Nuestros investigadores

Beatriz Pelacho Samper

Publicaciones científicas más recientes (desde 2010)

Autores: Herrero D; Cañón S; Pelacho, Beatriz; et al.
ISSN 1079-5642  Vol. 39  Nº 3  2019  págs. E106 - E106
Autores: Ivars, Marta; España, Agustín, (Autor de correspondencia); et al.
ISSN 1365-2133  2019  págs. 1 - 11
Autores: Garbayo, Elisa; Mazo, Manuel María; et al.
ISSN 0022-3565  Vol. 370  Nº 3  2019  págs. 761 - 771
Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are a promising cell source for cardiac repair after myocardial infarction (MI) because they offer several advantages such as potential to remuscularize infarcted tissue, integration in the host myocardium, and paracrine therapeutic effects. However, cell delivery issues have limited their potential application in clinical practice, showing poor survival and engraftment after transplantation. In this work, we hypothesized that the combination of hiPSC-CMs with microparticles (MPs) could enhance long-term cell survival and retention in the heart and consequently improve cardiac repair. CMs were obtained by differentiation of hiPSCs by small-molecule manipulation of the Wnt pathway and adhered to biomimetic poly(lactic-co-glycolic acid) MPs covered with collagen and poly(D-lysine). The potential of the system to support cell survival was analyzed in vitro, demonstrating a 1.70-fold and 1.99-fold increase in cell survival after 1 and 4 days, respectively. The efficacy of the system was tested in a mouse MI model. Interestingly, 2 months after administration, transplanted hiPSC-CMs could be detected in the peri-infarct area. These cells not only maintained the cardiac phenotype but also showed in vivo maturation and signs of electrical coupling. Importantly, cardiac function was significantly improved, which could be attributed to a paracrine effect of cells. These findings suggest that MPs represent an excellent platform for cell delivery in the field of cardiac repair, which could also be translated into an enhancement of the potential of cell-based therapies in other medical applications.
Autores: de Juan, María Elena; prosper f; et al.
ISSN 1932-6254  Vol. 12  Nº 4  2018  págs. 1012 - 1019
Tissue-specific stem cells reside in a specialized environment known as niche. The niche plays a central role in the regulation of cell behaviour and, through the concerted action of soluble molecules, supportive somatic cells, and extracellular matrix components, directs stem cells to proliferate, differentiate, or remain quiescent. Great efforts have been done to decompose and separately analyse the contribution of these cues in the in vivo environment. Specifically, the mechanical properties of the extracellular matrix influence many aspects of cell behaviour, including self-renewal and differentiation. Deciphering the role of biomechanics could thereby provide important insights to control the stem cells responses in a more effective way with the aim to promote their therapeutic potential. In this review, we provide a wide overview of the effect that the microenvironment stiffness exerts on the control of cell behaviour with a particular focus on the induction of stem cells differentiation. We also describe the process of mechanotransduction and the molecular effectors involved. Finally, we critically discuss the potential involvement of tissue biomechanics in the design of novel tissue engineering strategies
Autores: prosper f; Pelacho, Beatriz, (Autor de correspondencia)
ISSN 1422-0067  Vol. 19  Nº 10  2018  págs. E3236
Coronary heart disease is the leading cause of death worldwide with huge socio-economic consequences. Cell therapy, and particularly mesenchymal stem cells (MSC), are considered a promising option to treat this disorder, due to their robust trophic and immunomodulatory properties. However, limitations such as their low rate of engraftment and poor survival after administration into the heart have precluded their large-scale clinical use. Nevertheless, the combination of MSC with polymer-made scaffolds or hydrogels has proven to enhance their retention and, therefore, their efficacy. Additionally, their allogeneic use could permit the creation of ready-to-use cell patches able to improve their feasibility and promote their application in clinical settings. In this review, the experimental and clinical results derived from the use of MSC in cardiac pathology, as well as advances in the bioengineering field to improve the potential of therapeutic cells, are extensively discussed. Additionally, the current understanding of the heart response to the allogeneic MSC transplants is addressed.
Autores: Castellano, D.; Sanchis, A.; Blanes, M.; et al.
ISSN 1932-6254  Vol. 12  Nº 2  2018  págs. E983 - E994
Human dermo-epidermal skin equivalents (DE) comprising in vitro expanded autologous keratinocytes and fibroblasts are a good option for massive burn treatment. However, the lengthy expansion time required to obtain sufficient surface to cover an extensive burn together with the challenging surgical procedure limits their clinical use. The integration of DE and biodegradable scaffolds has been proposed in an effort to enhance their mechanical properties. Here, it is shown that poly(hydroxybutyrate) electrospun scaffolds (PHB) present good biocompatibility both in vitro and in vivo and are superior to poly-epsilon-caprolactone electrospun scaffolds as a substrate for skin reconstruction. Implantation of PHB scaffolds in healthy rats polarized macrophages to an M2-type that promoted constructive in vivo remodelling. Moreover, implantation of DE-PHB composites in a NOD/SCID mouse xenograft model resulted in engraftment accompanied by an increase in angiogenesis that favoured the survival of the human graft. Thus, PHB scaffolds are an attractive substrate for further exploration in skin reconstruction procedures, probably due in part to their greater angiogenic and M2 macrophage polarization properties. Copyright (c) 2017 John Wiley & Sons, Ltd.
Autores: Herrero, D.; Canon, S. ; Pelacho, Beatriz; et al.
ISSN 1079-5642  Vol. 38  Nº 9  2018  págs. 2160 - 2173
Objective Cardiac progenitor cells reside in the heart in adulthood, although their physiological relevance remains unknown. Here, we demonstrate that after myocardial infarction, adult Bmi1(+) (B lymphoma Mo-MLV insertion region 1 homolog [PCGF4]) cardiac cells are a key progenitor-like population in cardiac neovascularization during ventricular remodeling. Approach and Results These cells, which have a strong in vivo differentiation bias, are a mixture of endothelial- and mesenchymal-related cells with in vitro spontaneous endothelial cell differentiation capacity. Genetic lineage tracing analysis showed that heart-resident Bmi1(+) progenitor cells proliferate after acute myocardial infarction and differentiate to generate de novo cardiac vasculature. In a mouse model of induced myocardial infarction, genetic ablation of these cells substantially deteriorated both heart angiogenesis and the ejection fraction, resulting in an ischemic-dilated cardiac phenotype. Conclusions These findings imply that endothelial-related Bmi1(+) progenitor cells are necessary for injury-induced neovascularization in adult mouse heart and highlight these cells as a suitable therapeutic target for preventing dysfunctional left ventricular remodeling after injury.
