578 EXPERIMENT STATION RECOED. 



ties, very small doses being fatal in many cases. Heating for one-half hour 

 at 100° C. does not destroy their activity. 



" In their anaphylactic power these ' natural proteoses ' differ sharply fi'ora 

 proteoses obtained from animal proteins by digestion with enzyms or by chem- 

 ical hydrolysis, such artificial products being almost, if not entirely, nonanaphy- 

 lactogenic. Furthermore, those products of hydrolysis which result from 

 heating vegetable proteins with acids, with water under pressure, or by peptic 

 digestion, have, so far as we have tested them, no anaphylactogenic properties. 

 From these facts it would seem that the vegetable ' proteoses ' belong to a group 

 of proteins which are chemically different from any heretofore recognized. 

 They resemble highly soluble native proteins in their anaphylactogenic capacity, 

 and are probably quite as complex in their chemical constitution. Their desig- 

 nation as ' proteoses ' is consequently improper. 



" This differentiation of so many of these ' proteose ' preparations from the 

 other proteins in the same seed is a striking example of the fact that speci- 

 ficity of the anaphylaxis reaction is not dependent on biologic origin but on 

 chemical constitution. . . . 



"The results described in this paper demonstrate that anaphylaxis furnishes 

 a useful means for determining the purity of protein preparations obtained 

 from plant extracts, in so far as contamination with the other proteins of the 

 same seed is concerned." 



Inhibitory action of heterologous protein mixtures on anaphylaxis, J. H. 

 Lewis (Jour. Infect. Diseases, 17 (IfUo). Xo. J, pp. 2-}/-~'58K — Experimental 

 data indicate that a protein which will produce a marked anaphylactic sensi- 

 tization when injected alone into a guinea pig will fail to do so if injected 

 together with, or 24 hours after, a much larger amount of another protein. 



" These results may be explaine<l by the conception that the number of re- 

 ceptors in the body that can unite with a foreign protein is limited. The 

 inhibiting protein, if present In large amount, combines with all, or almost all, 

 of these receptors. Hence, another protein injected with It, or after it, is 

 prevented from being combined in sufTiciont amount to stimulate the active pro- 

 duction of antibodies. And when a large amount of protein is injected with 

 or after a sensitizing dose of immune serum, the combination of the latter with 

 the cell receptors, which is necessary for passive sensitization, is prevented in 

 the same way." 



On the formation of specific proteolytic ferments iu response to the 

 parenteral introduction of foreig'n protein. A. E. Taylor and Florence Hul- 

 TON {Jour. Biol. Chem., 22 (1915), No. 1, pp. 59-61). — From experimental data, 

 using the protamin salmin, it was demonstrated that the rabbit does not form a 

 protective ferment in response to the injection of the particular protein used. 



" This result does not prove that a protective ferment is not formed in re- 

 sponse to the incorporation of placental protein. But it does indicate definitely 

 that the dogmatic statement that the l)ody responds with protective ferments to 

 the injection of foreign proteins as a class reaction can not be maintained." 



Results of the investigation of defensive ferm.ents by the simultaneous 

 application of different methods. E. Abperhalden (Fermentforsch., 1 (1914^, 

 A'O. 1, pp. 20-32, fig. 1). — Experimental data of results obtained by the nin- 

 hydrin, microamino-nitrogen, and total nitrogen determinations in the dialyzate, 

 optical, and interferomotric methods are recorded. The results are not dis- 

 cussed in the present paper. 



The •" interferometric method " for the study of defensive ferments, P. 

 Hirsch (Fermentforsch.. 1 (19L'f). Xn. 1, pp. 33-46. pi. 1. figs. 7).— The appa- 

 ratus and procedure of the method are described in detail. 



