Noguchi's Modification 305 



(3) The Antigen. — The antigen is made, according to the direc- 

 tions given in the description of the Wassermann test, out of normal 

 guinea-pig heart. The extract is dried upon filter-paper, as has 

 been recommended for the hemolytic amboceptor, and titrated ac- 

 cording to the size of the square of paper needed, instead of the quan- 

 tity of fluid to be added. 



(4) The Corpuscle Suspension. — For this purpose either normal 

 human corpuscles or the corpuscles of the patient whose blood is to 

 be examined may be employed. Instead of a 5 per cent, suspension 

 a I per cent, suspension is recommended. If normal corpuscles are 

 employed, it is necessary to wash them free of the normal serum or 

 plasma, which Noguchi accompUshes as follows: 8 cc. of normal salt 

 solution are placed in a large test-tube, and the blood flowing from- 

 a puncture (in the operator's own finger, for example) permitted to 

 drop in, the proportion being i drop each 4 cc. The fluid is then 

 shaken and stood on ice over night, when the corpuscle sediment 

 and the supernatant fluid containing the fibrin factors and ferment 

 is decanted and replaced by fresh salt solution, and the suspension 

 made by shaking. Or, in a laboratory, the corpuscles can be washed 

 as usual with the aid of the centrifuge. If the patient's own cor- 

 puscles are to be employed, some of them may be distributed, 

 through the serum without any washing, by simply shaking it up 

 a litde with the clot. It is not essential exactly to measure the 

 corpuscles, as after a few trials with the suspension of normal cor- 

 puscles the eye becomes accustomed to the color, intensity, and 

 density corresponding to the requirement. 



(s) The Antihuman Hemolytic Amboceptor. — This is prepared 

 by injecting rabbits, according to the method already described, 

 with washed human corpuscles obtained from fresh human placentae 

 or from the heart of a fresh cadaver come to autopsy. The 

 serum of the rabbit, when obtained, is dried upon blotting-paper and 

 titrated as already described. 



The "set-up" for the test, as given by Noguchi, is less cumber- 

 some than that recommended for the Wassermann test and includes 

 six tubes. It can best be understood by reference to the diagram. 



The method recommends itself through its simplicity and con- 

 venience, no sheep corpuscles being used, and through the smaller 

 quantity of blood required, it seeming to the patient that less 

 damage is done by pricking the finger than by introducing a syringe 

 needle into a vein. It is, moreover, a very sensitive test, and gives 

 very accurate results as far as regards positive cases. Unfortunately, 

 it seems to have the demerit of occasionally finding the reaction in 

 negative cases. 



Diagnosticians are still divided in opinion, some preferring the 

 Wassermann test, some the Noguchi test, and some always doing 

 both, permitting the one to control the other. 



