent SCs from premature differentiation and fusion in vitro, frequent passaging of cells (every 48 to 72 hours) was carried out. During the passaging procedure, SCs were subjected to a 30-second period of treatment with trypsin (Gibco BRL, Grand Island, NY) diluted ten times in M199. This measure facilitates detachment of cells from the tissue culture dish.
In the second series of experiments, cultured SCs were labeled with pCMVlacZ plasmid and subjected to selection in G418 antibiotic-containing medium. To achieve stable transfection of SCs with DNA plasmid, the in vitro period for SCs was extended to 3 weeks and passaging of cells was carried out every 4 to 5 days.
Satellite Cell Labeling
In the first series of our experiments SCs were labeled with tritiated thymidine (activity, 70 to 80 Ci/mmol; Amersham Life Science Inc, Arlington Heights, IL). The labeling procedure was done on the ninth day after the initial plating, eg, 1 day before SC implantation into the myocardium. Cultured SCs were treated for a period of 20 minutes with GM admixed with tritiated thymidine to a concentration of 10 µCi/mL. Then radioactive GM was washed away and cells again were supplied with nonradioactive GM. Identical radiation pulses of 20 minutes' duration were repeated every 5 hours over a period of 15 hours for a total of four pulses.
In the second series of our project cultured SCs were labeled with an artificially constructed Escherichia coli plasmid pCMVlacZ [4]. This plasmid is of 10.9 kb size and has two genes of interest incorporated in its DNA structure: a reporter gene, lacZ, which encodes for production of bacterial ß-galactosidase, and a neoR gene, which elaborates resistance against neomycin. The E coli lacZ gene was driven by a cytomegalovirus promoter and the neoR gene by Rous sarcoma virus promoter. Transfected cells possessing a marker gene also could be selected against nontransfected cells in GM containing cytotoxic antibiotic G418. To obtain the cloned plasmid from E coli bacteria the QIAGEN plasmid kit was used (QIAGEN Inc, Chatsworth, CA).
For in vitro transfection of SCs we used a lipofection technique [5]. Briefly, for each 60-mm tissue culture dish 10 µg of plasmid DNA and 25 µg of Lipofectin (Gibco) were diluted in two 100-µL amounts of Opti-minimum essential medium reduced serum medium (Gibco BRL), then combined at room temperature for 15 minutes and applied to cells for 18 to 24 hours. For this specific period of time GM fed to cells was being replaced with serum-free minimum essential medium (Gibco BRL) to optimize the transfection efficacy. Growth medium supplemented with serum was administered thereafter.
Seventy-two hours after the lipofection SCs were subjected to selection in GM containing neomycin or antibiotic G418 (Gibco BRL). After the 2-week selection period labeled SCs were collected by brief 30-second trypsinasation and centrifugation at 775 g for 10 minutes. The cells then were resuspended in 0.7 mL of GM and the number of the obtained cells was counted before SCs were implanted shortly thereafter into acutely cryoinjured myocardium.
Cryoinjury of the Myocardium and Satellite Cell Implantation Techniques
The same dog that was the donor of SCs served also as their recipient. General anesthesia was induced and maintained as described before. Left lateral thoracotomy was performed under sterile conditions in the sixth intercostal space. The pericardium was opened and the free wall of the left ventricle was exposed. Before initiation of cryoinjury to the left ventricle, heparin (Leo Laboratories Canada Ltd, Ajax, Ont, Canada) was given intravenously (100 IU/kg) to prevent intramural thrombus formation. For ventricular arrhythmias prevention a lidocaine drip (35 µl • kg-1 • min-1) was administered before the cryoinjury procedure and discontinued 12 hours postoperatively.
