190 



Scientific Proceedings (108). 



Animal charcoal and globulin (horse serum) were used to 

 adsorb the substances possessing antigenic action from the filtrates. 

 When animal charcoal was added, the antigenic properties were 

 removed, and could not be recovered by extraction of the charcoal. 

 The adsorption with globulin was a more complicated procedure. 

 The technique was briefly as follows: The original antigen was 

 dialyzed and horse serum, one part to twenty of antigen, was 

 added and allowed to stand in the incubator half an hour. The 

 globulin was then precipitated by passing purified C0 2 gas free 

 from HC1 through the mixture for one half an hour at 37 0 C. 

 The globulin precipitate was collected and by shaking it with 

 alcohol the antigenic substances were extracted. The alcoholic 

 extract was concentrated in a vacuum. 



The preliminary dialysis of the culture filtrate eliminated 

 practically all of its anticomplementary action. The adsorption 

 with globulin removed the antigenic substances from the culture 

 filtrates and the aqueous extractions so that they were easily 

 obtained in greatly purified and concentrated form. 



In preliminary studies the antigens which are used in the 

 diagnosis of syphilis by complement-fixation were also purified 

 and concentrated by similar methods. This method thus allows 

 more precise study of many phases of infection and immunity 

 than has hitherto been possible. 



101 (1561) 



Observations on the immunization of rabbits with single strain 

 and combined multiple strain vaccines. 



By W. C. Noble, Jr. and Ruth A. Thomas. 



[From the Department of Bacteriology, New York University {Uni- 

 versity and Bellevue Hospital Medical College).] 



Previous to 1 91 6, the Army and the National Guard were 

 immunized with typhoid vaccine. During the late summer and 

 early autumn of that year, numerous cases of paratyphoid fever 

 developed among the troops along the Mexican border, and the 

 Army medical authorities therefore felt it desirable to substitute 

 a triple vaccine, of typhoid bacilli combined with the paraty- 



