SINGLE NATURE OF HEMOLYTIC IMMUNE BODIES. 339 



The contents of the three tubes are then heated to 55 degrees for 

 one-half an hour. Hemolysis complete in all tubes. From each of 

 the tubes A, B and C are prepared three smaller tubes, each con- 

 taining 0.5 of a cubic centimeter of the stroma mixture, that is, the 

 stromata of 0.025 of a cubic centimeter of rabbit corpuscles. To the 

 corresponding tubes in each series is added the same amount of 

 fresh guinea-pig alexin, as follows : 



"A" series. Tube 1. "A" mixture 0.5 c.c. 



S. guinea-pig 0.025 c.c. 



Tube 2. "A" mixture 0.5 c.c. 



S. guinea-pig 0.05 c.c. 



Tube 3. "A" mixture 0.5 c.c. 



S. guinea-pig 0.1 c.c. 



"B" series. Tube 4. "B" mixture 0.5 c.c. 



S. guinea-pig 0.025 c.c. 



Tube 5. " B " mixture 0.5 c.c. 



S. guinea-pig 0.05 c.c. 



Tube 6. "B" mixture 0.5 c.c. 



S. guinea-pig 0.1 c.c. 



"C" series. Tube 7. "C" mixture 0.5 c.c. 



S. guinea-pig 0.025 c.c. 



TubeS. "C" mixture 0.5 c.c. 



S. guinea-pig 0.05 c.c. 



Tube 9. "C" mixture 0.5 c.c. 



S. guinea-pig 0.1 c.c. 



Contact at 37 C for 1 hour. Tubes centrifugalized. The supernatant fluid 

 of each tube is placed in a new tube containing: 



Washed rabbit corpuscles 0.025 c.c. 



S. guinea-pig > rabbit, 55 degrees 0.05 c.c. 



Resultant hemolysis is as follows: 



"A" series "B" series "C" series 



1. Marked 4. None 7. Marked 



2. Complete 5. None 8. Complete 



3. Complete 6. None 9. Complete 



In series "A" the guinea-pig alexin is left entirely free because 

 the avidity of the corpuscle-immune-body complex for alexin has 

 been entirely satisfied by the rabbit alexin. In series "B" the 

 sensitized corpuscles, subjected to the same conditions of heat and 

 serum dilution as series "A," absorb perfectly the guinea-pig alexin. 

 In series "C" we have a control, with no immune serum, which 

 leaves just as much but no more guinea-pig alexin free than does 

 series "A. " The certain conclusion from this experiment is that 

 the immune body against rabbit corpuscles is of a simple nature as 

 regards combination with one or another alexin. 