To inflict cryoinjury on the heart, we used a copper disk 30 or 50 mm in diameter mounted on a probe cooled by internally circulating liquid nitrogen. The cryosurgery unit type CE-4 (Cooper Surgical, Shelton, CT) was used to deliver liquid nitrogen to the probe and cool the copper disc to -160°C. The disc then was applied firmly to the anterior wall of left ventricle in the zone relatively free from large blood vessels, eg, between the left anterior descending artery and the first diagonal branch of the left anterior descending artery. The cryoinjury time ranged from 20 to 25 minutes. During this procedure arterial blood pressure was monitored and the pressure applied on the left ventricle with cryoprobe was adjusted constantly in response to the changes in the systemic arterial pressure. After the cryoinjury and the rewarming period we easily could recognize the infarcted muscle site, which appeared as a sharply demarcated dark cyanotic area on the surface of the left ventricle. Four channels (two controls and two cell implantation areas) were made in each cryoinjured area. Collected satellite cells (5 to 7.5 x 106 cells resuspended in 0.7 mL of GM) were at that time implanted with a 16-gauge intravenous Teflon catheter (Criticon Inc, Tampa, FL) into the thawed injured myocardium. Both ends of the channels were secured with a 5-0 Prolene suture (Ethicon Ltd, Peterborough, Ont, Canada) to prevent leakage of the implanted cells. Growth medium alone was injected in the control channels. A 5-0 Prolene suture was left within the implant channels to mark the implant site. The pericardium was left open, and the chest was closed in layers.
In addition 13 control animals underwent cryoinjury and sham implantation of GM devoid of cells. The procedures used were the same in the experimental and the sham-operated control groups.
As confirmed later by histologic evaluation, our cryoinsult on the heart was adequate to create a transmural dense homogeneous fibrous scar.
Harvesting of Hearts With the Implant Sites
One day to 14 weeks after implantation dogs were sacrificed under general anesthesia. Their hearts were perfused through the aortic root with 4°C cardioplegic solution at a pressure of 150 mm Hg followed by cold Karnovsky's solution to fix the myocardial tissue. After intracoronary fixation hearts were excised, and the implant sites marked with Prolene sutures were identified and dissected. The recovered specimens were further subjected to 24 hours of fixation in Karnovsky's solution at 4°C. They then were processed for histologic examination to determine the presence of muscle fibers within the implant channels.
The depth and homogeneity of the scar were verified by gross observation and later confirmed by histologic evaluation.
Radioautographic Evaluation of Implant Sites Labeled With Tritiated Thymidine
Hearts with the implants from the first series labeled with tritiated thymidine were subjected to radioautographic evaluation. Clean glass slides were dipped in subbing solution (5 g gelatin and 0.5 g chrome alum per 1,000 mL of water) several times and air dried. The 5-µm-thick tissue sections were mounted on the subbed slide before being coated with liquid emulsion. In a dark room the liquid emulsion (NTB2) was placed in a Coplin jar and warmed to 42°C for an hour to melt the emulsion and to allow the air bubbles to escape. The slide with tissue sections was dipped in the liquid emulsion three times before being air dried. The slides were stored in a sealed light-tight box containing drying agent in a refrigerator during the exposure period. After sample slides were developed to indicate proper exposure time (10 to 15 days), the remaining slides were developed. The developed slides were counterstained with conventional methods as described earlier. The excess emulsion on the back of the slide was removed before microscopic evaluation.
Histochemical Staining of Implanted, Gene-Labeled Satellite Cells
In the second series of experiments specimens obtained from hearts implanted with SCs were fixed as previously described for 60 minutes at 4°C. To reveal the presence of bacterial ß-galactosidase activity tissue samples were stained according to Sanes and associates [6]. In brief, the specimen was placed in a 100-mm tissue culture dish and overlaid with stain solution (20 mmol/L potassium ferricyanide, 20 mmol/L potassium ferrocyanide, and 2 mmol/L MgCl2 [all from Fisher Scientific, Fair Lawn, NJ] in phosphate buffered solution), which was followed with admixture of 1/100 volume of 2% Nonidet P-40 (Sigma) and 1/100 volume of 1% sodium deoxycholate (Sigma). Finally, 1/40 volume of 5-bromo-4-chloro-3-indolyl-ß-D-galactoside substrate diluted in N,N-dimethylformamide (Gibco BRL) was added to the stain compound and the whole complex with the tissue specimen was incubated for 18 hours at 30°C to diminish the background staining [6]. After the histochemical staining for ß-galactosidase activity, the specimens were embedded in paraffin blocks and 5-µm-thick sections were counterstained with hematoxylin and eosin as well as with Masson trichrome.
|
Results |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
). By day 3 the cells were observed to start forming colonies. If left unpassaged, SCs multiplied until they reached confluence by day 5 to 6. Then myogenic cells, which ceased dividing, commenced the fusion process, which resulted in formation of multinucleated myotubes (Fig 2).
|
|
Sacrifice of the experimental animals was carried out at the following intervals: in the first experimental group 3 dogs were sacrificed at 1 day as well as 1, 2, and 4 weeks. Four dogs were sacrificed at 6 weeks, and 5 animals were sacrificed at 8 as well as 14 weeks after implantation. During the second series of experiments, 16 dogs at 4 weeks and 4 dogs at 6 weeks after implantation were sacrificed.
