|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | Regulatory Influence of Scaffolds on Cell Behavior: How Cells Decode Biomaterials. Curr Pharm Biotechnol. 2010 Nov 2; Authors: Pennesi G, Scaglione S, Giannoni P, Quarto R A stem cell is defined as a cell able to self-renew and at the same time to generate one or more specialized progenies. In the adult organism, stem cells need a specific microenvironment where to reside. This tissue-specific instructive microenvironment, hosting stem cells and governing their fate, is composed of extracellular matrix and soluble molecules. Cell-matrix and cell-cell interactions also contribute to the specifications of this milieu, regarded as a whole unitary system and referred to as "niche". For many stem cell systems a niche has been identified, but only partially defined. In regenerative medicine and tissue engineering, biomaterials are used to deliver stem cells in specific anatomical sites where a regenerative process is needed. In this context, biomaterials have to provide informative microenvironments mimicking a physiological niche. Stem cells may read and decode any biomaterial and modify their behavior and fate accordingly. Any material is therefore informative in the sense that its intrinsic nature and structure will anyway transmit a signal that will have to be decoded by colonizing cells. We still know very little of how to create local microenvironments, or artificial niches, that will govern stem cells behavior and their terminal fate. Here we will review some characteristics identifying specific niches and some of the requirements allowing stem cells differentiation processes. We will discuss on those biomaterials that are being projected/engineered/manufactured to gain the informative status necessary to drive proper molecular cross-talk and cell differentiation; specific examples will be proposed for bone and cartilage substitutes. PMID: 21044012 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Simultaneous Injection of Autologous Mononuclear Cells with TACE in HCC Patients; Preliminary Study. J Gastrointest Cancer. 2010 Nov 3; Authors: Ismail A, Aldorry A, Shaker M, Elwekeel R, Mokbel K, Zakaria D, Meshaal A, Eldeen FZ, Selim A BACKGROUND: The discovery of the pluripotent stem cells made the prospect of cell therapy and tissue regeneration a clinical reality, especially with the evidence of contribution of the stem cells of bone marrow origin in hepatic regeneration. Infusion of bone marrow stem cells before trans-arterial chemoembolization may help to increase liver volume and consequently increase hepatic reserve in patients with HCC, and this may improve the outcome of this procedure. MATERIALS AND METHODS: Four Child B class patients with unresectable hepatocellular carcinoma treated by transarterial chemoembolization were injected with autologous bone marrow mononuclear layer containing stem cell in the hepatic artery feeding the contralateral lobe of the liver in the same session, follow-up of the patients was done by doing liver profile and CT liver volumetry before the surgery and 3 months later. RESULTS: We observed that patients receiving stem cell therapy simultaneously with TACE had shown a significant improvement in biological and volumetric parameters of liver function compared to those historically reported of patients receiving TACE only who usually shows deterioration of liver parameters. CONCLUSION: BMC infusion into the hepatic artery synchronized with TACE for patients with chronic liver disease complicated with HCC is safe, feasible, and demonstrated an improvement in both biological and radiological volumetric parameters. PMID: 21046282 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Investigating regeneration and functional integration of CNS neurons: Lessons from zebrafish genetics and other fish species. Biochim Biophys Acta. 2010 Oct 28; Authors: Fleisch VC, Fraser B, Allison WT Zebrafish possess a robust, innate CNS regenerative ability. Combined with their genetic tractability and vertebrate CNS architecture, this ability makes zebrafish an attractive model to gain requisite knowledge for clinical CNS regeneration. In treatment of neurological disorders, one can envisage replacing lost neurons through stem cell therapy or through activation of latent stem cells in the CNS. Here we review the evidence that radial glia are a major source of CNS stem cells in zebrafish and thus activation of radial glia is an attractive therapeutic target. We discuss the regenerative potential and the molecular mechanisms thereof, in the zebrafish spinal cord, retina, optic nerve and higher brain centres. We evaluate various cell ablation paradigms developed to induce regeneration, with particular emphasis on the need for (high throughput) indicators that neuronal regeneration has restored sensory or motor function. We also examine the potential confound that regeneration imposes as the community develops zebrafish models of neurodegeneration. We conclude that zebrafish combine several characters that make them a potent resource for testing hypotheses and discovering therapeutic targets in functional CNS regeneration. PMID: 21044883 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Regulatory Influence of Scaffolds on Cell Behavior: How Cells Decode Biomaterials. Curr Pharm Biotechnol. 