462 



THE TECHNIC OF COMPLEMENT-FIXATION REACTIONS 



3. Corpuscle control: 1 c.c. of corpuscle suspension plus 3 c.c. of 

 salt solution. 



Each tube is gently shaken and incubated at 37 C. for an hour, 

 when two hemolytic doses of amboceptor and 1 c.c. of corpuscle sus- 

 pension (5 per cent.) are added to each tube except the corpuscle con- 

 trol. Tubes are shaken and reincubated for an hour or an hour and 

 a half, depending upon the hemolysis of the serum controls, after 

 which a preliminary reading is made and recorded. With partially 

 positive reactions the tubes may be centrifuged in order to read the 

 relative amounts of hemolysis, and the final reading made at once, or 

 the tubes may be placed in the refrigerator (just above freezing- 

 point) and the final readings made the next morning. 



TABLE 15. SCHEME FOR CONDUCTING A WASSERMANN REACTION 

 (FIRST METHOD) (SEE FIG. 113) 



Tubes are shaken gently and incubated at 37 C. for an hour, after which two 

 hemolytic doses of amboceptor and 1 c.c. of corpuscle suspension are added to each. 

 They are then gently shaken and reincubated for an hour or an hour and a half, after 

 which a preliminary reading is made. 



All the tubes in the rear row (upper row in table) (serum controls), the antigen 

 and hemolytic system controls, and the front tube with the negative normal serum, 

 are completely hemolyzed. The front tubes with the unknown serum and Cerebro- 

 spinal fluid and the positive serum control show inhibition of hemolysis or positive 

 reactions. 



This scheme illustrates the technic employed with an unknown 

 serum and Cerebrospinal fluid. The proper dose of diluted antigen is 

 taken as 0.4 c.c., and two doses of hemolytic amboceptor determined 

 by titration as equivalent to 0.4 c.c. of the stock dilution. 



