The cell culture flask CELLine is a disposable bioreactor based on two-compartment technology. It allows to cultivate cells at highest densities (10^7-10^8 cells/ml) and to express proteins like monoclonal antibodies at very high concentrations. The bioreactor CELLine is separated into a medium and a cell compartment by means of a 10 kDa semi-permeable membrane. This membrane allows a continuous diffusion of nutrients into the cell compartment with a concurrent removal of any inhibitory waste. The individual accessibility of the compartments allows supplying cells with fresh medium without mechanically interfering with the culture. Optimal oxygen supply and control of carbon dioxide levels is ensured by a silicone membrane which forms the cell compartment base. The bioreactor CELLine is suitable for both animal and plant cells either growing in suspension or as adherent cells. Two types are available, ideal for suspension cells or anchorage-dependent cells. Features and benefits: - Expression of proteins at concentrations 50 times higher than with standard culture flask. - Handling as easy as using normal tissue culture flasks. - Less consumption of supplements like serum, therefore reducing costs.