438 THE TECHNIC OF COMPLEMENT-FIXATION REACTIONS 



1. The antigen control: Dose of antigen plus 1 c.c. of complement 

 (1 : 20) and a sufficient quantity. of salt solution. 



2. Hemolytic system control: 1 c.c. of complement (1 : 20) and 2 

 c.c. of salt solution. 



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 

 suspension (2.5 per cent.) are added to each tube except the corpuscle 

 control. 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. 110) 



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. 



