Properties of foot-and-mouth disease virus in tissue culture I. Changes in plaque morphology and antigenicity following passage in tissue culture

Summary

By passage of the Brussels-O strain of foot-and-mouth disease virus through tissue cultures, variants were obtained which differed from the original virus in antigenicity, antigenic character, and rate of neutralization by homologous and probably also heterologous antibodies. Further, a variant forming a plaque-pattern different from that of the parental strain was obtained. An increase in cytopathogenicity was also observed during tissue-culture passages. The nature of the variance is discussed, and it seems probable that passage through tissue culture selectively favours the virus of the variant type in the heterogenous original population.