52 APPLIED IMMUNOLOGY 



jected immune to the toxin. Efforts to produce 

 immune sera by injections of gonococci themselves 

 have been more successful, and will be discussed under 

 antibacterial sera (Chapter VII). 



Antituberculosis Serum. — IMariagliano has pro- 

 duced a serum by immunizing horses with toxins made 

 from the filtrate of cultm-es of tubercle bacilli. His 

 favorable results have not been generally confirmed, 

 and antiserum is little used in tuberculosis. 



Antidysenteric Serum, — The dysentery bacilli of 

 the Shiga type form an extracellular toxin and from 

 this it is possible to prepare a true antitoxic serum. 

 The toxin, together with antidysenteric serum, is in- 

 jected into the horse in gradually increasing doses. 

 Killed cultures of the bacilli are also injected to give 

 the serum antibacterial properties. The standard 

 strength of the antiserum is such that 0.5 c.c. will pro- 

 tect a 1500-gramme rabbit against three times the 

 smallest fatal dose of toxin (Schorer). In Japan by 

 the use of this serum, the mortality of dysentery of the 

 Shiga type has been reduced from 28-37 per cent, to 

 8-12 per cent. In mild cases one dose of 10 c.c. of 

 serum is injected, in severer cases two injections of 

 10 c.c. are made six to ten hours apart, never more 

 than 20 c.c. in one day. Dysentery caused by bacilli 

 of the Shiga type is rare in the United States, being 

 largely confined to tropical and semitropical coun- 



