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Cardiac Muscle Cells (cardiac + muscle_cell)
Selected AbstractsExpression and distribution of ZO-3, a tight junction MAGUK protein, in mouse tissuesGENES TO CELLS, Issue 11 2003Akihito Inoko Background:, Three related MAGUK proteins, ZO-1, ZO-2 and ZO-3, are concentrated at the cytoplasmic surface of tight junctions. However, in contrast to ZO-1/ZO-2, our knowledge of the expression and distribution of ZO-3 is still fragmentary, partly due to a lack of antibodies that specifically distinguish ZO-3 from ZO-1 and ZO-2. Results:, We generated one pAb and one mAb that specifically recognized ZO-3 on Western blotting. The immunofluorescence signals obtained with these antibodies completely disappeared from ZO-1/ZO-2-positive tight junctions in the liver of ZO-3-deficient mice, indicating that the antibodies can be used to localize ZO-3 in various tissues by immunofluorescence microscopy. Immunofluorescence microscopy with these antibodies revealed that ZO-3 was concentrated at tight junctions in various types of epithelium, but not in endothelium or at cadherin-based cell-cell adhesion sites (spot adherens junctions of fibroblasts and intercalated discs of cardiac muscle cells), where ZO-1 and ZO-2 are concentrated. Conclusions:, We conclude that ZO-3 is expressed in a more epithelium-specific manner than ZO-1 and ZO-2. These observations provide for a better understanding of the functions of tight junction-associated MAGUKs. [source] Genetically Manipulated Human Skeletal Myoblast Cells for Cardiac TransplantationJOURNAL OF CARDIAC SURGERY, Issue 6 2002Kh H Haider Aim: Considering the promise of skeletal myoblast cell transplantation to improve cardiac function in myocardial myopathies, we aim in the present study to investigate the potential of human skeletal myoblast cells (HSMC) as a carrier for therapeutic genes for the heart muscle. Methods: Skeletal muscle sample is obtained from rectus femoris of the donor and is processed in the tissue culture to generate HSMC by a patented process of Cell Therapy Inc. The HSMC are grown in large 225 mm2 tissue culture flasks coated with collagen for enhanced cell adherence, using patented Super Medium (Cell Therapy Inc., Singapore) containing 10% fetal calf serum, to 80% confluence. The HSMC are passaged at regular time intervals of 48-72 hours to prevent in vitro differentiation. The HSMC thus obtained are transduced three times with retroviral vector carrying Lac-Z reporter gene before transplantation. The Lac-Z transduced HSMC are harvested by trypsinization, washed and re-suspended in serum free Super Medium. Ischemic Porcine model is created by clamping ameroid ring around left circumflex coronary artery in Yorkshire swine, four weeks prior to cell transplantation. For cell transplantation, the animal is anaesthetized, ventilated and heart is exposed by left thoracotomy. Fifteen injections (0.25 ml each) containing 300 million cells are injected in to the left ventricle endocardially under direct vision. For control animal, only culture medium without cells is injected. The animal is euthanized at pre-determined time, heart is explanted and processed for histological examination. The cryosectioning of the tissue and subsequent staining for Lac-Z expression and Hematoxylin-Eosin staining is carried out by standard methods. Results: The skeletal muscle samples processed by the patented method of Cell Therapy yield 85-90% pure HSMC. The preliminary data shows that repeated transductions of myoblast cells with retrovirus carrying Lac-Z yield highly efficient 70-75% Lac-Z positive HSMC population (Figure 1). Dye exclusion test using Trypan blue reveals >95% cell viability at the time of injection. Gross sections of the cardiac tissue stained positive for Lac-Z expression (Figure 2). Histological examination showed the presence of grafted myoblast cells expressing Lac-Z gene in the cardiac tissue (Figure 3). Conclusion: In the light of our preliminary results, we conclude that HSMC may prove to be excellent carriers of transgene for cardiac muscle cells which otherwise are refractory to ordinary gene transfection methods. The use of HSMC mediated gene delivery to cardiac muscle is safer as compared to direct injection of viral vectors in to the heart muscle. Furthermore, the grafted myoblast cells will additionally serve to strengthen the weakened heart muscle. Figure 1.Human Skeletal myoblasts transduced with Lac-Z carrying retrovirus and stained with x-gal. Figure 2.Gross sections of heart muscle stained for Lac-Z expression. Figure 3.X-gal stained porcine heart muscle counter-stained with Eosin. The heart was explanted 6 weeks after transplantation of Lac-Z stained human myoblasts. The arrow shows Lac-Z expressing myoblast cells. [source] Developmental expression and differential cellular localization of obscurin and obscurin-associated kinase in cardiac muscle cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2008Andrei B. Borisov Abstract Obscurin and obscurin-associated kinase are two products of the obscurin transcriptional unit that encodes a recently identified giant muscle-specific protein obscurin. In this study, we characterized the developmental expression and cellular localization of obscurin and obscurin-associated kinase in cardiac muscle cells. We cloned murine obscurin-associated kinase and found that it is abundantly expressed in the heart as two isotypes encoded by 2.2 and 4.9 kb sequences. The 2.2 kb isotype of the kinase was more prominently expressed than the 4.9 kb isotype. Both obscurin and the kinase-like domains were progressively