102 INFECTION AND RESISTANCE 



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 

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

 retina of the eye developed an antitoxic power against abrin which 

 protected mice against many times the fatal dose, while that of the 

 other eye remained practically inactive. 



From these facts, as well as from other observations, it is at least 

 reasonable to believe that antibo.dy formation is by no means a func- 

 / tiqn of special organs and that many cells throughout the_body may 

 take part jn_ the process. It is of especial importance to consider this 

 in connection with the possible effects of the treatment of infections 

 by means of bacterial vaccines. If the focus of the infection can 

 possibly become also a local source of antibody production then such 

 treatment may well seem rationally founded, even in generalized 

 acute infections in which no logical basis for such treatment would 

 exist, were the production of antibodies a task for specialized organs 

 like spleen and bone marrow only. The therapeutic phases of this 

 problem are more extensively considered in a later chapter. 



It is in this fact also that we must seek the explanation of the 



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



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



