|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | The Role of Cardiac Electrophysiology in Myocardial Regenerative Stem Cell Therapy. J Cardiovasc Transl Res. 2010 Dec 3; Authors: Huang G, Pashmforoush M, Chung B, Saxon LA Recent advances in stem cell biology and tissue engineering have put forth new therapeutic paradigms for treatment of myocardial disease. The aim of stem cell therapy for myocardial regeneration has been directed to induce angiogenesis for ischemic heart disease and/or introduction of new cardiomyocytes to improve the mechanical function of the failing heart. Encouraged by positive preliminary results in mouse models of myocardial infarction, clinical trials have utilized autologous skeletal myoblasts and bone-marrow-derived stem cells to treat patients in various clinical settings including acute myocardial injury, chronic angina, and heart failure [1-3]. These studies have collectively shown, at best, modest improvement in cardiac function. This may be due to the fact that there is little evidence to support actual formation and/or integration of transplanted cells into the recipient myocardium. More recent and emerging data supports the finding that electrical stimulation may be an effective catalyst for sustained functional organization, integration, and maturation of transplanted cell populations into the host myocardium. A therapeutic model that utilizes electrical stimulation and/or achieves cardiac resynchronization in conjunction with stem cell transplantation may be an effective means to achieve successful myocardial regenerative therapy. PMID: 21128127 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Preservation of the cardiac function in infarcted rat hearts by the transplantation of adipose-derived stem cells with injectable fibrin scaffolds. Exp Biol Med (Maywood). 2010 Dec 1;235(12):1505-15 Authors: Zhang X, Wang H, Ma X, Adila A, Wang B, Liu F, Chen B, Wang C, Ma Y Cell-based therapy can improve cardiac function but is limited by the low cell retention and survival within ischemic tissues. Injectable cardiac tissue engineering aims to support cell-based therapies and enhance their efficacy for cardiac diseases. So far, no research has been devoted to studying the usefulness of the combination of fibrin glue (as scaffold) and adipose-derived stem cells (ADSCs) to treat myocardial infarction. In our study, the rat ADSCs were isolated from subcutaneous adipose tissues. The surface phenotype of these cells was analyzed by flow cytometry. The fibrin glue was then co-injected with ADSCs into the left ventricular wall of rat infarction models. The structure and functional consequences of transplantation were determined by detailed histological analysis and echocardiography. Most cultured ADSCs expressed CD105 and CD90, and were negative for CD34 and CD45. After injection, both the 24-h cell retention and four-week graft size were significantly higher and larger in the Fibrin + ADSCs group than those of the ADSCs group alone (P < 0.01). The heart function improved significantly in the Fibrin + ADSCs group compared with that of the ADSCs group four weeks after transplantation (P < 0.01). In addition, the arteriole densities within the infarcted area improved significantly in the Fibrin + ADSCs group compared with those in the ADSCs group four weeks after transplantation (P < 0.01). In conclusion, the ADSCs with the fibrin glue has the therapeutic potential to improve the function of infarcted hearts. The method of in situ injectable tissue engineering combining fibrin glue with ADSCs is promising clinically. PMID: 21127347 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Treatment of meniscal injury: a current concept review. Chin J Traumatol. 2010 Dec 1;13(6):370-6 Authors: Gu YL, Wang YB Meniscal injury is one of the most common injuries to the knee. The menisci are important for normal knee function. And loss of a meniscus increases the risk of subsequent development of degenerative changes in the knee. Now there are different techniques available for meniscal injury. These techniques include expectant treatment, meniscectomy, meniscal repair, meniscal replacement, and meniscal tissue engineering. Expectant treatment is the appropriate treatment for minor tears of the menisci. Meniscectomy being favored at the beginning is now obsolete. Meniscus repair has become a standard procedure. Meniscal replacement and tissue engineering are used to deal with considerable meniscal injuries. The purpose of this paper is to provide current knowledge regarding the anatomy and function of the menisci, incidence, aetiology, symptoms, signs, investigations and treatments of meniscal injury. PMID: 21126396 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Murine embryonic stem cells self renewal and pluripotency is maintained by a bovine granulosa cell line conditioned medium while