HOST RESPONSE TO ANTIGENIC ACTION 451 



been removed, also rendered guinea pigs anaphylactically hyper- 

 sensitive to the A substance in the homologous autolysate. Before 

 the removal of the anticarbohydrate antibody by precipitation in 

 vitro, the serum sensitized guinea pigs to the type-specific soluble 

 substance. After the antibody had been eliminated, animals in- 

 jected with the serum failed to react to the injection of the car- 

 bohydrate, but responded typically when injected with the autoly- 

 sate from virulent organisms of Type I. Furthermore, the animals 

 showed no symptoms following the intravenous administration of 

 autolysate derived from a rough strain of Type I or of autoly- 

 sates of smooth strains of Types II and III. 



The experiments in anaphylaxis showed that in the serum of 

 rabbits receiving injections of formalinized pneumococci an anti- 

 body develops that reacts specifically with an antigen found in the 

 autolytic products of Type I Pneumococcus. Similar autolysates 

 of the other two types (II and III) of this organism, as well as 

 rough strains derived from homologous or heterologous types, 

 elicited no anaphylactic symptoms in guinea pigs. Under the same 

 conditions, the nucleoprotein was likewise incapable of provoking 

 specific shock. That the antigen in Type I autolysate responsible 

 for the anaphylactic symptoms was not the specific carbohydrate 

 appeared to Enders to be shown not only by the failure of the lat- 

 ter material, when pure, to produce shock in guinea pigs sensitized 

 with anti-A rabbit serum, but also by the experiments with rabbit 

 serum from which the carbohydrate antibody originally capable 

 of sensitizing the animals had been removed, leaving unimpaired 

 the power of the serum to sensitize the animals to the A substance. 



The cellular carbohydrate from Type I Pneumococcus, like- 

 wise, caused immediate, lethal anaphylactic intoxication in guinea 

 pigs previously injected with Type I antipneumococcic rabbit 

 serum. Schiemann, Loewenthal, and Hackenthal 1231 reported a 

 similar effect obtained with the carbohydrate preparation made 

 by the method of Schiemann and Casper. 1228 These results, taken 

 with further observations of Avery and Goebel (1931) 45 on the 



