INFECTIONS OF THE DIGESTIVE TRACT 175 



ably prepared animal. It has further been found that 

 as the result of long preparation with such exudates 

 guinea-pigs, rabbits, and sheep furnish a serum which in 

 amounts of one-half cubic centimeter is able to protect 

 animals from intraperitoneal infection. It is claimed 

 by Kikuchi l that the immune serum obtained through 

 treatment with "aggressins" does not show in vitro the 

 well-known characteristics of a bacteriolytic serum and it 

 is maintained that this " anti-aggressin " action is the 

 basis of a new type of immunity. The validity of the 

 latter claim cannot be successfully upheld without further 

 research in this complex problem. There are now two 

 well-known antidysenteric sera designed for human use : 

 one prepared by Shiga by immunization with the bacilli 

 of the originally discovered strain of dysentery; the 

 other made at the instigation of Dr. Flexner by means of 

 the variety of bacillus bearing his name. These sera 

 are regarded as being essentially bactericidal, but there 

 is room for doubts as to how far the bactericidal action 

 exhibited in vitro is operative after the serum has been 

 put into the dysenteric patient. That these sera, 

 though not universally applicable, are quickly effective 

 in some instances of severe dysentery is certain. The 

 effect consists mainly in a diminution in the number of 

 movements, alleviation of tenesmus, some lowering of 

 the temperature, and a calming of the nervous system 

 which is sometimes very striking. These effects may 



1 "Weitere Erfahrungen fiber Aggressinimmunitat gegen den 

 Shiga-Kruseschen Dysenteriebazillen," Archiv f. Hyg., liv, p. 298, 

 1905. 



