The experiments here described indicate that the peptone fractions can alter the different blood elements in such a manner as to affect their immunological reactions. This power is not possessed by all the peptones equally, either qualitatively or quantitatively. If we regard the phenomenon of hemolysis by immune serum in the light of a biochemical process, depending upon properties inherent in certain constituents of the serum and the red blood cells, the experiments described reveal a number of facts concerning the immunochemical action of albumoses and peptones. These substances, which depend for their separation and identification upon purely physical means, show differences in their behavior toward the elements concerned in the production of hemolysis.
Inagaki (7) has shown that the albumoses can combine with nucleohiston. It is not improbable, therefore, that some of the reactions are chemical as well as physicochemical in character.
Further studies are necessary to determine whether the reactions elicited can aid us in the differentiation of the peptone bodies, for which at present we possess but few tests. The results, however, are suggestive, and may aid in recognizing the presence of these substances in blood serum.