Nutrients cell growth

Nutritional Requirements. The nutrient requirements of mammalian cells are many, varied, and complex. In addition to typical metaboHc requirements such as sugars, amino acids (qv), vitamins (qv), and minerals, cells also need growth factors and other proteins. Some of the proteins are not consumed, but play a catalytic role in the cell growth process. Historically, fetal calf semm of 1—20 vol % of the medium has been used as a rich source of all these complex protein requirements. However, the composition of semm varies from lot to lot, introducing significant variabiUty in manufacture of products from the mammalian cells. 

Biomass or mass of living matter, living cells in a liquid solution with essential nutrients at suitable temperature and pH leads to cell growth. As a result, the content of biomass increases with time. 

Somatostatin acts on various organs, tissues and cells as neurotransmitter, paracrine/autocrine and endocrine regulator on cell secretion, smooth muscle contractility, nutrient absorption, cell growth and neurotransmission [1]. Some of its mainly inhibitory effects are listed in Table 1. Somatostatin mediates its function via a family of heptahelical G-protein-coupled receptors termed... 

Continuous Stirred Tanks with Biomass Recycle. When the desired product is excreted, closing the system with respect to biomass offers a substantial reduction in the cost of nutrients. The idea is to force the cells into a sustained stationary or maintenance period where there is relatively little substrate used to grow biomass and where production of the desired product is maximized. One approach is to withhold some key nutrient so that cell growth is restricted, but to supply a carbon source and other components needed for the desired product. It is sometimes possible to maintain this state for weeks or months and to achieve high-volumetric productivities. There will be spontaneous cell loss (i.e., kd > 0), and true steady-state operation requires continuous purging and makeup. The purge can be achieved by incomplete separation and recycle... 

Only two decades ago researchers started to study the effect of nutrient concentration on cell growth and metabolism systematically and the effect of pro-... 

Borowitzka, M.A., Huisman, J.M., and Osborn, A., Culture of the astaxanthin-pro-ducing green alga Haematococcus pluvialis. I. Effects of nutrients on growth and cell type, J. Appl Phycol, 3, 295, 1991. 

Nutrients—Nutrients, such as nitrogen and phosphorus and other trace elements, are necessary for cell growth because they are key biological building blocks.52,53 Addition of nutrients as a supplement helps ensure that concentrations of nutrients do not become a limiting factor for bioremediation. 

Typically, the manufacture of a batch of biopharmaceutical product entails filling the production vessel with the appropriate quantity of purified water. Heat-stable nutrients required for producer cell growth are then added and the resultant medium is sterilized in situ. This can be achieved by heat, and many fermenters have inbuilt heating elements or, alternatively, outer jackets through which steam can be passed in order to heat the vessel contents. Heat-labile ingredients can be sterilized by filtration and added to the fermenter after the heat step. Media composition can vary... 

Exact nutrient requirements of producer cell line to maximize cell growth and product production. 

The growth rate of cells is taken proportional to the cell concentration, x, and to an empirical form of the dependence on the concentration, p, of the nutrient. That empirical form was assumed by Monod (1942) to be the same as in the Michaelis-Mewnten model for enzyme kinetics. This makes the rate of cell growth,... 

Lechner, J. F. 1984. Interdependent regulation of epithelial cell rephcation by nutrients, hormones, growth factors, and cell density. Federation Proc 43 116-120. 

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-... 

Optimal conditions for insect cell growth have been extensively studied, but for product expression with a baculovirus infected insect cell the focus should be on the difference in the metabolic requirements of infected vs. uninfected cells, which has been observed to differ after infection. The alanine specific production rate decreases almost four-fold, while phenylalanine specific consumption rate increase 11-fold and glutamine specific consumption decrease [65]. Both an increase [66] and a decrease [67] in glucose consumption rates of insect cells after infection have been reported. This reflects some differences in the media and vectors that were used however, it is normal to expect a higher metabolic burden after infection due to the increase in protein expression rates caused by the infection. This creates a concern about the impact of nutrient limitations on the productivity of the system. 

---