upregulated since the early stages of cardiac development. Obscurin-associated kinase was expressed at higher levels than obscurin at early stages of cardiomyogenesis. Increasing intensity of obscurin expression in the developing heart positively correlated with progressive cell differentiation and was higher in the ventricles compared to the atria. These data were supported by the results of experiments with primary cardiac cell cultures. Obscurin localization changed from a weakly immunopositive diffuse pattern in poorly differentiated cells to an intensely immunolabeled cross-striated distribution at the level of mid-A-bands and Z-disks during the assembly of the myofibrillar contractile apparatus. In dividing myocytes, unlike the interphase cells, obscurin translocated from disassembling myofibrils into a diffuse granulated pattern segregated separately from ,-actinin-immunopositive aggregates. Obscurin-associated kinase was localized mainly to cell nuclei with increasing incorporation into the Z-disks during differentiation. Our results suggest that these two novel proteins are involved in the progression of cardiac myogenesis during the transition to advanced stages of heart development. J. Cell. Biochem. 103: 1621,1635, 2008. © 2007 Wiley-Liss, Inc. [source] Role of MAPK phosphorylation in cytoprotection by pro-vitamin C against oxidative stress-induced injuries in cultured cardiomyoblasts and perfused rat heartJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2003Masahiro Eguchi Abstract The reactive oxygen species (ROS) are known to be generated upon post-ischemic reperfusion (I/R) of the heart, and to injure cardiac muscle cells. The hydrogen peroxide-induced mortality of rat cardiomyoblasts H2c9 was markedly inhibited by previous administration with auto-oxidation-resistant pro-vitamin C, the 2- O -phosphorylated derivative (Asc2P) of ascorbic acid (Asc). The cytoprotection was partially counteracted by an inhibitor of MAPK (mitogen-activated protein kinase) kinase (MEK) as shown by DNA strand cleavage assay and mitochondrial dehydrogenase assay. Immunostains indicated that phosphorylated MAPK increased in the hydrogen peroxide-treated cardiomyoblasts, and that this action was moderately inhibited by Asc2P and restored nearly to the initial, pretreatment level by combined administration of the MEK inhibitor and Asc2P. The I/R-induced cell injuries in perfused rat hearts as estimated by extracellular release of the cardiac enzyme CPK were inhibited by 2- O -,-glucosylascorbic acid (Asc2G) and Asc, whereas the observed cytoprotection for the cardiomyoblasts was partially counteracted by the MEK inhibitor. The increase in phosphorylated MAPK in I/R-operated hearts was moderately inhibited by pro-vitamin C, but restored nearly to the normal non-operated level by combined administration with the MEK inhibitor. This is in contrast to no alteration in levels of non-phosphorylated MAPK for all the cases examined as shown by Western blots, consistent with results of immunostains for the cardiomyoblasts. The inhibitory effect of the MEK inhibitor on MAPK phosphorylation was, therefore, suggested to counteract the cytoprotective effects of pro-vitamin C via a thorough interruption of the phosphorylated MAPK signaling pathway. This was not true of ROS-related events; the scavenging effects of Asc2G and Asc on hydroxyl radicals generated from I/R-operated heart were not affected by combined administration with the MEK inhibitor, as shown by the spin-trapping DMPO-based ESR method. J. Cell. Biochem. 90: 219,226, 2003. © 2003 Wiley-Liss, Inc. [source] Patterning of diverse mammalian cell types in serum free medium with photoablationBIOTECHNOLOGY PROGRESS, Issue 2 2009Vipra Dhir Abstract Integration of living cells with novel microdevices requires the development of innovative technologies for manipulating cells. Chemical surface patterning has been proven as an effective method to control the attachment and growth of diverse cell populations. Patterning polyelectrolyte multilayers through the combination of layer-by-layer self-assembly technique and photolithography offer a simple, versatile, and silicon compatible approach that overcomes chemical surface patterning limitations, such as short-term stability and low-protein adsorption resistance. In this study, direct photolithographic patterning of two types of multilayers, PAA (poly acrylic acid)/PAAm (poly acryl amide) and PAA/PAH (poly allyl amine hydrochloride), were developed to pattern mammalian neuronal, skeletal, and cardiac muscle cells. For all studied cell types, PAA/PAAm multilayers behaved as a cytophobic surface, completely preventing cell attachment. In contrast, PAA/PAH multilayers have shown a cell-selective behavior, promoting the attachment and growth of neuronal cells (embryonic rat hippocampal and NG108-15 cells) to a greater extent, while providing little attachment for neonatal rat cardiac and skeletal muscle cells (C2C12 cell line). PAA/PAAm multilayer cellular patterns have also shown a remarkable protein adsorption resistance. Protein adsorption protocols commonly used for surface treatment in cell culture did not compromise the cell attachment inhibiting feature of the PAA/PAAm multilayer patterns. The combination of polyelectrolyte multilayer patterns with different adsorbed proteins could expand the applicability of this technology to cell types that require specific proteins either on the surface or in the medium for attachment or differentiation, and could not be patterned using the traditional methods. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | ||||||||||