2010 Nov 2; Authors: Pennesi G, Scaglione S, Giannoni P, Quarto R A stem cell is defined as a cell able to self-renew and at the same time to generate one or more specialized progenies. In the adult organism, stem cells need a specific microenvironment where to reside. This tissue-specific instructive microenvironment, hosting stem cells and governing their fate, is composed of extracellular matrix and soluble molecules. Cell-matrix and cell-cell interactions also contribute to the specifications of this milieu, regarded as a whole unitary system and referred to as "niche". For many stem cell systems a niche has been identified, but only partially defined. In regenerative medicine and tissue engineering, biomaterials are used to deliver stem cells in specific anatomical sites where a regenerative process is needed. In this context, biomaterials have to provide informative microenvironments mimicking a physiological niche. Stem cells may read and decode any biomaterial and modify their behavior and fate accordingly. Any material is therefore informative in the sense that its intrinsic nature and structure will anyway transmit a signal that will have to be decoded by colonizing cells. We still know very little of how to create local microenvironments, or artificial niches, that will govern stem cells behavior and their terminal fate. Here we will review some characteristics identifying specific niches and some of the requirements allowing stem cells differentiation processes. We will discuss on those biomaterials that are being projected/engineered/manufactured to gain the informative status necessary to drive proper molecular cross-talk and cell differentiation; specific examples will be proposed for bone and cartilage substitutes. PMID: 21044012 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Network of WNT and Other Regulatory Signaling Cascades in Pluripotent Stem Cells and Cancer Stem Cells. Curr Pharm Biotechnol. 2010 Nov 2; Authors: Katoh M Canonical WNT signaling activation leads to transcriptional up-regulation of FGF ligand, Notch ligand, non-canonical WNT ligand, WNT antagonist, TGFβ antagonist, and MYC. Non-canonical WNT signals inhibit canonical WNT signaling by using MAP3K7-NLK signaling cascade. Hedgehog up-regulates Notch ligand, WNT antagonist, BMP antagonists, and MYCN. TGFβ up-regulates non-canonical WNT ligand, CDK inhibitors, and NANOG, while BMP up-regulates Hedgehog ligand. Based on these mutual regulations, WNT, FGF, Notch, Hedgehog, and TGFβ/BMP signaling cascades constitute the stem-cell signaling network, which plays a key role in the maintenance or homeostasis of pluripotent stem cells and cancer stem cells. Human embryonic stem cells (ESCs) are supported by FGF and TGFβ/Nodal/Activin signals, whereas mouse ESCs by LIF and canonical WNT signals. Combination of TGFβ inhibitor and canonical WNT activator alter the character of human induced pluripotent stem cells (iPSCs) from human ESC-like to mouse ESC-like. Fine-tuning of WNT, FGF, Notch, TGFβ/BMP, and Hedgehog signaling network by using small-molecule compounds could open the door for regenerative medicine utilizing pluripotent stem cells without tumorigenic potential. Because FGF, Hedgehog, TGFβ, and non-canonical WNT signals synergistically induce EMT regulators, such as Snail (SNAI1), Slug (SNAI2), TWIST, and ZEB2 (SIP1), tumor-stromal interaction at the invasion front aids cancer stem cells to acquire more malignant phenotype. Cancer stem cells occur as mimetics of normal tissue stem cells based on germ-line variation, epigenetic change, and somatic mutation of stem-cell signaling components, and then acquire more malignant phenotype based on accumulation of additional epigenetic and genetic alterations, and tumor-stromal interaction at the invasion front. PMID: 21044011 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Comparison of Three Methods for the Derivation of a Biologic Scaffold Composed of Adipose Tissue Extracellular Matrix. Tissue Eng Part C Methods. 