Mammalian cell cultures are the preferred expression systems for the production of biopharmaceuticals requiring posttranslational processing. Usually, cell cultures are cultivated in medium supplemented with serum, which supports cell proliferation, viability, and productivity. However, due to scientific and regulatory concerns, serum-free conditions are required in recombinant protein producti...

Fringe modulates Notch signaling resulting in the establishment of compartmental boundaries in developing organisms. Fringe is a beta 3N-acetylglucosaminyltransferase (beta 3GlcNAcT) that transfers GlcNAc to O-fucose in epidermal growth factor-like repeats of Notch. Here we use five different Chinese hamster ovary cell glycosylation mutants to identify a key aspect of the mechanism of fringe ac...

Dopamine and to a much greater extent, 6-hydroxydopamine reduced the growth of the mouse neuroblastoma cell population in vitro but did not induce morphological differentiation. The growth inhibition at a lower drug concentration was primarily due to inhibition of cell multiplication, which was reversible. L-Dopa, norepinephrine, epinephrine, 3,4-dihydroxyphenylacetic acid, or homovanillic acid...

A new approach using microtiter plate cultivation with on-line measurement of dissolved oxygen (DO) was applied for medium optimization of mammalian cell culture. Applying dynamic liquid phase balance, oxygen uptake rates were calculated from the DO level and used as an indicator for culture viability. The developed method was successfully applied to optimization of the concentration of glucose...

Dopamine and to a much greater extent, 6-hydroxydopamine reduced the growth of the mouse neuroblastoma cell population in vitro but did not induce morphological differentiation. The growth inhibition at a lower drug concentration was primarily due to inhibition of cell multiplication, which was reversible. L-Dopa, norepinephrine, epinephrine, 3,4-dihydroxyphenylacetic acid, or homovanillic acid...

Biopharmaceutical proteins are usually produced by culturing recombinant Chinese hamster ovary (CHO) cells. High producer cell lines screened from transfected cells with random integration of target genes. Since transgene expression is susceptible to the surrounding environment integrated genomic locus, should be selected a large number heterogeneous insertion. In contrast, targeted into charac...

Hypoxia and an acidic environment are known to occur in regions of solid tumors and might be involved in the causation of necrosis. The viability and energy metabolism of cells in tissue culture were therefore investigated under hypoxic and/or acidic conditions. Acute exposure of Chinese hamster ovary (CHO) cells or human bladder cancer MGH-U1 cells to hypoxia plus low pH (6.5 to 6.0) was cytot...

In using a monoclonal antibody against a major cytoplasmic protein of 46,000 mol wt, we have characterized an intermediate-sized (10 nm) filamentous cytoskeleton in Drosophila melanogaster tissue culture cells. Indirect immunofluorescence, immunoelectron microscopy, and protein blotting show that this cytoskeleton exhibits features typical of the vertebrate vimentin cytoskeleton, including the ...

In the present article, we describe a 3-day experimental workshop on glycemia regulation and type 1 diabetes that engages students in open-ended investigations and guided experiments leading to results that are not already known to them. After an initial questioning phase during which students observe PowerPoint slides depicting the glycemia (blood glucose levels) of individuals in various situ...