THE PHENOMENA OF ADSORPTION. 443 



been objected to by Sachs and Bauer * who maintain integrally 

 the opinion that was advanced by Ehrlich and his collaborator. 

 We feel led, therefore, to return to this question, which appears to 

 us to present more interest than might at first be presumed, on the 

 general problem of the action of sera and particularly on certain 

 of their practical applications. 



We may recall the facts briefly. Ehrlich and Sachs noted that 

 guinea-pig red corpuscles remain intact in fresh horse serum, but 

 are readily hemolyzed by a mixture of this serum with bovine 

 serum that has previously been heated to 56 degrees, which fact 

 gives rise to the supposition that there is a strong amboceptor in 

 bovine serum which allows the corpuscles to fix horse alexin and 

 be hemolyzed by it. But Ehrlich and Sachs found in addition that 

 if the corpuscles are placed in contact with heated bovine serum 

 and subsequently centrifugalized to remove this serum, and fresh 

 horse serum is then added, no hemolysis appears. It would 

 seem as if the bovine sensitizer required the presence of the 

 horse alexin in order to become fixed on the corpuscles. A fact 

 which seems to confirm this idea is that heated bovine serum that 

 has been previously treated with a large quantity of guinea-pig 

 corpuscles (which latter are then removed by centrifugalizing) 

 does not act as if it had been deprived of this amboceptor. It 

 is able, indeed, to form a hemolytic mixture with fresh horse 

 serum, which destroys fresh guinea-pig corpuscles. At least this is 

 Ehrlich and Sachs' interpretation of the experiment. This opinion 

 is translated into words which conform better with their theories 

 by saying that the cytophilic group of the bovine amboceptor is 

 not able to react with the corpuscle unless the complementophilic 

 group has previously satisfied its affinity for alexin. The mutual 

 relation between corpuscle, alexin and sensitizer would seem, in 

 the present instance to be unusual because, in dealing with the 

 majority of hemolytic sera, we find that the corpuscles absorb 

 the sensitizer without the presence of alexin. 



Bordet and Gay in their study on this subject were led to quite 

 different conclusions. Bovine serum possesses, in their opinion, 

 distinct properties which are, however, quite different from those 

 noted by Ehrlich and Sachs. According to Bordet and Gay, there 



* Arbeiten ans dem K. Inst. fur exper. Therapie, 1907. 



