Figure 1 - available via license: CC BY-NC-ND
Content may be subject to copyright.
Morphology and multipotency of adipose-derived mesenchymal stem cells (ASCs). (A): Representative phase-contrast photomicrograph of ASCs adhered to tissue-culture polystyrene (N = 3), obtained with an objective magnification of ×4. (B): Oil Red O staining of ASCs cultured in adipogenic differentiation medium for 14 days (N = 3). Red staining is indicative of triglycerides and lipids. (C): von Kossa staining of ASCs cultured in osteogenic differentiation medium for 28 days (N = 3). Brown staining is indicative of mineralization. (D): Alcian Blue staining of ASCs cultured in chondrogenic differentiation medium for 28 days (N = 3). Blue staining is indicative of proteoglycans. (B-D): Positive staining was not observed in unstimulated ASC controls (data not shown). Representative photomicrographs were taken by bright-field light microscopy using an objective magnification of ×4.

Morphology and multipotency of adipose-derived mesenchymal stem cells (ASCs). (A): Representative phase-contrast photomicrograph of ASCs adhered to tissue-culture polystyrene (N = 3), obtained with an objective magnification of ×4. (B): Oil Red O staining of ASCs cultured in adipogenic differentiation medium for 14 days (N = 3). Red staining is indicative of triglycerides and lipids. (C): von Kossa staining of ASCs cultured in osteogenic differentiation medium for 28 days (N = 3). Brown staining is indicative of mineralization. (D): Alcian Blue staining of ASCs cultured in chondrogenic differentiation medium for 28 days (N = 3). Blue staining is indicative of proteoglycans. (B-D): Positive staining was not observed in unstimulated ASC controls (data not shown). Representative photomicrographs were taken by bright-field light microscopy using an objective magnification of ×4.

Source publication
Article
Full-text available
Considerable effort has been directed toward deriving endothelial cells (ECs) from adipose-derived mesenchymal stem cells (ASCs) since 2004, when it was first suggested that ECs and adipocytes share a common progenitor. While the capacity of ASCs to express endothelial markers has been repeatedly demonstrated, none constitute conclusive evidence of...

Contexts in source publication

Context 1
... the stromal vascular fraction of CD45 + leukocytes and CD31 + ECs to prevent their contamination of ASC cultures from confounding subse- quent evaluations of the endothelial plasticity of ASCs [8,9]. ASCs were defined as the TCPS-adherent CD45 − CD31 − stromal vascular cells [8,9]. They exhibited a spindle-shaped fibroblast-like mor- phology ( Fig. 1A; N = 3) and were capable of clonal expansion (33.1 AE 3.5% CFU-F; N = 3). They were negative for the pan- hematopoietic marker CD45 (0.4 AE 0.3%) and endothelial marker CD31 (0.1 AE 0.0%), and expressed characteristic stromal markers CD13 (99.8 AE 0.1%), CD44 (99.9 AE 0.1%), CD105 (88.9 AE 4.3%), CD29 (96.7 AE 5.5%), CD90 (97.2 AE ...
Context 2
... (33.1 AE 3.5% CFU-F; N = 3). They were negative for the pan- hematopoietic marker CD45 (0.4 AE 0.3%) and endothelial marker CD31 (0.1 AE 0.0%), and expressed characteristic stromal markers CD13 (99.8 AE 0.1%), CD44 (99.9 AE 0.1%), CD105 (88.9 AE 4.3%), CD29 (96.7 AE 5.5%), CD90 (97.2 AE 4.8%), and CD73 (99.9 AE 0.1%; Supporting Information Fig. S1; N = 3) [19]. The multipotency of the ASCs was demonstrated by their differentiation along the adi- pogenic (Fig. 1B), osteogenic (Fig. 1C), and chondrogenic ( Fig. 1D) lineages (N = 3) ...
Context 3
... marker CD31 (0.1 AE 0.0%), and expressed characteristic stromal markers CD13 (99.8 AE 0.1%), CD44 (99.9 AE 0.1%), CD105 (88.9 AE 4.3%), CD29 (96.7 AE 5.5%), CD90 (97.2 AE 4.8%), and CD73 (99.9 AE 0.1%; Supporting Information Fig. S1; N = 3) [19]. The multipotency of the ASCs was demonstrated by their differentiation along the adi- pogenic (Fig. 1B), osteogenic (Fig. 1C), and chondrogenic ( Fig. 1D) lineages (N = 3) ...
