PHENOMENA FOLLOWING IMMUNIZATION 



nectomy, moreover, has been variously shown. In unpublished ex- 

 periments by the writer splenectomized guinea pigs showed no differ- 

 ence from normal animals in regard to their susceptibility to tuber- 

 culosis. And though these and similar experiments of other workers 

 with various bacteria are not entirely devoid of interest, their 

 negative results as a matter of fact have no great significance, since 

 our knowledge concerning the true function of the spleen is very in- 

 complete, and it is not impossible that on removal of this organ 

 other elements of the lymphatic system may take over its function in 

 part or as a whole. 



Removal of the spleen has not been an extremely unusual pro- 

 cedure in surgery, and there is no evidence to show that patients so 

 treated have been abnormally susceptible to infection thereafter. 



Yet, as we have seen, there seems to be an early concentration of 

 antibodies in the lymphatic organs in the course of immunization, 

 and it may well be that an association between the process and these 

 tissues exists which cannot be experimentally demonstrated with 

 absolute certainty. 



It is no less likely, however, that similar functions are exerted 

 by the cells of other organs. In fact, it is more than probable that 

 antibodies may be formed anywhere in the body and that the local- 

 ity of their production is largely dependent upon the locality in which 

 the antigen is concentrated. Wassermann and Citron 85 demonstrated 

 this by injecting typhoid bacilli into rabbits intraperitoneally, in- 

 travenously, and intrapleurally, and nine days afterward determining 

 the comparative bactericidal strength of blood serum and of aleuronat 

 exudates of pleura and peritoneum in each of the three animals. 

 Their results showed that the bactericidal titre of the intravenously 

 inoculated animal was highest in the blood serum, while that of the 

 intraperitoneally and intrapleurally inoculated animals was highest 

 in peritoneal and pleural exudates respectively. Such experiments 

 point to the possibility of a "local" immunity, that is, a production 

 of antibodies directly by the cells with which the antigen comes into 

 contact in the most concentrated and direct manner. And, indeed, 

 another isolated experiment of the same authors, alone successful of 

 a series of similar attempts, would point in the same direction. 

 Typhoid bacilli were injected subcutaneously into the ear of a rabbit 

 and the ear immediately ligated at its base and kept so for several 

 hours. After nine days the bactericidal titre of the blood serum was 

 determined and the ear amputated. An immediate and rapid drop 

 of antibody contents occurred after the amputation indicating that 

 the chief source of antibody function had been removed. More strik- 

 ing examples of the same thing are to be seen in the experiments of 

 Homer, 86 who instilled abrin into a rabbit's eye and found that the 



85 Wassermann and Citron. Zeltschr. f. Hyg., Vol. 50, 1905. 



86 Romer. Arch. f. Ophthal, 52, 1901. 



