SENSITIZING ANTIBODIES 299 



demonstrate the presence of immune bodies in various sera. (See 

 p. 315.) 



It should be noted that this method, if valid, must presuppose 

 the identity of the hemolytic and bactericidal complement in the 

 activating serum. 



Complement fixation will be more - extensively discussed in the 

 section dealing with the Wassermann reaction. 



WL. .Complement 



I Together a* 4 I I HaemolyKe 

 StiphiHtic present Aiwl>oceptor 



_ _ _ Jmmune or ? or 1 37.SO C. 



antibody not ^ 



f for one Hour 



<s.tf| Red blood cell 



If (2) present, no haemolysis. 

 If. (2) not present, haemolysis. 



FIG. 38. SCHEMATIC REPRESENTATION OF COMPLEMENT FIXATION IN THE BORDET- 

 GENGOU REACTION, AS CONCEIVED BY EHRLICH. (This scheme is given 

 because it aids in understanding the process, but must not be taken to repre- 

 sent the true manner of union in which the complements react.) 



The Specificity of Hemolysins. In the sections preceding we 

 have seen that the blood cells of one animal, injected into an animal 

 of another species, give rise to a hemolytic substance in the blood 

 serum of the second animal, which is strictly specific for the variety 

 of cells injected. Such hemolysins, when produced in one animal 

 against blood cells of another species, are spoken of as heterolysins. 

 In studying the nature of hemolysis, Ehrlich and Morgenroth 56 now 

 discovered that hemolysins could also be produced if an animal were 

 injected with red blood cells of a member of its own species. Such 

 hemolytic substances they called isolysins. In their experiments they 

 injected goats with the washed red blood corpuscles of other goats 

 and found that the serum of the recipient developed the power of 

 causing hemolysis of the red blood cells of the particular goat whose 

 blood had been used for injection. It did not, however, possess the 



59 Ehrlich und Morgenroth, Berliner klin. Woch., xxi, 1900. 



