Skip Navigation

European Journal of Heart Failure 2007 9(8):747-753; doi:10.1016/j.ejheart.2007.03.008
This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (8)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Tse, H.-F.
Right arrow Articles by Lau, C.-P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tse, H.-F.
Right arrow Articles by Lau, C.-P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2007 European Society of Cardiology

Paracrine effects of direct intramyocardial implantation of bone marrow derived cells to enhance neovascularization in chronic ischaemic myocardium

Hung-Fat Tsea,*, Chung-Wah Siua, Shu-Guang Zhua, Liao Songyana, Qing-Yong Zhanga, Wing-Hon Laia, Yok-Lam Kwongb, John Nichollsc and Chu-Pak Laua

a Division of Cardiology, The University of Hong Kong, Queen Mary Hospital Hong Kong, China
b Division of Hematology, The University of Hong Kong, Queen Mary Hospital Hong Kong, China
c Department of Pathology, The University of Hong Kong, Queen Mary Hospital Hong Kong, China

* Corresponding author. Cardiology Division, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China. Tel.: +852 2855 3598; fax: +852 2818 6304. E-mail address: hftse{at}hkucc.hku.hk


   Abstract
Top
 Abstract
1. Introduction
 2. Methods
 3. Results
 4. Discussion
 References
 
Objective: To determine the optimal bone marrow (BM) cell types, and their potential mechanisms of action for neovascularization in chronic ischaemic myocardium.

Methods and results: The functional effects, angiogenic potential and cytokine expression of direct intramyocardial implantation of autologous BM CD31-positive endothelial progenitor cells (EPC, n=9), BM mononuclear cells (MNCs, n=9), and saline (n=9) were compared in a swine model of chronic ischaemic myocardium. Autologous BM cells were harvested and catheter-based electromechanical mapping-guided direct intramyocardial injection was performed to target ischaemic myocardium. After 12 weeks, injection of BM-MNC resulted in significant improvements in left ventricular dP/dt (+21±8%, P=0.032), left ventricular pressure (+17±4%, P=0.048) and regional microsphere myocardial perfusion over ischaemic endocardium (+74±28%, P<0.05) and epicardium (+73±29%, P<0.05). No significant effects were observed following injection of BM-EPC or saline. Capillary density (1132±69 versus 903±44 per mm2, P=0.047) and expression of mRNA of vascular endothelial growth factor (VEGF, 32.3±5.6 versus 13.1±3.7, P<0.05,) and angiopoietin-2 (23.9±3.6 versus 13.7±3.1, P<0.05) in ischaemic myocardium was significantly greater in the BM-MNC group than the saline group. The capillary density in ischaemic myocardium demonstrated a significant positive correlation with VEGF expression (r=0.61, P<0.001).

Conclusion: Catheter-based direct intramyocardial injection of BM-MNC enhanced angiogenesis more effectively than BM-EPC or saline, possibly via a paracrine effect, with increased expression of VEGF that subsequently improved cardiac performance of ischaemic myocardium.

Key Words: Bone marrow • Ischaemic myocardium • Neovascularization

Received October 31, 2006; Revised February 24, 2007; Accepted March 19, 2007


   1. Introduction
Top
 Abstract
 1. Introduction
2. Methods
 3. Results
 4. Discussion
 References
 
Despite recent advances in medical therapy and coronary revascularization techniques for the treatment of coronary artery disease (CAD), they are unsuccessful in a significant proportion of patients with persistent myocardial ischaemia who continue to experience anginal symptoms that are refractory to medical therapy [1,2]. Such patients require alternative therapeutic strategies to enhance neovascularization. Experimental studies have demonstrated that bone marrow (BM)-derived progenitor cells can be mobilized and incorporated into sites of active ischaemia to augment neovascularization [3-5]. Therapeutic delivery of BM cells into chronic ischaemic myocardium has therefore been investigated. In large animal models of chronic myocardial ischaemia, direct intramyocardial injection of BM cells increases collateral flow, capillary density and regional contractility [6-8]. In most pilot clinical trials that involved patients with chronic myocardial ischaemia [9-13], BM mononuclear cells (MNC) were used as they are easily obtained and require no special techniques for isolation. Nonetheless there is little published information comparing different cellular treatment strategies: the optimal cell type to enhance neovascularization remains to be determined.

