Concentration and Purification of Antityphoid Horse Serum.

Abstract

Extremely severe hemorrhagic necrosis appears in rabbits at the skin sites prepared by an injection of a bacterial filtrate when the injection is followed 24 hours later by an intravenous injection (i. e., reacting factors) of a culture filtrate of the same or another bacterium. 1 , 2 , 3 , 4 Among the various phases of this phenomenon of local skin reactivity, the specific neutralization of the reacting factors by homologous immune sera was observed. A method has been described for quantitative measurement of the neutralizing antibodies of immune antimeningococcus and antityphoid horse sera. Inasmuch as the titer of these antibodies did not run parallel to the agglutination titer of the same sera, advantage was taken of this method 2 , 3 in order to develop highly potent neutralizing horse sera for ultimate therapeutic application. The work reported below was undertaken in order to concentrate and purify the antityphoid neutralizing antibodies.

Concentrated and purified antibody solutions should contain a maximum amount of antibodies associated with a minimum of total solids, especially of protein, as indicated by the nitrogen content. Gibson and Banzhaf 5 , 6 were able to obtain three to fourfold concentration of diphtheria and of tetanus antitoxins from antisera. Preparations of pneumococcus antibody solutions by methods of Banzhaf, 7 and Banzhaf and Sobotka, 8 and by other methods, yield concentrations up to 7-10 times the amount of protective units found in the original serum. It should be noted that only solutions containing the identical amount of total solids or nitrogen may be directly compared. By the following method we are able to reach a much greater concentration as demonstrated by the phenomenon of local skin reactivity to B. typhosus.