Passive Anaphylaxis in the Guinea Pig and Its Inhibition by an Extraneous Antigen-Antibody Reaction

Summary Relationships of antigen and antibody concentration have been studied in passive anaphylaxis of the guinea pig challenged by aerosol. Inhibition of anaphylaxis in sensitized animals by an unrelated antigen and antibody has been found to be dependent on concentration. Injection of washed aggregates of the unrelated system was ineffective although the same small reduction of serum complement was produced as with the effective method of separately injecting antigen and antibody. Administration of serum previously treated in vitro with extraneous antigen and antibody also produced refractoriness to challenge. The kinetic relationships of antigen and antibody and the possible role of serum factors in anaphylaxis and in the inhibition of anaphylaxis have been discussed.