HOWARD T. KARSNER 971 



seeds," and beta nucleoproteins remained antigenic after heating. Besredka' states 

 that if a coagulable protein be diluted so as to prevent coagulation it is antigenic after 

 heating to 120° C. Rosenau and Anderson^" showed early in their work that if the 

 protein be heated in the dry state and redissolved it will resist temperatures of 170° C. 

 for ten minutes. Falk and Caulfield^ state that a pure protein acts best as a sensitizer 

 when it is on the acid side of its isoelectric point. 



Different proteins, ordinarily regarded as antigenic, may under identical condi- 

 tions not be equally anaphylactogenic. Manwaring'' and his colleagues have found 

 that in the dog attempts at sensitization with egg white, goat serum, and horse serum, 

 injected under the same conditions in different individuals, resulted only in sensitiza- 

 tion by the horse serum. 



The suggestion that lipoids may act as anaphylactogens failed of confirmation in 

 the hands of White,s and no work since then is sufficiently convincing to alter this 

 conclusion. Such reactions as have been elicited were probably due to adsorbed 

 proteins. Although certain polysaccharides are immunologically specific (Heidel- 

 berger),^ they have not been shown to act as anaphylactogens. The substance pre- 

 pared by Tomcsik'' may be an exception but is not entirely non-nitrogenous. 



The various reactions to drugs are apparently the result of idiosyncrasy rather 

 than acquired sensitization. The studies of Pilcher and Sollmann^ with morphin show 

 no change in the cutaneous sensitiveness of addicts. The deleterious effects of highly 

 complex arsenicals and mercurials, as well as other drugs given intravenously, are 

 to be regarded as anaphylactoid. 



The amount of protein necessary for sensitization is extremely small. Rosenau 

 and Anderson were successful in guinea pigs with o.oooooi-cc. horse serum and Wells 

 with 0.00000005-gm. crystallized egg albumin. The sensitization was slight and the 

 shock dose not fatal. Larger doses are necessary with other animals, but the mini- 

 mum sensitizing dose for man is not known. White and Avery^ found that the sen- 

 sitization increases, up to a certain point, with the size of the sensitizing dose. In a 

 general way, the smaller the sensitizing dose, the larger the minimum intoxicating 

 dose. Besredka states that larger doses increase the length of time for the appearance 

 of sensitization. Lewis" has shown that simultaneous injection of large amounts of 

 one serum and small sensitizing doses of another will interfere with sensitization by 

 the latter serum. 



' Besredka, A.: Anaphylaxis and Anlianaphylaxis. St. Louis: Mosby, 1919. 

 ^ See Rosenau, M. J., and Anderson, J. F.: loc. cii. 



3 Falk, I. S., and Caulfield, M. F.: Proc. Soc. Exper. Biol. b° Med., 20, 199. 1923; J. Immunol., 

 8, 239. 1923. 



■f Manwaring, W. H., Marino, H. D., McCleave, T. C, and Boone, T. H.: Proc. Soc. Exper 

 Biol. 6° Med., 24, 650. 1927. 



s White, B.: J. Med. Research, 30, 393. 1914. 



^Heidelberger, M.: Chem. Rev., 3, 40^. 1927. 



'Tomcsik, J.: Proc. Soc. Exper. Biol, b' Med., 24, 812. 1927. 



* Pilcher, J. D., and Sollmann, T.: Arch. Int. Med., 33, 516. 1924. 



9 White, B., and Avery, O. T.: /. Infect. Dis., 13, 103. 1913. 



'"Lewis, J. H.: J.A.M.A.j'jt, 1342. 1921. 