2010 Nov 3; Authors: Brown BN, Fruend JM, Li H, Rubin PJ, Reing JE, Jeffries EM, Wolf MT, Tottey S, Barnes CA, Ratner B, Badylak SF Extracellular matrix (ECM) based scaffold materials have been used successfully in both preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. Results of numerous studies have shown that ECM scaffolds are capable of supporting the growth and differentiation of multiple cell types in vitro and of acting as inductive templates for constructive tissue remodeling following implantation in vivo. Adipose tissue represents a potentially abundant source of ECM and may represent an ideal substrate for the growth and adipogenic differentiation of stem cells harvested from this tissue. Numerous studies have shown that the methods by which ECM scaffold materials are prepared have a dramatic effect upon both the biochemical and structural properties of the resultant ECM scaffold material as well as the ability of the material to support a positive tissue remodeling outcome following implantation. The objective of the present study was to characterize the adipose ECM material resulting from three methods of decellularization to determine the most effective method for the derivation of an adipose tissue ECM scaffold which was largely free of potentially immunogenic cellular content while retaining tissue-specific structural and functional components as well as the ability to support the growth and adipogenic differentiation of adipose derived stem cells (ADSC). The results show that each of the decellularization methods produced an adipose ECM scaffold that was distinct from both a structural and biochemical perspective, emphasizing the importance of the decellularization protocol used to produce adipose ECM scaffolds. Further, the results suggest that the adipose ECM scaffolds produced using the methods described herein are capable of supporting the maintenance and adipogenic differentiation of ADSCs and may represent effective substrates for use in tissue engineering and regenerative medicine approaches to soft tissue reconstruction. PMID: 21043998 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Enhanced reporter gene assay for the detection of osteogenic differentiation. Tissue Eng Part C Methods. 2010 Nov 3; Authors: Feichtinger GA, Morton T, Zimmermann A, Banerjee A, Dopler D, Redl H, van Griensven M Detection of osteogenic differentiation is crucial for bone tissue engineering. Despite established standard end point assays, there is increasing demand for methods allowing non-invasive kinetic differentiation monitoring. Reporter gene assays employing tissue-specific promoters and suitable reporter genes fulfil these requirements. Many promoters, however, exhibit only weak cis-activating potential, thus limiting their application to generate sensitive reporter gene assays. Therefore, the aim of this study was to design a reporter gene assay employing elements of the murine osteocalcin promoter coupled to a viral enhancer for signal amplification. Additionally, the system's practicability was enhanced by introducing a secreted luciferase as a quantifiable reporter gene. The constructs were tested in C2C12 cells stimulated with recombinant human bone morphogenetic protein 2 (rhBMP2) for osteogenic differentiation in 2D and 3D culture. Osteogenic differentiation was confirmed by standard assays for osteogenesis. The reporter gene signal was detected through a secreted luciferase or fluorescence microscopy for enhanced yellow fluorescent protein. The constructs exhibited strong activation upon treatment with rhBMP2. Weak background expression was observable in negative controls, attributed to the pan-active viral enhancer. In conclusion, a novel enhancer/tissue-specific promoter combination allows specific signal-amplified, kinetic monitoring of osteogenic differentiation in a non sample-destructive manner. PMID: 21043997 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Azine-Based Receptor for Recognition of Hg(2+) Ion: Crystallographic Evidence and Imaging Application in Live Cells. Org Lett. 2010 Nov 2; Authors: Suresh M, Mandal AK, Saha S, Suresh E, Mandoli A, Di Liddo R, Parnigotto PP, Das A A newly synthesized azine-based receptor (L) is found to show remarkable specificity toward the Hg(2+) ion in aqueous media over other metal ions. Coordination of L to Hg(2+) induces a detectable change in color and a turn-on fluorescence response. Restricted C═N isomerization of the azine moieties in the excited state as well as the Photoinduced Electron Transfer (PET) involving the lone pair of electrons of N(1)/N(2) on coordination of L to the Hg(2+) ion account for the turn-on fluorescence response. This reagent could be used for imaging the accumulation of Hg(2+) ions in Epithelial cell line KB 31 cells. PMID: 21043523 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | The individual-cell-based cryo-chip for the cryopreservation, manipulation and observation of spatially identifiable cells. I: methodology. BMC Cell Biol. 2010;11:54 Authors: Deutsch M, Afrimzon E, Namer Y, Shafran Y, Sobolev M, Zurgil N, Deutsch A, Howitz S, Greuner M, Thaele M, Zimmermann H, Meiser I, Ehrhart F BACKGROUND: Cryopreservation is the only widely applicable