|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | [Stem cell therapy for neurological disorders.] Ugeskr Laeger. 2010 Sep 20;172(38):2604-2607 Authors: Meyer M, Jensen P, Rasmussen JZ Intrastriatal, foetal neural transplants can ameliorate symptoms in patients with Parkinson's and Huntington's disease, although not stop the primary cell-loss. Several issues must, however, be addressed before general or extended clinical use of cell therapy in neurodegenerative diseases can become a reality. Improvements include standardized and safe master cell-lines derived from human embryonic stem cells, induced pluripotent stem cells and neural stem cells. Cells from these sources are expected to become available for cell replacement therapies or therapeutic production of trophic, anti-inflammatory and restorative factors within a few years. PMID: 20920404 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Engineered Biocompatible Nanoparticles for in Vivo Imaging Applications. J Am Chem Soc. 2010 Oct 4; Authors: Chen S, Wang L, Duce SL, Brown S, Lee S, Melzer A, Cuschieri SA, André P Iron-platinum alloy nanoparticles (FePt NPs) are extremely promising candidates for the next generation of contrast agents for magnetic resonance (MR) diagnostic imaging and MR-guided interventions, including hyperthermic ablation of solid cancers. FePt has high Curie temperature, saturation magnetic moment, magneto-crystalline anisotropy, and chemical stability. We describe the synthesis and characterization of a family of biocompatible FePt NPs suitable for biomedical applications, showing and discussing that FePt NPs can exhibit low cytotoxicity. The importance of engineering the interface of strongly magnetic NPs using a coating allowing free aqueous permeation is demonstrated to be an essential parameter in the design of new generations of diagnostic and therapeutic MRI contrast agents. We report effective cell internalization of FePt NPs and demonstrate that they can be used for cellular imaging and in vivo MRI applications. This opens the way for several future applications of FePt NPs, including regenerative medicine and stem cell therapy in addition to enhanced MR diagnostic imaging. PMID: 20919679 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | Late last June, the chairman of the California stem cell agency, Robert Klein, dismissed concerns that biotech firms are not getting a fair shake at the agency's $3 billion in research awards. That's not what he has heard, he told CIRM directors. In fact, Klein said, he had just received an award from a national industry group.
Two months later, leaders of the Northern California biotech | | | | | | | | | | | | | | | | | | | | | | | | The California Stem Cell Report has been named one of the top 13 stem cell blogs internationally by Webicina.com, a physician-directed Web site aimed at helping physicians and patients obtain reliable information.
Webicina prepared the list because of the plethora of misleading and inaccurate information on the Web. In addition to this blog, the list of best blogs included the Cancer Stem Cell | | | | | | | | | | | | | | | | | | | | | | | | | Adipose-derived mesenchymal stem cells markedly attenuate brain infarct size and improve neurological function in rats. J Transl Med. 2010;8:63 Authors: Leu S, Lin YC, Yuen CM, Yen CH, Kao YH, Sun CK, Yip HK BACKGROUND: The therapeutic effect of adipose-derived mesenchymal stem cells (ADMSCs) on brain infarction area (BIA) and neurological status in a rat model of acute ischemic stroke (IS) was investigated. METHODS: Adult male Sprague-Dawley (SD) rats (n = 30) were divided into IS plus intra-venous 1 mL saline (at 0, 12 and 24 h after IS induction) (control group) and IS plus intra-venous ADMSCs (2.0 x 106) (treated interval as controls) (treatment group) after occlusion of distal left internal carotid artery. The rats were sacrificed and brain tissues were harvested on day 21 after the procedure. RESULTS: The results showed that BIA was larger in control group than in treatment group (p < 0.001). The sensorimotor functional test (Corner test) identified a higher frequency of turning movement to left in control group than in treatment group (p < 0.05). mRNA expressions of Bax, caspase 3, interleukin (IL)-18, toll-like receptor-4 and plasminogen activator inhibitor-1 were higher, whereas Bcl-2 and IL-8/Gro were lower in control group than in treatment group (all p < 0.05). Western blot demonstrated a lower CXCR4 and stromal-cell derived factor-1 (SDF-1) in control group than in treatment group (all p < 0.01). Immunohistofluorescent staining showed lower expressions of CXCR4, SDF-1, von Willebran factor and doublecortin, whereas the number of apoptotic nuclei on TUNEL assay was higher in control group than in treatment group (all p < 0.001). Immunohistochemical staining showed that cellular proliferation and number of small vessels were lower but glial fibrillary acid protein was higher in control group than in treatment group (all p < 0.01). CONCLUSIONS: ADMSC therapy significantly limited BIA and improved sensorimotor dysfunction after acute IS. PMID: 20584315 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Addition of hydroxyapatite improves stiffness, interconnectivity and osteogenic potential of a highly porous collagen-based scaffold for bone tissue regeneration. Eur Cell Mater. 