Culture unit

Klerx, J. P. A M., Jansen Verplanke, C., Blonk, C. G, and Twaalfhoven, L. C (1988) In vitro production of monoclonal antibodies under serum-free conditions using a compact and inexpensive hollow fibre cell culture unit. J Immunol Methods 111, 179-188. 

The protocols for using the Verax System One are supphed with the culture unit and have been published previously (Looby, 1993). The culture productivity data presented in Tables 5.9.1 and 5.9.2 demonstrate its capabihty in comparison with other systems and during scale-up. 

Fig. 1. Time course of penicillinase induction in Bacillus cereus 569 after induction by 1 unit of benzylpenicillin/ml. Data from Pollock [12]. Cultures diluted 1 2 in fresh medium at 2 hours and every i hour thereafter. X = growth of induced culture = growth of control culture = total penicillinase in induced culture (units/ml original culture) = total penicillinase in control culture (units/ml original culture) O = specific activity of induced culture (penicillinase units/mg cells) A = specific activity of control culture.

Pollock [12] discovered that the induced penicillinase synthesis lasted at least 5 hours, though by this time the specific activity of the culture (units of penicilUnase per milligram dry weight of bacteria) had passed its peak (at ca. 2.5 hours) and was almost back to the original basal level. The course of penicillinase synthesis was similar if, a short time after exposure to penicillin (even at 0°C), the cells were washed and regrown in fresh medium. This drew attention to the possibility of the inducer s remaining associated with the cells, and this was tested by penicillin binding studies. 

There have been a number of membrane-based culture units developed (24), many based on dialysis tubing (1), and even available as large fermenters (Bioengineering AG Membrane Laboratory Fermenter with a Cuphron dialysis membrane of 10 000 dalton molecular weight cut-off forming an inner chamber). One of the more successful and currently available systems is described here—the miniPerm Bioreactor (Heraeus Instruments). 

Working volume litre CuHuie volume /sbe Culture unit Total cells Antibody yield mg Normalized yield mg/litte ... 

Columbia (Spacecraft)-Accidents. 2. Corporate culture-United States-Case studies. 

Koopman MM, van t Ende E, LieshoutKrikke R, Marcelis J, Smid WM, de Korte D. Bacterial screening of platelet concentrates results of 2 years active surveillance of transfused positive cultured units released as negative to date. Vox Sang 2009 97(4) 355-7. 

Althou hybridoma cells are spherical and well adapted to suspension culture they do grow well in stationary culture resting on the substrate, sometimes with very light attachment. This means that a wide selection of culture vessels and systems are available for their culture ranging from a simple tissue culture plate or flask to highly sophisticated bioreactors with full instrumentation to control the physiological environment (1-3). Commercially hybridoma cell lines are grown at scales up to 2000 litres and beyond in culture units scaled-up from laboratory size vessels. Laboratory, pilot, and production scale is ill-defined so in this chapter laboratoiy scale will be taken as 10 litre volume cultures, and below. 

Site number 4 in Lgki Wielkie was discovered in 1933 and verified in 1987. The most recent excavations were conducted in 2009. The following cultural units have been registered ... 

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