Bacteriolysins 27 



The seat of origin of bacteriolysins in corpora has been studied by a number 

 of observers, and has been the subject of considerable discussion, for which reason 

 I shall not enter upon it here (see Metchnikoff, 1901 ; Pfeiffer and Marx, 1898 ; 

 Deutsch, 1899 ; Wassermann, 1899 ; Rbmer, 1902 ; and the reviews of Ritchie, 

 1902 and Aschoff, 1902). According to Pick (1902, pp. 1521) bacteriolysins are 

 contained in the euglobulin fraction of serum, this being contrary to Pfeiffer and 

 Proskauer (1896). 



That there is a difference in the specific bacteriolytic sera obtained from different 

 animals appears to be the case from the investigations of Sobernheiin (1899), who 

 found that anti-anthrax serum obtained from imiuunitied sheep was able to protect 

 sheep but not rabbits. In this case we are dealing, not with an antitoxic serum but 

 with one whose action is antibacterial. As Ehrlich (f'roonian Lect. 1900) notes, 

 Kitt had a precisely similar experience with symptomatic anthrax. It will be noted 

 that an analogous observation has been made with regard to the precipitins. 

 This would appear to be due to the complexity of bacteriolysins and precipitins as 

 compared with antitoxins, where no such differences have been noted. It may be 

 supposed that in reacting to a highly complex body the organism impresses 

 more of its own character upon the antibody which it evolves. 



Depending upon the age of an animal, its blood corpuscles will behave differently 

 both to natural and artificial haemolysins. Thus Camus and Gley (1899, p. 779) 

 found the normal haemolysiu of eel serum to be markedly resisted by the corpuscles 

 of young rabbits, and Delezenne (x. 1900, p. 702) found the corpuscles of young 

 dogs to be much more resistant to the artificial haemolysins (for dog) than those 

 of adult animals. We shall sec that the precipitins also give different reactions 

 with foetal and adult blood. 



The bacteriolysins to which reference has been made in the preceding jiages 

 constitute a class of cytotoxins essentially similar to the haemolysins. They act 

 upon bacteria. Their presence in normal blood and various body fluids was 

 demonstrated by Nuttall (1888); whereas artificial or specific bacteriolysins were 

 first demonstrated by Pfeiffer in animals immunified with the cholera vibrio. 

 The work done on the bacteriolysins has been very extensive, but it is impossible 

 to enter into the subject here at all in detail. It will suffice to say that the 

 specific bacteriolysins behave essentially as do the specific haemolysins, and that 

 they possess the same constitution. They are composed of a labile complement 

 (destroyed at 55 C., as I first showed for normal bacteriolysins) and of a stable 

 immune-body. The latter is capable of conferring immunity, as was first shown 

 by Fraenkol and Sobernheiin (1894, p. 154), on heated anti-cholera serum which had 

 lost its bactericidal properties. Wassermann (3, i. 1901) was able to neutralize the 

 complement by means of anti-complement, the latter being specific and only capable 

 of binding one sort of complement. As in haemolytic sera, agglutinins may lx> 

 present together with lysins. Pfeiffer observed the agglutinin to disappear in 

 stored immune-sera (of goat and dog treated with B. typhosui) and the immune- 

 body to persist therein. Mortens (13, vi. 1901), who cites this unpublished 

 observation of Pfeiffer, was able to confirm it on cholera immune-serum 5 years old. 

 The existence of immune-bodies in anti-microbic sera has been also proved by 

 Bordet and Oengou (v. 1901) in experiments upon the blood of animals treated with 



