Serum Replacement - Hollow fiber cell culture bioreactor

CDM-HD is designed specifically for the culture of cells at high density and optimized for use in our hollow fiber bioreactor systems. Secreted products such as monoclonal antibodies and recombinant proteins are free of contaminating proteins from the medium and can be purified using simplified protocols, increasing net yield in many cases. CDM-HD provides lot-to-lot consistency and is an economical replacement for serum. It is available as a dry powder to make up one liter and is used at a concentration of 10%. The cost of CDM-HD is half that of serum giving you all the benefits of a chemically defined, protein free medium without the high price.

Hollow fiber cell culture is an ideal method for the production and collection of secreted products from mammalian cells. Large numbers of cells can be supported in a small space and the secreted product is concentrated to a high degree. The high surface area to volume ratio that hollow fiber bioreactors provide (100 cm²/mL or more) and the extreme high flux rates of fibers from FiberCell^® Systems can allow cells to grow at 100X the density found in flask culture (10⁸ vs. 10⁶/mL) and is in fact one of the only cell culture methods that permits cell cultures at densities that rival those found in vivo. High cell density allows cells to be grown in reduced serum environments (as low as 2% vs. 10% for conventional culture methods) and more easily adapted to commercially available serum free mediums. However, commercial serum free mediums can be expensive and can sometimes be optimal for only a limited number of cell types. The concept of CDM-HD is simple: produce a universal serum substitute that can take advantage of the simplified serum requirements for cells grown at high densities in hollow fiber bioreactor systems. CDM-HD represents a true breakthrough in cell culture ideology and technology. It is the first time that a specific culture system is used to take advantage of the growth properties of the cells in that system to simplify and optimize a medium for those specific growth conditions.

The cultivation of cells in vitro has become an important tool for biomedical research and recombinant production purposes. The supplementation of mammalian cell culture media with sera of animal origin remains still standard, providing necessary nutrition, attachment factors, shear protection, growth factors and cytokines. Because of undefined composition, risk of contaminations, cost factors and also animal welfare considerations, the switch to serum free alternatives is promoted by regulatory authorities, industry and academics in general.

The beneficial effects of serum supplementation is limited by several disadvantages: serum is an ill-defined mixture and often contains adventitious agents and by-products like bacterial endotoxins and other immunogenic contaminants. Furthermore batch qualities vary and the costs can be high. Sera are a major source of viral contaminants which often do not produce cytopathic effects or morphological changes but once present are almost impossible to remove from cultures. Some important advantages in the use of totally defined media are the avoidance of risks of contamination and immunogenic stimuli and lot to lot consistency Possible contaminants include viruses, prions and mycoplasma which highly impair pharmacologic use of culture derived products. Taking things one step further a totally defined, animal component free, protein free medium will not contain any proteins nor any materials derived from animals. Purification of the desired secreted product is facilitated and regulatory compliance is made much simpler.

Instructions for use: Reconstitute the contents of one bottle of CDM-HD to make a total volume of 1 liter. Sterile filter, do not autoclave. Add to any basal medium at a concentration of 10%. When using with FiberCell^® Systems hollow fiber bioreactors add 10% fetal calf serum to the cell innoculum when loading cells. No adaptation is required though you may see a reduction in glucose uptake rate for the first day or two of use. CDM-HD is stable for at least 2 months as a concentrate when stored at 4 degrees and away from light.

CDM-HD will not require any adaptation but is optimized for cells growing at high density. For best results switch to CDM-HD after cells have reached a high density inside the FiberCell^® Systems hollow fiber bioreactor, typically after one week of culture or so.
CDM-HD does not contain any carbon source. When working with a low glucose medium such as RPMI it is important to supplement the glucose concentration to 4.5 grams per liter.
CDM-HD is protein free and does not contain any cell attachment factors. When innoculating cells in medium containing CDM-HD add 10% FBS to the cell innoculum only. This will provide the required attachment factors for adherent cells. This is not required for suspension cells though hybridoma cell lines should be treated as adherent cells.
CDM-HD can be used in other culture systems such as spinner culture and roller culture. For these applications add plurionic F60 or some other cell membrane protecting surfactant.
CDM-HD is protein free. The secreted protein of interest may be the only significant protein present in your cell culture supernatant. You should re-evaluate your purification protocols as entire steps can sometimes be eliminated, increasing yield. Keep in mind that CDM-HD is protein free and contains no ferritin so the free iron levels will be higher than in standard mediums. Pay attention to any chelating agents that may be part of your buffers or purification protocol.

Please contact us for more information on our CDM-HD Serum Replacement.