Context 4
... AE 0.0%), and expressed characteristic stromal markers CD13 (99.8 AE 0.1%), CD44 (99.9 AE 0.1%), CD105 (88.9 AE 4.3%), CD29 (96.7 AE 5.5%), CD90 (97.2 AE 4.8%), and CD73 (99.9 AE 0.1%; Supporting Information Fig. S1; N = 3) [19]. The multipotency of the ASCs was demonstrated by their differentiation along the adi- pogenic (Fig. 1B), osteogenic (Fig. 1C), and chondrogenic ( Fig. 1D) lineages (N = 3) ...
Context 5
... stromal markers CD13 (99.8 AE 0.1%), CD44 (99.9 AE 0.1%), CD105 (88.9 AE 4.3%), CD29 (96.7 AE 5.5%), CD90 (97.2 AE 4.8%), and CD73 (99.9 AE 0.1%; Supporting Information Fig. S1; N = 3) [19]. The multipotency of the ASCs was demonstrated by their differentiation along the adi- pogenic (Fig. 1B), osteogenic (Fig. 1C), and chondrogenic ( Fig. 1D) lineages (N = 3) ...

Citations

... The use of adipose tissue may be of particular interest as both fibroblast-like human adipose-derived stem cells (ASCs) and human adipose-derived microvascular endothelial cells (HAMVECs) can be obtained from a single tissue sample [143]. ASCs are a heterogeneous group of fibroblast-like cells [144], which are phenotypically indistinguishable from fibroblasts [145]. Only 5% of genes are uniquely expressed between HGFs and human dermal fibroblasts, with their fundamental characteristics being the same [146]. ...
Article
Full-text available
There is a shortage of suitable tissue-engineered solutions for gingival recession, a soft tissue defect of the oral cavity. Autologous tissue grafts lead to an increase in morbidity due to complications at the donor site. Although material substitutes are available on the market, their development is early, and work to produce more functional material substitutes is underway. The latter materials along with newly conceived tissue-engineered substitutes must maintain volumetric form over time and have advantageous mechanical and biological characteristics facilitating the regeneration of functional gingival tissue. This review conveys a comprehensive and timely perspective to provide insight towards future work in the field, by linking the structure (specifically multilayered systems) and function of electrospun material-based approaches for gingival tissue engineering and regeneration. Electrospun material composites are reviewed alongside existing commercial material substitutes’, looking at current advantages and disadvantages. The importance of implementing physiologically relevant degradation profiles and mechanical properties into the design of material substitutes is presented and discussed. Further, given that the broader tissue engineering field has moved towards the use of pre-seeded scaffolds, a review of promising cell options, for generating tissue-engineered autologous gingival grafts from electrospun scaffolds is presented and their potential utility and limitations are discussed.
... ± 5.0%, respectively; p = 0.0019; Fig. 1d), and they exhibited a comparable morphology to the contaminating cells (Fig. 1e). Notably, these CD45 − CD31 − stromal vascular cells comprised adipose tissuederived stromal/stem cells (ASCs) 29 , having been previously validated to meet the phenotypic criteria delineated by the International Federation for Adipose Therapeutics and Science and the International Society for Cellular Therapy 30 . ...
... The phenotypic heterogeneity of the endothelium and the paucity of markers with specificity and sensitivity for the endothelial lineage presents a challenge to the assessment of an endothelial phenotype 1 . It has previously misled many to mistake monocytes for endothelial progenitor cells 31 , platelets for circulating ECs 32 , omental mesothelial cells for HAMVECs 33,34 , and even ASCs for EC substitutes 29 . Accordingly, comprehensive phenotypic comparisons to representative EC controls were performed to confirm the endothelial phenotype of the putative HAMVECs. ...
... Furthermore, their uptake of acetylated lowdensity lipoprotein (AcLDL) was similar (Fig. 2d). Importantly, these morphological, molecular, and functional endothelial hallmarks exhibited by HAMVECs were previously shown to be negligible in ASCs when cultured under identical conditions and compared with the same EC controls 29 . Lastly, HAMVECs exhibited an angiogenic capacity comparable to that of the EC Fig. 1 Primary cultures of human adipose tissue-derived microvascular endothelial cells (HAMVECs) are often overgrown by residual adipose tissuederived stromal/stem cells (ASCs) from the magnet-assisted cell sorting (MACS) procedure. ...
