Induction of immunological tolerance to human gamma-globulin in rabbits using the maternal route of inoculation

A method of producing tolerance in rabbits to human γ-globulin is described. This method differs from those in common use in that the antigen is administered to the mother, rather than direct to the foetus, and allowed to pass across the foetal—maternal barrier. Attention is drawn to the importance of the timing of administration of antigen in relation to the duration of pregnancy in order to avoid interference by maternal antibody.