2010;20:218-30 Authors: Gleeson JP, Plunkett NA, O'Brien FJ There is an enduring and unmet need for a bioactive, load-bearing tissue-engineering scaffold, which is biocompatible, biodegradable and capable of facilitating and promoting osteogenesis when implanted in vivo. This study set out to develop a biomimetic scaffold by incorporating osteoinductive hydroxyapatite (HA) particles into a highly porous and extremely biocompatible collagen-based scaffold developed within our laboratory over the last number of years to improve osteogenic performance. Specifically we investigated how the addition of discrete quantities of HA affected scaffold porosity, interconnectivity, mechanical properties, in vitro mineralisation and in vivo bone healing potential. The results show that the addition of HA up to a 200 weight percentage (wt%) relative to collagen content led to significantly increased scaffold stiffness and pore interconnectivity (approximately 10 fold) while achieving a scaffold porosity of 99%. In addition, this biomimetic collagen-HA scaffold exhibited significantly improved bioactivity, in vitro mineralisation after 28 days in culture, and in vivo healing of a critical-sized bone defect. These findings demonstrate the regenerative potential of these biodegradable scaffolds as viable bone graft substitute materials, comprised only of bone's natural constituent materials, and capable of promoting osteogenesis in vitro and in vivo repair of critical-sized bone defects. PMID: 20922667 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Image processing and fractal box counting: user-assisted method for multi-scale porous scaffold characterization. J Mater Sci Mater Med. 2010 Oct 5; Authors: Guarino V, Guaccio A, Netti PA, Ambrosio L Image analysis has gained new effort in the scientific community due to the chance of investigating morphological properties of three dimensional structures starting from their bi-dimensional gray-scale representation. Such ability makes it particularly interesting for tissue engineering (TE) purposes. Indeed, the capability of obtaining and interpreting images of tissue scaffolds, extracting morphological and structural information, is essential to the characterization and design of engineered porous systems. In this work, the traditional image analysis approach has been coupled with a probabilistic based percolation method to outline a general procedure for analysing tissue scaffold SEM micrographs. To this aim a case study constituted by PCL multi-scaled porous scaffolds was adopted. Moreover, the resulting data were compared with the outputs of conventionally used techniques, such as mercury intrusion porosimetry. Results indicate that image processing methods well fit the porosity features of PCL scaffolds, overcoming the limits of the more invasive porosimetry techniques. Also the cut off resolution of such IP methods was discussed. Moreover, the fractal dimension of percolating clusters, within the pore populations, was addressed as a good indication of the interconnection degree of PCL bi-modal scaffolds. Such findings represent (i) the bases for a novel approach complementary to the conventional experimental procedure used for the morphological analysis of TE scaffolds, in particular offering a valid method for the analysis of soft materials (i.e., gels); also (ii) providing a new perspective for further studies integrating to the structural and morphological data, fluid-dynamics and transport properties modelling. PMID: 20922560 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Growth of the chorioallantoic membrane into a rapid-prototyped model pore system: experiments and mathematical model. Biomech Model Mechanobiol. 