Macroscopic observation and histologic evaluation confirmed transmural fibrous scar of the myocardium at cryoinjured sites. Implantation channels as validated by the presence of Prolene suture were noted to be located 3 to 5 mm below epicardium within the cryoinjury region.
Histologic evaluation of implant sites obtained from hearts of both experimental series revealed the presence of striated muscle fibers in 17 of myocardial tissue specimens (two specimens per dog) obtained from animals sacrificed at 6 and 8 weeks after implantation. In 5 specimens cardiac-muscle–like cells were found within implantation channels as late as 14 weeks after implantation.
Macroscopically (Fig 3) and histologically (Fig 4) as demonstrated by Masson trichrome staining, the muscle fibers within the implant sites were surrounded by dense homogeneous scar. The phenotypic appearance of striated muscle fibers within the implant sites resembled that of cardiac muscle with the presence of intercalated discs and centrally located nuclei (see Fig 4).
|
|
In the second experimental series animals were sacrificed at 4 and 6 weeks after implantation. Histochemical staining of specimens obtained from the hearts implanted with the SCs labeled with lacZ reporter gene revealed the presence of bacterial ß-galactosidase activity within cells in the area of implantation channel, which confirmed the survival of the labeled and implanted cells (Figs 5, 6).
|
|
|
Comment |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
The loss of contractile cells of the heart holds a dismal prognosis for a patient, with the development of congestive heart failure, which bears a considerable mortality over few years. The possibility of adding contractile striated muscle cells would open a new avenue of treatment for patients with congestive heart failure.
Recently Soonpaa and associates [7] reported on successful implantation of fetal cardiac myoblasts into adult mice hearts. The fetal cardiac myoblasts differentiated into cardiac myocytes, forming gap junctions with native myocardium. Similar studies have been carried out using established myoblast cell lines [8]. The clinical applicability of these approaches, however, is remote, for quantitative reasons in the fetal cardiac myoblasts and because of immunologic rejection and oncologic potential in cell lines.
Skeletal muscle, in contrast to myocardium, through the entire life span of the patient retains a population of myogenic cells (satellite cells) that offer a remarkable capacity of regeneration to repair damaged skeletal muscle fibers.
Satellite cells were described in 1961 by Mauro [9], who then suggested that they may be the source of regenerating skeletal muscle nuclei and might play a role in regenerative processes of the muscle. Satellite cells are thought to be myogenic cells normally present in adult muscle fibers and covered by the basal lamina. An injury or stress inflicted on myofiber activates dormant SCs, which then migrate toward the damaged site, where they enter the mitotic cycle and later fuse with each other and also with the ends of damaged myofibers. After fusion, the myoblasts initiate the production of contractile proteins and in this way restore continuity and contractile function of the injured myofiber [2]. Furthermore, it has been shown that the SCs are, up to a certain point (18 to 24 hours), able to withstand an ischemic environment [10]—a feature that may be very valuable for cells involved in muscle repair.
It has not been established yet whether SCs arise from a different myogenic lineage than primary and secondary embryonic myoblasts, or whether they represent an embryologically different myogenic cell lineage. Although adult SCs resemble embryonic myoblasts in their creatine kinase isoenzyme profiles and in the regenerative pathway that mimics ontogenetic development of the skeletal muscle, they are most likely a subpopulation of them [11].
