Autologous CXCR4+ Hematopoietic Stem Cells Injected into the Scar Tissue of Chronic Myocardial Infarction Patients Normalizes Tissue Contractility and Perfusion.

BACKGROUND: Chronic myocardial infarction (CMI), represents a public health and a financial burden. Since stem cell transplant is used to regenerate cardiac tissue after acute myocardial infarction. AIM OF THE STUDY: To determine if autologous CXCR4 stem cells could restore damaged myocardial tissue in patients with CMI lesions. METHODS: 20 NYHA grade III male patients with CMI defined by clinical, biochemical, ECG and echocardiographic parameters were included. Patients were treated with G-CSF for 6 d before isolating their autologous stem cells from PBMCs. Cell phenotyping was done by cytofluorometry using monoclonal antibodies (anti-CXCR4, -CD34, -48, -117, -133, -Ki67, -SDF1 and CXCR4); CXCR4 cell subpopulations isolated by sorting were adjusted to 1 × 108 cells by subpopulation and injected in a circular pattern into the cicatrix previously defined by echocardiography. RESULTS: Patients were followed for 6 and 12 months. Six months after cell implant improvements in left ventricle ejection fraction (from 33-50%), stress rate values (from -3/-9% to -18/-22%), stress tests (from 4-12 METS), and the quantity of left ventricle affected segments (3-9) disappeared according to the G-SPECT images. 12 months evaluations did not show significant differences. Interestingly, 3 months after cell implant the ECG showed normal electrical activity in 9 patients whereas after 6 months it was normal in all the patients. CONCLUSIONS: These results ratify that locally injected autologous CXCR4+ bone marrow-derived stem cells have a physiological and a clinical impact in patients with CMI.

Direct cardiac injection of G-CSF mobilized bone-marrow stem-cells improves ventricular function in old myocardial infarction.

Autologous transplant of bone marrow stem cells (BMSC), although extremely useful after acute myocardial events, has not been evaluated in patients with old (>one-year-old) myocardial infarction. Our aim was to determine if CD34(+)-enriched peripheral-blood cells, obtained by apheresis, injected directly into the severely damaged myocardium of five patients with old myocardial infarction could restore depressed myocardial function. We found that 28 weeks after revascularization and peri-infarction injection of the enriched CD34(+) peripheral mononuclear cells, ventricular hemodynamic parameters that included left ventricular ejection fraction, left ventricular diastolic volume, ventricular systolic volume and left ventricular diastolic diameter approximated normal values and there was no restenosis; two patients have been followed for >52 weeks and their parameters are within normal values. In conclusion, intramyocardial injection of easily obtained CD34(+) enriched peripheral blood cells represent an encouraging procedure for patients with severely scarred and dysfunctional myocardium.

Perspectivas de las células tallo en infartos del miocardio / Stem cell perspectives in myocardial infarctions

Myocardial infarction is the leading cause of congestive heart failure and death in industrializated countries. The cellular cardiomyoplasty has emerged as an alternative treatment in the regeneration of infarted myocardial tissue. In animals' models, differents cellular lines such as cardiomyocites, sheletal myoblast, embryonic stem cells and adult mesenchymal stem cells has been used, resulting in an improvement in ventricular function and decrease in amount of infarted tissue. The first three cells line have disvantages as they are allogenics and are difficult to obtain. The adult mesenchymal stem cells are autologous and can be obtained throught the aspiration of bone marrow or from peripherical circulation, prior to stimulating with cytokines (G-CSF). The implantation in humans with recent and old myocardial infarction have shown improvements similar to those shown in animal models. These findings encourage the continued investigation in the mechanism of cellular differentiation and implantation metods in infarted myocardial tissue.