2010 Oct 5; Authors: Lemon G, Howard D, Yang H, Ratchev SM, Segal JI, Rose FR, Jensen OE, Waters SL, King JR This paper presents a mathematical model to describe the growth of tissue into a rapid-prototyped porous scaffold when it is implanted onto the chorioallantoic membrane (CAM). The scaffold was designed to study the effects of the size and shape of pores on tissue growth into conventional tissue engineering scaffolds, and consists of an array of pores each having a pre-specified shape. The experimental observations revealed that the CAM grows through each pore as an intact layer of tissue, provided the width of the pore exceeds a threshold value. Based on these results a mathematical model is described to simulate the growth of the membrane, assuming that the growth is a function of the local isotropic membrane tension. The model predictions are compared against measurements of the extent of membrane growth through the pores as a function of time for pores with different dimensions. PMID: 20922556 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Scaffolds in tissue engineering of blood vessels. Can J Physiol Pharmacol. 2010 Sep;88(9):855-73 Authors: Pankajakshan D, Agrawal DK Tissue engineering of small diameter (<5 mm) blood vessels is a promising approach for developing viable alternatives to autologous vascular grafts. It involves in vitro seeding of cells onto a scaffold on which the cells attach, proliferate, and differentiate while secreting the components of extracellular matrix that are required for creating the tissue. The scaffold should provide the initial requisite mechanical strength to withstand in vivo hemodynamic forces until vascular smooth muscle cells and fibroblasts reinforce the extracellular matrix of the vessel wall. Hence, the choice of scaffold is crucial for providing guidance cues to the cells to behave in the required manner to produce tissues and organs of the desired shape and size. Several types of scaffolds have been used for the reconstruction of blood vessels. They can be broadly classified as biological scaffolds, decellularized matrices, and polymeric biodegradable scaffolds. This review focuses on the different types of scaffolds that have been designed, developed, and tested for tissue engineering of blood vessels, including use of stem cells in vascular tissue engineering. PMID: 20921972 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | One-step generation of murine embryonic stem cell-derived mesoderm progenitors and chondrocytes in a serum-free monolayer differentiation system. Stem Cell Res. 2010 Sep 6; Authors: Waese EY, Stanford WL Cartilage defects have limited capacity for repair and are often replaced by fibrocartilage with inferior mechanical properties. To overcome the limitations of artificial joint replacement, high-throughput screens (HTS) could be developed to identify molecules that stimulate differentiation and/or proliferation of articular cartilage for drug therapy or tissue engineering. Currently embryonic stem cells (ESCs) can differentiate into articular cartilage by forming aggregates (embryoid body (EB), pellet, micromass), which are difficult to image. We present a novel, single-step method of generating murine ESC-derived chondrocytes in monolayer cultures under chemically defined conditions. Mesoderm induction was achieved in cultures supplemented with BMP4, activin A, or Wnt3a. Prolonged culture with sustained activin A, TGFβ3, or BMP4 supplementation led to robust chondrogenic induction. A short pulse of activin A or BMP4 also induced chondrogenesis efficiently while Wnt3a acted as a later inducer. Long-term supplementation with activin A or with activin A followed by TGFβ3 promoted articular cartilage formation. Thus, we devised a serum-free (SF) culture system to generate ESC-derived chondrocytes without the establishment of 3D cultures or the aid of cell sorting. Cultures were governed by the same signaling pathways as 3D ESC differentiation systems and limb bud mesenchyme or articular cartilage explant cultures. PMID: 20920900 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Structural and material approaches for bone tissue engineering in powder based 3D printing. Acta Biomater. 2010 Oct 1; Authors: Butscher A, Bohner M, Hoffmann S, Gauckler L, Müller R This article aims at reviewing the current state of knowledge concerning the use of powder-based three-dimensional printing (3DP) for the synthesis of bone tissue engineering scaffolds. 3DP is a solid free-form (SFF) technique building up complex open porous 3D structures layer by layer (bottom-up approach). In contrast to traditional fabrication techniques generally subtracting material step by step (top-down approach), SFF approaches allow nearly unlimited designs and large varieties of materials suitable for scaffold engineering. The today's state of the art materials' as well as mechanical and structural requirements for bone scaffolds are summarized and discussed in relation with technical feasibility within 3DP. Advances in the field of 3DP are presented and compared to other SFF methods. Existing strategies on material and design control of scaffolds are reviewed. Finally possibilities and limiting factors are addressed and potential strategies to improve 3DP for scaffold engineering are proposed. PMID: 20920616 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Tissue Engineering Approaches to Enhancing Clinical Islet Transplantation through Tissue Engineeering Strategies. J Diabetes Sci Technol. 