In our study we proposed a hypothesis that myogenic cells obtained from adult skeletal muscle, if implanted into injured myocardium, can undergo ``milieu-influenced differentiation'' and thus become cardiac muscle cells. Results obtained from our first series of animal hearts implanted with satellite cells showed the presence of cardiaclike muscle cells within the implant site surrounded by a homogenous scar. Histologic evaluation revealed muscle fibers within implant sites starting at 6 weeks up to 14 weeks after implantation. Fibers in the implant channels showed striations that are typical for striated muscle. Furthermore, under histologic examination, the muscle cells appeared to be coupled with each other by intercellular junctions resembling gap junctions or intercalated discs. This histologic finding is characteristic of cardiac myocytes.
Unfortunately, most of our radioautographic evaluation of muscle fibers found inside the mature scar showed labeling almost indistinguishable from background (data not shown). Activated SCs undergo many mitotic cycles, comparable with stem cells [12, 13]. Thus, progeny myoblasts that arise after multiple divisions of SCs labeled with definitive quantity of radioactive thymidine might possess only a minimal amount of the label due to ``dilutional effect,'' making them indistinguishable from the background.
Failure to label and follow in vivo the satellite cells within the cryoinjury site prompted us to use artificially constructed DNA plasmid as a marker for SCs. Because of extensive mitotic cycling of SCs, a marker for SCs has to be transmitted to offspring cells without dilution. The bacterial plasmid carrying a reporter gene satisfies such a condition because it can be incorporated into the genome of the host cell and after mitosis will duplicate in daughter cells [4].
Satellite cells that were implanted in the second series of our experiments were labeled with pCMVlacZ plasmid carrying a bacterial reporter gene for ß-galactosidase. Macroscopic evaluation of implant sites from heart specimens stained with X-Gal for the presence of ß-galactosidase activity revealed indigo blue discoloration, which is specific for this histochemical reaction [6] (see Fig 5
). Histologic evaluation of tissue slides stained with X-Gal demonstrated cells within implant sites expressing ß-galactosidase activity (see Fig 6). This finding confirmed the survival of labeled and implanted cells. Taking together the results from both experimental series, our findings are consistent with the hypothesis that SCs may have undergone milieu-influenced differentiation into cardiac-muscle–like cells. Some examples of milieu-induced differentiation have been reported for embryonic, neurogenic, and tumorigenic cells [14, 15].
The cardiac environment is rich with growth factors such as basic fibroblast growth factor, transforming growth factor ß family, insulin growth factors, and others that have been shown greatly to influence growth and differentiation processes of skeletal myoblasts in vitro [16, 17]. Eghbali and associates [18] have demonstrated that cultured cardiac fibroblasts from adult animals under the influence of treatment with transforming growth factor ß can change their phenotypic appearance and acquire some muscle-specific properties. Other factors such as cell–cell adhesion molecules, calcium-dependent adhesion molecules, and integrins also have been implicated in myoblast recognition and fusion [19–21] and might play a role in the differentiation of SCs within the cardiac milieu. There is also a tentative possibility of SC ``rescue'' fusion with damaged cardiac myocytes during the postmitotic period of SCs when they become fusion competent and start producing muscle-specific structural proteins. Some reports indicate that fusion-competent myoblasts or myotubes in certain environment are capable of fusion in vitro with cells of nonmyogenic origin [22]. Thus, fusion between neomyocardium and native myocardium is a possibility, and such a syncytial structure would have important functional implications.
Therefore, at least from the morphologic point of view, the findings of our experimental series so far are consistent with the interpretation that SCs, when implanted into the injured myocardium, can survive and possibly differentiate into cardiac myocytes. Although much remains to be studied and confirmed, we believe this approach is promising and warrants further investigation.
|
Acknowledgments |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Escherichia coli strain with plasmid pCMVlacZ was a kind gift of Dr L. A. Culp from Case Western Reserve University, Cleveland, OH.
