272 PROTEIN POISONS 



THE EFFECTS OF INTRAPERITONEAL INJECTIONS OF THE AIR-DRIED CELLS 

 OF SARCINA AURANTIACA IN GUINEA-PIGS 



No. Weight in gm. Dose in mg. Result. 



1 240 25 + 



2 300 15 -;- 



3 305 10 



THE EFFECTS OF INTRAPERITONEAL INJECTIONS OF THE FINELY-GROUND 

 CELLS OF THE COLON BACILLUS IN GUINEA-PIGS 



No. Weight in gm. Dose in mg. Result. 



1 172 4.09 + 



2 170 4.05 + 



3 165 3.66 + 



4 195 2.60 + 



5 135 1.80 + 



6 145 1.45 + 



7 165 0.825 + 



8 200 0.10 



9 175 0.085 



10 162 0.081 



As is well known, rabbits repeatedly treated with some 

 foreign protein, such as horse serum, furnish a serum 

 which precipitates the foreign protein in vitro. The rabbit 

 at the same time, and by the same treatment, is sensitized. 

 Quite naturally one suspects that toxogens and precipitins 

 are identical. Friedemann was the first to test this question 

 experimentally. He mixed the blood serum of sensitized 

 rabbits in vitro, in varying proportions with the homologous 

 anaphylactogen. The precipitate which formed was col- 

 lected and washed in the centrifuge; then it was digested 

 with fresh rabbit serum in order to supply the complement. 

 Such preparations after varying periods of digestion, were 

 injected intravenously into rabbits, but with negative results. 

 Friedberger, 1 using guinea-pigs instead of rabbits, succeeded 

 fully in producing the anaphylactic poison by this method. 

 For two reasons the guinea-pig is better suited for this 

 work than the rabbit. The blood of the former is richer 

 in complement, and this animal is the more susceptible 

 to the action of the anaphylactic poison. However, in 



1 Zeitsch. f. Immunitatsforschung, iv, 636. 



