Certain aspects of foot--and--mouth disease. Virus production in growing BHK suspended cell cultures

Abstract

Production of FMDV in growing BHK suspended cell cultures offers several technical advantages: no medium change and no sedimentation of cells prior to infection are needed, thus saving time and medium. However, the final product should be as free of serum proteins as possible. For this purpose polyethylene-glycol-(PEG)-treated serum can be used for the stimulation of cell growth in combination with precipitation of the virus with PEG. With this method virus preparations are obtained in which practically no serum proteins can be estimated. Recently the use of serum-free medium has been reported for a BHK line which had been adapted to this medium. This also offers possibilities of virus cultivation in growing cells. Two of our BHK lines also grow in a cheap serum-free medium in which amino acids are replaced by a combination of lactalbumin hydrolysate and peptic peptone. With BHK cells adapted to this medium high cell yields are obtained. The use of PEG-treated serum will be compared with the use of the low cost serum-free medium with respect to FMDV production.