The contributions to this project by the following people also are acknowledged: research fellows: Drs Daniel Marelli, Felix Ma, and David Greentree; technician: Minh Duong, BS. Part of studies in the first series of experiments were carried out by Dr Race L. Kao at the Allegheny-Singer Research Institute (Chairman: Dr George Magovern, Sr), Pittsburgh, PA.
|
Footnotes |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Address reprint requests to Dr Chiu, The Montreal General Hospital, C9-169, 1650 Cedar Ave, Montreal, PQ, Canada H3G 1A4.
|
References |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Related Article
This article has been cited by other articles:
|
|
 |
|
  R. Atoui, D. Shum-Tim, and R. C.J. Chiu Myocardial regenerative therapy: immunologic basis for the potential "universal donor cells". Ann. Thorac. Surg., July 1, 2008; 86(1): 327 - 334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. C.J. Chiu The Challenge of "Tending the Bridge" Ann. Thorac. Surg., April 1, 2008; 85(4): 1149 - 1150. [Full Text] [PDF]
|
|
|
|
 |
|
 R. P. Gallegos and R. M. Bolman III Stem Cell Induced Regeneration of Myocardium Card. Surg. Adult, January 1, 2008; 3(2008): 1657 - 1668. [Full Text]
|
|
|
|
 |
|
 M. Khan, V. K. Kutala, D. S. Vikram, S. Wisel, S. M. Chacko, M. L. Kuppusamy, I. K. Mohan, J. L. Zweier, P. Kwiatkowski, and P. Kuppusamy Skeletal myoblasts transplanted in the ischemic myocardium enhance in situ oxygenation and recovery of contractile function Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2129 - H2139. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C.-D. Kan, S.-H. Li, R. D. Weisel, S. Zhang, and R.-K. Li Recipient Age Determines the Cardiac Functional Improvement Achieved by Skeletal Myoblast Transplantation J. Am. Coll. Cardiol., September 11, 2007; 50(11): 1086 - 1092. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Nussbaum, E. Minami, M. A. Laflamme, J. A. I. Virag, C. B. Ware, A. Masino, V. Muskheli, L. Pabon, H. Reinecke, and C. E. Murry Transplantation of undifferentiated murine embryonic stem cells in the heart: teratoma formation and immune response FASEB J, May 1, 2007; 21(7): 1345 - 1357. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Messas, A. Bel, M. C. Morichetti, C. Carrion, M. D. Handschumacher, S. Peyrard, J. T. Vilquin, M. Desnos, P. Bruneval, A. Carpentier, et al. Autologous Myoblast Transplantation for Chronic Ischemic Mitral Regurgitation J. Am. Coll. Cardiol., May 16, 2006; 47(10): 2086 - 2093. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-Y. Min, X. Huang, M. Xiang, A. Meissner, Y. Chen, Q. Ke, E. Kaplan, J. S. Rana, P. Oettgen, and J. P. Morgan Homing of intravenously infused embryonic stem cell-derived cells to injured hearts after myocardial infarction J. Thorac. Cardiovasc. Surg., April 1, 2006; 131(4): 889 - 897. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. E. Murry, L. J. Field, and P. Menasche Cell-Based Cardiac Repair: Reflections at the 10-Year Point Circulation, November 15, 2005; 112(20): 3174 - 3183. [Full Text] [PDF]
|
|
|
|
|
|
P. I. McConnell, C. L. del Rio, D. B. Jacoby, M. Pavlicova, P. Kwiatkowski, A. Zawadzka, J. H. Dinsmore, L. Astra, S. Wisel, and R. E. Michler Correlation of autologous skeletal myoblast survival with changes in left ventricular remodeling in dilated ischemic heart failure J. Thorac. Cardiovasc. Surg., October 1, 2005; 130(4): 1001 - 1001. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. C Chachques, C. Salanson-Lajos, P. Lajos, A. Shafy, A. Alshamry, and A. Carpentier Cellular Cardiomyoplasty for Myocardial Regeneration Asian Cardiovasc Thorac Ann, September 1, 2005; 13(3): 287 - 296. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B.-O. Kim, H. Tian, K. Prasongsukarn, J. Wu, D. Angoulvant, S. Wnendt, A. Muhs, D. Spitkovsky, and R.-K. Li Cell Transplantation Improves Ventricular Function After a Myocardial Infarction: A Preclinical Study of Human Unrestricted Somatic Stem Cells in a Porcine Model Circulation, August 30, 2005; 112(9_suppl): I-96 - I-104. