METHODS HI-' SERO-DIAGNOSIS. 201 



resembled that of the bacteriolytic serum before-mentioned, inas- 

 much as the hemolytic serum thus prepared could be inactivated 

 by heating to 55 ° C, but could be reactivated by the addition of 

 fresh serum; and, further, the action was seen to be almost 

 completely specific, the dissolving action being most marked on 

 the corpuscles of the sheep, though it might be noted in a lesser 

 degree when the blood of an animal of closely-allied species, such 

 as the goat, was used. 



After the production of bacteriolytic and hemolytic sera had 

 been established, other workers found that they could produce 

 other cytolytic sera by using for purposes of injection, instead 

 of bacteria or red blood cells, the cells derived from certain other 

 parts of the body. Thus, for instance, a leucolytic serum acting 

 on the leucocytes was obtained by using either lymphatic glands 

 or blood leucocytes as antigen, a spermatolytic serum, by injecting 

 spermatozoa from a bull into a guinea-pig, and a tricholytic serum 

 in response to injection of ciliated epithelium. Organolytic sera 

 were also sought for, and certain of them produced, which had 

 a direct effect on the organ against which they were prepared, 

 following introduction into the body of an animal of the same 

 species as that from which the organ was derived ; and, in some 

 cases, though the reaction was specific as far as the species of 

 animal was concerned, it was not anatomically so ; thus a nephro- 

 lytic serum prepared against kidney substance could also be 

 hemolytic for the red blood cells, and also leucocytic, as well as 

 being lytic for the kidney cells, since, in injecting the kidney 

 emulsion into animals, to produce the serum, there was unavoid- 

 ably injected with it a certain quantity of blood. Nevertheless, 

 a hepatolytic serum was obtained by Delezenne in injecting dog's 

 liver into a duck, and a gastrolytic serum for the gastric mucosa 

 was obtained by Bebes and Bolton, which serum could cause even 

 perforation of the stomach wall. Thus, it will be seen that the 

 formation of lysins is a fairly general process, and not necessarily 

 only seen following the injection of bacteria or red blood cells. 



It may be noted here that of Hemolysins we recognise two 

 varieties. Thus, when in an animal of one species a hemolysin 

 is formed for the red cells of an animal of another species, we 

 speak of it as a hetero-hsemolysin ; but Ehrlich found that an 

 iso-haemolysin could be produced in an individual of one species 

 by injection of blood of another individual of the same species, 

 in the case of goats. 



These facts are of immense practical importance, for, in the 

 production of certain anti-sera, for instance, horse-sickness anti- 

 serum, in which the blood containing the virus of the disease is 

 transfused from one equine into another, it was found by Theiler 

 that certain individuals formed these isolysins. It was found 

 also that not alone were isolysins produced by using animals of 

 the same species, but also those of closely-allied species, such as 

 the horse, and ass, and also their hybrid, the mule. 



Thus individual horses hyperimmunized with horse or mule 



