Production of rubella hemagglutinating antigen in suspension cultures.

Rubella virus specific hemagglutinating antigen was prepared in the fluid phase of suspension cultures. Systems employing baby hamster kidney culture adapted inocula, nonadapted inocula, and cells derived from long-term infected suspension cultures were evaluated. Optimal specific hemagglutinating titers were obtained when kaolin-treated fetal bovine serum was used in the media and when the incoulum had previously been adapted in a suspension culture system. When cultures derived from long-term infected suspension systems were studied, the number of daily harvests in which acceptable titers were present was prolonged. However, titers were generally higher in suspension systems employing cells which had recently been infected.