SIGNIFICANCE OF PHENOMENON 391 



of its own (niz., B. coli culture filtrate) , (h) ^vhen the injected 

 antigen enters into combination with antibodies not related to 

 the disease but incidentally present in the animal and (c) \vhen 

 certain colloids possessing provocati\e potency are injected (agar, 

 starch) . The reactions may be, B — specific, i.e., produced by the 

 antigen related to the infection (a) ^vhen the antigen possesses ac- 

 tive principles of its own and (b) when it enters into combination 

 with antibodies actively acquired in the cotnse of the disease. The 

 specificity of the bacterial allergy, therefore, in these terms is only 

 limited to the process of formation of reacting factors through the 

 antigen -j-antibody interaction. 



It is also suggested in this chapter that the necrotic and hem- 

 orrhagic reactions of the Arthus phenomenon in man belong at 

 least in part to the domain of the phenomenon of local tissue 

 reactix'ity. The following course of events, as illustrated by the 

 studies on the phenomenon of local tissue reactivity, is suggested 

 for these cases: (1) Localization of bacterial reacting factors in 

 the sites injected Avith the animal protein; (2) sid3sequent elicita- 

 tion of reactivity by means of these bacterial factors; (j^) the 

 animal protein (serum) injected into these patients may interact 

 with previously actively acquired antibodies and form the neces- 

 sary factors for elicitation of severe lesions in the reactive sites. 

 The possible relation of the bacterial active principles of the 

 phenomenon of local tissue reactivity to spontaneous infectious 

 diseases is suggested Ijy a nimiber of facts. 



Stolyhwo dre^v attention to close histological similarity bet^veen 

 the hemorrhagic and necrotic decubital lesions of severe cases of 

 typhoid and paratyphoid fe\'er and the lesions of the phenome- 

 non. These lesions were incidental to manifestations of general 

 toxemia. The mine and sweat of some of the severe cases of 

 typhoid fever contained the active principles of the phenomenon 

 of local tissue reactivity. 



Klein demonstrated phenomenon-neutralizing antibodies in 

 human sera from meningococcus, gonococcus and typhoid infec- 

 tions. In some instances there Avas obser\ed a gradual increase 

 in the amotmt of neutralizing antibodies in the coinse of the 

 infection ^vhich reached a titer well abo\e normal expectancy at 

 the time of convalescence. In severe gonococcus infections com- 

 plicated by endocarditis, no increase in neutralizing titer was 

 observed. 



