Optimization of cell culture conditions for production of biologically active proteins

Abstract

We investigated the basic technology of cell culture conditions for production of useful substances such as cytokines, and related proteins produced by Namalwa cells. Namalwa cells (Klein, 1972), human B lymphoblastoid cells, were used for large scale production of alpha-interferon (Klein, 1979). Namalwa KJM-1, a subline of Namalwa cells, adapted to serum- and albumin-free medium, can grow at a high density above 1 x 10(7) cells/ml in suspension mode by the use of a perfusion culture system, Biofermenter, containing a cone-type cell-sedimentation column as cell separator (Sato, 1983). Several kinds of cytokine cDNA can be introduced and expressed in Namalwa KJM-1 cells (Miyaji, 1990a,b,c). Some of these were produced in large quantities by use of a gene amplification method with dhfr (Miyaji, 1990c), even though the Namalwa KJM-1 cells contained endogenous dhfr genes. For stable production of the target protein, Namalwa KJM-1 cells are very useful host cells, because they have no effective endogenous protease activity in the conditioned medium. Using Biofermenter with micro-silicone fibers and a dialysis system, the specific productivity of the target proteins was not depressed at a high cell density.

Erythropoietin and Cancer: The Unintended Consequences of Anemia Correction

“…During post-translation modification, the N-terminal 24-amino acid signal peptide is cleaved and the protein is modified by glycosylation, phosphorylation, and ubiquitination to a mature 66–105 kDa protein (38, 44, 45). Mature human receptor consists of extracellular, single transmembrane, and cytoplasmic regions (46) (Figure 1).…”

Development of a suspension packaging cell line for production of high titre, serum-resistant murine leukemia virus vectors

“…For example, bulk production of viral vaccines is currently obtained by suspension cultures grown in large volumes and at high cell density by the use of perfusionreactors and fermenters. 20,21 In this study, a T-lymphoblastoid and a B-lymphoblastoid cell line were tested for their ability to produce MLV particles. A suspension amphotropic packaging cell line that produces high-titre, serum-resistant virus vectors was established and partially characterised in terms of optimum vector production and evaluated for cell growth and viral vector production.…”

Microarray platform affords improved product analysis in mammalian cell growth studies

“…Media development has been used to optimize CHO cell growth and/or the transgene expression in bioprocesses [14-17]. Media components such as carbon source, nitrogen sources, copper sulfate, manganese sulfate, and zinc sulfate and bioreactor temperature, pH, and shear stress can also impact cell growth, productivity and post-translational modifications of the transgenic protein produced [2, 17-23].…”

“…Media components such as carbon source, nitrogen sources, copper sulfate, manganese sulfate, and zinc sulfate and bioreactor temperature, pH, and shear stress can also impact cell growth, productivity and post-translational modifications of the transgenic protein produced [2, 17-23]. There are two strategies to increase productivity in cell lines with media optimization (1) increase specific productivity (i.e., amount of recombinant monoclonal antibody produced per cell of a bioreactor/day) and (2) increase cell yield (i.e., the total integrated viable cell density (IVCD) for the culture duration).…”