method of storing vital cells for nearly unlimited periods of time. Successful cryopreservation is essential for reproductive medicine, stem cell research, cord blood storage and related biomedical areas. The methods currently used to retrieve a specific cell or a group of individual cells with specific biological properties after cryopreservation are quite complicated and inefficient. RESULTS: The present study suggests a new approach in cryopreservation, utilizing the Individual Cell-based Cryo-Chip (i3C). The i3C is made of materials having appropriate durability for cryopreservation conditions. The core of this approach is an array of picowells, each picowell designed to maintain an individual cell during the severe conditions of the freezing--thawing cycle and accompanying treatments. More than 97% of cells were found to retain their position in the picowells throughout the entire freezing--thawing cycle and medium exchange. Thus the comparison between pre-freezing and post-thawing data can be achieved at an individual cell resolution. The intactness of cells undergoing slow freezing and thawing, while residing in the i3C, was found to be similar to that obtained with micro-vials. However, in a fast freezing protocol, the i3C was found to be far superior. CONCLUSIONS: The results of the present study offer new opportunities for cryopreservation. Using the present methodology, the cryopreservation of individual identifiable cells, and their observation and retrieval, at an individual cell resolution become possible for the first time. This approach facilitates the correlation between cell characteristics before and after the freezing--thawing cycle. Thus, it is expected to significantly enhance current cryopreservation procedures for successful regenerative and reproductive medicine. PMID: 20609216 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Perspectives on adipose-derived stem/stromal cells as potential treatment for scarred vocal folds: opportunity and challenges. Curr Stem Cell Res Ther. 2010 Jun;5(2):175-81 Authors: Kumai Y, Kobler JB, Herrera VL, Zeitels SM Regenerative therapy using stem cells for the treatment of vocal fold wound healing and fibrosis is a very active area of research in Otolaryngology. Although modern phonosurgical methods can deal with many types of vocal fold pathology, vocal fold scar remains a clinical challenge. Trauma (e.g. vocal abuse, phonosurgery) and inflammation (e.g. laryngitis) are the two main causes of the vocal fold scarring. Several recent reviews detail the problem of vocal fold scarring and the array of possible solutions under investigation. The search for solutions includes autologous tissues, biomaterial implants, growth factors, anti-fibrotic agents and stem cells. This review focuses on emerging research on stem cells for vocal fold regeneration and our own studies of interactions between adipose-derived stem/stromal cells and vocal fold fibroblasts using an in vitro model. While clearly an opportunity, the challenging approach of treating vocal scarring using ASCs has just started. For future in vivo studies, improvements in cell viability and markers of stem-cell differentiation into normal fibroblasts are needed. The roles of stem cell-derived cytokines in paracrine signaling need to be further explored at a cellular level in vitro, and then extended to in vivo experiments. PMID: 19941448 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Comparison of Corneal Epitheliotrophic Capacity Among Different Human Blood-derived Preparations. Cornea. 2010 Oct 28; Authors: Shen EP, Hu FR, Lo SC, Chen YM, Sun YC, Lin CT, Chen WL PURPOSE:: To compare the corneal epitheliotrophic capacity of different human blood-derived preparations, including cord blood serum (CBS), peripheral blood serum (PBS), and fresh frozen plasma (FFP) on bovine corneal epithelial cells. MATERIALS AND METHODS:: The concentrations of epithelial growth factor, transforming growth factor β1, insulin-like growth factor 1, hyaluronic acid, fibronectin, albumin, glucose, and calcium in different human blood derivatives were evaluated using enzyme-linked immunosorbent assay or biochemical methods. Cultivated bovine corneal epithelial cells were incubated with various blood derivatives, and cell proliferation, migration, and differentiation were evaluated by colorimetric assay, Boyden chamber chemotaxis assay, wounding assay, scanning electron microscopy, and transepithelial electric resistance measurements. Wound closure was assessed using a scratch-induced directional wounding assay. RESULTS:: Of the 3 human blood derivatives evaluated, CBS had the highest concentrations of epithelial growth factor, transforming growth factor β1, and hyaluronic acid (P < 0.05). FFP had the lowest concentration of calcium and the highest concentration of glucose (P < 0.05). CBS demonstrated