Autores: Pelacho, Beatriz; López, A; Inoges S; et al.
ISSN 0195-668X  Vol. 39  Nº Supl. 1  2018  págs. 1196 - 1196
Autores: Collantes M; Pelacho, Beatriz; Garcia-Velloso, Maria Jose; et al.
ISSN 1479-5876  Vol. 15  Nº 1  2017  págs. 56
PET/CT imaging of 18F-FDG-labeled CSC allows quantifying biodistribution and acute retention of implanted cells in a clinically relevant pig model of chronic myocardial infarction. Similar levels of acute retention are achieved when cells are IM or IC administered. However, acute cell retention does not correlate with cell engraftment, which is improved by IM injection.
Autores: Garbayo, Elisa; Gavira, Juan José; García de Yébenes, Manuel; et al.
ISSN 2045-2322  Vol. 6  2016  págs. 25932
Cardiovascular protein therapeutics such as neuregulin (NRG1) and acidic-fibroblast growth factor (FGF1) requires new formulation strategies that allow for sustained bioavailability of the drug in the infarcted myocardium. However, there is no FDA-approved injectable protein delivery platform due to translational concerns about biomaterial administration through cardiac catheters. We therefore sought to evaluate the efficacy of percutaneous intramyocardial injection of poly(lactic-co-glycolic acid) microparticles (MPs) loaded with NRG1 and FGF1 using the NOGA MYOSTAR injection catheter in a porcine model of ischemia-reperfusion. NRG1- and FGF1-loaded MPs were prepared using a multiple emulsion solvent-evaporation technique. Infarcted pigs were treated one week after ischemia-reperfusion with MPs containing NRG1, FGF1 or non-loaded MPs delivered via clinically-translatable percutaneous transendocardial-injection. Three months post-treatment, echocardiography indicated a significant improvement in systolic and diastolic cardiac function. Moreover, improvement in bipolar voltage and decrease in transmural infarct progression was demonstrated by electromechanical NOGA-mapping. Functional benefit was associated with an increase in myocardial vascularization and remodeling. These findings in a large animal model of ischemia-reperfusion demonstrate the feasibility and efficacy of using MPs as a delivery system for growth factors and provide strong evidence to move forward with clinical studies using therapeutic proteins combined with catheter-compatible biomaterials.
Autores: Dauwe, D.; Pelacho, Beatriz; Wibowo, A.; et al.
ISSN 2047-9980  Vol. 5  Nº 4  2016  págs. e002288
BOECs can be successfully culture-expanded from patients with ICMP. In contrast to impaired functionality of ICMP-derived bone marrow MNCs, BOECs retain a robust proangiogenic profile, both in vitro and in vivo, with therapeutic potential for targeting ischemic disease.
Autores: Anitua, E.; Pelacho, Beatriz; Prado, R. ; et al.
ISSN 0168-3659  Vol. 202  2015  págs. 31 - 39
PRGF is a platelet concentrate within a plasma suspension that forms an in situ-generated fibrin-matrix delivery system, releasing multiple growth factors and other bioactive molecules that play key roles in tissue regeneration. This study was aimed at exploring the angiogenic and myogenic effects of PRGF on in vitro endothelial cells (HUVEC) and skeletal myoblasts (hSkMb) as well as on in vivo mouse subcutaneously implanted matrigel and on limb muscles after a severe ischemia. Human PRGF was prepared and characterized. Both proliferative and anti-apoptotic responses to PRGF were assessed in vitro in HUVEC and hSkMb. In vivo murine matrigel plug assay was conducted to determine the angiogenic capacity of PRGF, whereas in vivo ischemic hind limb model was carried out to demonstrate PRGF-driven vascular and myogenic regeneration. Primary HUVEC and hSkMb incubated with PRGF showed a dose dependent proliferative and anti-apoptotic effect and the PRGF matrigel plugs triggered an early and significant sustained angiogenesis compared with the control group. Moreover, mice treated with PRGF intramuscular infiltrations displayed a substantial reperfusion enhancement at day 28 associated with a fibrotic tissue reduction. These findings suggest that PRGF-induced angiogenesis is functionally effective at expanding the perfusion capacity of the new vasculature and attenuating the endogenous tissue fibrosis after a severe-induced skeletal muscle ischemia. (C) 2015 Elsevier B.V. All rights reserved.
Autores: Ruiz-Villalba, A.; Pogontke, C. ; et al.
ISSN 0735-1097  Vol. 65  Nº 19  2015  págs. 2057 - 2066
BACKGROUND Although efforts continue to find new therapies to regenerate infarcted heart tissue, knowledge of cellular and molecular mechanisms involved remains poor. OBJECTIVES This study sought to identify the origin of cardiac fibroblasts (CFs) in the infarcted heart to better understand the pathophysiology of ventricular remodeling following myocardial infarction (MI). METHODS Permanent genetic tracing of epicardium-derived cell (EPDC) and bone marrow-derived blood cell (BMC) lineages was established using Cre/LoxP technology. In vivo gene and protein expression studies, as well as in vitro culture assays, were developed to characterize EPDC and BMC interaction and properties. RESULTS EPDCs, which colonize the cardiac interstitium during embryogenesis, massively differentiate into CFs MI. This response is disease-specific, because angiotensin II-induced pressure overload does not trigger significant fibroblastic differentiation. The expansion of epicardial-derived CFs follows BMC infiltration into the infarct site; the number of EPDCs equals that of BMCs 1 week post-infarction. BMC-EPDC interaction leads to cell polarization, massive collagen deposition, and scar formation. Moreover, epicardium-derived CFs display stromal properties with respect to BMCs, contributing to the sustained recruitment of circulating cells to the damaged zone and the cardiac persistence of hematopoietic progenitors/stem cells after MI. CONCLUSIONS EPDCs, but not BMCs, are the main origin of CFs in the ischemic heart. Adult resident EPDC contribution to the CF compartment is time-and disease-dependent. Our findings are relevant to the understanding of postventricular remodeling and may contribute to the development of new therapies to treat this disease. (C) 2015 by the American College of Cardiology Foundation.