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Hirano, T. Shimono, K. Imanaka-Yoshida, K. Miyamoto, K. Fujinaga, M. Kajimoto, Y. Miyake, M. Nishikawa, T. Yoshida, A. Uchida, et al. Method of Cell Transplantation Promoting the Organization of Intraarterial Thrombus Circulation, August 30, 2005; 112(9_suppl): I-111 - I-116. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Brasselet, M. C. Morichetti, E. Messas, C. Carrion, A. Bissery, P. Bruneval, J.-T. Vilquin, A. Lafont, A. A. Hagege, P. Menasche, et al. Skeletal myoblast transplantation through a catheter-based coronary sinus approach: an effective means of improving function of infarcted myocardium Eur. Heart J., August 1, 2005; 26(15): 1551 - 1556. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Siminiak, D. Fiszer, O. Jerzykowska, B. Grygielska, N. Rozwadowska, P. Kalmucki, and M. Kurpisz Percutaneous trans-coronary-venous transplantation of autologous skeletal myoblasts in the treatment of post-infarction myocardial contractility impairment: the POZNAN trial Eur. Heart J., June 2, 2005; 26(12): 1188 - 1195. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Davani, F. Deschaseaux, D. Chalmers, P. Tiberghien, and J.-P. Kantelip Can stem cells mend a broken heart? Cardiovasc Res, February 1, 2005; 65(2): 305 - 316. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Schuh, S. Breuer, R. Al Dashti, N. Sulemanjee, P. Hanrath, C. Weber, B. F. Uretsky, and E. R. Schwarz Administration of Vascular Endothelial Growth Factor Adjunctive to Fetal Cardiomyocyte Transplantation and Improvement of Cardiac Function in the Rat Model Journal of Cardiovascular Pharmacology and Therapeutics, January 1, 2005; 10(1): 55 - 66. [Abstract] [PDF]
|
|
|
|
|
|
M. Horackova, R. Arora, R. Chen, J. A. Armour, P. A. Cattini, R. Livingston, and Z. Byczko Cell transplantation for treatment of acute myocardial infarction: unique capacity for repair by skeletal muscle satellite cells Am J Physiol Heart Circ Physiol, October 1, 2004; 287(4): H1599 - H1608. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Liu, Q. Hu, Z. Wang, C. Xu, X. Wang, G. Gong, A. Mansoor, J. Lee, M. Hou, L. Zeng, et al. Autologous stem cell transplantation for myocardial repair Am J Physiol Heart Circ Physiol, August 1, 2004; 287(2): H501 - H511. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. F. Pittenger and B. J. Martin Mesenchymal Stem Cells and Their Potential as Cardiac Therapeutics Circ. Res., July 9, 2004; 95(1): 9 - 20. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Toh, S. Kawashima, M. Kawai, T. Sakoda, T. Ueyama, S. Satomi-Kobayashi, S. Hirayama, and M. Yokoyama Transplantation of cardiotrophin-1-expressing myoblasts to the left ventricular wall alleviates the transition from compensatory hypertrophy to congestive heart failure in Dahl salt-sensitive hypertensive rats J. Am. Coll. Cardiol., June 16, 2004; 43(12): 2337 - 2347. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. G. Melo, A. S. Pachori, D. Kong, M. Gnecchi, K. Wang, R. E. Pratt, and V. J. Dzau Molecular and Cell-Based Therapies for Protection, Rescue, and Repair of Ischemic Myocardium: Reasons for Cautious Optimism Circulation, May 25, 2004; 109(20): 2386 - 2393. [Full Text] [PDF]
|
|
|
|
|
|
H. Reinecke, E. Minami, V. Poppa, and C. E. Murry Evidence for Fusion Between Cardiac and Skeletal Muscle Cells Circ. Res., April 2, 2004; 94(6): e56 - e60. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y.-F. Xiao, J.-Y. Min, and J. P. Morgan Immunosuppression and xenotransplantation of cells for cardiac repair Ann. Thorac. Surg., February 1, 2004; 77(2): 737 - 744. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. C. Smits, R.-J. M. van Geuns, D. Poldermans, M. Bountioukos, E. E. M. Onderwater, C. H. Lee, A. P. W. M. Maat, and P. W. Serruys Catheter-Based intramyocardial injection of autologous skeletal myoblasts as a primary treatment of ischemic heart failure: Clinical experience with Six-Month Follow-Up J. Am. Coll. Cardiol., December 17, 2003; 42(12): 2063 - 2069. [Abstract] [Full Text] [PDF]
|
|