El infarto del miocardio es la principal causa de falla cardiaca y muerte en países industrializados. A la fecha, la cardiomioplastia celular ha emergido como una alternativa en la regeneración de infartos miocárdicos. En modelos animales se han utilizado diferentes líneas celulares como cardiomiocitos fetales, mioblastos de músculo esquelético, células tallo embrionarias y células tallo mesenquimales del adulto, con mejoría en la función ventricular y disminución del área de tejido infartado. Las tres primeras líneas celulares tienen desventajas porque son alogénicas y difíciles de obtener. Las células tallo mesenquimales del adulto son autólogas y se pueden obtener de aspirados de médula ósea o de la circulación periférica previa estimulación con citocinas (G-CSF). La implantación de estas células en seres humanos con infartos del miocardio recientes y antiguos han mostrado mejorías similares a los reportes con modelos animales. Estos hallazgos alientan a continuar la investigación clínica y básica en busca de los mecanismos de diferenciación celular y selección de vías de implantación, en tejido miocárdico infartado.

[Stem cell perspectives in myocardial infarctions]. / Perspectivas de las células tallo en infartos del miocardio.

Myocardial infarction is the leading cause of congestive heart failure and death in industrializated countries. The cellular cardiomyoplasty has emerged as an alternative treatment in the regeneration of infarted myocardial tissue. In animals' models, different cellular lines such as cardiomyocites, skeletal myoblasts, embryonic stem cells and adult mesenchymal stem cells have been used, resulting in an improvement in ventricular function and decrease in amount of infarcted tissue. The first three cells lines have disvantages as they are allogenics and are difficult to obtain. The adult mesenchymal stem cells are autologous and can be obtained throught the aspiration of bone marrow or from peripherical circulation, after stimulating with cytokines (G-CSF). The implantation in humans with recent and old myocardial infarction have shown improvements similar to those shown in animal models. These findings encourage the continued investigation in the mechanism of cellular differentiation and implantation methods in infarcted myocardial tissue.

A subpopulation of large granular von Willebrand Ag negative and CD105 positive endothelial cells, isolated from abdominal aortic aneurysms, overexpress ICAM-1 and Fas antigen.

The aim of this work was to determine whether there is a pre-established basal condition of the endothelial cells isolated from aortic abdominal aneurysm that might augment immune effector mechanisms and thus provide us an insight into the possible causes of aneurysm rupture. Endothelial cells isolated from saccular aortic aneurysm fragments were analyzed by cytofluorometry for the expression of different immune response-related molecules. Our results showed that there is a subpopulation of granule-rich, CD105 positive and von Willebrand antigen negative endothelial cells that have an enhanced basal expression of ICAM-1, and Fas antigen, but, interestingly, no apoptotic bodies were detected. Control endothelial cells derived from healthy areas of the same abdominal aortas did not show such enhanced expression. We conclude that in the endothelium that lines abdominal aorta aneurysms there is, at least, one endothelial cell subpopulation with an apparent inhibition of programmed cell death and in a proinflammatory activation status.

A subpopulation of large granular von Willebrand Ag negative and CD105 positive endothelial cells, isolated from abdominal aortic aneurysms, overexpress ICAM-1 and Fas antigen

The aim of this work was to determine whether there is a pre-established basal condition of the endothelial cells isolated from aortic abdominal aneurysm that might augment immune effector mechanisms and thus provide us an insight into the possible causes of aneurysm rupture. Endothelial cells isolated from saccular aortic aneurysm fragments were analyzed by cytofluorometry for the expression of different immune response-related molecules. Our results showed that there is a subpopulation of granule-rich, CD105 positive and von Willebrand antigen negative endothelial cells that have an enhanced basal expression of ICAM-1, and Fas antigen, but, interestingly, no apoptotic bodies were detected. Control endothelial cells derived from healthy areas of the same abdominal aortas did not show such enhanced expression. We conclude that in the endothelium that lines abdominal aorta aneurysms there is, at least, one endothelial cell subpopulation with an apparent inhibition of programmed cell death and in a proinflammatory activation status.