HEMOLYSIS AND PHAGOCYTOSIS OF RED BLOOD CORPUSCLES 7 



was much less sensitive to the action of heat and other injurious 

 influences than was the alexine. 



The next advance was made by EhrHch and Morgenroth, who 

 showed that the substance sensibilisatrice of Bordet could fix itself on to 

 red blood cells without producing haemolyis, which was brought about 

 by a thermolabile substance, the alexine of Bordet. 



The substance sensibilisatrice of Bordet, they termed the amboceptor; 

 to the alexine, they gave the name complement, and showed that the 

 latter did not join on to the red blood cells directly, as Bordet supposed, 

 but probably fixed itself on to the amboceptor, which acted as a 

 connecting link between the red blood cells and the complement, and 

 not as a mordaunt, making the red blood cell more susceptible to the 

 action of the alexine, which was the view of Bordet. 



Revised views of Metchnikoff. 



Metchnikoff now accepted the view of the duality of these substances, 

 but proposed, for the sake of clearness, to use the term fixateur instead 

 of amboceptor or substance sensibilisatrice, and the term cytase instead of 

 complement or alexine. 



The point, however, which mainly appealed to Metchnikoff was 

 whether the substances producing haemolysis had any relationship to the 

 phagocytes, and he turned again to the question of the origin of the 

 cytase or alexine, formulating the belief that the macrocytase present 

 in the macrophages of the lymph glands, pancreas aselli and spleen 

 was also to be found in the mononuclear leucocytes of the blood, lymph, 

 and exudates, and that it was identical with the hsemolytic cytase of the 

 blood serum. The grounds for his belief were the following : — 



(i) If one immunised a guinea-pig with the blood of a goose, and 

 then injected some goose blood into the peritoneal cavity of the guinea- 

 pig, the alien red corpuscles were quickly haemolysed without a definite 

 phagocytosis taking place. If one examined the exudate resulting 

 from such a procedure, one found but few leucocytes, and even those 

 were in a state of inactivity, being non-mobile, clumped together, and 

 unable to engulf foreign bodies. They were, in fact, undergoing a process 

 of dissolution, which Metchnikoff termed phagolysis. According to 

 Metchnikoff, it was possible to prevent the occurrence of phagolysis by 



(307) V I 



