40 Artificial Haemolysins 



Lower Animals. 



Friedenthal was unable to demonstrate the existence of any haemo- 

 lytic action on the part of the blood of Crustacea (Cancer pagurus), 

 Oligochaeta (Arenicola piscatorum), or Sea-urchin, when these were 

 brought in contact with the blood corpuscles of the gull (Larus argen- 

 tatus) and rat. 



II. The Effects of Artificial Haemolysins upon tlie Red Blood 

 Corpuscles of different Animals in corpore and in vitro. 



The demonstration of artificial haemolysins dates from the discovery 

 of Belfanti and Carbone (vui. 1898) who found that they were formed 

 in the serum of animals treated with a foreign blood. They injected 

 large amounts of rabbit blood intraperitoneally into the horse and found 

 the serum of the horse to become highly toxic to rabbits. Similarly, the 

 serum of a dog, treated with rabbit blood, became toxic for rabbits. 

 Such sera were not toxic for the animals yielding the antisera, very 

 slightly so for other animals than those which yielded the blood injected. 

 Bordet subsequently showed that the toxic action of the serum of 

 treated animals corresponded with its haemolytic power in vitro upon 

 the particular species of corpuscles with which the animal had been 

 treated. 



Ehrlich and Morgenroth (1899) treated a goat with sheep's corpus- 

 cles and found its serum to become haemolytic for the corpuscles of the 

 sheep, although the animals are so closely allied. They subsequently 

 (vi. 1901, p. 8, repr.) found that a rabbit treated with ox corpuscles 

 developed a serum which was haemolytic for the corpuscles of the goat 

 and sheep, as well as those of the ox, although the haemolysin acted less 

 on the goat corpuscles than on those of the ox. This demonstrated 

 a similarity but not an identity between these corpuscles of Bovidae. 

 Similarly, a rabbit treated with goat corpuscles gave haemolysins for 

 goat and ox corpuscles, acting less on the latter. They explain that the 

 specificity of the immune-body formed in the blood-treated animal is 

 not to be confused with the conception of species held by systematists 

 in botany or zoology. All those elements will be affected by an immune- 

 serum which have receptors corresponding in type to that of the original 

 element injected, and consequently the influence will be most marked 

 where there are most receptors belonging to the common type. This 

 view also applies to the corresponding results obtained with precipitins. 