increasing the proliferation rate. Stem Cells Dev. 2010 Dec 2; Authors: Losino N, Luzzani C, Solari C, Boffi J, Louis Tisserand M, Sevlever G, Barañao L, Guberman A Murine embryonic stem cells (mESCs) are pluripotent cells that can be propagated in an undifferentiated state in continuous culture on a feeder layer or without feeders in the presence of leukemia inhibitory factor (LIF). Although there has been a great advance since their establishment, ESC culture is still complex and expensive. Therefore, finding culture conditions that maintain self renewal of ES cells, preventing their differentiation and promoting their proliferation is still an area of great interest. In this work, we studied the effects of the conditioned medium from a bovine granulosa cell line (BGC-CM), on the maintenance of self renewal and pluripotency of mESCs. We found that this medium is able to maintain mESC self renewal while preserving its critical properties without LIF addition. mESC cultured in BGC-CM expressed the stem cell markers Oct4, Sox2, Nanog, SSEA-1, Klf4, Rex1, and ECAT1. Moreover, mESC cultured in BGC-CM gave rise to embryoid bodies and teratomas that differentiated effectively to diverse cell populations from endoderm, mesoderm and ectoderm. Furthermore, we found that mESC cultured in BGC-CM have an increased proliferation rate compared with cells grown in mESC standard culture medium supplemented with LIF. These findings may provide a powerful tool to culture mESC for long periods of time with high proliferation rate, while preserving its basic characteristics, contributing to the application of these cells to assess potential tissue engineering and cellular therapy applications. PMID: 21126164 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Bioactive collagen-grafted poly-L-lactic acid nanofibrous membrane for cartilage tissue engineering. J Nanosci Nanotechnol. 2010 Aug;10(8):5393-8 Authors: Chen JP, Li SF, Chiang YP Biodegradable nanofibrous membrane was prepared from poly-L-lactic acid by electrospinning and used as a scaffold for cartilage tissue engineering. Operating parameters during the electrospinning process were studied in terms of their influences on fiber diameter, membrane porosity and pore size. In order to improve cell attachment and growth, nanofibrous membrane was subject to DC-pulsed oxygen plasma treatment, followed by acrylic acid grafting and collagen coating by covalent binding of collagen to carboxylic moieties of the polyacrylic acid. The membrane was fully characterized for its physical and chemical properties. Primary chondrocyte cells seeded into the membrane proliferated well and maintain high viability within the membrane from Confocal Laser Scanning Microscopy. Cell differentiation was confirmed by secretion of glycoaminoglycan and collagen during the cultivation period. Scanning electron microscope observation of the cell-scaffold construct confirms the tight attachment of cells to nanofibers and in-growth of cells into the interior of the membrane with proper maintenance of morphology and structure of chondrocytes. PMID: 21125905 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | The use of zein and Shuanghuangbu for periodontal tissue engineering. Int J Oral Sci. 2010 Sep;2(3):142-8 Authors: Yan-Zhi X, Jing-Jing W, Chen YP, Liu J, Li N, Yang FY AIM: Tissue engineering is a promising area with a broad range of applications in the fields of regenerative medicine and human health. The emergence of periodontal tissue engineering for clinical treatment of periodontal disease has opened a new therapeutic avenue. The choice of scaffold is crucial. This study was conducted to prepare zein scaffold and explore the suitability of zein and Shuanghuangbu for periodontal tissue engineering. METHODOLOGY: A zein scaffold was made using the solvent casting/particulate leaching method with sodium chloride (NaCl) particles as the porogen. The physical properties of the zein scaffold were evaluated by observing its shape and determining its pore structure and porosity. Cytotoxicity testing of the scaffold was carried out via in vitro cell culture experiments, including a liquid extraction experiment and the direct contact assay. Also, the Chinese medicine Shuanghuangbu, as a growth factor, was diluted by scaffold extract into different concentrations. This Shuanghuangbu-scaffold extract was then added to periodontal ligament cells (PDLCs) in order to determine its effect on cell proliferation. RESULTS: The zein scaffold displayed a sponge-like structure with a high porosity and sufficient thickness. The porosity and pore size of the zein scaffold can be controlled by changing the porogen particles dosage and size. The porosity was up to 64.1%-78.0%. The pores were well-distributed, interconnected, and porous. The toxicity of the zein scaffold was graded as 0-1. Furthermore, PDLCs displayed full