Abstract
Ribosomal proteins isolated from Salmonella typhimurium were effective in inducing immunity in mice. This immunity was specific since animals immunized with ribosomal proteins from S. typhimurium were not protected against challenge with S. cholerae-suis or S. enteritidis. Immunity was evident as early as 5 days after immunization. Ribosomal ribonucleic acid (RNA) failed to provide any effective immunity in mice. Polyinosinic acid: polycytidylic acid (poly I: C) induced a rapid, short-lived immunity to all three Salmonella species. In contrast, ribosomal RNA failed to elicit any rapid nonspecific response to infection.