Autores: Pelacho, Beatriz; Sancho, Ana; et al.
ISSN 1937-3341  Vol. 21  Nº 43017  2015  págs. 1633 - 1641
Substrate stiffness, biochemical composition, and matrix topography deeply influence cell behavior, guiding motility, proliferation, and differentiation responses. The aim of this work was to determine the effect that the stiffness and protein composition of the underlying substrate has on the differentiation of induced pluripotent stem (iPS) cells and the potential synergy with specific soluble cues. With that purpose, murine iPS-derived embryoid bodies (iPS-EBs) were seeded on fibronectin- or collagen I-coated polyacrylamide (pAA) gels of tunable stiffness (0.6, 14, and 50 kPa) in the presence of basal medium; tissue culture polystyrene plates were employed as control. Specification of iPS cells toward the three germ layers was analyzed, detecting an increase of tissue-specific gene markers in the pAA matrices. Interestingly, soft matrix (0.6 kPa) coated with fibronectin favored differentiation toward cardiac and neural lineages and, in the case of neural differentiation, the effect was potentiated by the addition of specific soluble factors. The generation of mature astrocytes, neural cells, and cardiomyocytes was further proven by immunofluorescence and transmission electron microscopy. In summary, this work emphasizes the importance of using biomimetic matrices to accomplish a more specific and mature differentiation of stem cells for future therapeutic applications.
Autores: Baumgartner, S.; Rodriguez-Madoz, Juan Roberto; et al.
ISSN 1547-3287  Vol. 24  Nº 4  2015  págs. 484 - 496
Stem cell-derived cardiomyocytes (CMs) are often electrophysiologically immature and heterogeneous, which represents a major barrier to their in vitro and in vivo application. Therefore, the purpose of this study was to examine whether Neuregulin-1 beta (NRG-1 beta) treatment could enhance in vitro generation of mature "working-type" CMs from induced pluripotent stem (iPS) cells and assess the regenerative effects of these CMs on cardiac tissue after acute myocardial infarction (AMI). With that purpose, adult mouse fibroblast-derived iPS from alpha-MHC-GFP mice were derived and differentiated into CMs through NRG-1 beta and/or dimethyl sulfoxide (DMSO) treatment. Cardiac specification and maturation of the iPS was analyzed by gene expression array, quantitative real-time polymerase chain reaction, immunofluorescence, electron microscopy, and patch-clamp techniques. In vivo, the iPS-derived CMs or culture medium control were injected into the peri-infarct region of hearts after coronary artery ligation, and functional and histology changes were assessed from 1 to 8 weeks post-transplantation. On differentiation, the iPS displayed early and robust in vitro cardiogenesis, expressing cardiac-specific genes and proteins. More importantly, electrophysiological studies demonstrated that a more mature ventricular-like cardiac phenotype was achieved when cells were treated with NRG-1 beta and DMSO compared with DMSO alone. Furthermore, in vivo studies demonstrated that iPS-derived CMs were able to engraft and electromechanically couple to heart tissue, ultimately preserving cardiac function and inducing adequate heart tissue remodeling. In conclusion, we have demonstrated that combined treatment with NRG-1 beta and DMSO leads to efficient differentiation of iPS into ventricular-like cardiac cells with a higher degree of maturation, which are capable of preserving cardiac function and tissue viability when transplanted into a mouse model of AMI.
Autores: Araña, M; Gavira, Juan José; Pena, E. ; et al.
ISSN 0142-9612  Vol. 35  Nº 1  2014  págs. 143 - 151
Although transplantation of adipose-derived stem cells (ADSC) in chronic myocardial infarction (MI) models is associated with functional improvement, its therapeutic value is limited due to poor long-term cell engraftment and survival. Thus, the objective of this study was to examine whether transplantation of collagen patches seeded with ADSC could enhance cell engraftment and improve cardiac function in models of chronic MI. With that purpose, chronically infarcted Sprague-Dawley rats (n = 58) were divided into four groups and transplanted with media, collagen scaffold (CS), rat ADSC, or CS seeded with rat ADSC (CS-rADSC). Cell engraftment, histological changes, and cardiac function were assessed 4 months after transplantation. In addition, Gottingen minipigs (n = 18) were subjected to MI and then transplanted 2 months later with CS or CS seeded with autologous minipig ADSC (CS-pADSC). Functional and histological assessments were performed 3 months post-transplantation. Transplantation of CS-rADSC was associated with increased cell engraftment, significant improvement in cardiac function, myocardial remodeling, and revascularization. Moreover, transplantation of CS-pADSC in the pre-clinical swine model improved cardiac function and was associated with decreased fibrosis and increased vasculogenesis. In summary, transplantation of CS-ADSC resulted in enhanced cell engraftment and was associated with a significant improvement in cardiac function and myocardial remodeling. (C) 2013 Elsevier Ltd. All rights reserved.
Autores: Castellano, D. ; Blanes, M. ; Marco, B.; et al.
ISSN 1547-3287  Vol. 23  Nº 13  2014  págs. 1479 - 1490
The development of biomaterials for myocardial tissue engineering requires a careful assessment of their performance with regards to functionality and biocompatibility, including the immune response. Poly(3-hydroxybutyrate) (PHB), poly(e-caprolactone) (PCL), silk, poly-lactic acid (PLA), and polyamide (PA) scaffolds were generated by electrospinning, and cell compatibility in vitro, and immune response and cardiac function in vitro and in vivo were compared with a noncrosslinked collagen membrane (Col) control material. Results showed that cell adhesion and growth of mesenchymal stem cells, cardiomyocytes, and cardiac fibroblasts in vitro was dependent on the polymer substrate, with PHB and PCL polymers permitting the greatest adhesion/growth of cells. Additionally, polymer substrates triggered unique expression profiles of anti- and pro-inflammatory cytokines in human peripheral blood mononuclear cells. Implantation of PCL, silk, PLA, and PA patches on the epicardial surface of healthy rats induced a classical foreign body reaction pattern, with encapsulation of polymer fibers and induction of the nonspecific immune response, whereas Col and PHB patches were progressively degraded. When implanted on infarcted rat heart, Col, PCL, and PHB reduced negative remodeling, but only PHB induced significant angiogenesis. Importantly, Col and PHB modified the inflammatory response to an M2 macrophage phenotype in cardiac tissue, indicating a more beneficial reparative process and remodeling. Collectively, these results identify PHB as a superior substrate for cardiac repair.