stretching and vigorous growth under scanning electronic microscope (SEM). Shuanghuangbu-scaffold extract could reinforce proliferation activity of PDLCs compared to the control group, especially at 100 microg x mL(-1) (P < 0.01). CONCLUSION: A zein scaffold with high porosity, open pore wall structure, and good biocompatibility is conducive to the growth of PDLCs. Zein could be used as scaffold to repair periodontal tissue defects. Also, Shuanghuangbu-scaffold extract can enhance the proliferation activity of PDLCs. Altogether, these findings provide the basis for in vivo testing on animals. PMID: 21125792 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Clonal characterization of bone marrow derived stem cells and their application for bone regeneration. Int J Oral Sci. 2010 Sep;2(3):127-35 Authors: Xiao Y, Mareddy S, Crawford R Tissue engineering allows the design of functionally active cells within supportive bio-scaffolds to promote the development of new tissues such as cartilage and bone for the restoration of pathologically altered tissues. However, all bone tissue engineering applications are limited by a shortage of stem cells. The adult bone marrow stroma contains a subset of nonhematopoietic cells referred to as bone marrow mesenchymal stem cells (BMSCs). BMSCs are of interest because they are easily isolated from a small aspirate of bone marrow and readily generate single-cell-derived colonies. These cells have the capacity to undergo extensive replication in an undifferentiated state ex vivo. In addition, BMSCs have the potential to develop either in vitro or in vivo into distinct mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Thus, BMSCs are an attractive cell source for tissue engineering approaches. However, BMSCs are not homogeneous and the quantity of stem cells decreases in the bone marrow in aged population. A sequential loss of lineage differentiation potential has been found in the mixed culture of bone marrow stromal cells due to a heterogenous population. Therefore, a number of studies have proposed that homogenous bone marrow stem cells can be generated from clonal culture of bone marrow cells and that BMSC clones have the greatest potential for the application of bone regeneration in vivo. PMID: 21125790 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Acidic stress promotes a glioma stem cell phenotype. Cell Death Differ. 2010 Dec 3; Authors: Hjelmeland AB, Wu Q, Heddleston JM, Choudhary GS, Macswords J, Lathia JD, McLendon R, Lindner D, Sloan A, Rich JN Malignant gliomas are lethal cancers that display cellular hierarchies with cancer stem cells at the apex. Glioma stem cells (GSCs) are not uniformly distributed, but rather located in specialized niches, suggesting that the cancer stem cell phenotype is regulated by the tumor microenvironment. Indeed, recent studies show that hypoxia and its molecular responses regulate cancer stem cell maintenance. We now demonstrate that acidic conditions, independent of restricted oxygen, promote the expression of GSC markers, self-renewal and tumor growth. GSCs exert paracrine effects on tumor growth through elaboration of angiogenic factors, and low pH conditions augment this expression associated with induction of hypoxia inducible factor 2α (HIF2α), a GSC-specific regulator. Induction of HIF2α and other GSC markers by acidic stress can be reverted by elevating pH in vitro, suggesting that raising intratumoral pH may be beneficial for targeting the GSC phenotype. Together, our results suggest that exposure to low pH promotes malignancy through the induction of a cancer stem cell phenotype, and that culturing cancer cells at lower pH reflective of endogenous tumor conditions may better retain the cellular heterogeneity found in tumors.Cell Death and Differentiation advance online publication, 3 December 2010; doi:10.1038/cdd.2010.150. PMID: 21127501 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Endothelial progenitor cells as therapeutic agents in the microcirculation: An update. Atherosclerosis. 2010 Nov 3; Authors: Napoli C, Hayashi T, Cacciatore F, Casamassimi A, Casini C, Al-Omran M, Ignarro LJ This review evaluates novel beneficial effects of circulating endothelial progenitor cells (EPCs) as shown by several preclinical studies and clinical trials carried out to test the safety and feasibility of using EPCs. There are 31 registered clinical trials (and many others still ongoing) and 19 published studies. EPCs originate in the bone marrow and migrate into the bloodstream where they undergo a differentiation program leading to major changes in their antigenic characteristics. EPCs lose typical progenitor markers and acquire endothelial markers, and two important receptors, (VEGFR and CXCR-4), which recruit circulating EPCs to damaged or ischemic microcirculatory (homing to damaged tissues) beds. Overall, therapeutic