the highest ability to promote cellular proliferation, followed by PBS and FFP (P < 0.05). CBS was also the best in promoting cellular differentiation because scanning electron microscopy demonstrated coherent monolayers of flattened and polygonal-shaped cells with evenly distributed microvilli. Transepithelial electric resistance was noted to be the highest for cells incubated in CBS, indicating formation of well-differentiated cells with functional tight junction (P < 0.05). Cells cultivated with FFP were the least capable of promoting proliferation, migration, and differentiation. CONCLUSIONS:: Different human blood derivatives may have different concentrations of epitheliotrophic factors. CBS is generally superior to PBS in promoting corneal epithelial proliferation and differentiation. PMID: 21045671 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Formation of microvilli and phosphorylation of ERM family proteins by CD43, a potent inhibitor for cell adhesion: Cell detachment is a potential cue for ERM phosphorylation and organization of cell morphology. Cell Adh Migr. 2011 Mar 11;5(2) Authors: Yamane J, Ohnishi H, Sasaki H, Narimatsu H, Ohgushi H, Tachibana K CD43/sialophorin/leukosialin, a common leukocyte antigen, is known as an inhibitor for cell adhesion. The ectodomain of CD43 is considered as a molecular barrier for cell adhesion, while the cytoplasmic domain has a binding site for Ezrin/Radixin/Moesin (ERM). We found expression of CD43 induced cell rounding, inhibition of cell re-attachment, augmentation of microvilli and phosphorylation of ERM in HEK293T cells. Mutant studies revealed the ectodomain of CD43, but not the intracellular domain, essential and sufficient for all these phenomena. We also found that forced cell detachment by itself induced phosphorylation of ERM in HEK293T cells. Taken together, these findings indicate that inhibition of cell adhesion by the ectodomain of CD43 induces phosphorylation of ERM, microvilli formation and eventual cell rounding. Furthermore, our study suggests a novel possibility that cell detachment itself induces activation of ERM and modification of cell shape. PMID: 21045567 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Comparison of Three Methods for the Derivation of a Biologic Scaffold Composed of Adipose Tissue Extracellular Matrix. Tissue Eng Part C Methods. 2010 Nov 3; Authors: Brown BN, Fruend JM, Li H, Rubin PJ, Reing JE, Jeffries EM, Wolf MT, Tottey S, Barnes CA, Ratner B, Badylak SF Extracellular matrix (ECM) based scaffold materials have been used successfully in both preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. Results of numerous studies have shown that ECM scaffolds are capable of supporting the growth and differentiation of multiple cell types in vitro and of acting as inductive templates for constructive tissue remodeling following implantation in vivo. Adipose tissue represents a potentially abundant source of ECM and may represent an ideal substrate for the growth and adipogenic differentiation of stem cells harvested from this tissue. Numerous studies have shown that the methods by which ECM scaffold materials are prepared have a dramatic effect upon both the biochemical and structural properties of the resultant ECM scaffold material as well as the ability of the material to support a positive tissue remodeling outcome following implantation. The objective of the present study was to characterize the adipose ECM material resulting from three methods of decellularization to determine the most effective method for the derivation of an adipose tissue ECM scaffold which was largely free of potentially immunogenic cellular content while retaining tissue-specific structural and functional components as well as the ability to support the growth and adipogenic differentiation of adipose derived stem cells (ADSC). The results show that each of the decellularization methods produced an adipose ECM scaffold that was distinct from both a structural and biochemical perspective, emphasizing the importance of the decellularization protocol used to produce adipose ECM scaffolds. Further, the results suggest that the adipose ECM scaffolds produced using the methods described herein are capable of supporting the maintenance and adipogenic differentiation of ADSCs and may represent effective substrates for use in tissue engineering and regenerative medicine approaches to soft tissue reconstruction. PMID: 21043998 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Enhanced reporter gene assay for the detection of osteogenic differentiation. Tissue Eng Part C Methods. 