Comparative Immunologic Studies of Cell Structures Isolated from Salmonella Typhosa

Abstract

The cell walls of Salmonella typhosa strains Ty2 and 0-901 exhibited similar lethality for mice as did the intact cells, whereas the isolated protoplasts and protoplasmic membranes were less toxic. Antigenic analysis showed that the somatic complex was a constituent of the protoplast membrane. No distinctive antigens could be detected as constituents of protoplasts or membranes. The protective potency of protoplasts of strain Ty2 was dependent upon retention of the Vi antigen. The addition of Vi antigen to protoplasts prepared from the Vi negative strain 0-901 resulted in their agglutination in specific Vi antiserum.