2010;4(5):1238-47 Authors: Giraldo JA, Weaver JD, Stabler CL Clinical islet transplantation (CIT), the infusion of allogeneic islets within the liver, has the potential to provide precise and sustainable control of blood glucose levels for the treatment of type 1 diabetes. The success and long-term outcomes of CIT, however, are limited by obstacles such as a nonoptimal transplantation site and severe inflammatory and immunological responses to the transplant. Tissue engineering strategies are poised to combat these challenges. In this review, emerging methods for engineering an optimal islet transplantation site, as well as novel approaches for improving islet cell encapsulation, are discussed. PMID: 20920446 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Importance of interleukin-1 and interleukin-1 receptor antagonist in short-term glucose sensor function in vivo. J Diabetes Sci Technol. 2010;4(5):1073-86 Authors: Klueh U, Liu Z, Feldman B, Kreutzer D BACKGROUND: The importance of the interleukin (IL)-1 cytokine family in inflammation and immunity is well established as a result of extensive in vitro and in vivo studies. In fact, much of our understanding of the in vivo importance of interleukin-1beta (IL-1B) is the result of research utilizing transgenic mice, such as overexpression or deficiencies of the naturally occurring inhibitor of IL-1 known as interleukin-1 receptor antagonist (IL-1RA). For the present studies, we utilized these transgenic mice to determine the role of IL-1B in glucose sensor function in vivo. METHODS: To investigate the role of IL-1B in glucose sensor function in vivo, we compared glucose sensor function in trans-genic mice that (1) overexpressed IL-1RA [B6.Cg-Tg(II1rn)1Dih/J] and (2) are deficient in IL-1RA (B6.129S-Il1rn(tm1Dih)/J), with mice that have normal levels of IL-1RA (C57BL/6). RESULTS: Our studies demonstrated that, during the first 7 days post-sensor implantation (PSI), mice deficient in IL-1RA had extensive inflammation and decreased sensor function when compared to normal or IL-1RA-overexpressing mice. CONCLUSION: These data directly support our hypothesis that the IL-1 family of cytokines and antagonists play a critical role in controlling tissue reactions and thereby sensor function in vivo during the first 7 days PSI. PMID: 20920427 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Bone and cartilage repair using stem cells.] Ugeskr Laeger. 2010 Sep 20;172(38):2616-2619 Authors: Larsen KH, Andersen TE, Kassem M Mesenchymal stem cells (MSC) are capable of multilineage differentiation into cells like osteoblasts, chrondrocytes or adipocytes. MSCs can be isolated from bone marrow and expanded ex vivo for up to 25-40 population doublings while maintaining genetic stability and differentiation potential. MSCs have great potential in the field of tissue engineering and regenerative medicine where cartilage and bone conditions which are non-treatable or show very slow improvement can be effectively handled. Several clinical trials have been performed using MSC and show very promising results. PMID: 20920407 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | In-vitro seeding of human umbilical cord vein endothelial cells on hydroxyapatite for mechanical heart valve applications. J Heart Valve Dis. 2010 Jul;19(4):506-12 Authors: Sha JM, Yan ZY, Cheng GC, Weil XY, Tao YQ, Li YM, Luo L BACKGROUND AND AIM OF THE STUDY: Although heart valve replacement with either a mechanical or biological prosthesis is an effective method to treat valvular heart disease, both approaches have limitations, including thrombus formation, thromboembolism and degeneration problems. The study aim was to demonstrate the in-vitro endothelialization of hydroxyapatite (HAp) to be used as a biomaterial in heart valve prostheses. METHODS: The HAp samples were characterized using X-ray diffractometry to identify the crystalline phase, while the surface morphology of HAp discs was examined using scanning electron microscopy (SEM). Human umbilical vein endothelial cells (HUVECs) were cultured on HAp discs for 1, 3, 5, and 7 days, and on pyrolytic carbon discs for 7 days; cytotoxicity was assessed using the methyl thiazolyl tetrazolium (MTT) assay. The cells were incubated in three groups: (i) an experimental group (cultured with HAp extract); (ii) a negative control (cultured with high-density