[Immunoglobulin FAB-fragments: specific activity and reactogenicity. III. Comparative study of the antigenic properties of anti-encephalitic gamma-globulin and FAB-fragments isolated from it].

Parenteral administration of antiencephalytic gamma-globulin and of the Fab-fragments, extracted from it, to rabbits stimulated the formation of specific antibodies. The maximal blood serum specific antibody level in rabbits reimmunized with Fab-fragments was much lower than that following the reimmunization of rabbits with gamma-globulin. Antibodies specific to gamma-globulin and Fab-fragments were concentrated in the gamma-globulin fraction of the immune sera and could be referred to the immunoglobulins of G class.