demonstrated that the action of tetanolysis (which is an 

 antigen) has to do with lipoid substances, and that 

 alcohol- soluble lipoids inhibit the action of tetano ly- 

 sis; thus confirming Noguchi's findings. Landsteiner (4) 

 found that ether extracts of red blood corpuscles were 

 capable of neutralizing tetanolysin. He also showed that 

 ether- soluble lipoidal substances were involved in serum 

 hemolysis. Bang and Forsmann (5) found that hemolytic 

 activity was due to lipoid substances in the stroma of 

 the red blood cells. These lipoid substances were ob- 

 tained by extraction of the cells with ether. Upon 

 analysis they found the extracted material to be composed 

 of lecithin, cholesterin, a phosphatid and a cerebroside. 

 This material, when used as an antigen and injected into 

 susceptible called forth the production of hernolytic 

 amboceptors. Working with various serological reactions 

 Kyes (6) (7) demonstrated that lecithin was the ingre- 

 dient which played the part of complement. Sachs (8) 

 studying hemolytic reactions, determined the importance 

 of lecithin in hemolysis. Pick (10) obtained a precipo- 

 tinogen by trypsin digestion of egg albumin, and he was 

 unable to demonstrate protein in such an antigen. Some 

 workers confirmed this finding, while others were 

 unsuccessful. 



The results obtained by these workers have not gone 

 unchallenged. Nor does their work necessarily indicate 

 anything concerning the chemical nature of antigens. It 

 has been of value, however, in demonstrating the fact 

 that there is a relation between fats and lipoids, and 

 antigens. As to what this relation consists of has been 

 quite obscure, but the evidence is strongly in favor of 

 the theory that serological reactions are manifestations 

 of changes in surface tension and molecular attraction, 

 and not true chemical reactions according to Ehrlich's 

 idea. 



The chief objection to the antigenic nature of fats 

 and lipoids has been that the investigators overlooked 

 the possibility of a protein constituent being present. 

 Thus the other extract, or other extracted material, 

 might have contained protein material unsuspected by the 

 workers. Furthermore, the antigens may have been not in 

 a pure lipoid state, nor in a pure protein state, but 

 rather in the condition of a complex conjugated lipo- 

 protein which perhaps was taken up by the solvent. Thus, 

 in their studies on* anaphylaxis, Pick and Yamanouchi (11) 

 used, as antigens, alcoholic extracts of horse serum. 

 This extract was evaporated and redis solved until it gave 

 a negative biuret test. They were successful in using 



