Hypersensitiveness to Diphtheria Bacterial Products: Inhibition of the Anaphylaxis of Antitoxic Immune (Actively Sensitized) Guinea Pigs

Summary This paper reports further experiments on guinea pigs actively sensitized against diphtheria toxoid filtrate. Five points are made. First, that the anaphylactic reaction of the actively sensitized guinea pigs is inhibited by incubation of the test dose of antigen (toxin or toxoid filtrate) in mixture with antitoxic horse globulin prior to its intravenous injection. Second, that actively sensitized guinea pigs are made refractory by intravenous injection of the antitoxic horse globulin or serum shortly before the test injection of the toxin or toxoid filtrate antigen. Third, that guinea pigs anaphylactically reactive to toxoid filtrate are made refractory by subcutaneous injections of toxoid filtrate ten and seven days before the time of intravenous test, but not by similar injections of diphtheria bacterial vaccine. Fourth, that the anaphylactic reaction is inhibited if filtrate absorbed with antitoxic rabbit serum is used as the intravenous antigen, but not if filtrate similarly absorbed with antibacterial rabbit serum is used. Fifth, that the capacity of toxoid filtrate either to invoke antitoxic immunity or to actively sensitize, is greatly reduced, and under certain quantitative conditions entirely lost, if filtrate absorbed with antitoxic rabbit serum is used as immunizing or sensitizing material, while the same filtrate similarly treated with antibacterial rabbit serum retains the capacity both to invoke antitoxin production and to sensitize against the toxoid filtrate.