CONTRIBUTIONS TO THE STUDY OF IMMUNITY. 49 



This haemolytic property can in no way, as Metchnikoff believes, 

 be due to the introduction of erythrocytes with the injection of the 

 epithelial cells into the body of the guinea-pig, 1 which introduction 

 would then lead to the formation of a specific haemolysin directed 

 against the red blood-cells. This possibility is at once excluded by 

 the method of procedure in this experiment. For reasons of asepsis, 

 the tracheae employed were scrupulously cleansed with physiological 

 salt solution and thus all traces of blood adhering to the surface 

 were removed. The epithelium itself could not contain any erythro- 

 cytes, for it was obtained by carefully scraping the surface layer, 

 which contains no blood-vessels. Errors due to any admixture of 

 blood, therefore, do not enter into my experiments. Besides, such 

 a strong haemolytic action as is manifested by the ciliated epithelial 

 immune serum is never produced by the injection of such small 

 amounts of blood. In my experiments this action was greater than 

 that following the injection of 2 cc. of cattle blood. 



The strongest proof that the blood-dissolving property of the 

 ciliated epithelial immune serum is independent of injected blood- 

 cells is afforded by the fact that the haemolytic immune body of 

 this serum possesses greater affinity for the ciliated epithelium than 

 that specifically derived by the injection of blood. 



There is no doubt, therefore, that pure ciliated epithelial immune 

 serum possesses a haemolytic action, and that, furthermore, the 

 hsemolysin produced by epithelial cells is different from that pro- 

 duced by blood-cells. 



Moxter 2 made very similar observations on spermatozoa immune 

 serum. He found that the serum of a guinea-pig which had been 

 treated with sheep spermatozoa dissolves the blood-cells of sheep; 

 and he demonstrated that the immune body concerned in this 

 haemolysis is completely bound by the spermatozoa of sheep. 



An absolute specificity, so that, for example, the immune body 

 produced by means of ciliated epithelium is bound only by ciliated 

 epithelium, that produced by means of spermatozoa bound only by 

 spermatozoa, that directed against red blood-cells only by erythrocytes, 

 without the existence of any affinities between the immune body 

 and other cells of the same species, does not therefore obtain. 



1 Just as with guinea-pigs, it is possible, by injecting rabbits with trachea! 

 epithelium of cattle, to produce a serum haemolytic for cattle blood. 

 'Deutsche med. Wochenschr., 1900, No. 1. 