Autores: Andreu, Ion; Luque, T.; Sancho, Ana; et al.
ISSN 1742-7061  Vol. 10  Nº 7  2014  págs. 3235 - 3242
Infarcted hearts are macroscopically stiffer than healthy organs. Nevertheless, although cell behavior is mediated by the physical features of the cell niche, the intrinsic micromechanical properties of healthy and infarcted heart extracellular matrix (ECM) remain poorly characterized. Using atomic force microscopy, we studied ECM micromechanics of different histological regions of the left ventricle wall of healthy and infarcted mice. Hearts excised from healthy (n = 8) and infarcted mice (n = 8) were decellularized with sodium dodecyl sulfate and cut into 12 gm thick slices. Healthy ventricular ECM revealed marked mechanical heterogeneity across histological regions of the ventricular wall with the effective Young's modulus ranging from 30.2 +/- 2.8 to 74.5 +/- 8.7 kPa in collagen- and elastin-rich regions of the myocardium, respectively. Infarcted ECM showed a predominant collagen composition and was 3-fold stiffer than collagen-rich regions of the healthy myocardium. ECM of both healthy and infarcted hearts exhibited a solid-like viscoelastic behavior that conforms to two power-law rheology. Knowledge of intrinsic micromechanical properties of the ECM at the length scale at which cells sense their environment will provide further insight into the cell-scaffold interplay in healthy and infarcted hearts.
Autores: Pelacho, Beatriz; Garbayo, Elisa; et al.
ISSN 0168-3659  Vol. 173  2014  págs. 132 - 139
Acidic fibroblast growth factor (FGF1) and neuregulin-1 (NRG1) are growth factors involved in cardiac development and regeneration. Microparticles (MPs) mediate cytokine sustained release, and can be utilized to overcome issues related to the limited therapeutic protein stability during systemic administration. We sought to examine whether the administration of microparticles (MPs) containing FGF1 and NRG1 could promote cardiac regeneration in a myocardial infarction (MI) rat model. We investigated the possible underlying mechanisms contributing to the beneficial effects of this therapy, especially those linked to endogenous regeneration. FGF1- and NRG1-loaded MPs were prepared using a multiple emulsion solvent evaporation technique. Seventy-three female Sprague-Dawley rats underwent permanent left anterior descending coronary artery occlusion, and MPs were intramyocardially injected in the peri-infarcted zone four days later. Cardiac function, heart tissue remodeling, revascularization, apoptosis, cardiomyocyte proliferation, and stem cell homing were evaluated one week and three months after treatment. MPs were shown to efficiently encapsulate FGF1 and NRG1, releasing the bioactive proteins in a sustained manner. Three months after treatment, a statistically significant improvement in cardiac function was detected in rats treated with growth factor-loaded MPs (FGF1, NRG1, or FGF1/NRG1). The therapy led to inhibition of cardiac remodeling with smaller infarct size, a lower fibrosis degree and induction of tissue revascularization. Cardiomyocyte proliferation and progenitor cell recruitment were detected. Our data support the therapeutic benefit ofNRG1 and FGF1 when combined with protein delivery systems for cardiac regeneration. This approach could be scaled up for use in pre-clinical and clinical studies. (C) 2013 Elsevier B.V. All rights reserved.
Autores: Perez-Pomares, J. M.; Ruiz-Villalba, A.; et al.
ISSN 0008-6363  Vol. 103  Nº Supl. 1  2014  págs. S63
Myocardial infarction is a prevalent cardiovascular disease. Mechanisms of repair in the post-infarcted heart include a progressive fibrosis that severely affects cardiac performance, eventually leading to cardiac failure. Cardiac fibrosis in the context of ventricular remodeling after infarction depends on fibroblasts of the cardiac interstitium (cardiac fibroblasts), a heterogeneous population of cells which, upon interaction with other interstitial cell types, initiates a massive deposition of extracellular matrix promoting the formation of a characteristic scar. In this work we have studied the cellular components of the cardiac interstitium from the embryo to the adult. Our results show that Wilms tumor supresor (Wt1) positive epicardial-derived mesenchymal cells pioneer the formation of the cardiac interstitium along embryogenesis, followed by the peri- and post-natal incorporation of bone-marrow derived cells. Adult epicardial-derived cells robustly differentiate into cardiac fibroblasts under normal and pathologic conditions, and become the predominant fibroblast type in the post-infarction scar. Furthermore, epicardial-derived cardiac fibroblasts are shown to display stromal properties respect to bone marrow-derived cells, critically contributing to the homing and persistence of circulating cells after infarction.
Autores: Pelacho, Beatriz; prosper f;
ISSN 0022-2828  Vol. 62  2013  págs. 43 - 50
The possibility to induce pluripotency in somatic cells or, even further, to induce cell transdifferentiation through the forced expression of reprogramming factors has offered new, attractive options for cardiovascular regenerative medicine. In fact, recent discoveries have demonstrated that induced pluripotent stem (iPS) cells can be differentiated into cardiomyocytes, suggesting that iPS cells have the potential to significantly advance future cardiac regenerative therapies. Herein, we provide an overview of the characteristics and differentiation potential associated with iPS cells. In addition, we discuss current methods for inducing their specification towards a cardiovascular phenotype as well as in vivo evidence supporting the therapeutic benefit of iPS-derived cardiac cells. Finally, we describe recent findings regarding the use of iPS-derived cells for modeling several genetic cardiac disorders, which have indicated that these pluripotent cells represent an ideal tool for drug testing and might contribute to the development of future personalized regenerative cell therapies. (C) 2013 Elsevier Ltd. All rights reserved.
