USE OF SENSITIZED CELLS FOR NOGTJCHI TECHNIC 183 



human serum tested, we employ the 40% solution used in Noguchi's 

 technic. 



Experiments have shown that one volume of serum contains almost invariably 

 sufficient complement to haemolyze the red cells present. As a matter of fact in 95% 

 of sera one-half this amount would suffice. 



It will be noted that the amboceptor and antigen content of the 

 i to 80 tube is proportionate to that used in the Noguchi test. 



NAVAL MEDICAL SCHOOL MODIFICATION OF NOGUCHI'S TECHNIC 



There is evidence for believing that the heating of the serum to be 

 examined not only destroys about 75% of its total syphilitic antibody 

 content but may also destroy thermolabile substances which may be 

 of importance in bringing about a positive reaction. At any rate I 

 have had experience with sera where, with an absolutely clear diagnosis 

 of syphilis followed by response to therapeutic measures, there has 

 been a negative reaction with inactivated serum but a positive one with 

 unheated serum. 



For this reason I would advise that the Noguchi method be carried 

 out with inactivated serum and an Emery test also made using un- 

 heated serum. 



The Emery test is also of value as showing a quantitative relation. At the same 

 time I am convinced that it is more conservative to make a diagnosis of syphilis only 

 with inactivated serum, reserving the utilization of findings with unheated sera for 

 effect of treatment on syphilitics and for such cases as the symptomatology and 

 history of the case would indicate that a positive reaction should be obtained. 



No injury is conferred on a patient by a negative Wassermann be- 

 cause in the presence of other data treatment will not be withheld. 



A modification of the Noguchi technic, along the Emery lines, which saves time 

 and makes readings sharper is to employ sensitized red cells. To do this add to the 

 drop of patients serum and 40% guinea-pig complement and antigen in tube la, % 

 c.c. of salt solution. Also to tube ib, containing the serum and complement but 

 without antigen add 14 c.c. salt solution. Incubate for absorption of complement. 

 So soon as these tubes are placed in the incubator prepare a mixture of i% washed 

 red cells, according to the amount to be used in the number of tests to be carried 

 out, and add 2 units of amboceptor paper for each Y% c.c. of this red-cell emulsion. 

 Incubate along with the other tubes. When the period for the primary incubation is 

 completed add to each tube K c.c. of the emulsion of sensitized red cells. ^ 



Incubate again and readings can usually be made in ten to fifteen minutes and 

 give unusually clear-cut readings. 



