Antileptospiral agglutinins produced in rabbits.

Agglutinating antibodies produced in an adult rabbit in response to intravenous injections of live Leptospira sp. (serotype biflexa, strain Waz), consisted of a 19S component (present at day 6 after inoculation) and a 7S component (present at day 6 after inoculation). Both 19S and 7S antibodies persisted in the serum until the conclusion of the observations (day 216). The 19S antibody was completely destroyed by 2-mercaptoethanol but the 7S antibody was only partially sensitive to 2-mercaptoethanol.The serum proteins present in the 19S and 7S serum fractions were determined by immunoelectrophoresis and cellulose acetate electrophoresis. Elution of the serum components from cellulose acetate membranes directly confirmed that the beta-migrating IgM was the 19S serum component with leptospiral agglutinating activity and that gamma-migrating IgG was the 7S serum component with antileptospiral agglutinating activity.