Autores: Simon-Yarza, T; et al.
ISSN 0378-5173  Vol. 440  Nº 1  2013  págs. 13 - 18
The potential of poly(lactic-co-glycolic) acid (PLGA) microparticles as carriers for vascular endothelial growth factor (VEGF) has been demonstrated in a previous study by our group, where we found improved angiogenesis and heart remodeling in a rat myocardial infarction model (Formiga et al., 2010). However, the observed accumulation of macrophages around the injection site suggested that the efficacy of treatment could be reduced due to particle phagocytosis. The aim of the present study was to decrease particle phagocytosis and consequently improve protein delivery using stealth technology. PEGylated microparticles were prepared by the double emulsion solvent evaporation method using TROMS (Total Recirculation One Machine System). Before the uptake studies in monocyte-macrophage cells lines (J774 and Raw 264.7), the characterization of the microparticles developed was carried out in terms of particle size, encapsulation efficiency, protein stability, residual poly(vinyl alcohol) (PVA) and in vitro release. Microparticles of suitable size for intramyocardial injection (5 mu m) were obtained by TROMS by varying the composition of the formulation and TROMS conditions with high encapsulation efficiency (70-90%) and minimal residual PVA content (0.5%). Importantly, the bioactivity of the protein was fully preserved. Moreover, PEGylated microparticles released in phosphate buffer 50% of the entrapped protein within 4 h, reaching a plateau within the first day of the in vitro study. Finally, the use of PLGA microparticles coated with PEG resulted in significantly decreased uptake of the carriers by macrophages, compared with non PEGylated microparticles, as shown by flow cytometry and fluorescence microscopy. On the basis of these results, we concluded that PEGylated microparticles loaded with VEGF could be used for delivering growth factors in the myocardium. (C) 2012 Elsevier B.V. All rights reserved.
Autores: Araña, M; Pena, E.; Abizanda, Gloria María; et al.
ISSN 1742-7061  Vol. 9  Nº 4  2013  págs. 6075 - 6083
The use of scaffolds composed of natural biodegradable matrices represents an attractive strategy to circumvent the lack of cell engraftment, a major limitation of stem cell therapy in cardiovascular diseases. Bovine-derived non-porous collagen scaffolds with different degrees of cross-linking (C0, C2, C5 and C10) were produced and tested for their mechanical behavior, in vitro biocompatibility with adipose-derived stem cells (ADSCs) and tissue adhesion and inflammatory reaction. Uniaxial tensile tests revealed an anisotropic behavior of collagen scaffolds (2 x 0.5 cm) and statistically significant differences in the mechanical behavior between cross-linked and non-cross-linked scaffolds (n = 5). In vitro, ADSCs adhered homogenously and showed a similar degree of proliferation on all four types of scaffolds (cells x 10(3) cm(-2) at day 7: C0: 94.7 +/- 37.1; C2: 91.7 +/- 25.6; C5: 88.2 +/- 6.8; C10: 72.8 +/- 10.7; P = n.s.; n = 3). In order to test the in vivo biocompatibility, a chronic myocardial infarction model was performed in rats and 1.2 x 1.2 cm size collagen scaffolds implanted onto the heart I month post-infarction. Six animals per group were killed 2, 7 and 30 days after transplant. Complete and long-lasting adhesion to the heart was only observed with the non-cross-linked scaffolds with almost total degradation 1 month post-transplantation. After 7 and 30 days post-implantation, the degree of inflammation was significantly lower in the hearts treated with non-cross-linked scaffolds (day 7: C0: 10.2 +/- 2.1%; C2: 163 +/- 2.9%; C5: 15.9 +/- 4.8%; C10: 17.4 +/- 4.1%; P < 0.05 vs. C0; day 30: C0: 1.3 +/- 1.3%; C2: 9.4 +/- 3.0%; C5: 7.0 +/- 2.1%; C10: 9.8 +/- 2.5%; P < 0.01 vs. C0). In view of the results, the non-cross-linked scaffold (C0) was chosen as an ADSC-carrier sheet and tested in vivo. One week post-implantation, 25.3 +/- 7.0% of the cells transplanted were detected in those animals receiving the cell-carrier sheet whereas no cells were found in animals receiving cells alone (n = 3 animals/group). We conclude that the biocompatibility and mechanical properties of the non-cross-linked collagen scaffolds make them a useful cell carrier that greatly favors tissue cell engraftment and may be exploited for cell transplantation in models of cardiac disease. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Autores: Mazo, Manuel María; Araña, M; Pelacho, Beatriz; et al.
ISSN 1687-966X  2012  págs. UNSP 175979
In recent years, the incredible boost in stem cell research has kindled the expectations of both patients and physicians. Mesenchymal progenitors, owing to their availability, ease of manipulation, and therapeutic potential, have become one of the most attractive options for the treatment of a wide range of diseases, from cartilage defects to cardiac disorders. Moreover, their immunomodulatory capacity has opened up their allogenic use, consequently broadening the possibilities for their application. In this review, we will focus on their use in the therapy of myocardial infarction, looking at their characteristics, in vitro and in vivo mechanisms of action, as well as clinical trials.
Autores: Simon-Yarza, T; et al.
ISSN 1838-7640  Vol. 2  Nº 6  2012  págs. 541 - 552
Since the discovery of the Vascular Endothelial Growth Factor (VEGF) and its leading role in the angiogenic process, this has been seen as a promising molecule for promoting neovascularization in the infarcted heart. However, even though several clinical trials were initiated, no therapeutic effects were observed, due in part to the short half life of this factor when administered directly to the tissue. In this context, drug delivery systems appear to offer a promising strategy to overcome limitations in clinical trials of VEGF.The aim of this paper is to review the principal drug delivery systems that have been developed to administer VEGF in cardiovascular disease. Studies published in the last 5 years are reviewed and the main features of these systems are explained. The tissue engineering concept is introduced as a therapeutic alternative that holds promise for the near future.