Among different subpopulations, BM-derived endothelial progenitor cells (EPCs) have been proposed to play an important role in enhancing neovascularization via trans-differentiation into endothelial cells at ischaemic sites [3,4,14]. In this study, we aimed to define the functional role of BM-MNC and BM-EPC, by comparing their efficacy in enhancing neovascularization in chronic ischaemic myocardium. We also tested the hypothesis that neovascularization is related to the in situ expression of different angiogenic cytokines after local transplantation of different populations of autologous BM-derived cells.


   2. Methods
Top
 Abstract
 1. Introduction
 2. Methods
3. Results
 4. Discussion
 References
 
2.1. Porcine model of chronic myocardial ischaemia
Adult minipigs (Guangdong, China) weighing 45 to 50 kg underwent ameroid constrictor (Research Instruments SW, USA) implantation around the proximal left circumflex (LCX) artery to induce chronic myocardial ischaemia [15,16]. Animals were anesthetized with ketamine (15 mg/kg IM) and maintained by inhalation of 1.5% isoflurane. An ameroid constrictor was placed around the proximal portion of the LCX artery via a left thoracotomy to gradually induce total occlusion of the artery over a 4-week period without causing myocardial infarction. This animal experiment was approved by the Committee on the Use of Live Animals in Teaching & Research of the University of Hong Kong.

2.2. Study protocol
Eight weeks following implantation, animals that showed total occlusion of LCX artery without myocardial infarction, and evidence of chronic myocardial ischaemia, as detected by left ventricular (LV) electromechanical mapping (NOGA, Biosense-Webster), were selected for study. A total of 27 animals were randomized to undergo intramyocardial injection of BM-MNC (n=9); BM CD31-positive EPC (n=9) or saline control (n=9). Immediately before and 12 weeks after injection, all animals underwent invasive measurement of LV haemodynamics using a micromanometer catheter (Millar Instruments, Houston TX). Coloured microspheres were also injected into the left atrium to assess regional myocardial blood flow. Animals were sacrificed 12 weeks after intramyocardial injection for histological and immunohistochemical assessment to examine the in vivo effect of treatment on the ischaemic myocardium.

2.3. Electroanatomical mapping and direct intramyocardial injection
Non-fluoroscopic LV electromechanical mapping (NOGA system, Biosense-Webster, Diamond Bar, CA, USA) was performed to identify the foci of ischaemic myocardium [6,9,11]. After completion of LV electromechanical mapping, the mapping catheter was replaced by a modified mapping catheter incorporated with a 27G needle at the tip (Myostar, Biosense-Webster) for direct endomyocardial injection. A total of 15 injections were made into areas of hibernating ischaemia as documented by LV electroanatomical mapping (Fig. 1). Each injection consisted of 0.1 mL of BM-MNC, BM-EPC, or saline delivered via a 1-mL syringe. The operators were blinded to the type of injection given.


Figure 01
View larger version (45K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 1 Electromechanical mapping of chronic ischaemic myocardium over left circumflex artery region to guide catheter-based direct intramyocardial injection. The red area on the linear local shortening map (right) indicates an area of decreased wall motion with preserved unipolar voltage (yellow-green colour, left), suggestive of ischaemic myocardium. The black dots show sites of direct intramyocardial injection.

 
2.4. Preparation of autologous BM-derived cells
Eight weeks after placement of the ameroid constrictor, animals were anesthetized with ketamine (15 mg/kg IM) and 60 mL of BM blood aspirated from the ileum. BM-MNCs were isolated by Ficoll density gradient centrifugation [9]. BM cells were washed twice in phosphate buffered saline, re-suspended in phosphate buffered saline enriched with 10% autologous plasma to 1x107 MNCs per mL, and returned directly to the laboratory for use. Cell sorting of BM-EPC was performed using MACS bead selection method for CD31 (BD Pharmingen, USA), because anti-swine CD34 or CD133 antibody was not available [8]. BM-EPC were re-suspended in phosphate buffered saline enriched with 10% autologous plasma for injection. BM suspensions were tested by flow cytometry (Elite, Beckman Coulter, Fullerton, CA, USA) with directly conjugated antibodies against CD31 (BD Pharmingen, USA). Cell viability was >95% in all BM preparations.