2010 Nov 3; Authors: Feichtinger GA, Morton T, Zimmermann A, Banerjee A, Dopler D, Redl H, van Griensven M Detection of osteogenic differentiation is crucial for bone tissue engineering. Despite established standard end point assays, there is increasing demand for methods allowing non-invasive kinetic differentiation monitoring. Reporter gene assays employing tissue-specific promoters and suitable reporter genes fulfil these requirements. Many promoters, however, exhibit only weak cis-activating potential, thus limiting their application to generate sensitive reporter gene assays. Therefore, the aim of this study was to design a reporter gene assay employing elements of the murine osteocalcin promoter coupled to a viral enhancer for signal amplification. Additionally, the system's practicability was enhanced by introducing a secreted luciferase as a quantifiable reporter gene. The constructs were tested in C2C12 cells stimulated with recombinant human bone morphogenetic protein 2 (rhBMP2) for osteogenic differentiation in 2D and 3D culture. Osteogenic differentiation was confirmed by standard assays for osteogenesis. The reporter gene signal was detected through a secreted luciferase or fluorescence microscopy for enhanced yellow fluorescent protein. The constructs exhibited strong activation upon treatment with rhBMP2. Weak background expression was observable in negative controls, attributed to the pan-active viral enhancer. In conclusion, a novel enhancer/tissue-specific promoter combination allows specific signal-amplified, kinetic monitoring of osteogenic differentiation in a non sample-destructive manner. PMID: 21043997 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Differentiation of human multipotent dermal fibroblasts into islet-like cell clusters. BMC Cell Biol. 2010;11:46 Authors: Bi D, Chen FG, Zhang WJ, Zhou GD, Cui L, Liu W, Cao Y BACKGROUND: We have previously obtained a clonal population of cells from human foreskin that is able to differentiate into mesodermal, ectodermal and endodermal progenies. It is of great interest to know whether these cells could be further differentiated into functional insulin-producing cells. RESULTS: Sixty-one single-cell-derived dermal fibroblast clones were established from human foreskin by limiting dilution culture. Of these, two clones could be differentiated into neuron-, adipocyte- or hepatocyte-like cells under certain culture conditions. In addition, those two clones were able to differentiate into islet-like clusters under pancreatic induction. Insulin, glucagon and somatostatin were detectable at the mRNA and protein levels after induction. Moreover, the islet-like clusters could release insulin in response to glucose in vitro. CONCLUSIONS: This is the first study to demonstrate that dermal fibroblasts can differentiate into insulin-producing cells without genetic manipulation. This may offer a safer cell source for future stem cell-based therapies. PMID: 20579360 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Multiple mesodermal lineage differentiation of Apodemus sylvaticus embryonic stem cells in vitro. BMC Cell Biol. 2010;11:42 Authors: Wang T, Mao FF, Lai W, Li W, Yu W, Wang Z, Zhang L, Zhang J, Niu J, Zhang X, Lahn BT, Xiang AP BACKGROUND: Embryonic stem (ES) cells have attracted significant attention from researchers around the world because of their ability to undergo indefinite self-renewal and produce derivatives from the three cell lineages, which has enormous value in research and clinical applications. Until now, many ES cell lines of different mammals have been established and studied. In addition, recently, AS-ES1 cells derived from Apodemus sylvaticus were established and identified by our laboratory as a new mammalian ES cell line. Hence further research, in the application of AS-ES1 cells, is warranted. RESULTS: Herein we report the generation of multiple mesodermal AS-ES1 lineages via embryoid body (EB) formation by the hanging drop method and the addition of particular reagents and factors for induction at the stage of EB attachment. The AS-ES1 cells generated separately in vitro included: adipocytes, osteoblasts, chondrocytes and cardiomyocytes. Histochemical staining, immunofluorescent staining and RT-PCR were carried out to confirm the formation of multiple mesodermal lineage cells. CONCLUSIONS: The appropriate reagents and culture milieu used in mesodermal differentiation of mouse ES cells also guide the differentiation of in vitro AS-ES1 cells into distinct mesoderm-derived cells. This study provides a better understanding of the characteristics of AS-ES1 cells, a new species ES cell line and promotes the use of Apodemus ES cells as a complement to mouse ES cells in future studies. PMID: 20565897 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Development of bone-like composites via the polymer-induced liquid-precursor (PILP) process. Part 1: influence of polymer molecular weight. Acta Biomater. 