Article
Full-text available
Endothelial cells are among the fundamental building blocks for vascular tissue engineering. However, a clinically viable source of endothelium has continued to elude the field. Here, we demonstrate the feasibility of sourcing autologous endothelium from human fat – an abundant and uniquely dispensable tissue that can be readily harvested with minimally invasive procedures. We investigate the challenges underlying the overgrowth of human adipose tissue-derived microvascular endothelial cells by stromal cells to facilitate the development of a reliable method for their acquisition. Magnet-assisted cell sorting strategies are established to mitigate the non-specific uptake of immunomagnetic microparticles, enabling the enrichment of endothelial cells to purities that prevent their overgrowth by stromal cells. This work delineates a reliable method for acquiring human adipose tissue-derived microvascular endothelial cells in large quantities with high purities that can be readily applied in future vascular tissue engineering applications.
... In fact, the lack of vascularization has proved to be a significant challenge in BTE (Rouwkema et al., 2008;Rouwkema & Khademhosseini, 2016). The major problem is that nutrients and oxygen are able to diffuse at most to only at a maximum of 2 mm distance, meaning that cells implanted in larger constructs are left to die after implantation (Antonyshyn et al., 2019;Volz et al., 2016). Moreover, angiogenesis of vessels growing into the construct in the defect site is too slow to keep the implanted cells viable. ...
... Khan et al., 2017;Kukumberg et al., 2017;Marino et al., 2012) and their combination have been used in the endothelial differentiation of MSCs in vitro. The most used commercial medium in endothelial differentiation is Endothelial Growth Medium-2 (EGM-2) from Lonza originally meant for the culture of mature ECs (Antonyshyn et al., 2019;Correia et al., 2014), which consist growth factors epidermal growth factor (EGF), VEGF and R 3 insulinlike growth factor-1 (R 3 -IGF-1) as well as hydrocortisone, ascorbic acid and heparin with 2 % FBS and antibiotics. In addition to supplements added into the medium, also shear stress have been shown to guide BMSCs towards an endothelial lineage (M. ...
... They compared the EGM-2 differentiated hASCs to ECs derived from umbilical vein, coronary artery and dermal microvasculature, and concluded that even though endothelial protein and gene marker levels were up-regulated in hASCs, the levels were still significantly lower in contrast to the ECs (Antonyshyn et al., 2019). Most of the endothelial differentiation studies using human cells are conducted in FBS based media (Antonyshyn et al., 2019;S. Khan et al., 2017;Kukumberg et al., 2017;Correia et al., 2014). ...
Thesis
Full-text available
http://urn.fi/URN:ISBN:978-952-03-1414-9 Bone tissue is the second most common tissue transplant after blood transfusion and as people age, the need for bone transplants is expected to rise even more. Despite the great efforts in biomaterial research and development, autologous bone remains the benchmark among bone grafts whereas synthetic bone grafts are still less-used. Effective and reliable development of synthetic bone grafts require efficient cellular assessments in vitro including the evaluation of osteogenic as well as vasculogenic potential of the scaffolds. Adult stem cells, including human adipose stem cells (hASCs) and human bone marrow stem cells (hBMSCs), provide an excellent tool for this as they have been shown to differentiate to bone-forming cells and endothelial cells. However, efficient and cost-effective approaches to induce osteogenic and endothelial differentiation are still needed. This thesis focuses on the study and development of in vitro differentiation strategies for hASCs and hBMSCs in 3-dimensional (3D) culture in order to study and verify the feasibility of novel bone substitute materials. Firstly, two clinically used synthetic bone graft scaffolds, BoneCeramic composed of biphasic calcium phosphate and BioRestore composed of bioactive glass (BaG), were compared in hASC culture and, the effectiveness of commonly used growth factors bone morphogenetic protein (BMP)-2, BMP-7 and vascular endothelial growth factor (VEGF) on hASC osteogenesis were compared to OM. As ceramics are hard and brittle making them difficult to implant and undesirable to