174 CHEMISTRY OF THE IMMUNITY REACTIOXS 



ciiliii reaction could be produced with deutero-albumose, many sim- 

 ilar non-specific reactions have been observed. Particularly the 

 sharp reaction that follows intravenous injections of killed typhoid 

 bacilli into typhoid patients has been found to result equally well if 

 colon bacilli are used, or deutero-albumose. One possible explana- 

 tion of this type of reaction is that the injected substance acts as a 

 common antigen, which causes the production of common antibodies 

 that react also with the antigens of the cause of the disease. Another 

 possibility is that the foreign protein stimulates the tissues that 

 form antibodies, presumabl.y the red marrow, so that they produce 

 not only antibodies for this antigen, but also for the antigens of the 

 specific etiologic factor of the disease that have been stimulating the 

 bone marrow previously. INIoreover, the febrile reaction, the leu- 

 cocytosis, and other phenomena, such as the antiferment index of 

 the serum ( Jobling), that injection of nonspecific protein produces, 

 may be responsible for favorably affecting the disease, rather than 

 actual antibody formation. 



An interesting illustration of the fact that whatever stimulates the 

 bone marrow may cause it to form, among other blood elements, spe- 

 cific antibodies, is furnished by the behavior of antitoxin-producing 

 horses. If a horse that has been imnuinized to diphtheria toxin is 

 bled as much as possible, it will be found to have regenerated the lost 

 antitoxin within 48 hours,*^*^ even although the last immunizing dose 

 of toxin was received long before. Also, it is stated that persons who 

 have once had typhoid, but whose blood no longer contains much 

 agglutinin, may show a high typhoid agglutinin content when infected 

 by some other organism, or after any sharp febrile attack. It is 

 highly possible that many therapeutic agents may similarly act by 

 stimulating the marrow to increased formation of specific antibodies, 

 e. g. arsenic, mercury and other metals, lieliotlierapy, hemorrhage or 

 phlel)otom.y, hot baths. 



The other aspect of specificity, i. e., the presence of several antigens 

 in a single organism, entirely distinct from other antigeus in the same 

 organism, has been repeatedly demonstrated. Besides the identifica- 

 tion of five distinct antigens in tlie hen's ogfc. mentioned previously, 

 we have the repeatedly demonstrated individuality of serum pro- 

 teins and milk casein of the same animal, and even the differentiation 

 of casein from lactalbumin in the same milk, as contrasted witli the 

 common inter-reactions of caseins from different sources,^^® e. g., cow 

 and goat. A certain but slight distinguishable specificity may be ob- 

 served between proteins from different organs of the same animal, 

 which differentiation is still sharper between the tissue proteins and 

 serum proteins of tlic }iniiii;i].^"' Sex cells esjiecially seiMu to be 



iidO'Rripn. .Jour. Palli. iiiul Had., ini.3 (18), SO. 

 4ic.Sce VorscU. Zeit. liiiiimnitiit., 1915 (24), 2()7. 

 4ifSee Salus, liiocliein. Zeit., ION (GO), 1. 



