[The virulence of Yersinia pestis strains in serial-passage in guinea pig peritoneal macrophages].

The cultivation of Y.pestis virulent strains in macrophages of guinea pigs has been found to enhance their virulence, decreased during storage, and to increase their antiphagocytic and cytopathic properties. This effect makes it expedient to recommend the passage of Y.pestis through peritoneal macrophages of guinea pigs with the aim of stabilizing their virulence. The proposed method reduces the duration of investigation 6 times, decreases the number of experimental animals used in the investigation and permits the simultaneous passage of a large number of subcultures.