title: Antigenic variants of leptospiras selected by antiserum-complement mediated-killing.
abstract: The presence of antigenic variants of leptospiras was confirmed by the leptospiricidal reaction mediated by the antiserum plus complement. More than 99% of the organisms of virulent L. copenhageni Shibaura were destroyed microscopically after treatment with the anti-L. copenhageni Shibaura antiserum (1: 2000) plus guinea pig complement (1: 20). The leptospiras which survived treatment with the antiserum plus complement produced colonies on the solid serum medium at a rate of 0.09%. Eighty-seven percent of the survivors were found to be antigenic variants. The antigenicity of these variants reversed to that of the parent after 3--5 passages in the liquid normal serum medium.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics* / Q000276:immunology; D003165:Complement System Proteins / Q000276:immunology; D006224:Cricetinae; D014644:Genetic Variation; D006168:Guinea Pigs / Q000276:immunology; D007106:Immune Sera; D007158:Immunologic Techniques; D007919:Leptospira / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D008297:Male; D011817:Rabbits / Q000276:immunology; D013045:Species Specificity; D014774:Virulence
chemical_list: D000942:Antigens, Bacterial; D007106:Immune Sera; D003165:Complement System Proteins