2.5. Measurement of regional myocardial blood flow (MBF)
Regional MBF was measured with coloured microspheres (Dye-Trak, Triton Technology, USA) before and 8 weeks following ameroid implantation, and 12 weeks following direct intramyocardial injection [17]. Coloured microspheres were injected into the left atrium and a reference arterial blood sample aspirated from the descending aorta at a constant rate of 20 mL/min for 60 s using a withdrawal pump. Coloured microspheres from the LV wall and blood samples were digested by potassium hydroxide, and their dyes extracted with dimethylformamide (200 µL). The concentration of dyes was measured by spectrophotometry and MBF (mL/min per gram) of the endocardial and epicardial region of the lateral (LCX region) LV wall was determined [17].

2.6. Reverse-transcription polymerase chain reaction (RT-PCR)
Frozen tissue samples from the ischaemic LV wall (LCX region) were homogenized and RNA extracted using a total RNA kit (Ambion, Austin, Texas). Gene expressions were detected by polymerase chain reaction following reverse transcription. In brief, 1 µg of total RNA was used in 20 µL reverse transcription reaction, mixed with 0.5 µg random hexamer and then reverse-transcribed into cDNA by Superscript II Reverse Transcriptase (Gibco BRL, Rockville, MD) according to the manufacturer's instructions. After reverse transcription, 1 µL of the product was subsequently used for PCR amplification using primers for vascular endothelial growth factor (VEGF, forward: 5'CCT GGT GGA CAT CTT CCA GGA3'; backward: 5'GAA GCT CAT CTC TCC TAT GTG3'); fibroblast growth factor-2 (FGF-2, forward: 5'GCT ATG AAG GAA GAT GGA3'); backward: 5'CAG TTC GTT TCA GTG CCA3'); and angiopoietin-2 (Ang-2, forward: 3'GGC AGC TTG TTT TCT TCG CT5'; backward: 5'CTG ATA CTG CCT CTT CCC CG3'). The amplification of the 18S gene was used as an internal control (QuantumRNA– Universal 18S Internal Standard, Ambion, Texas) [18]. Levels of mRNA expression were quantified by the UV-gel documentation system (BioRad, Hercules, CA). Validation of the semi-quantitative RT-PCR was performed using normal porcine heart cDNA to ensure that there was no interaction between two pairs of primers; the reaction condition was also standardized for different amounts of cDNA.

2.7. Immunohistochemical staining
Paraffin sections (4 µm) were cut from the ischaemic LV wall (LCX region), deparaffinised, rehydrated and incubated in 10% normal Goat serum (Vector Lab, Burlingane, CA). A rabbit polyclonal antibody against von Willebrand factor (vWF, 1:200 respectively, Chemicon, Temecula, CA) was then added and incubated at 4 °C overnight. After blocking in 3% H2O2 in methanol, positive staining was visualized using the Dako Envision–+ kit (Dako, Glodtrup, Denmark) and DAB as a substrate. Capillary density was measured by the number of positive vWF stained cells in 10 randomly selected fields from the ischaemic area at 400x magnification, and was expressed as the number per mm2. All measurements were counted in a blinded fashion.

2.8. Statistical analysis
Based on the data of similar previous studies using BM cells [6-8], it was determined that a minimum of 8 animals in each treatment group would be required to show a 16% difference in myocardial perfusion with 80% power and a 0.05 two-sided significance level. Data were expressed as mean±1 standard error of the mean (SEM). Statistical comparisons were performed with Student's t test as appropriate. Comparisons between different groups were performed using one way ANOVA followed by Bonferroni multiple comparison. Calculations were performed using SPSS software (version 13.0). A P value<0.05 was considered statistically significant.


   3. Results
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
4. Discussion
 References
 
3.1. BM-MNC, BM-EPC and control
Flow cytometry analysis revealed no significant difference in the number of CD31+ cells in the preparation of BM-MNC (7.0±2.1x105 cells per mL) and BM EPC (7.7±3.3x105 cells, P=0.80). Nonetheless the mean total number of cells injected in the BM-MNC group was significantly higher than in the BM-EPC group (1.6±0.4x107 cells versus 1.4±0.8x106 cells, P<0.01). Saline was substituted for the BM preparation in the control group.

