Albumins are an important component of many serum-free cell culture systems such as those that utilize hybridoma or Chinese Hamster Ovary (CHO) cells. Not all albumins have the same efficacy in culture media. Major factors that control the activity of albumin include the quality and relative quantity of specific ligands associated with the molecule.
The ligands associated with albumin are determined largely by the nutritional status of the source animal and the purification process. This explains why the effectiveness of albumin(s) in a given cell culture system may vary and must be controlled. The ligand profile also helps to explain why natural albumin(s) derived from human (HSA) or bovine (FBS) sera perform
differently than recombinant albumin(s) in cell culture.