load-bearing sites, an elastic β-tricalciumphosphate/poly(L-lactide-co-ε-caprolactone) (βTCP/PLCL) composite was developed using supercritical CO2 (scCO2) foaming. The capacity of the composites to support hASC osteogenesis and vasculogenesis were studied in vitro in hASC culture and in vivo in rabbit femur defect. Finally, 3D printed polycaprolactone (PCL)/copper-doped BaG composites were developed and their osteogenic and vasculogenic potential was studied in vitro in hBMSC culture and in a co-culture of hBMSCs and human umbilical vein endothelial cells (HUVECs). The two biomaterial scaffolds BoneCeramic and BioRestore demonstrated differential effects on hASCs: BoneCeramic induced ALP activity and collagen production of hASCs, while BioRestore stimulated hASC proliferation. In comparison to the growth factors, OM was more effective in the osteogenic differentiation of hASCs in vitro in BoneCeramic and BioRestore. On the other hand, combining the growth factors with OM did not sensitize hASCs to the growth factors. The β-TCP/PLCL composites supported the viability, proliferation and osteogenic differentiation of hASCs reliably in vitro. When studying the osteogenic and endothelial differentiation of hASCs in β-TCP/PLCL composites, hASCs differentiated towards both lineages when cultured in endothelial medium (EM) although the differentiation was left in a premature state. Culture in a cocktail medium of OM and EM supported osteogenic but not endothelial differentiation of hASCs. The in vivo study confirmed biocompatibility as well as osteoconductivity of the composite as no inflammation, fibrous tissue or cyst formation was detected and, native bone tissue was able to grow on and in the β-TCP/PLCL composite already at 4 weeks. In the evaluation of 3D printed PCL/BaG-Cu composites, copper was observed to have a dose-dependent cytotoxic effect on hBMSCs in vitro. The PCL/BaG composite induced hBMSC osteogenesis while the addition of copper in BaG had an inhibiting effect on the osteogenic differentiation of hBMSCs. In co-culture of hBMSCs and HUVECs, both PCL/BaG and PCL/BaG-Cu scaffolds supported tubule formation, but the added copper did not boost the vasculogenic effect of the composite. In conclusion, OM was shown to be a cost-effective osteogenic stimulant in 3D culture as compared to exogenously added growth factors. The feasibility of the scCO2 foamed β-TCP/PLCL composite as potential a bone graft for clinical use was evidenced in vitro and in vivo. The 3D printed PCL/BaG composite showed promise in supporting osteogenesis in vitro whereas the addition of copper hindered the osteogenic effect of the composite. Both PCL/BaG and PCL/BaG-Cu composites supported tubule formation in hBMSC+HUVEC co-culture but the copper did not induce the vasculogenic effect of the composite. To conclude, the elastic and bioactive synthetic polymer -based composites consisting osteoconductive ceramics are highly promising alternatives for synthetic bone grafts when compared to hard ceramics.
... For instance, whether ADSCs can differentiate into ECs and be directly involved in neovascularization or ADSC transplantation is just cell-based cytokine therapy for ischemic disease is still controversial. 20,[22][23][24][25] In addition, although ADSCs have shown efficacy in regenerative and reconstructive medicine, SVF was considered to have superiority compared with ADSC treatment alone. 26 In a study of a rat cavernous nerve injury model, the SVF treatment group showed statistically better results, with a higher smooth muscle/collagen ratio and more EC content compared with the ADSC group. ...
... 24,[67][68][69][70] However, some other studies were unable to prove the differentiation capacity of ADSCs toward an endothelial lineage. 22, 25 Antonyshyn et al 25 reported that ADSCs without CD45+ leukocytes and CD31+ ECs have limited endothelial differentiation by well-established biochemical stimuli. Although ADSCs are isolated from SVF, they are definitely not a homogeneous population. ...
... 24,[67][68][69][70] However, some other studies were unable to prove the differentiation capacity of ADSCs toward an endothelial lineage. 22, 25 Antonyshyn et al 25 reported that ADSCs without CD45+ leukocytes and CD31+ ECs have limited endothelial differentiation by well-established biochemical stimuli. Although ADSCs are isolated from SVF, they are definitely not a homogeneous population. ...
