Serum is a complex supplement containing proteins, growth factors, hormones, amino acids, sugars, trypsin inhibitors, and lipids. Although the major constituents of serum are known such as albumin and transferrin, some of the minor com -ponents and their effect on cell growth have not been fully determined. These minor components include nutrients such as amino acids, nucleosides, and sugars, growth factors, hormones, minerals, and lipids.
Downstream purification is the leading disadvantage to using serum in cell culture media. For example, monoclonal antibody production and recombinant protein secretion both require purification to remove serum-derived gamma globulin from the media. Insulin-Transferrin-Selenium Solution II(100X), is a growth supplement that should be added at 10 mL/L medium. Supple-mentation enables a reduction in the FBS requirements of the culture. The components of ITS are required for optimal perfor-mance of cells in serum-free culture. All components are derived from non-animal source.