3.2. Effects of BM therapy on global myocardial function
Acute haemodynamic assessment showed no significant differences between the BM-EPC, BM-MNC and control group in LV pressure (Fig. 2A), LV end-diastolic pressure (Fig. 2B), LV dP/dt (Fig. 2C) or heart rate (Fig. 2D) 8 weeks after ameroid implantation (baseline, all P>0.05). There were also no significant changes in LV end-diastolic pressure and heart rate in all three groups 12 weeks after injections (Fig. 2B and D). Nonetheless, LV pressure was significantly increased in the BM MNC group 12 weeks after injections compared with baseline (+17±4%, P=0.048), but not in the BM EPC (+8±3%, P=0.12) or control groups (+2±2%, P=0.94) (Fig. 2A). LV dP/dt was significantly increased in the BM-MNC group 12 weeks after injection compared with baseline (+21±8%, Fig. 2C, P=0.032), but not in the BM-EPC (–1±3%, P=0.50) or control groups (+3±8%, P=0.98) (Fig. 2C). The LV dP/dt was thus significantly higher in the BM-MNC group (1590±58 mm Hg/s) 12 weeks after injection (P<0.001) compared with the BM-EPC group (1258±43 mm Hg/s) and control group (1277±92 mm Hg/s).


Figure 02
View larger version (14K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 2 Serial changes in invasive measurement of left ventricular dP/dt before (pre) and 12 weeks after (post) direct intramyocardial injection of bone marrow endothelial progenitor cells (BM-EPC), bone marrow mononuclear cells (BM-MNC) and saline.

 
3.3. Effects of BM therapy on myocardial blood flow
At 8 weeks after ameroid implantation, regional MBFs in the endocardium and epicardium at the ischaemic LCX region were reduced by an equal extent in all 3 groups: BM-MNC (–33±6%), BM-EPC (–29±4%), and control injection (–31±7%) (P>0.05). There were no significant differences in the regional MBFs in the endocardium and epicardium between the three groups at the ischaemic LCX region after ameroid placement (Fig. 3). After injection of BM-MNC, regional MBFs were significantly increased in the endocardium (from 1.74±0.26 to 2.79±0.38 mL/min per gram, +74±28%, P<0.05) and in the epicardium (from 1.70±0.26 to 2.91±0.41 mL/min per gram, +73±29%, P<0.05) of the ischaemic myocardium compared with baseline (Fig. 3). BM-EPC injection improved, but did not significantly increase, regional MBFs in the endocardium (from 1.66±0.33 to 2.33±0.58 mL/min per gram, +59±30%, P=0.31) and epicardium (from 1.59±0.35 to 2.16±0.65 mL/min per gram, +40±23%, P=0.23) of the ischaemic myocardium (Fig. 3). In contrast, saline injection did not change regional MBFs in the endocardium (from 1.66±0.27 to 1.65±0.33 mL/min per gram, +7.9±12%, P>0.05) or epicardium (from 1.73±0.36 to 1.60±0.28 mL/min per gram, –1.0±12%, P>0.05) in the ischaemic myocardium (Fig. 3).


Figure 03
View larger version (12K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 3 Serial changes in regional myocardial perfusion as measured by coloured microspheres over ischaemic epicardium and endocardium before (pre) and 12 weeks after (post) direct intramyocardial injection of bone marrow endothelial progenitor cells (BM-EPC), bone marrow mononuclear cells (BM-MNC) and saline.

 
3.4. Effects of BM therapy on capillary density and cytokine expression in the ischaemic myocardium
Immunohistochemical staining revealed a significantly higher number of vWF-positive capillaries in the BM-MNC compared with the control group (1132±69 versus 903±44 per mm2, P=0.047) (Fig. 4A). Compared with BM-EPC or saline injection, BM-MNC injection into the ischaemic myocardium resulted in significant upregulation of mRNA expression of VEGF (32.3±5.6 versus 19.3±2.7 and 13.1±3.7, P<0.05, Fig. 4B) and Ang-2 (23.9±3.6 versus 11.1±3.8 and 13.7±3.1, P<0.05, Fig. 4C), but not FGF-2 (5.4±0.5 versus 6.5±0.9 and 5.2±0.5, P>0.05, Fig. 4D). Nonetheless there were no significant differences in the mRNA expression of VEGF, Ang-2 and FGF-2 in the non-ischaemic myocardium at the left anterior descending artery region between the three groups (data not shown). Finally, there was a significant positive correlation of capillary density with mRNA expression of VEGF (r=0.61, P<0.001, Fig. 5), but not with mRNA expression of Ang-2 (r=0.28, P=0.082) or FGF-2 (r=0.30, P=0.13)