Article
Adult stem cell–based therapy has been regarded as a promising treatment for tissue ischemia because of its ability to promote new blood vessel formation. Bone marrow–derived mesenchymal stem cells are the most used angiogenic cells for therapeutic neovascularization, yet the side effects and low efficacy have limited their clinical application. Adipose stromal vascular fraction is an easily accessible, heterogeneous cell system comprised of endothelial, stromal, and hematopoietic cell lineages, which has been shown to spontaneously form robust, patent, and functional vasculatures in vivo. However, the characteristics of each cell population and their specific roles in neovascularization remain an area of ongoing investigation. In this review, we summarize the functional capabilities of various stromal vascular fraction constituents during the process of neovascularization and attempt to analyze whether the cross-talk between these constituents generates a synergetic effect, thus contributing to the development of new potential therapeutic strategies to promote neovascularization.
Article
Human adipose tissue-resident microvascular endothelial cells are not only garnering attention for their emergent role in the pathogenesis of obesity-related metabolic disorders, but are also of considerable interest for vascular tissue engineering due, in part, to the abundant, accessible, and uniquely dispensable nature of the tissue. Here, we delineate a protocol for the acquisition of microvascular endothelial cells from human fat. A cheaper, smaller, and simpler alternative to fluorescence-assisted cell sorting for the immunoselection of cells, our protocol adapts magnet-assisted cell sorting for the isolation of endothelial cells from enzymatically digested adipose tissue and the subsequent enrichment of their primary cultures. Strategies are employed to mitigate the non-specific uptake of immunomagnetic microparticles, enabling the reproducible acquisition of human adipose tissue-resident microvascular endothelial cells with purities ≥98%. They exhibit morphological, molecular, and functional hallmarks of endothelium, yet retain a unique proteomic signature when compared with endothelial cells derived from different vascular beds. Their cultures can be expanded for >10 population doublings and can be maintained at confluence for at least 28 days without being overgrown by residual stromal cells from the cell sorting procedure. The isolation of human adipose tissue-resident microvascular endothelial cells can be completed within 6 hours and their enrichment within 2 hours, following approximately 7 days in culture. Graphical abstract.
Article
Adipose tissue is an abundant, accessible, and uniquely dispensable source of cells for vascular tissue engineering. Despite its intrinsic endothelial cells, considerable effort is directed at deriving endothelium from its resident stem and progenitor cells. Here, we investigate the composition of human adipose tissue and characterize the phenotypes of its constituent cells in order to help ascertain their potential utility for vascular tissue engineering. Unsupervised clustering based on cell-surface protein signatures failed to detect CD45–CD31–VEGFR2⁺ endothelial progenitor cells within adipose tissue, but supported further investigation of its resident CD45–CD31⁺ microvascular endothelial cells (HAMVECs) and CD45–CD31– stromal/stem cells (ASCs). The endothelial differentiation of ASCs altered their proteome, but it remained distinct from that of primary endothelial cell controls – as well as HAMVECs – regardless of their arterial-venous specification or macrovascular-microvascular origin. Rather, ASCs retained a proteome indicative of a perivascular phenotype, which was supported by their ability to facilitate the capillary morphogenesis of HAMVECs. This study supports the use of HAMVECs for the generation of endothelium. It suggests that the utility of ASCs for vascular tissue engineering lies in their capacity to remodel the extracellular matrix and to function as mural cells.
Article
The capacity of mesenchymal stromal cells to promote vascular regeneration in vivo can be enhanced by the combination of specific small-molecule inhibitors and the right waveform of mechanical stretch.
Article
Tissue engineering has garnered significant attention for its potential to address the predominant modes of failure of small diameter vascular prostheses, namely mid-graft thrombosis and anastomotic intimal hyperplasia. In this review, we describe two main features underpinning the promise of tissue-engineered vascular grafts: the incorporation of an anti-thrombogenic endothelium, and the generation of a structurally and biomechanically mimetic extracellular matrix. From the early attempts at the in-vitro endothelialization of vascular prostheses in the 1970s through to the ongoing clinical trials of fully tissue-engineered vascular grafts, the historical advancements and unresolved challenges that characterize the current state-of-the-art are summarized in a manner that establishes a guide for the development of an effective vascular prosthesis for small diameter arterial reconstruction. The importance of endothelial cell purity and their arterial specification for the prevention of both diffuse neo-intimal hyperplasia and the accelerated development of atherosclerotic lesions is delineated. Additionally, the need for an extracellular matrix that recapitulates both the composition and structure of native elastic arteries to facilitate the protracted stability and patency of an engineered vaso-active conduit is described. Finally, the capacity of alternative sources of cells and mechanical conditioning to overcome these technical barriers to the clinical translation of an effective small diameter vascular prosthesis is discussed. In conclusion, this review provides an overview of the historical development of tissue-engineered vascular grafts, highlighting specific areas warranting further research, and commentating on the outlook of a clinically feasible and therapeutically efficacious vascular prosthesis for small diameter arterial reconstruction.