polyethylene chaff); and (iii) a positive control (culture medium containing 0.1% phenol solution). RESULTS: A morphological examination of the HAp discs revealed the presence of micropores on the disc surface, together with cultured HUVECs. After seven days of culture, the HUVECs began to form a confluent endothelial cell layer covering the HAp discs. There were no visible cells attached to the pyrolytic carbon surface. The MTT assay indicated that HAp did not exert any cytotoxic effect on HUVECs, and low optical density values were obtained in the positive controls. CONCLUSION: The study results showed that HUVECs were able to grow well on HAp discs, and that HAP possessed a good in-vitro bioactivity and biocompatibility towards these cells. Consequently, HAp might be used as a film on mechanical heart valve prostheses, and serve as a promising biomaterial for heart valve replacement. PMID: 20845900 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Human or animal homograft: could they have a future as a biological scaffold for engineered heart valves? J Cardiovasc Surg (Torino). 2010 Jun;51(3):449-56 Authors: Dainese L, Biglioli P Tissue-engineered heart valves (TEHVs) promise to be the ideal heart valve replacement: they have the potential to grow and repair within the host, to minimise inflammatory and immunological responses and to limit thromboembolism. Viable cells included in TEHVs can theoretically adapt to a growing and changing environment exactly as a native biological structure. This could be extremely important in case of paediatric applications, where reoperations are frequently required to replace failed valve substitutes or to accommodate the growth of the patient. At present time the biological matrix from allogenic or xenogenic decellularized valves represents an appropriate valve scaffold in TEHVs, showing theoretically an ability to grow and repair within the host. Viable cells included in extracellular valve matrix can theoretically adapt to a growing and changing environment like the native biological structure. The aim of this paper is to present a review concerning the use of homograft and allograft valves as an ideal substrate for cardiac engineered tissue valves that represent an exciting possibility for in situ regeneration and repair of heart valves. PMID: 20523298 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | [Study on the influence of the configuration of porcine aortic root on the stentless valve design] Zhonghua Wai Ke Za Zhi. 2009 Sep 1;47(17):1336-9 Authors: Wu F, Wei XF, Yi DH, Tan HM, Xu S, Liu WY OBJECTIVE: To provide the reference for the stentless aortic valve design with the study of the inner configuration of porcine aortic root. METHODS: The orifice areas of porcine aortic root at 4 levels (OA1 to 4), the average area of leaflets (Sa), the area analogue of leaflets (AA, AA = 1/2PH), the average area analogue of leaflets (AAa), the value PH of the left, right, non coronary leaflets (PHl, PHr, PHn) and the sums of PHs of the left and non-coronary leaflets (PHln) in the fresh and glutaraldehyde and epichlorohydrin-treated porcine aortic valves (20 respectively) were measured and calculated. The linear correlation and regression analysis by SPSS 12.0 was used to analyze the correlation between Sa and AAa, OA and Sa, OA and AAa, PHl, PHr and PHn, PHln and PHr in both groups. RESULTS: The coefficient correlation between Sa and AAa in fresh and treated groups were 0.886 and 0.872 respectively (P < 0.05). The coefficient correlation between OA1 to 4 and AAa were 0.810, 0.851, 0.900, and 0.815 respectively in fresh group (P < 0.05), and were 0.852, 0.888, 0.836, and 0.817 respectively in treated group (P < 0.05). This showed that the degree of correlation between the average area analogue of leaflets and the average area of leaflets, the orifice areas of aortic root were relatively large. Additionally, the equation of linear regression existed between PHln and PHr in treated group as follows: PHr = -1.665 + 0.688 PHln (r = 0.907, P < 0.05), thereby PHr could be predicted by PHln. CONCLUSION: The value of PH of leaflets could represent the spatial configuration of the aortic root, which provided a referred index for the stentless bioprostheses design. PMID: 20092732 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Frontiers of vascular biology and disease research. Acta Pharmacol Sin. 2010 Oct;31(10):1241-2 Authors: Chen AF, Tang CS PMID: 20921953 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Cancer stem cells from human breast tumors are involved in spontaneous metastases in orthotopic mouse models. Proc Natl Acad Sci U S A. 2010 Oct 4; Authors: Liu H, Patel MR, Prescher JA, Patsialou A, Qian D, Lin J, Wen S, Chang YF, Bachmann