Use of polyethyleneglycol-treated serum for animal cell cultures.

Although many proteins will be removed from sera by precipitation with 10% polyethyleneglycol (PEG) the growth-promoting properties of such PEG-treated sera for many cell lines and cell strains are hardly reduced. Among the precipitated proteins are the macroglobulins which are difficult to remove from cell cultures and which may cause allergic reactions if incorporated into vaccines. The gammaglobulins are removed in this way as well. If the sera are contaminated with viruses or phages the titres will be reduced by approximately 4 logs and thus the incidence of virus contamination will be reduced by the PEG-treatment. For foot-and-mouth Disease (FMD) vaccine production PEG-treated sera from vaccinated cattle were applied for cell and virus cultivation. The virus obtained was subsequently precipitated with PEG and collected by filter-aid filtration. A concentrated virus product was obtained, which was practically devoid of serum proteins.