Autores: Simon-Yarza, T; et al.
ISSN 1382-4147  Vol. 17  Nº 3  2012  págs. 449 - 473
Cardiovascular diseases remain the first cause of morbidity and mortality in the developed countries and are a major problem not only in the western nations but also in developing countries. Current standard approaches for treating patients with ischemic heart disease include angioplasty or bypass surgery. However, a large number of patients cannot be treated using these procedures. Novel curative approaches under investigation include gene, cell, and protein therapy. This review focuses on potential growth factors for cardiac repair. The role of these growth factors in the angiogenic process and the therapeutic implications are reviewed. Issues including aspects of growth factor delivery are presented in relation to protein stability, dosage, routes, and safety matters. Finally, different approaches for controlled growth factor delivery are discussed as novel protein delivery platforms for cardiac regeneration.
Autores: Corbacho, D.; Pelacho, Beatriz; Albiasu, E.; et al.
Revista: PLOS ONE
ISSN 1932-6203  Vol. 7  Nº 7  2012  págs. e41691
Background: The aim of this article is to present an optimized acquisition and analysis protocol for the echocardiographic evaluation of left ventricle (LV) remodeling in a mouse model of myocardial infarction (MI). Methodology: 13 female DBA/2J mice underwent permanent occlusion of the left anterior descending (LAD) coronary artery leading to MI. Mice echocardiography was performed using a Vevo 770 (Visualsonics, Canada) before infarction, and 7, 14, 30, 60, 90 and 120 days after LAD ligation. LV systolic function was evaluated using different parameters, including the fractional area change (FAC%) computed in four high-temporal resolution B-mode short axis images taken at different ventricular levels, and in one parasternal long axis. Pulsed wave and tissue Doppler modes were used to evaluate the diastolic function and Tei Index for global cardiac function. The echocardiographic measurements of infarct size were validated histologically using collagen deposition labeled by Sirius red staining. All data was analyzed using Shapiro-Wilk and Student's t-tests. Principal Findings: Our results reveal LV dilation resulting in marked remodeling an severe systolic dysfunction, starting seven days after MI (LV internal apical diameter, basal = 2.82 +/- 0.24, 7d = 3.49 +/- 0.42; p < 0.001. End-diastolic area, basal = 18.98 +/- 1.81, 7d = 22.04 +/- 2.11; p < 0.001). A strong statistically significant negative correlation exists between the infarct size and long-axis FAC% (r = -0.946; R-2 = 0.90; p < 0.05). Moreover, the measured Tei Index values confirmed significant post-infarction impairment of the global cardiac function (basal = 0.46 +/- 0.07, 7d = 0.55 +/- 0.08, 14 d = 0.57 +/- 0.06, 30 d = 0.54 +/- 0.06, 60 d = 0.54 +/- 0.07, 90 d = 0.57 +/- 0.08; p < 0.01). Conclusions/Significance: In summary, we have performed a complete characterization of LV post-infarction remodeling in a DBA/2J mouse model of MI, using parameters adapted to the particular characteristics of the model In the future, this well characterized model will be used in both investigative and pharmacological studies that require accurate quantitative monitoring of cardiac recovery after myocardial infarction.
Autores: Mazo, Manuel María; Gavira, Juan José; Abizanda, Gloria María; et al.
ISSN 0963-6897  Vol. 21  Nº 5  2012  págs. 1023 - 1037
Fresh adipose-derived cells have been shown to be effective in the treatment of acute myocardial infarction (MI), but their role in the chronic setting is unknown. We sought to determine the long-term effect of the adipose derived-stromal vascular fraction (SVF) cell transplantation in a rat model of chronic MI. MI was induced in 82 rats by permanent coronary artery ligation and 5 weeks later rats were allocated to receive an intramyocardial injection of 10(7) GFP-expressing fresh SVF cells or culture media as control. Heart function and tissue metabolism were determined by echocardiography and F-18-FDG-microPET, respectively, and histological studies were performed for up to 3 months after transplantation. SVF induced a statistically significant long-lasting (3 months) improvement in cardiac function and tissue metabolism that was associated with increased revascularization and positive heart remodeling, with a significantly smaller infarct size, thicker infarct wall, lower scar fibrosis, and lower cardiac hypertrophy. Importantly, injected cells engrafted and were detected in the treated hearts for at least 3 months, directly contributing to the vasculature and myofibroblasts and at negligible levels to cardiomyocytes. Furthermore, SVF release of angiogenic (VEGF and HGF) and proinflammatory (MCP-1) cytokines, as well as TIMP1 and TIMP4, was demonstrated in vitro and in vivo, strongly suggesting that they have a trophic effect. These results show the potential of SVF to contribute to the regeneration of ischemic tissue and to provide a long-term functional benefit in a rat model of chronic MI, by both direct and indirect mechanisms.
Autores: López, Xabier; Pelacho, Beatriz; Peñuelas, Iván; et al.
ISSN 0963-6897  Vol. 20  Nº 2  2011  págs. 259 - 269
There is a need for comparative studies to determine which cell types are better candidates to remedy ischemia. Here, we compared human AC133(+) cells and multipotent adult progenitor cells (hMAPC) in a mouse model reminiscent of critical limb ischemia. hMAPC or hAC133(+) cell transplantation induced a significant improvement in tissue perfusion (measured by microPET) 15 days posttransplantation compared to controls. This improvement persisted for 30 days in hMAPC-treated but not in hAC133(+)-injected animals. While transplantation of hAC133(+) cells promoted capillary growth, hMAPC transplantation also induced collateral expansion, decreased muscle necrosis/fibrosis, and improved muscle regeneration. Incorporation of differentiated MC 133(+) or hMAPC progeny into new vessels was limited; however, a paracrine angio/arteriogenic effect was demonstrated in animals treated with hMAPC. Accordingly, hMAPC-conditioned, but not hAC133(+)-conditioned, media stimulated vascular cell proliferation and prevented myoblast, endothelial, and smooth muscle cell apoptosis in vitro. Our study suggests that although hAC133(+) cell and hMAPC transplantation both contribute to vascular regeneration in ischemic limbs, hMAPC exert a more robust effect through trophic mechanisms, which translated into collateral and muscle fiber regeneration. This, in turn, conferred tissue protection and regeneration with longer term functional improvement.
