296 INFECTION AND IMMUNITY 



toxin-antitoxin mixtures, but that marked symptoms of illness often 

 followed such injections when made into immunized guinea-pigs. Other 

 phenomena which are now regarded, a posteriori, as probably depending 

 upon the principles involved in anaphylaxis, are the tuberculin and 

 mallein reactions, fully described in another place, and the adverse 

 effects often following the injections of antitoxins in human beings, 

 conditions spoken of under the heading of " serum sickness." The last- 

 named condition has been made the subject of an exhaustive study by 

 v. Pirquet and Schick. 1 



That the injection of diphtheria antitoxin in human beings is often 

 followed, after an incubation time of from three to ten days, by ex- 

 anthematous eruptions, urticaria, swelling of the lymph glands, and 

 often albuminuria and mild pulmonary inflammations, has been noticed 

 by many clinicians, who have made extensive therapeutic use of anti- 

 toxin. It was recognized early that such symptoms were entirely inde- 

 pendent of the antitoxic nature of the serum, but depended upon other 

 constituents or properties peculiar to the antitoxic serum. Moreover, 

 symptoms of this description were by no means regular in patients in- 

 jected for the first time, but seemed to depend upon an individual pre- 

 disposition, or idiosyncrasy, v. Pirquet and Schick, however, noticed 

 that in those injected a second time, after intervals of weeks or months, 

 the consequent evil effects were rapid in development, severe, and 

 occurred with greater regularity. Many of the phases of such " serum 

 sickness" are still obscure, since experimental conditions can not be 

 controlled, and many modifying factors can not be excluded in observa- 

 tions made upon human beings, and the grouping of the above conditions 

 with the phenomena of anaphylaxis is still tentative. 



The fundamental observations from which our present knowledge of 

 anaphylaxis takes its origin are those made in 1898 by Hericourt and 

 Richet, 2 who observed that repeated injections of eel serum into dogs 

 gave rise to an increased susceptibility toward this substance instead 

 of immunizing the dogs against it. Following up the lines of thought 

 suggested by this phenomenon, Portier and Richet 3 later made an in- 

 teresting observation while working with actino-congestin a toxic 

 substance which they extracted from the tentacles of Actinia. This 



^v. Pirquet and Schick, " Die Serum Krankheit," monograph, Leipzig and Wien, 

 1905. 



2 Hericourt and Richet, Compt. rend, de la soc. de biol., 53, 1898. 



s Portier and ^Richet, Compt. rend, de la soc. de biol., 1902; Richet, Ann. de 

 1'inst. Pasteur, 1907 and 1908. 



