Immunizing effects of structural components of Leptospira icterohaemorrhagiae.

The protective attributes of the structural components of Leptospira icterohaemorrhagiae strain Shibaura were examined. Guinea pigs were immunized with the outer envelope, the cell wall, the type-specific main antigen, and the protein constituent of the outer envelope respectively. Of the 4 preparations, the outer envelope, the cell wall and the type-specific main antigen showed a considerable protective effect in this order. The protein constituent of the outer envelope was less effective. Immunization with 200 mug of the outer envelope protected guinea pigs from lethal infection but no completely from the renal carrier state. The rate of protection from renal leptospirosis by the preparations of leptospiral components and lyophilized whole cells was always inferior to the survivor rate.