Article
The use of exogenous biomolecules (BM) for the purpose of repairing and regenerating damaged cardiac tissue can yield serious side effects if used for prolonged periods. As well, such strategies can be cost prohibitive depending on the regiment and period of time applied. Alternatively, autologous monocytes/monocyte-derived macrophages (MDM) can provide a viable path towards generating an endogenous source of stimulatory BM. Biomaterials are often considered as delivery vehicles to generate unique profiles of such BM in tissues or to deliver autologous cells, that can influence the nature of BM produced by the cells. MDM cultured on a degradable polar hydrophobic ionic (D-PHI) polyurethane has previously demonstrated a propensity to increase select anti-inflammatory cytokines, and therefore there is good rationale to further investigate a broader spectrum of the cells’ BM in order to provide a more complete proteomic analysis of human MDM secretions induced by D-PHI. Further, it is of interest to assess the potential of such BM to influence cells involved in the reparative state of vital tissues such as those that affect cardiac cell function. Hence, this current study examines the proteomic profile of MDM secretions using mass spectrometry for the first time, along with ELISA, following their culture on D-PHI, and compares them to two important reference materials, poly(lactic-co-glycolic acid) (PLGA) and tissue culture polystyrene (TCPS). Secretions collected from D-PHI cultured MDM led to higher levels of regenerative BM, AGRN, TGFBI and ANXA5, but lower levels of pro-fibrotic BM, MMP7, IL-1β, IL-6 and TNFα, when compared to MDM secretions collected from PLGA and TCPS. In the application to cardiac cell function, the secretion collected from D-PHI cultured MDM led to more human cardiac fibroblast (HCFs) migration. A lower collagen gel contraction induced by MDM secretions collected from D-PHI was supported by gene array analysis for human fibrosis-related genes. The implication of these findings is that more tailored biomaterials such as D-PHI, may lead to a lower pro-inflammatory phenotype of macrophages when used in cardiac tissue constructs, thereby enabling the development of vehicles for the delivery of interventional therapies, or be applied as coatings for sensor implants in cardiac tissue that minimize fibrosis. The general approach of using synthetic biomaterials in order to induce MDM secretions in a manner that will guide favorable regeneration will be critical in making the choice of biomaterials for tissue regeneration work in the future. Statement of significance Immune modulation strategies currently applied in cardiac tissue repair are mainly based on the delivery of defined exogenous biomolecules. However, the use of such biomolecules may pose wide ranging systemic effects, thereby rendering them clinically less practical. The chemistry of biomaterials (used as a potential targeted delivery modality to circumvent the broad systemic effects of biomolecules) can not only affect acute and chronic toxicity but also alters the timeframe of the wound healing cascade. In this context, monocytes/monocyte-derive macrophages (MDM) can be harnessed as an immune modulating strategy to promote wound healing by an appropriate choice of the biomaterial. However, there are limited reports on the complete proteome analysis of MDM and their reaction of biomaterial related interventions on cardiac tissues and cells. No studies to date have demonstrated the complete proteome of MDM secretions when these cells were cultured on a non-traditional immune modulatory ionomeric polyurethane D-PHI film. This study demonstrated that MDM cultured on D-PHI expressed significantly higher levels of AGRN, TGFBI and ANXA5 but lower levels of MMP7, IL-1β, IL-6 and TNFα when compared to MDM cultured on a well-established degradable biomaterials in the medical field, e.g. PLGA and TCPS, which are often used as the relative standards for cell culture work in the biomaterials field. The implications of these findings have relevance to the repair of cardiac tissues. In another aspect of the work, human cardiac fibroblasts showed significantly lower contractility (low collagen gel contraction and low levels of ACTA2) when cultured in the presence of MDM secretions collected after culturing them on D-PHI compared to PLGA and TCPS. The findings place emphasis on the importance of making the choice of biomaterials for tissue engineering and regenerative medicine applied to their use in cardiac tissue repair.