angiogenesis will likely change the face of regenerative medicine in the next decade with many patients worldwide predicted to benefit from these treatments. PMID: 21126740 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Encapsulation of BMP2 with Cbfa1-overexpressing osteogenic cells derived from human embryonic stem cells in hydrogel accelerates bone tissue regeneration. Stem Cells Dev. 2010 Dec 2; Authors: Kim MJ, Park JS, Kim S, Moon SH, Yang HN, Park KH, Chung HM Bone tissue defects caused by trauma and disease are significant problems in orthopedic surgery. Human embryonic stem cells (hESCs) hold great promise for the treatment of bone tissue disease in regenerative medicine. In this study, we have established an effective method for the differentiation of osteogenic cells derived from hESCs using a lentiviral vector containing the transcription factor Cbfa1. Differentiation was initiated in embryoid body (EB) formation of Cbfa1-expressing hESC, resulting in a highly purified population of osteogenic cells based on flow cytometric analysis. These cells also showed characteristics of osteogenic cells in vitro, as determined by RT-PCR analysis and immunocytochemistry using osteoblast-specific markers. We also evaluated the regenerative potential of Cbfa1-expressing cells derived from hESCs (hESC-CECs) compared to hESCs and the osteogenic effects of bone morphogenic protein-2 (BMP2) encapsulated in thermo-reversible hydrogel in vivo. hESC-CECs were embedded in hydrogel constructs enriched with BMP2 to promote bone regeneration. We observed prominent mineralization and the formation of nodule-like structures using von Kossa and Alizarin red S staining. In addition, the expression patterns of osteoblast-specific genes were verified by RT-PCR, and immunohistochemical analysis revealed that collagen type 1 (COL1) and Cbfa1 were highly expressed in hESC-CECs compared to other cell types. Taken together, our results suggest that encapsulation of hESC-CECs with BMP-2 in hydrogel constructs appears to be a promising method to enhance the in vitro osteoblastic differentiation and in vivo osteogenic activity of hESC-CECs. PMID: 21126165 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | The use of zein and Shuanghuangbu for periodontal tissue engineering. Int J Oral Sci. 2010 Sep;2(3):142-8 Authors: Yan-Zhi X, Jing-Jing W, Chen YP, Liu J, Li N, Yang FY AIM: Tissue engineering is a promising area with a broad range of applications in the fields of regenerative medicine and human health. The emergence of periodontal tissue engineering for clinical treatment of periodontal disease has opened a new therapeutic avenue. The choice of scaffold is crucial. This study was conducted to prepare zein scaffold and explore the suitability of zein and Shuanghuangbu for periodontal tissue engineering. METHODOLOGY: A zein scaffold was made using the solvent casting/particulate leaching method with sodium chloride (NaCl) particles as the porogen. The physical properties of the zein scaffold were evaluated by observing its shape and determining its pore structure and porosity. Cytotoxicity testing of the scaffold was carried out via in vitro cell culture experiments, including a liquid extraction experiment and the direct contact assay. Also, the Chinese medicine Shuanghuangbu, as a growth factor, was diluted by scaffold extract into different concentrations. This Shuanghuangbu-scaffold extract was then added to periodontal ligament cells (PDLCs) in order to determine its effect on cell proliferation. RESULTS: The zein scaffold displayed a sponge-like structure with a high porosity and sufficient thickness. The porosity and pore size of the zein scaffold can be controlled by changing the porogen particles dosage and size. The porosity was up to 64.1%-78.0%. The pores were well-distributed, interconnected, and porous. The toxicity of the zein scaffold was graded as 0-1. Furthermore, PDLCs displayed full stretching and vigorous growth under scanning electronic microscope (SEM). Shuanghuangbu-scaffold extract could reinforce proliferation activity of PDLCs compared to the control group, especially at 100 microg x mL(-1) (P < 0.01). CONCLUSION: A zein scaffold with high porosity, open pore wall structure, and good biocompatibility is conducive to the growth of PDLCs. Zein could be used as scaffold to repair periodontal tissue defects. Also, Shuanghuangbu-scaffold extract can enhance the proliferation activity of PDLCs. Altogether, these findings provide the basis for in vivo testing on animals. PMID: 21125792 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Biologic scaffolds for constructive tissue remodeling. Biomaterials. 2011 Jan;32(1):316-9 Authors: Badylak SF, Brown BN, Gilbert TW, Daly KA, Huber A, Turner NJ PMID: 21125721 [PubMed - in process] | | | | | | | | | |  | |  | |  |
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