MH, Shimono Y, Dalerba P, Adorno M, Lobo N, Bueno J, Dirbas FM, Goswami S, Somlo G, Condeelis J, Contag CH, Gambhir SS, Clarke MF To examine the role of breast cancer stem cells (BCSCs) in metastasis, we generated human-in-mouse breast cancer orthotopic models using patient tumor specimens, labeled with optical reporter fusion genes. These models recapitulate human cancer features not captured with previous models, including spontaneous metastasis in particular, and provide a useful platform for studies of breast tumor initiation and progression. With noninvasive imaging approaches, as few as 10 cells of stably labeled BCSCs could be tracked in vivo, enabling studies of early tumor growth and spontaneous metastasis. These advances in BCSC imaging revealed that CD44(+) cells from both primary tumors and lung metastases are highly enriched for tumor-initiating cells. Our metastatic cancer models, combined with noninvasive imaging techniques, constitute an integrated approach that could be applied to dissect the molecular mechanisms underlying the dissemination of metastatic CSCs (MCSCs) and to explore therapeutic strategies targeting MCSCs in general or to evaluate individual patient tumor cells and predict response to therapy. PMID: 20921380 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | The Wnt signaling pathway in Cellular Proliferation and Differentiation: A tale of two coactivators. Adv Drug Deliv Rev. 2010 Oct 1; Authors: Teo JL, Kahn M Wnt signaling pathways play divergent roles during development, normal homeostasis and disease. The responses that result from the activation of the pathway control both proliferation and differentiation. Tight regulation and controlled coordination of the Wnt signaling cascade is required to maintain the balance between proliferation and differentiation. The non-redundant roles of the coactivator proteins CBP and p300, within the context of Wnt signaling are discussed.We highlight their roles as integrators of the various inputs that a cell receives to elicit the correct and coordinated response. We propose that essentially all cellular information - i.e. from other signaling pathways, nutrient levels, etc. - is funneled down into a choice of coactivators usage, either CBP or p300, by their interacting partner beta-catenin (or catenin-like molecules in the absence of beta-catenin) to make the critical decision to either remain quiescent, or once entering cycle to proliferate without differentiation or to initiate the differentiation process. PMID: 20920541 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Bone and cartilage repair using stem cells.] Ugeskr Laeger. 2010 Sep 20;172(38):2616-2619 Authors: Larsen KH, Andersen TE, Kassem M Mesenchymal stem cells (MSC) are capable of multilineage differentiation into cells like osteoblasts, chrondrocytes or adipocytes. MSCs can be isolated from bone marrow and expanded ex vivo for up to 25-40 population doublings while maintaining genetic stability and differentiation potential. MSCs have great potential in the field of tissue engineering and regenerative medicine where cartilage and bone conditions which are non-treatable or show very slow improvement can be effectively handled. Several clinical trials have been performed using MSC and show very promising results. PMID: 20920407 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [An introduction to stem cell research.] Ugeskr Laeger. 2010 Sep 20;172(38):2594-2597 Authors: Jensen PL, Wegeberg JP, Andersen CY Stem cells (SC) are characterized by the ability of self renewal as well as specialization into different cell types. Stem cells are present in most organs, and can be isolated from adult tissue, embryonic tissue and can be created by a new technology named induced pluripotency. The three types of SC have different potentials in terms of advancing regenerative medicine, but also raise serious safety concerns that need to be addressed before SC can fulfill the expectations by being developed into new cures and treatments for a range of serious cell degenerative diseases. PMID: 20920401 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Evaluation of the osteogenic and chondrogenic differentiation capacities of equine adipose tissue-derived mesenchymal stem cells. Am J Vet Res. 2010 Oct;71(10):1228-36 Authors: Braun J, Hack A, Weis-Klemm M, Conrad S, Treml S, Kohler K, Walliser U, Skutella T, Aicher WK Objective—To evaluate the proliferative behavior, telomere length, immunophenotype, and differentiation capacity of equine adipose tissue-derived mesenchymal stem cells (AT-MSCs). Animals—6 adult racing horses treated for articular Injury but otherwise healthy Procedures—AT-MSCs were Isolated from horses and expanded In Dulbecco