Peptones are protein digests composed mainly of amino acids and small peptides. Peptones have been used in mammalian cell culture medium as a serum substitute to enhance cell growth and product formation. The first part of this study describes our evaluation of peptones from different sources (soy, wheat, yeast, and casein) on the cell growth and productivity of Sp2/0 myeloma cells expressing recombinant prourokinase (r-ProUK). The results of these studies demonstrated that wheat peptone was the most effective plant peptone to increase r-ProUK yield. Addition of 2 g/L wheat peptone to the culture medium increased batch r-ProUK production between 28-67% compared to cells grown in the absence of peptone supplements. Peptones did not increase cell productivity, but increases r-ProUK yield through increased culture longevity…
Tag: <span>mammalian cell culture</span>
Glycosylation, a posttranslational modification that adds sugars to proteins, is required by many proteins to function properly. Glycosylation can modulate the biological activities of monoclonal antibodies (MAbs), including certain effector functions in the Fc region of IgG antibodies. Monoclonal antibodies produced at higher expression levels by mammalian cell culture may contain small amounts of nonglycosylated heavy chain (NGHC). Recent cell culture mini-reactor studies have shed light on the process parameters that most affect the occurrence of NGHC, and have greatly minimized NGHC levels in IgG MAb products…
The K562 cell line is a human myelogenous leukemic cell which has been used by several groups, including ours, as a vehicle for cell-based vaccines and immuno-gene therapies. The attractiveness of K562 cells is the ease with which they can be cultured, plus the fact that they express very low levels of MHC proteins. Low MHC expression facilitates the use of these cells in patients with different MHC backgrounds, and it may improve the in vivo survival of the cells by delaying immune rejection. Based largely on these properties, we have been developing the K562 cell line as a universal platform for expressing cytokines, tumor antigens, and other immuno-modulating proteins…
Growth media for mammalian cell culture are complex mixtures of raw materials that include amino acids, vitamins, inorganic salts and a wide variety of other components. The risk of infectious agent transmission, when some of these components are derived directly from animals, is a major concern in the biopharmaceutical industry, and is being actively addressed. However, the risk associated with the use of indirectly, or secondarily, derived animal components is less recognized and addressed. We have developed a classification system to define the contact level that a cell culture medium component has had with animal-derived materials. This classification system has increased the accuracy and reliability of the information we are able to obtain from raw material manufacturers, and is being used as part of a risk assessment analysis for a serum/protein-free media we are moving from development into manufacturing…
Apoptosis is an essential biological process that has been conserved among eukaryotic organisms throughout evolution. Apoptosis, or programmed cell death, is necessary for embryological development, tissue homeostasis, immune system maintenance and development, and as a defense mechanism against the progression of cancer and viral infection. With the advent of biotechnology and the development of associated molecular biology techniques such as recombinant DNA technology and mammalian cell culture, tissues can be extracted from organisms and have their cells cultured as single cell suspensions or adherent monolayers. Therefore, these cultures can function as living production facilities for antibodies, recombinant glycoproteins, vaccines, hormones, growth factors, and more. However, the cell’s ability to control its own death is not lost upon its manipulation from the organism to culture. Consequently, apoptosis, which is so fundamentally important in-vivo, becomes a detriment to biochemical manufacturers in-vitro…