2010 Sep;6(9):3676-86 Authors: Jee SS, Thula TT, Gower LB Bone is an organic-inorganic composite consisting primarily of collagen fibrils and hydroxyapatite crystals intricately interlocked to provide skeletal and metabolic functions. Non-collagenous proteins (NCPs) are also present, and although only a minor component, the NCPs are thought to play an important role in modulating the mineralization process. During secondary bone formation, an interpenetrating structure is created by intrafibrillar mineralization of the collagen matrix. Many researchers have tried to develop bone-like collagen-hydroxyapatite (HA) composites via the conventional crystallization process of nucleation and growth. While those methods have been successful in inducing heterogeneous nucleation of HA on the surface of collagen scaffolds, they have failed to produce a composite with the interpenetrating nanostructured architecture of bone. Our group has shown that intrafibrillar mineralization of type I collagen can be achieved using a polymer-induced liquid-precursor (PILP) process. In this process, acidic polypeptides are included in the mineralization solution to mimic the function of the acidic NCPs, and in vitro studies have found that acidic peptides such as polyaspartate induce a liquid-phase amorphous mineral precursor. Using this PILP process, we have been able to prepare collagen-HA composites with the fundamental nanostructure of bone, wherein HA nanocrystals are embedded within the collagen fibrils. This study shows that through further optimization a very high degree of mineralization can be achieved, with compositions matching that of bone. Synthetic collagen sponges were mineralized with calcium phosphate while analyzing various parameters of the reaction, with the focus of this report on the molecular weight of the polymeric process-directing agent. In order to determine whether intrafibrillar mineralization was achieved, an in-depth characterization of the mineralized composites was performed, including wide-angle X-ray diffraction, electron microscopy and thermogravimetric analyses. The results of this work lead us closer to the development of bone-like collagen-HA composites that could become the next generation of synthetic bone grafts. PMID: 20359554 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Biodegradable and injectable cure-on-demand polyurethane scaffolds for regeneration of articular cartilage. Acta Biomater. 2010 Sep;6(9):3471-81 Authors: Werkmeister JA, Adhikari R, White JF, Tebb TA, Le TP, Taing HC, Mayadunne R, Gunatillake PA, Danon SJ, Ramshaw JA This paper describes the synthesis and characterization of an injectable methacrylate functionalized urethane-based photopolymerizable prepolymer to form biodegradable hydrogels. The tetramethacrylate prepolymer was based on the reaction between two synthesized compounds, diisocyanato poly(ethylene glycol) and monohydroxy dimethacrylate poly(epsilon-caprolactone) triol. The final prepolymer was hydrated with phosphate-buffered saline (pH 7.4) to yield a biocompatible hydrogel containing up to 86% water. The methacrylate functionalized prepolymer was polymerized using blue light (450 nm) with an initiator, camphorquinone and a photosensitizer, N,N-dimethylaminoethyl methacrylate. The polymer was stable in vitro in culture media over the 28 days tested (1.9% mass loss); in the presence of lipase, around 56% mass loss occurred over the 28 days in vitro. Very little degradation occurred in vivo in rats over the same time period. The polymer was well tolerated with very little capsule formation and a moderate host tissue response. Human chondrocytes, seeded onto Cultispher-S beads, were viable in the tetramethacrylate prepolymer and remained viable during and after polymerization. Chondrocyte-bead-polymer constructs were maintained in static and spinner culture for 8 weeks. During this time, cells remained viable, proliferated and migrated from the beads through the polymer towards the edge of the polymer. New extracellular matrix (ECM) was visualized with Masson's trichrome (collagen) and Alcian blue (glycosaminoglycan) staining. Further, the composition of the ECM was typical for articular cartilage with prominent collagen type II and type VI and moderate keratin sulphate, particularly for tissue constructs cultured under dynamic conditions. PMID: 20211278 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Adipose-derived stem cells. Curr Stem Cell Res Ther. 2010 Jun;5(2):94 Authors: Ogawa R PMID: 19941462 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Aesthetic cardiology: adipose-derived stem cells for myocardial repair. Curr Stem Cell Res Ther. 2010 Jun;5(2):145-52 Authors: Palpant NJ, Metzger JM Stem cell biology has increasingly gained scientific and public interest in recent years. In particular, the use of stem cells for treatment of heart disease has been strongly pursued within the scientific and medical communities. Significant effort has gone into the use of