Preparation, Characterization, and Efficacy of Cell Wall and Ribosomal Vaccines from Legionella Pneumophila

摘要

The Washington and Philadephia L-1 strains of Legionella pneumophila were mechanically disrupted and cell wall and ribosomal subunits isolated by differential centrifugation. Complete protection of AKR/J mice against challenge with the virulent Washington strain was obtained with intraperitoneal (i.p.) vaccination using as little as 5 micro of protein from ribosomes of the Washington strain. A higher concentration of ribosomal protein was required to achieve full protection when vaccination was by the subcutaneous (s.c.) route. Complete protection with cell wall preparations from the Washington strain was achieved by both i.p. and s.c. vaccination with 5 micro of cell wall protein. Vaccination i.p. with 50 micro of ribosomal antigen from the Philadelphia L-1 strain, resulted in 50% protection of mice against lethal challenge. Cell wall preparations, on the other hand, afforded full protection. Neither ribosomes or cell walls from Philadelphia L-1 protected mice when administered s.c. Microagglutination titers with Washington strain antigen, unlike those with Philadelphia L-1 antigen, correlated with protective response. Immunoprecipitin analyses indicated greater cross-reactivity between strains in those antisera produced with cell wall or ribosomal preparations from the Washington strain than in those produced with the Philadelphia L-1 strain preparations.