Figure 04
View larger version (19K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 4 A. Capillary density in ischaemic myocardium from swine 12 weeks after direct intramyocardial injection of bone marrow endothelial progenitor cells (BM-EPC), bone marrow mononuclear cells (BM-MNC) and saline. Expression of mRNA of vascular endothelial growth factor (B, VEGF); fibroblast growth factor-2 (C, FGF-2); and angiopoietin-2 (D, Ang-2) as measured by reverse transcription polymerase chain reaction in ischaemic myocardium from swine.

 


Figure 05
View larger version (11K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 5 Correlation between capillary density and expression of vascular endothelial growth factor (VEGF) mRNA in ischaemic myocardium from swine (r=0.61, 95% confidence interval [CI] 0.30-0.81, P<0.001).

 
3.5. Effects of number of BM cells injected
In the BM-MNC and BM-EPC groups, there was no significant relationship between the total number of BM cells injected and change in LV dP/dt (r=0.18, P=0.47) or capillary density (r=0.08, P=0.72). Similarly, there was no significant relationship between the total number of CD31+ve cells injected and change in LV dP/dt (r=0.06, P=0.82) and capillary density (r=0.04, P=0.86).


   4. Discussion
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
References
 
The increasing number of patients with severe coronary artery disease in whom conventional revascularization treatment has failed [1,2] has led to the investigation of different types of stem cell therapy for therapeutic angiogenesis [19]. Although BM-derived progenitor cells have failed to fulfil the initial promise to regenerate the damaged myocardium in experimental [20,21] and clinical studies [22,23], their efficacy in improving myocardial perfusion and preventing LV remodelling has been repeatedly demonstrated [6-8,24-26]. These therapeutic benefits are likely due to the enhancement of neovascularization by BM cells [3-5]. Several different types of stem/progenitor cells can be isolated from BM. Nevertheless the relative angiogenic efficacy of intramyocardial delivery of different types of BM cells remains unclear.

We compared two different strategies of catheter-based direct intramyocardial injection of BM-derived cells, viz., BM-MNC and BM-EPC, that are currently employed in ongoing randomized clinical trials [19]. In the majority of clinical trials [9-13,25,26], BM-MNC have been tested as the need for extensive ex vivo manipulation of BM with respect to cell isolation and expansion is avoided. Furthermore, the use of a combination of different types of BM cells may provide additional synergistic effects to enhance neovascularization [5,6]. An alternative approach is to isolate specific populations of BM cells according to their expression of surface antigen. Among different subpopulations of BM progenitor cells, BM-EPCs play an important role in the augmentation of neovascularization after ischaemic insult as well as re-endothelialization of injured endothelium [3,4,27]. As a result, BM-EPCs enriched from BM-MNCs are also being investigated in clinical trials for therapeutic angiogenesis [19].

The results of this study demonstrated that catheter-based direct intramyocardial injection of BM-MNC was more effective than BM-EPC or saline in enhancing neovascularization and improving LV function in chronic ischaemic myocardium. Direct intramyocardial injection of BM-MNC to the ischaemic myocardium was associated with upregulation of in vivo mRNA expression of VEGF and Ang-2. These local changes in cytokine expression, especially VEGF, resulted in increased capillary density and regional MBF in the chronic ischaemic myocardium, and improved LV function. In contrast, direct intramyocardial injection of BM-EPC led to only a modest increase in VEGF expression, capillary density and regional MBF at the chronic ischaemic myocardium compared with saline injection, and did not improve LV function. The inclusion of a control arm in this study provided evidence that needle injury alone does not contribute to neovascularization.

