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Microcarrier Culture (microcarrier + culture)
Selected AbstractsEffects of Three-Dimensional Culturing on Osteosarcoma Cells Grown in a Fibrous Matrix: Analyses of Cell Morphology, Cell Cycle, and ApoptosisBIOTECHNOLOGY PROGRESS, Issue 5 2003Chunnuan Chen Osteosarcoma cells were cultured in stirred tank bioreactors with either a fibrous matrix or nonporous microcarriers to study the environmental effects on cell growth, morphology, cell cycle, and apoptosis. Cell cycle and apoptosis were analyzed using flow cytometry and visualized using confocal laser scanning microscopy and fluorescence microscopy. The three-dimensional (3-D) fibrous culture had better cell growth and higher metabolic rates than the two-dimensional (2-D) microcarrier culture because cells in the fibrous matrix were protected from shear stress and had lower apoptosis and cell death even under suboptimal conditions (e.g., nutrient depletion). The polyester fibrous matrix used in this study also exhibited the capability of selectively retaining viable and nonapoptotic cells and disposing apoptotic and nonviable cells. Consequently, very few apoptotic cells were found in the fibrous matrix even in the long-term (1 month) T-flask culture. In the continuous culture with packed fibrous matrixes for cell support, most cells were arrested in the G1/G0 phase after 4 days. Decreasing the dissolved oxygen level from 60 to 10% air saturation did not significantly change cell cycle and apoptosis, which remained low at ,15%. These results could explain why the fibrous bed bioreactor had good long-term stability and was advantageous for production of non-growth-associated proteins by animal cell cultures. [source] Cell proliferation of human bone marrow mesenchymal stem cells on biodegradable microcarriers enhances in vitro differentiation potentialCELL PROLIFERATION, Issue 5 2010L.-Y. Sun Objectives:, For reasons of provision of highly-specific surface area and three-dimensional culture, microcarrier culture (MC) has garnered great interest for its potential to expand anchorage-dependent stem cells. This study utilizes MC for in vitro expansion of human bone marrow mesenchymal stem cells (BMMSCs) and analyses its effects on BMMSC proliferation and differentiation. Materials and methods:, Effects of semi-continuous MC compared to control plate culture (PC) and serial bead-to-bead transfer MC (MC bead-T) on human BMMSCs were investigated. Cell population growth kinetics, cell phenotypes and differentiation potential of cells were assayed. Results:, Maximum cell density and overall fold increase in cell population growth were similar between PCs and MCs with similar starting conditions, but lag period of BMMSC growth differed substantially between the two; moreover, MC cells exhibited reduced granularity and higher CXCR4 expression. Differentiation of BMMSCs into osteogenic and adipogenic lineages was enhanced after 3 days in MC. However, MC bead-T resulted in changes in cell granularity and lower osteogenic and adipogenic differentiation potential. Conclusions:, In comparison to PC, MC supported expansion of BMMSCs in an up-scalable three-dimensional culture system using a semi-continuous process, increasing potential for stem cell homing ability and osteogenic and adipogenic differentiation. [source] Maintenance of pluripotency in mouse embryonic stem cells cultivated in stirred microcarrier culturesBIOTECHNOLOGY PROGRESS, Issue 2 2010Paulo A. N. Marinho Abstract The development of efficient and reproducible culture systems for embryonic stem (ES) cells is an essential pre-requisite for regenerative medicine. Culture scale-up ensuring maintenance of cell pluripotency is a central issue, because large amounts of pluripotent cells must be generated to warrant that differentiated cells deriving thereof are transplanted in great amounts and survive the procedure. This study aimed to develop a robust scalable cell expansion system, using a murine embryonic stem cell line that is feeder-dependent and adapted to serum-free medium, thus representing a more realistic model for human ES cells. We showed that high concentrations of murine ES cells can be obtained in stirred microcarrier-based spinner cultures, with a 10-fold concentration of cells per volume of medium and a 5-fold greater cell concentration per surface area, as compared to static cultures. No differences in terms of pluripotency and differentiation capability were observed between cells grown in traditional static systems and cells that were replated onto the traditional system after being expanded on microcarriers in the stirred system. This was verified by morphological analyses, quantification of cells expressing important pluripotency markers (Oct-4, SSEA-1, and SOX2), karyotype profile, and the ability to form embryoid bodies with similar sizes, and maintaining their intrinsic ability to differentiate into all three germ layers. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Sustained High-Yield Production of Recombinant Proteins in Transiently Transfected COS-7 Cells Grown on Trimethylamine-Coated (Hillex) Microcarrier BeadsBIOTECHNOLOGY PROGRESS, Issue 1 2003Randall N. Knibbs The present study shows that COS-7 cells transiently transfected and maintained on positively charged (trimethylamine-coated) microcarrier beads synthesize recombinant protein at higher levels and for longer periods of time than cells transfected and maintained on polystyrene flasks in monolayer culture. Sustained, high-level synthesis was observed with secreted chimeric proteins (murine E-selectin, and P-selectin-human IgM chimeras) and a secreted hematopoietic growth factor (granulocyte-macrophage colony-stimulating factor). Studies with green fluorescent protein indicated that the transfected cells attached more firmly to the trimethylamine-coated microcarriers than to polystyrene flasks. After 10,14 days in culture, most of the transfected cells detached from the surface of the polystyrene flasks, whereas most transfected cells remained attached to the microcarriers. The transiently transfected microcarrier cultures produced higher levels of protein per transfected cell due to this prolonged attachment. The prolonged attachment and higher output of transfected cells on microcarriers resulted in a 5-fold increase in protein production from a single transfection over two weeks. Thus, microcarrier-based transient transfection yields quantities of recombinant proteins with a significant savings of time and reagents over monolayer culture. [source] |