PRACTICAL APPLICATIONS OF METHOD 



209 



Reagents 



1. Sensitizer prepared by injecting washed human blood corpuscles into 

 rabbits. 



2. 1 per cent, emulsion of washed human blood cells. 



3. Alexin fresh guinea pig serum diluted with one and one-half volumes 

 of salt solution, 40 per cent. 



The reaction is performed in the following way : 

 Noguchi's Method of Complement Fixation for the Serum Diagnosis of Syphilis 



* When working with inactivated serum 4 drops (0.08 c. c.) should be em- 

 ployed. With cerebrospinal fluid, 0.2 c. c. (not inactivated) is used. 



(Taken from Noguchi's "Serum Diagnosis of Syphilis," Lippincott, 1910, 

 p. 57.) 



Bauer 30 has introduced a modification in which he utilizes the 

 presence of normal sheep sensitizer in many human sera. He per- 

 forms his tests without the addition of antisheep sensitizer at 

 first, adding this only to those tubes in which controls have shown 

 that no normal sensitizer is present. Stern, 31 on the other hand, 

 utilizes the alexin normally present in human serum. The syphi- 

 litic serum to be tested is, therefore, not inactivated, and the 

 sheep cells are more heavily sensitized (9 to 12 units). It seems 

 to us that this method is objectionable chiefly because of the 

 anticomplementary action which develops in most normal human 

 sera if kept for a short time, and which can be removed only by 

 inactivation. 



Other modifications of the Wassermann reaction are those of 



30 Bauer. Semaine Medicale, 28, 1908. 



31 Stern. Zeitschr. f. Imm., Vol. 1, 1909. 