In this study, CD31+BM-MNC instead of CD34+ cells were used to represent BM-EPC. Kawamoto et al. [8] demonstrated that direct intramyocardial injection of CD31-positive MNC, but not CD31-negative MNC, enhances neovascularization and improves LV function in chronic ischaemic myocardium. Using a similar animal model of chronic myocardial ischaemia and catheter-based electromechanical guided direct intramyocardial injection; we showed that intramyocardial delivery of BM-MNC was more effective than BM-EPC in enhancement of neovascularization and improving LV function. In contrast to previous studies [8], there was no significant improvement in LV function after intramyocardial injection of BM-EPC, despite a modest improvement in regional MBF and capillary density. The reason remains unclear although differences in the method of BM cell preparation and the number of BM-EPC injected may account for the discrepant findings. In the present study, we prepared EPC from the BM-MNC without overnight culture and did not perform further selection of non-adhesive CD31-positive cells. Our results did not demonstrate any significant relationship between the total number of BM cells or CD31+ve cells and changes in LV function or capillary density. Nonetheless the total number of CD31-positive cells injected was much lower than those used in a previous study [8]. The use of a higher concentration/number of CD31-positive cells might exert a more profound effect: recent experimental studies have shown a significant dose-dependent effect of BM-EPC in the enhancement of neovascularization [28]. However, the potential risk of injecting a high concentration of purified BM-EPC has not been clearly addressed [19,29]. The preparations of BM-EPC and BM-MNC in this study were aimed at simulating those used in current clinical trials.

Our findings provide an important mechanistic insight into the use of BM-derived cells to enhance neovascularization. Despite a similar number of CD31-positive cells in the BM-MNC and BM-EPC preparation, injection of BM-MNC into ischaemic myocardium was associated with a higher local expression of VEGF and Ang-2. This resulted in increased capillary density and regional MBF compared with that achieved with BM-EPC. These results are consistent with previous findings [5,6] and provide further evidence to suggest that other BM subpopulations within the BM-MNC, including haematopoietic stem cells and mesenchymal stem cells, are a rich source of angiogenic growth factors that contribute to neovascularization via a paracrine effect in ischaemic myocardium. We also observed a direct relationship between local expression of VEGF and capillary density that suggests a pivotal role for VEGF in enhancing neovascularization after BM injection. Recent experimental studies in a genetically engineered mouse model have confirmed the paracrine effects of BM-derived progenitor cells in ischaemic myocardium by increasing local VEGF and Ang-2 expression [30]. Both VEGF and Ang-2 are critical for postnatal neovascularization. Increased expression of Ang-2 enhances the responsiveness of endothelial cells to VEGF and promotes neovascularization [31].

These data provide a functional and mechanistic foundation for the use of catheter-based direct intramyocardial delivery of freshly isolated BM-MNC as a therapeutic strategy to induce neovascularization in patients with chronic ischaemic myocardium. It remains to be seen whether further ex vivo expansion and isolation of BM derived progenitor cells can improve the angiogenic efficacy.


   Acknowledgement
 
This study was supported by the Sun Chieh Yeh Heart Foundation Fund, S. K. Yee Medical Foundation Grant (Project No. 203217), and The Research Grants Council of Hong Kong (HKU 7357/02M) from Hong Kong.