Autores: Pelacho, Beatriz; Mazo, Manuel María; Gavira, Juan José; et al.
ISSN 1937-5387  Vol. 4  Nº 2  2011  págs. 154 - 160
Cardiovascular diseases constitute the first cause of mortality and morbidity worldwide. Alternative treatments like transplantation of (stem) cell populations derived from several adult tissue sources, like the bone marrow, skeletal muscle, or even adipose tissue, have been already employed in diverse clinical trials. Results from these studies and previous animal studies have reached to the conclusion that stem cells induce a benefit in the treated hearts, which is exerted mainly through paracrine mechanisms and not through direct differentiation as it was initially expected. However, a strong technical limitation for the stem cell therapy, which is the low level of cell survival and engraftment, diminishes their potential. Thus, new strategies like combination of the cells with bioengineering techniques have been developed and are being subject of intense research, suggesting that new strategies may improve the efficacy of these therapies. In this review, we will discuss the different therapeutic approaches, drawbacks, and future expectations of new regenerative therapies for cardiovascular diseases.
Autores: Mazo, Manuel María; Gavira, Juan José; Pelacho, Beatriz; et al.
ISSN 1937-5387  Vol. 4  Nº 2  2011  págs. 145 - 153
In recent years, stem cell treatment of myocardial infarction has elicited great enthusiasm upon scientists and physicians alike, thus making the finding of a suitable cell a compulsory subject for modern medicine. Due to its potential, accessibility and efficiency of harvesting, adipose tissue has become one of the most attractive sources of stem cells for regenerative therapies. The differentiation capacity and the paracrine activity of these cells has made them an optimal candidate for the treatment of a diverse range of diseases from immunological disorders as graft versus host disease to cardiovascular pathologies like peripheral ischemia. In this review, we will focus on the use of stem cells derived from adipose tissue for treatment of myocardial infarction, with special attention to their putative in vivo mechanisms of action.
Autores: Mazo, Manuel María; Pelacho, Beatriz; prosper f;
ISSN 1937-5387  Vol. 3  Nº 2  2010  págs. 79 - 88
Although recent advances for the treatment of myocardial infarction have dramatically increased the rate of survival after the ischemic event, this has also led to a rise in the number of chronic patients, making the finding of a suitable therapy a compulsory subject for modern medicine. Over the last decade, stem cells have been a promise for the cure of several diseases not only due to their plasticity but also to their capacity to act in a paracrine manner and influence the affected tissue, prompting the launching of several clinical trials. In spite of the knowledge already acquired, stem cell application to chronically infarcted hearts has been much less approached than its acute counterpart. Through this review, we will focus in stem cell therapy in animal models of chronic myocardial infarction: cell types employed, functional results, mechanisms analyzed, and questions raised.
Autores: Lu, T.; Pelacho, Beatriz; Hao, H.; et al.
ISSN 1937-3341  Vol. 16  Nº 10  2010  págs. 3111 - 3117
This study was to determine if bone marrow multipotent adult progenitor cells (MAPCs) underwent cardiac specification and Oct-4 expression during their cardiomyocyte differentiation in vitro. MAPCs were isolated from rat bone marrow, treated with 5-azacytidine (5-aza, 1 mu M) for 24 h, and cultured in a serum-free medium for cardiac differentiation for up to 35 days. The cells started to express early cardiac-specific genes Nkx2.5 and GATA-4 with a significant increase in their mRNA level within 24 h after 5-aza treatment. Western blotting analysis and immunofluorescence staining revealed that the cardiac-specific proteins connexin-43 and troponin I were expressed in the cells 7 days after 5-aza treatment. Flow cytometry analysis demonstrated that over 37% of the cells were positive for troponin I by 35 days of differentiation, although the cells did not display spontaneous contraction. On the other hand, the undifferentiated MAPCs expressed a significant level of the stem-cell-specific marker Oct-4 that was dramatically decreased in the cells shortly after the initiation of cardiomyocyte differentiation as evaluated using real-time (RT)-polymerase chain reaction, Western blotting, immunofluorescence staining, and flow cytometry. These data indicated that MAPCs were able to effectively differentiate into cardiomyocyte-like cells after 5-aza induction in association with downregulation of Oct-4 expression.
Autores: Gavira, Juan José; Abizanda, Gloria María; et al.
ISSN 0195-668X  Vol. 31  Nº 8  2010  págs. 1013 - 1021
Aims Although transplantation of skeletal myoblast (SkM) in models of chronic myocardial infarction (MI) induces an improvement in cardiac function, the limited engraftment remains a major limitation. We analyse in a pre-clinical model whether the sequential transplantation of autologous SkM by percutaneous delivery was associated with increased cell engraftment and functional benefit. Methods and results Chronically infarcted Goettingen minipigs (n = 20) were divided in four groups that received either media control or one, two, or three doses of SkM (mean of 329.6 x 10(6) cells per dose) at intervals of 6 weeks and were followed for a total of 7 months. At the time of sacrifice, cardiac function was significantly better in animals treated with SkM in comparison with the control group. A significantly greater increase in the Delta LVEF was detected in animals that received three doses vs. a single dose of SkM. A correlation between the total number of transplanted cells and the improvement in LVEF and Delta LVEF was found (P < 0.05). Skeletal myoblast transplant was associated with an increase in tissue vasculogenesis and decreased fibrosis (collagen vascular fraction) and these effects were greater in animals receiving three doses of cells. Conclusion Repeated injection of SkM in a model of chronic MI is feasible and safe and induces a significant improvement in cardiac function.
Autores: Mazo, Manuel María; Gavira, Juan José; Abizanda, Gloria María; et al.
