r.)Il] mi Phi/sini} Chnnixfru mnl llie Por/niir af Tmiiuiiiifij. 23o 



it appeared to be possible to })reparc antibodies as^ainst antibodies 

 themselves, which are all constituents of iniinuiie sera. Thus, 

 for instance. Bash ford prepared an antibody against antiricin, the 

 so-called anti-antiricin. The school of Frankfort prepared anti- 

 inunune bodies and anti-alexins, and so on. Recent investigations 

 make it probable that this new anti-action is due to a precipitin 

 against the injected innnune serum, which precipitin, when mixed 

 with this innnune serum, gives a precipitate. As is the case with 

 many precipitates this carries down with itself the large part of the 

 dissolved bodies which occur in small quantities in the serum. It 

 thereby takes away the small quantities of immune-bodies, of alexins, 

 or generally of antibodies contained in the antigenes, i.e. immune 

 sera. 



Evidently this is a kind of diversion of alexin. Gay therefore 

 raises the objection against the explanation of Neisser and Wechsbcrg 

 concerning their experiments of the diversion of alexin by means of 

 immune bodies (against bacilli). Gay is of the opinion that the 

 injected culture of bacilli contains many albuminous substances, which 

 after their injection caused the production of specific precipitins in 

 the immune serum. Gay supposes that it was these precipitins 

 which caused a precipitate with the fluids accompanying the bacteria 

 in Neisser's and AVechsberg's experiments, and that this precipitate 

 " absorbed " the added alexin, so that it is by no means proved that 

 the disappearance of the alexin was due to the presence of great 

 quantities of immune body binding the alexin. Gay was probably 

 led to this criticism because the explanation given by Neisser and 

 Wechsberg is in many details inconsistent with common laws of 

 chemistry. If the bacteria, as in my corresponding experiments with 

 red blood-corpuscles, had been freed from the accompanying 

 albuminous substances by washing carefully, then the diversion of 

 alexin by means of the immune liody would have been proved (see 

 above, IX.). 



Gay has made similar experiments with red blood-corpuscles 

 (0 • 05 c.c.) from an ox, but he added half the quantity of ox-serum, 

 freed from alexin by heating to 55°. With these he mixed a given 

 (quantity (0M)33 c.c.) of alexin (normal serum from rabbits), and 

 varying quantities of serum from a rabbit, immunized with red 

 blood-corpuscles from an ox. Then he added so much isotonic salt- 

 solution that the total volume was 2*6 c.c. He observed a very 

 strong diversion of the alexin, so that the hemolysis was complete if 

 the added quantity of immune serum was between O'l and O'Sc.c. 

 With 1 c.c. of immune serum the hemolysis was weak, and with 

 2 c.c. or more it was inperceptible. 



This method of determining the presence of a precipitate by 

 means of its aptitude to absorb alexin is much more sensitive 

 (about 100 to 1000 times) than the observation of the precipitate 

 itself. It has therefore been used for discriminating the species 



