Efficient Expression of a Transfected Foreign Gene by Cos1 Cells in Serum-free Medium

In this report, we have found that fatty acid-free bovine serum albumin stimulated the expression of a transfected foreign gene in Cos1 cells in serum-free medium and that its activity was as same as that of fetal calf serum. This will simplify the purification of the gene product from the culture medium.