ISSN 0963-6897  Vol. 19  Nº 3  2010  págs. 313 - 328
The aim of this study is to assess the long-term effect of mesenchymal stem cells (MSC) transplantation in a rat model of chronic myocardial infarction (MI) in comparison with the effect of bone marrow mononuclear cells (BM-MNC) transplant. Five weeks after induction of MI, rats were allocated to receive intramyocardial injection of 10(6) GFP-expressing cells (BM-MNC or MSC) or medium as control. Heart function (echocardiography and (18)F-FDG-microPET) and histological studies were performed 3 months after transplantation and cell fate was analyzed along the experiment (1 and 2 weeks and 1 and 3 months). The main findings of this study were that both BM-derived populations, BM-MNC and MSC, induced a long-lasting (3 months) improvement in LVEF (BM-MNC: 26.61 +/- 2.01% to 46.61 +/- 3.7%, p <0.05; MSC: 27.5 +/- 1.28% to 38.8 +/- 3.2%, p < 0.05) but remarkably, only MSC improved tissue metabolism quantified by (18)F-FDG uptake (71.15 +/- 1.27 to 76.31 +/- 1.11, p<0.01), which was thereby associated with a smaller infarct size and scar collagen content and also with a higher revascularization degree. Altogether, results show that MSC provides a long-term superior benefit than whole BM-MNC transplantation in a rat model of chronic MI.
Autores: Pelacho, Beatriz; Garbayo, Elisa; et al.
ISSN 0168-3659  Vol. 147  Nº 1  2010  págs. 30 - 37
The use of pro-angiogenic growth factors in ischemia models has been associated with limited success in the clinical setting, in part owing to the short lived effect of the injected cytokine. The use of a microparticle system could allow localized and sustained cytokine release and consequently a prolonged biological effect with induction of tissue revascularization. To assess the potential of VEGF(165) administered as continuous release in ischemic disease, we compared the effect of delivery of poly(lactic-co-glycolic acid) (PLGA) microparticles (MP) loaded with VEGF(165) with free-VEGF or control empty microparticles in a rat model of ischemia-reperfusion. VEGF165 loaded microparticles could be detected in the myocardium of the infarcted animals for more than a month after transplant and provided sustained delivery of active protein in vitro and in vivo. One month after treatment, an increase in angiogenesis (small caliber caveolin-1 positive vessels) and arteriogenesis (alpha-SMA-positive vessels) was observed in animals treated with VEGF microparticles (p < 0.05), but not in the empty microparticles or free-VEGF groups. Correlating with this data, a positive remodeling of the heart was also detected in the VEGF-microparticle group with a significantly greater LV wall thickness (p < 0.01). In conclusion, PICA microparticle is a feasible and promising cytokine delivery system for treatment of myocardial ischemia. This strategy could be scaled up and explored in pre-clinical and clinical studies. (C) 2010 Elsevier B.V. All rights reserved.
Autores: Pelacho, Beatriz; Pérez, Ana Isabel; prosper f;
Libro:  Platelet rich plasma in orthopaedics and sports medicine
2018  págs. 83 - 97
Autores: Carvajal-Vergara, Xonia; Rodriguez-Madoz, Juan Roberto; Pelacho, Beatriz; et al.
Libro:  Cell therapy: current status and future directions
2017  págs. 173 - 196
The field of regenerative medicine has made great progress with the development of cell reprogramming and gene editing techniques. The option to derive pluripotent cells from somatic cells by overexpression of pluripotent factors or specific molecules, and even more the possibility to reprogram one somatic cell type to another somatic cell type in vitro and in vivo, has offered many new options for future therapies. In this chapter, we provide an overview of the studies performed to understand the mechanisms and to develop the techniques for cell reprogramming, focusing specially in their application in cardiac regeneration and rare disease modeling. First, we discuss the plasticity of cells and methods for their reprogramming. Also, a description of the different studies for differentiation of pluripotent cells toward cardiovascular cells and direct cell reprogramming is provided. Finally, the use of reprogrammed cells as a model for human pathologies, mainly rare diseases, the different aspects that should be bear in mind for optimal model development, the use of gene editing for creating novel and improved disease models, and the therapeutic applications of iPSC-based models have been thoroughly described in this chapter.
Autores: Pelacho, Beatriz; prosper f;
Libro:  Biología celular biomédica
2015  págs. 397
Autores: Mazo, Manuel María; Araña, M; Pelacho, Beatriz; et al.
Libro:  Adult and pluripotent stem cells
2014  págs. 1-19
In recent years, the incredible boost in stem cell research has kindled the expectations of both patients and physicians. Mesenchymal progenitors, owing to their availability, ease of manipulation and therapeutic potential, have become one of the most attractive options for the treatment of a wide range of diseases, from cartilage defects to cardiac disorders. Moreover, their immunomodulatory capacity has opened up their allogenic use, consequently broadening the possibilities for their application. In this review, we will focus on their use in the therapy of animal preclinical models of myocardial infarction, with special focus on their characteristics and their in vitro and in vivo mechanisms of action.
Autores: Pelacho, Beatriz; prosper f;
Libro:  Técnicas en histología y biología celular
2014  págs. 303 - 327
Autores: Pelacho, Beatriz; Mazo, Manuel María; et al.
Libro:  Regenerative medicine and cell therapy
Vol. 316  2013  págs. 65 - 112
Autores: Araña, M; Mazo, Manuel María; Aranda, Pablo; et al.
Libro:  Cellular cardiomyoplasty: methods and protocols, methods in molecular biology
Vol. 1036  2013  págs. 47 - 61
Over the last decade, cell therapy has emerged as a potentially new approach for the treatment of cardiovascular diseases. Among the wide range of cell types and sources, adipose-derived mesenchymal stem cells have shown promise, mainly due to its plasticity and remarkable paracrine-secretion capacity, largely demonstrated at the in vitro and in vivo levels. Furthermore, its accessibility and abundance, the low morbidity of the surgical procedure, its easy isolation, culture, and long-term passaging capacity added to its immunomodulatory properties that could allow its allogeneic transplantation, making it one of the most attractive candidates for clinical application. In this chapter, we will focus on the methodology for the isolation, expansion, phenotypical characterization, differentiation, and storage of the adipose-derived stem cells.
Autores: Araña, M; Mazo, Manuel María; Aranda, Pablo; et al.
Libro:  Cellular cardiomyoplasty: methods and protocols
Vol. 1036  2013  págs. 47 - 61