adult tissue-derived stem cells for cardiac repair including bone marrow, blood, and cardiac-derived cell populations. Significant interest in this area has been balanced by the difficulties of understanding stem cells, cardiac injury, and the amalgamation of these areas of investigation in translational medicine. Recent studies have emerged on adipose-derived stem cells which show the potential for cardiac lineage development in vitro and may have application in cell-mediated in vivo therapy for the diseased heart. This review provides a summary of current findings within the field of adipose-derived stem cell biology regarding their cardiac differentiation potential. PMID: 19941452 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Cornea and ocular surface treatment. Curr Stem Cell Res Ther. 2010 Jun;5(2):195-204 Authors: De Miguel MP, Alio JL, Arnalich-Montiel F, Fuentes-Julian S, de Benito-Llopis L, Amparo F, Bataille L In addition to being a protective shield, the cornea represents two thirds of the eye's refractive power. Corneal pathology can affect one or all of the corneal layers, producing corneal opacity. Although full corneal thickness keratoplasty has been the standard procedure, the ideal strategy would be to replace only the damaged layer. Current difficulties in corneal transplantation, mainly immune rejection and shortage of organ supply, place more emphasis on the development of artificial corneas. Bioengineered corneas range from prosthetic devices that solely address the replacement of the corneal function, to tissue-engineered hydrogels that allow regeneration of the tissue. Recently, major advances in the biology of corneal stem cells have been achieved. However, the therapeutic use of these stem cell types has the disadvantage of needing an intact stem cell compartment, which is usually damaged. In addition, long ex vivo culture is needed to generate enough cell numbers for transplantation. In the near future, combination of advanced biomaterials with cells from abundant outer sources will allow advances in the field. For the former, magnetically aligned collagen is one of the most promising ones. For the latter, different cell types will be optimal: 1) for epithelial replacement: oral mucosal epithelium, ear epidermis, or bone marrow- mesenchymal stem cells, 2) for stromal regeneration: adipose-derived stem cells and 3) for endothelial replacement, the possibility of in vitro directed differentiation of adipose-derived stem cells towards endothelial cells provides an exciting new approach. PMID: 19941445 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Expansion of adipose tissue mesenchymal stromal progenitors in serum-free medium supplemented with virally inactivated allogeneic human platelet lysate. Transfusion. 2010 Nov 2; Authors: Shih DT, Chen JC, Chen WY, Kuo YP, Su CY, Burnouf T BACKGROUND: Single-donor or pooled platelet lysates (PL) can substitute for fetal bovine serum (FBS) for mesenchymal stromal cell (MSC) expansion. However, for clinical applications of MSCs, the use of virally inactivated PL would be desirable. Recently, we have developed a solvent/detergent (S/D)-treated human PL preparation (S/D-PL) rich in growth factors. The capacity to use this virally inactivated preparation for MSC expansion needs to be evaluated. STUDY DESIGN AND METHODS: Platelet concentrates were treated by S/D (1% tri-n-butyl phosphate and 1% Triton X-45), extracted by oil, purified by C18 hydrophobic interaction chromatography, and sterile filtered. S/D-PL was compared to FBS as a medium supplement (10% vol/vol) for isolating, maintaining, and expanding adipose tissue-derived MSCs (AT-MSCs). Cell morphology; proliferation kinetics; immunophenotype; differentiation capacity toward the chondrogenic, osteogenic, and osteogenic lineages; and cytokine antibody array were assessed. RESULTS: AT-MSCs had a typical spindle morphology and proliferated in S/D-PL at least as well as in FBS. Immunophenotype at Passage 7 was characteristic of MSCs and similar for both culture conditions. Differentiation capacity into the three lineages was maintained and chondrogenesis was enhanced by S/D-PL. In a 120 human cytokine antibody array analysis, 73 cytokines were detected in S/D-PL, including 22 with a concentration higher than in FBS. CONCLUSION: S/D-PL is an alternative to FBS for AT-MSC maintenance and expansion, does not compromise the differentiation capacity nor the immunophenotype, and may accelerate chondrogenesis. S/D-PL protocols for MSC clinical scale-up may represent a major step toward challenging new use in stem cell therapies. PMID: 21044088 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Adipose-derived stem cells. Curr Stem Cell Res Ther. 2010 Jun;5(2):94 Authors: Ogawa R PMID: 19941462 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
No comments:
Post a Comment