NOGUCHI TEST 175 



adhesive plaster labels with the name of the patient written on it as well as the number. 

 The greatest care should be exercised to avoid mistakes in numbers. 



Many workers prefer to use inactivated serum for the test. In this case we should 

 add four times as much of the inactivated serum as for the unheated serum (0.08 

 instead of 0.02). 



Inactivation not only destroys complement but likewise diminishes 

 the strength of the reagine content of the serum. Factors such as 

 character of food and general condition influence the complement 

 strength of guinea-pig serum so that it is advisable to titrate the guinea- 

 pig serum. To do this take i c.c. of a J^% emulsion of human red 

 cells and drop in i unit of amboceptor paper. The amount of com- 

 plement which will entirely haemolize the red cells in one-half an hour in 

 water-bath equals i unit of complement. For the test use 2 units of 

 complement. 



Some workers prefer to use a single unit of complement and 2 units of ambo- 

 ceptor, thus doubling the amboceptor unit. Stimson has found, however, that 

 increasing amboceptor content may cause a deviation of Complement, so that he prefers 

 to use a single unit of amboceptor and 2 units of complement. In the original 

 Wassermann technic the units of both complement and amboceptor are doubled. 

 In the Noguchi only the amboceptor unit is doubled. 



Preparation of Acetone Insoluble Antigen. Take about 50 grams of finely divided 

 beef, dog, or rabbit heart or liver and triturate in a mortar to a paste. Pour on this 

 paste 500 c.c. of absolute alcohol and keep the mixture in a corked bottle in the 37C. 

 incubator for five to seven days shaking the emulsion four or five times daily. (We 

 use beef heart and carefully pare away all fat and fibrous tissue and macerate the re- 

 maining muscular tissue with absolute or 96% alcohol. Next filter through paper 

 and collect the filtrate in a large shallow dish and hasten evaporation with the aid 

 of a current of air from an electric fan directed upon the surface. It is advisable to 

 cover the dish with a single layer of cheese cloth to prevent access of flies, etc., to the 

 contents. These insects may contaminate the solution with moulds which causes 

 disappearance of the lipoids. 



Within twenty-four hours only a sticky residue should remain. This is taken up 

 in about 50 c.c. of ether and the turbid ethereal solution kept over night in the re- 

 frigerator in a corked bottle. 



In the morning there will be found about 45 c.c. of clear supernatant fluid which is 

 decanted off and allowed to evaporate to about 15 c.c. 



Now to this 15 c.c. add about 150 c.c. of acetone and a precipitate will form 

 which collects at the bottom of the measuring cylinder. Now pour off the supernatant 

 acetone and let the sediment stand until it is of a resinous consistence. Now dis- 

 solve 0.3 gram in i c.c. of ether and then add 9 c.c. of methyl alcohol. This gives the 

 stock antigen solution which is crystal clear. 



In using this antigen solution for the Emery or Noguchi test we dilute i c.c. with 

 9 c.c. of salt solution. This opalescent, working, antigen emulsion should be made up 

 fresh on the day of preparing the tests. 



