270 INFECTION AND IMMUNITY 



Noguchi's Modification. — Noguchi^has much simplified the test by 

 making use of an anti-human hemolytic amboceptor instead of an anti- 

 sheep amboceptor. In this way, he avoids the necessity of procuring 

 fresh sheep corpuscles for each test by using the corpuscles of the patient 

 himself. He has determined empirically that human serum contains, 

 normally, no amboceptor active against the human red corpuscles. 

 This fact is extremely important and has a decided advantage over 

 the original Wassermann test, in that in any reaction in which sheep 

 corpuscles are used as an indicator with human serum, the actual amount 

 of hemolytic amboceptor used in the test is uncertain. For, as we have 

 mentioned above, human serum, normally, may contain a variable 

 quantity of amboceptor for sheep corpuscles. In Noguchi's test, there- 

 fore, the actual quantity of amboceptor is exactly known by previous 

 titration. The hemolytic amboceptor for Noguchi's test is obtained by 

 four or five injections of washed human corpuscles into rabbits. These 

 corpuscles may be obtained from the heart's blood at autopsies, or 

 better, if possible, from placentae at childbirth. The unit for this 

 amboceptor is obtained by titration as in the case of the sheep-blood 

 amboceptor for the original Wassermann test. In setting up Noguchi's 

 test, the following substances are used: — ■ 



(o) Patient's serum. Obtained in small glass capside. About 2 

 c.c. should be taken. 



(6) Complement. Fresh guinea-pig serum: 0.1 c.c. of a forty per 

 cent, fresh, guinea-pig serum in salt solution is used in the test. Obtain 

 by adding 1 part of guinea-pig serum to one and one-half parts of salt 

 solution. 



(c) Antigen. Substance prepared as in the Wassermann test by 

 extraction of syphilitic or normal organ. 



(d) Human corpuscles. Normal corpuscles or those of the patient 

 himself may be employed. If the patient's red cells are chosen, these 

 should not be used for other tests than that on the patient's own serum; 

 1 c.c. of a one per cent emulsion of washed corpuscles is used for the 

 test. 



(e) Anti-human amboceptor prepared by the injection of washed 

 human corpuscles into rabbits and titrated against human corpuscles. 

 Two units are used in the test. 



The test itself is set up as follows : 



' Noguchi. Jour, of Exper. Medicine, 1909. 



