234 CHEMISTRY OF THE JMMUyiTY JiEACTIOXS 



and hemorrhages iuto both interstitial tissue and giomerules are fre- 

 quent. Some of the lesions are due to the hemolysis, and some to the 

 associated agglutination of corpuscles, which form hyaline thrombi. 

 Pearce '•'* has found that agglutinative serum when injected into dogs 

 causes widespread necrosis in the liver, which is followed by prolifera- 

 tion of connective tissue and the production of changes resembling 

 cirrhosis. There is a marked decrease in the gl^'cogen content of the 

 liver, and of its lipolytic activity (Andrea)."^ 



COMPLEMENT FIXATION "■ AND WASSERMANN REACTIONS" 



The original principle involved in these reactions was first demon- 

 strated by Bordet and Gengou, and is essentially as follows : If a 

 specific antigen and amboceptor unite in the presence of complement, 

 the complement is then united to the amboceptor-antigen compound to 

 complete the reaction. AVhen sufficient amounts of amboceptor and 

 antigen are present the entire quantity of available complement may 

 be thus fixt, and, consequently, the mixture contains no more comple- 

 ment for further reactions. As complement does not ordinarily unite 

 v/ith amboceptors except when the amboceptors are united with their 

 specific antigens, the fact that in a given system of complement 

 -(- amboceptor -|- antigen there is no free complement, is evidence 

 of a reaction between amboceptor and antigen ; in consequence of 

 which this reaction can be used to determine the presence of a specific 

 amboceptor in a serum, by using the corresponding antigen ; or con- 

 versely, with a serum containing a known amboceptor we can detect 

 the presence in a solution of the specific antigen. The indicator of 

 the presence or absence of complement which is in universal use, is 

 the ability of the mixture to hemolyze erythrocytes in the presence 

 of the specific hemolytic amboceptor. Thus, if typhoid bacilli and a 

 typhoid antiserum which contains both complement and specific am- 

 boceptor, are mixed in proper proportions and incubated for a short 

 time, the complement will he bound to the bacilli. If we then add this 

 mixture to sheep corpuscles which have been acted ujion by an anti- 

 sheei)-corpuscle serum, from which the complement had been previously 



M.Toiir. Exp. Med., 1906 (8), 64; Jour. :\r<'d. l^seardi. IIMKI (14). .-)41. 



95 Arch, internat. pharniaeodyn., 100.5 (14), 177. 



96 Tlie roaction of "complomont fixation" must not hv confused witli tlio en- 

 tirolv distinct reaction of "coniiilemcnt deviation," a mistake very lil<ely to 

 liappen because of the careless but erroneous use by some writers of tlie latter 

 icnii ill describing tlie first-named reaction. Complement deviation (or Xeisser- 

 \\'cclisl)t"r^f j)beii()iiienon) is juoduced wlien an excess of aniboccplors is present 

 tofXetlier witli antijren and a limilcd amount of coui]d('intMi(. wliicli results in 

 absence of complement activity. The inccliaiiism of tliis reaction has not liccn 

 satisfactorily explained. 



9" Literature <riven by ^Feier, .Tahresber. d. Tmmunitiitsforscli., 1909 (4). 58; 

 Sacbs and Altmann, Kolle and Wasscrmann's llandbucli. Krfriin/unjjjsbd., 2, 1909, 

 ji. 47(>: No^iiclii. "Sciiiin Diagnosis of Svpliilis and l.uclin Head ion." I'liila- 

 dclpliia, 1912. 