   References
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
 References
 

  1. Mannheimer C., Camici P., Chester M.R., et al. The problem of chronic refractory angina; report from the ESC Joint Study Group on the Treatment of Refractory Angina. Eur Heart J (2002) 23:355–370.[Free Full Text]
  2. Laham R.J., Baim D.S. No-option patients: a growing problem. In: Angiogenesis and direct myocardial revascularization—Laham R.J., Baim D.S., eds. (2005) Totowa, NJ: Humana Press. 1–18.
  3. Asahara T., Murohara T., Sullivan A., et al. Isolation of putative progenitor endothelial cells for angiogenesis. Science (1997) 275:964–967.[Abstract/Free Full Text]
  4. Isner J.M., Asahara T. Angiogenesis and vasculogenesis as therapeutic strategies for postnatal neovascularization. J Clin Invest (1999) 103:1231–1236.[Web of Science][Medline]
  5. Kinnaird T., Stabile E., Burnett M.S., Epstein S.E. Bone-marrow-derived cells for enhancing collateral development: mechanisms, animal data, and initial clinical experiences. Circ Res (2004) 95:354–363.[Abstract/Free Full Text]
  6. Fuchs S., Baffour R., Zhou Y.F., et al. Transendocardial delivery of autologous bone marrow enhances collateral perfusion and regional function in pigs with chronic experimental myocardial ischemia. J Am Coll Cardiol (2001) 37:1726–1732.[Abstract/Free Full Text]
  7. Kamihata H., Matsubara H., Nishiue T., et al. Improvement of collateral perfusion and regional function by implantation of peripheral blood mononuclear cells into ischemic hibernating myocardium. Arterioscler Thromb Vasc Biol (2002) 22:1804–1810.[Abstract/Free Full Text]
  8. Kawamoto A., Tkebuchava T., Yamaguchi J., et al. Intramyocardial transplantation of autologous endothelial progenitor cells for therapeutic neovascularization of myocardial ischemia. Circulation (2003) 107:461–468.[Abstract/Free Full Text]
  9. Tse H.F., Kwong Y.L., Lo G., et al. Angiogenesis in ischemic myocardium by intramyocardial autologous bone marrow mononuclear cell implantation. Lancet (2003) 361:47–49.[CrossRef][Web of Science][Medline]
  10. Fuchs S., Satler L.F., Kornowski R., et al. Catheter-based autologous bone marrow myocardial injection in no-option patients with advanced coronary artery disease: a feasibility study. J Am Coll Cardiol (2003) 41:1721–1724.[Abstract/Free Full Text]
  11. Perin E.C., Dohmann H.F., Borojevic R., et al. Transendocardial, autologous bone marrow cell transplantation for severe, chronic ischemic heart failure. Circulation (2003) 107:2294–2302.[Abstract/Free Full Text]
  12. Briguori C., Briguori C., Reimers B., et al. Direct intramyocardial percutaneous delivery of autologous bone marrow in patients with refractory myocardial angina. Am Heart J (2006) 151:674–680.[CrossRef][Web of Science][Medline]
  13. Beeres S.L., Bax J.J., Kaandorp T.A., et al. Usefulness of intramycoardial injection of autologous bone marrow-derived mononuclear cells in patients with severe angina pectoris and stress-induced myocardial ischemia. Am J Cardiol (2006) 97:1326–1331.[CrossRef][Web of Science][Medline]
  14. Kalka C., Masuda H., Takahashi T., et al. Transplantation of ex vivo expanded endothelial progenitor cells for therapeutic neovascularization. Proc Natl Acad Sci U S A (2000) 97:3422–3427.[Abstract/Free Full Text]
  15. O'Konski M.S., White F.C., Longhurst J., Roth D., Bloor C.M. Ameroid constriction of the proximal left circumflex coronary artery in swine: a model of limited coronary collateral circulation. Am J Cardiovasc Pathol (1987) 1:69–77.[Medline]
  16. Roth D.M., Maruoka Y., Rogers J., et al. Development of coronary collateral circulation in left circumflex ameroid-occluded swine myocardium. Am J Physiol (1987) 253:H1279–H1288.[Web of Science][Medline]
  17. Prinzen F.W., Bassingthwaighte J.B. Blood flow distributions by microsphere deposition methods. Cardiovasc Res (2000) 45:13–21.[Abstract/Free Full Text]
  18. Malhi H., Bronk S.F., Werneburg N.W., Gores G.J. Free fatty acids induce JNK dependent hepatocyte lipoapoptosis. J Biol Chem (2006) 311:1118–1123.
  19. Boyle A.J., Schulman S.P., Hare J.M., Oettgen P. Controversies in cardiovascular medicine: ready for the next step. Circulation (2006) 114:339–352.[Free Full Text]
  20. Balsam L.B., Wagers A.J., Christensen J.L., et al. Haematopoietic stem cells adopt mature haematopoietic fates in ischaemic myocardium. Nature (2004) 428:668–673.[CrossRef][Medline]
  21. Nygren J.M., Jovinge S., Breitbach M., et al. Bone marrow-derived hematopoietic cells generate cardiomyocytes at a low frequency through cell fusion, but not transdifferentiation. Nat Med (2004) 10:494–501.[CrossRef][Web of Science][Medline]
  22. Janssens S., Dubois C., Bogaert J., et al. Autologous bone marrow-derived stem-cell transfer in patients with ST-segment elevation myocardial infarction: double-blind, randomised controlled trial. Lancet (2006) 367:113–121.[CrossRef][Web of Science][Medline]
  23. Meyer G.P., Wollert K.C., Lotz J., et al. Intracoronary bone marrow cell transfer after myocardial infarction: eighteen months' follow-up data from the randomized, controlled BOOST (BOne marrOw transfer to enhance ST-elevation infarct regeneration) trial. Circulation (2006) 113:1287–1294.[Abstract/Free Full Text]
  24. Murry C.E., Soonpaa M.H., Reinecke H., et al. Haematopoietic stem cells do not transdifferentiate into cardiac myocytes in myocardial infarcts. Nature (2004) 428:664–668.[CrossRef][Medline]
  25. Schachinger V., Erbs S., Elsasser A., et al. Intracoronary bone marrow-derived progenitor cells in acute myocardial infarction. N Engl J Med (2006) 355:1210–1221.[Abstract/Free Full Text]
  26. Assmus B., Honold J., Schachinger V., et al. Transcoronary transplantation of progenitor cells after myocardial infarction. N Engl J Med (2006) 355:1222–1232.[Abstract/Free Full Text]
  27. Urbich C., Dimmeler S. Endothelial progenitor cells: characterization and role in vascular biology. Circ Res (2004) 95:343–353.[Abstract/Free Full Text]
  28. Iwasaki H., Kawamoto A., Ishikawa M., et al. Dose-dependent contribution of CD34-positive cell transplantation to concurrent vasculogenesis and cardiomyogenesis for functional regenerative recovery after myocardial infarction. Circulation (2006) 113:1311–1325.[Abstract/Free Full Text]
  29. Oettgen P., Boyle A.J., Schulman S.P., Hare J.M. Controversies in cardiovascular medicine. Circulation (2006) 114:353–358.[Free Full Text]
  30. Fazel S., Cimini M., Chen L., et al. Cardioprotective c-kit+ cells are from the bone marrow and regulate the myocardial balance of angiogenic cytokines. J Clin Invest (2006) 116:1865–1877.[CrossRef][Web of Science][Medline]
  31. Hanahan D. Signaling vascular morphogenesis and maintenance. Science (1997) 277:48–50.[Abstract/Free Full Text]

Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Eur J Heart FailHome page
L. Fan, C. Lin, S. Zhuo, L. Chen, N. Liu, Y. Luo, J. Fang, Z. Huang, Y. Lin, and J. Chen
Transplantation with survivin-engineered mesenchymal stem cells results in better prognosis in a rat model of myocardial infarction
Eur J Heart Fail, November 1, 2009; 11(11): 1023 - 1030.
[Abstract] [Full Text] [PDF]

Home page
 Eur Heart JHome page
J. J. Gavira, E. Nasarre, G. Abizanda, M. Perez-Ilzarbe, A. de Martino-Rodriguez, J. A. Garcia de Jalon, M. Mazo, A. Macias, I. Garcia-Bolao, B. Pelacho, et al.
Repeated implantation of skeletal myoblast in a swine model of chronic myocardial infarction
Eur. Heart J., August 22, 2009; (2009) ehp342v1.
[Abstract] [Full Text] [PDF]

Home page
 Ann. Thorac. Surg.Home page
Q. Zhao, Y. Sun, L. Xia, A. Chen, and Z. Wang
Randomized Study of Mononuclear Bone Marrow Cell Transplantation in Patients With Coronary Surgery
Ann. Thorac. Surg., December 1, 2008; 86(6): 1833 - 1840.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
M. Perez-Ilzarbe, O. Agbulut, B. Pelacho, C. Ciorba, E. S. Jose-Eneriz, M. Desnos, A. A. Hagege, P. Aranda, E. J. Andreu, P. Menasche, et al.
Characterization of the paracrine effects of human skeletal myoblasts transplanted in infarcted myocardium
Eur J Heart Fail, November 1, 2008; 10(11): 1065 - 1072.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (8)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Tse, H.-F.
Right arrow Articles by Lau, C.-P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tse, H.-F.
Right arrow Articles by Lau, C.-P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?