THE MANUFACTURE OF ANTISERA 745 



theria antitoxin, being usually distributed in glass syringe containers. 

 The product is used in both human and veterinary practice. 



PERFRINGENS ANTITOXIN. During the last two years of the 

 recent world war, considerable attention was devoted to the experi- 

 mental development of perfringens antitoxin or anti- gas gangrene 

 serum. The use of this serum in conjunction with tetanus antitoxin 

 was adopted by the War Department during the later months of the 

 war. It is prepared by the injection of horses with Bad. Welchii toxin. 

 The strength of the toxin is determined by the injection of pigeons 

 which are uniformly susceptible to the substance. The antitoxin is 

 standardized by injection of pigeons with mixtures of serum under test 

 and varying amounts of standardized toxin. The sudden termination 

 of the war did not permit the accumulation of conclusive evidence 

 regarding the efficacy of perfringens antitoxin. 



ANTIMICROBIAL SERA 



In addition to diphtheria and tetanus antitoxins, certain other 

 antisera are rapidly attaining practical significance. At present, 

 however, no methods are in use by which- any antisera other than 

 diphtheria and tetanus antitoxins can be accurately standardized as 

 to potency. Nevertheless, most of the products can be submitted to 

 rigid tests in order to determine the presence of protective qualities. 



ANTIMENINGOCOCCIC SERUM. Horses are immunized to cultures of 

 a number of strains of M . intracellularis var. meningitidis, the activity 

 of the resulting serum being determined by agglutination and com- 

 plement fixation tests. Antimeningococcic serum is used in the active 

 treatment of cerebrospinal meningitis and is administered by lumbar 

 puncture. The dose depends principally upon the age of the patient 

 and the condition of the blood pressure. 



ANTISTREPTOCOCCIC SERUM. Bouillon cultures of Strept. pyogenes 

 are killed by heating, and injected into horses in increasingly larger 

 doses. Frequently, the killed cultures used in treating the horses are 

 composed of several different strains of the streptococcus. In this case 

 the resulting antistreptococcic serum is designated as " polyvalent," 

 while the serum obtained after the injection of cultures consisting of 

 but one strain of the organism, is called "monovalent" antistreptococcic 

 serum. 



