ROLE OF INFLAMMATION 1 65 



ot bacterial jjioducts brings about an exudative inflammation. 

 The type of inflammation observed, ho^vever, does not stiggest to 

 them a state of previous sensitization to the substances in the 

 bacterial preparations. My o^vn observations reported in a pre- 

 \ ious chapter, also exclude the possibility of previous sensitization 

 to bacterial substances being resj^onsible for the state of reacti\'ity 

 (p. 41). 



The histological studies of Karsner and Moritz on the local reac- 

 tion follo^ving the intravenons injection sho\ved extidative inflam- 

 mation ^^■hich diflered from the primary reaction in increased 

 severity and marked damage to blood \ essels. These authors believe 

 that the increased se\erity may be due to concentration of the in- 

 jurious agent at the site of inflammation determined by the {pre- 

 paratory local injecti(jn. As already discussed, an asstniiption of 

 the sort is strongly contradicted ])y the experiments on the lack of 

 preparatory potency on the part of a large group of non-bacterial 

 substances, and by other facts just presented. According to the au- 

 thors themselves, the exudation catised by the prej^aratory injec- 

 tion alone is edema, infdtration of leucocytes and large mono- 

 cytes. The primary vascular injiuy, ho^vever, is morphologically 

 demonstraljle only in a fe^v sections, notably those from periar- 

 ticular structures. In contrast to this, the intravenous injection 

 of acti\e principles causes increased cellular infiltration, necrosis 

 of the exudate, phagocytosis of cell debris, dilatation of vascidar 

 avails and severe hemorrhage. Healing is due to granulation and 

 cicatrization. Karsner and Moritz employed bacterial filtrates con- 

 centrated by the method of Ecker and Rimington. According to 

 Ecker and Welch (1930) , the bacterial filtrates thirs prepared are 

 responsible for severe primary inflammatory reactions, i.e., pro- 

 noiniced erythema, large indurated s^velling, etc. These primary 

 reactions, in part at least, may be responsible h)r the se\ere 

 exudative inflammation follo^ving the primary reaction recorded 

 by Karsner and Moritz. Severe and confusing primary reactions 

 were also noticed by Apitz in some of his experiments ^vith fil- 

 trates of B. coli cultiues in synthetic mediimi employed l^y Ecker 

 and Welch. 



Apitz (1933) compared the histological manifestations follow- 

 ing the preparatory injection alone and h)ll()\\'ing the combined 

 preparatory and provocati\'e injections of active principles derived 

 from various microorganisms. He found that there existed only a 

 Cjuantitative difference between the intensity of reactions elicited 