modified Eagle medium enriched with fetal bovine serum and antimicrobials. Expression of cell surface antigens and telomere length were Investigated via flow cytometry Differentiation of MSCs Into chondrocytes, osteoblasts, and adipocytes was Induced In vitro by specific stimuli and was evaluated by analyzing marker genes with quantitative reverse transcriptase PCR assays and immunocytochemical and cytologie evaluations. Results—Equine MSCs could be cultured up to the fifth passage before signs of senescence, apoptosis, and detachment Indicated cellular exhaustion. However, the AT-MSCs from 2 of 6 horses survived to later passages with Increased doubling rates and telomere lengths. The cells had a typical phenotype, with expression of CD14, CD73, CD90, CD105, CD140b, and CD164 antigens and a lack of CD34 and CD45 antigens. The cells also had a strong potential to differentiate Into osteoblasts, as characterized by Intense von Kossa and alizarin red staining as well as high Induction of osteopontin. Chondrogenic differentiation was detected via Alelan blue staining and expression of aggrecan and type II collagen Adipogenesis was Induced in AT-MSCs by supplementation of differentiation media with rabbit serum. Conclusions and Clinical Relevance—Equine AT-MSCs representa suitable cellular source for regenerative treatment of bone or cartilage defects, particularly when expanded In vitro for only a few passages. (Am J Vet Res 2010;71:1228-1236). PMID: 20919912 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Engineered Biocompatible Nanoparticles for in Vivo Imaging Applications. J Am Chem Soc. 2010 Oct 4; Authors: Chen S, Wang L, Duce SL, Brown S, Lee S, Melzer A, Cuschieri SA, André P Iron-platinum alloy nanoparticles (FePt NPs) are extremely promising candidates for the next generation of contrast agents for magnetic resonance (MR) diagnostic imaging and MR-guided interventions, including hyperthermic ablation of solid cancers. FePt has high Curie temperature, saturation magnetic moment, magneto-crystalline anisotropy, and chemical stability. We describe the synthesis and characterization of a family of biocompatible FePt NPs suitable for biomedical applications, showing and discussing that FePt NPs can exhibit low cytotoxicity. The importance of engineering the interface of strongly magnetic NPs using a coating allowing free aqueous permeation is demonstrated to be an essential parameter in the design of new generations of diagnostic and therapeutic MRI contrast agents. We report effective cell internalization of FePt NPs and demonstrate that they can be used for cellular imaging and in vivo MRI applications. This opens the way for several future applications of FePt NPs, including regenerative medicine and stem cell therapy in addition to enhanced MR diagnostic imaging. PMID: 20919679 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Modulation of the major histocompatibility complex by neural stem cell-derived neurotrophic factors used for regenerative therapy in a rat model of stroke. J Transl Med. 2010;8:77 Authors: Sun C, Zhang H, Li J, Huang H, Cheng H, Wang Y, Li P, An Y BACKGROUND: The relationship between functional improvements in ischemic rats given a neural stem cell (NSC) transplant and the modulation of the class I major histocompatibility complex (MHC) mediated by NSC-derived neurotrophins was investigated. METHODS: The levels of gene expression of nerve growth factor (NGF), brain-derived neurotropic factor (BDNF) and neurotrophin-3 (NT-3) were assayed from cultures of cortical NSC from Sprague-Dawley rat E16 embryos. The levels of translated NGF in spent culture media from NSC cultures and the cerebral spinal fluid (CSF) of rats with and without NGF injection or NSC transplant were also measured. RESULTS: We found a significant increase of NGF, BDNF and NT-3 transcripts and NGF proteins in both the NSC cultures and the CSF of the rats. The immunochemical staining for MHC in brain sections and the enzyme-linked immunosorbent assay of CSF were carried out in sham-operated rats and rats with surgically induced focal cerebral ischemia. These groups were further divided into animals that did and did not receive NGF administration or NSC transplant into the cisterna magna. Our results show an up-regulation of class I MHC in the ischemic rats with NGF and NSC administration. The extent of caspase-III immunoreactivity was comparable among three arms in the ischemic rats. CONCLUSION: Readouts of somatosensory evoked potential and the trap channel test illustrated improvements in the neurological function of ischemic rats treated with NGF administration and NSC transplant. PMID: 20727165 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
No comments:
Post a Comment