Animal cell lines

Occasionally, some of the animal cells in short-term cultures do not die, but instead survive indefinitely. These types of animal cell cultures, which can divide indefinitely, are called established cell lines. Established animal cell lines have been obtained from both normal and tumorigenic cells. Immortalized animal cell lines have also been successfully obtained from short-term cultures following their transformation with appropriate oncogenes. 

The physiological significance of the growth requirements for established animal cell lines in serum-free medium is still an unresolved matter. Cultures of... 

Sato, G.H. (1980). Differentiated Animal Cell Lines. Alan R. Liss, New York. 

Many of the initial biopharmaceuticals approved were simple replacement proteins (e.g. blood factors and human insulin). The ability to alter the amino acid sequence of a protein logically coupled to an increased understanding of the relationship between protein structure and function (Chapters 2 and 3) has facilitated the more recent introduction of several engineered therapeutic proteins (Table 1.3). Thus far, the vast majority of approved recombinant proteins have been produced in the bacterium E. coli, the yeast S. cerevisiae or in animal cell lines (most notably Chinese hamster ovary (CHO) cells or baby hamster kidney (BHK) cells. These production systems are discussed in Chapter 5. 

The biopharmaceutical sector is largely based upon the application of techniques of molecular biology and genetic engineering for the manipulation and production of therapeutic macromolecules. The majority of approved biopharmaceuticals (described from Chapter 8 onwards) are proteins produced in engineered cell lines by recombinant means. Examples include the production of insulin in recombinant E. coli and recombinant S. cerevisiae, as well as the production of EPO in an engineered (Chinese hamster ovary) animal cell line. 

The desired gene/cDNA is normally amplified, sequenced and then introduced into an expression vector that facilitates its introduction and expression (transcription and translation) in an appropriate producer cell type. All recombinant therapeutic proteins approved to date are produced in E. coli, S. cerevisiae or in animal cell lines (mainly CHO or BHK cells). The general... 

Technical advances facilitating genetic manipulation of animal cells now allow routine production of therapeutic proteins in such systems. The major advantage of these systems is their ability to carry out post-translational modification of the protein product. As a result, many biopharmaceuticals that are naturally glycosylated are now produced in animal cell lines. CHO and BHK cells have become particularly popular in this regard. 

Bioassays of related substances can be quite similar in design. Specific growth factors, for example, stimulate the accelerated growth of specific animal cell lines. Relevant bioassays can be undertaken by incubation of the growth-factor-containing sample with a culture of the relevant sensitive cells and radiolabelled nucleotide precursors. After an appropriate time period, the level of radioactivity incorporated into the DNA of the cells is measured. This is a measure of the bioactivity of the growth factor. 

Viral vector manufacture for therapeutic purposes involves initial viral propagation in appropriate animal cell lines, viral recovery, concentration, purification and formulation. A generalized manufacturing scenario for adenoviral-based vectors is outlined in Figure 14.7. The manufacture of alternative viral vectors likely follows a substantially similar approach. 

Master and working banks of both the viral vector and the animal cell line will have been constructed during the drug development process (see Chapter 4). Manufacture of a batch of vector, therefore, will be initiated by the culture of packing cells in suitable animal cell bioreactors. The... 

The second paper goes more into the hardware and programming needed for control loops in a production setting. Four fermentation models are used for this portion E. coli (unicellular), S. fradiae (filamentous), Pichia pastoris (unicellular), and CHO-K1 (animal cell line). Fermentation profiles are shown and strategies are discussed. 

Animal Cell Lines Species, strains, breeding conditions, tissue or organ of origin, geographical origin, age, sex and general physiological conditions. 

Like any other animal cell line, insect cells have a great number of nutrient requirements for cell growth in vitro. These include a carbon source such as glu-... 

Antibiotics are required to prevent microbial growth consequent to accidental microbial contamination. Supplemental serum (often bovine or fetal calf serum, or synthetic serum composed of a mixture of growth factors, hormones and metabolites typically found in serum) is required as a source of the often ill-defined growth factors required by some animal cell lines. 

The functional effects of glycosylation take on added significance in the context of producing gonadotrophins by recombinant means. As subsequently discussed, several are now produced for clinical application in recombinant (animal cell line) systems. While the glycosylation patterns observed on the recombinant molecules can vary somewhat in composition from those associated with the native hormone, these slight differences bear no negative influence upon their clinical applicability. 

Recombinate (rhFactor VIII produced in an animal cell line) Baxter Healthcare/ Haemophilia A Genetics Institute 1992 (USA)... 

The animal cell lines mentioned above are more extensively discussed in Chapters 2, 17,18, 20, and 21. 

Various animal cell lines can be cultivated in vitro, such as cardiac cells, fibroblasts, smooth muscle cells, endocrine cells (such as pituitary, adrenal, and pancreatic cells), epithelial cells (such as liver, mammary, lung, and kidney cells), tumor cells (such as melanocytes), nervous system cells (such... 

In vitro/ex vivo mitogenicity in human cell lines or animal cell lines (expressing receptor or transfected with human receptor)... 

Ohno T Takeuchi M (1990) Test for mycoplasma contamination. Standardized protocols for quality control of animal cell lines. Report from JTCA Cell Bank Committee, Tissue Culture Research Communications 9 Suppl. 9-11. 

Despite the high social relevance of infectious diseases and widespread use of animal cell lines in vaccine production, the application of even unstructured models for quantitative analysis and parameter estimation has not been common practice in bioprocess optimization. So far, research concerning influenza vaccine production in MDCK cell cultures has focused on the characterization of metabolism, growth of different cell lines and virus yields in various production systems [1,2]. 

Busulfan has been shown to induce gene mutations and chromosomal damage in bacteria, fungi, plant species. Drosophila, and in animal cell lines in culture. Busulfan does not require S9 activation in in vitro toxicity assays. 

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