XVIII. DEVIATION OF THE ALEXIN IN HEMOLYSIS.* 



BY FREDERICK P. GAY. 



Since the observations of Neisser and Wechsbergf on the inhibiting 

 influence on bacteriolysis of too large a dose of specific immune 

 serum (previously heated to 55 degrees) when the amount of alexin 

 is relatively small, many attempts have been made to determine 

 the mechanism of this interesting phenomenon. The interpreta- 

 tion that Neisser and Wechsberg gave is well known; it is wholly 

 in harmony with Ehrlich's theory. According to these authors, in 

 a mixture of bacteria, a relatively small dose of alexin, and a 

 relatively large dose of heated immune serum, or, in other words, of 

 sensitizer (amboceptor), not all the alexin is utilized in destroying 

 bacteria. Not all the large amount of sensitizer present can be 

 absorbed by the bacteria; the excess remains in the surrounding 

 fluid and, owing to its affinity for alexin, takes up a greater or less 

 amount of this substance that consequently is of no service in 

 producing bacteriolysis. The inhibiting effect of too much immune 

 serum would be explained as a real deviation of the complement 

 (Komplementablenkung) by the excess of sensitizer not combined 

 with the bacteria. This hypothesis, to be sure, has neither been 

 experimentally proved nor refuted. It is by no means necessary to 

 accept it, as it is based on a supposition that has never been proved 

 experimentally, namely, that the sensitizing substance can fix 

 alexin even when uncombined with bacteria. It must be admitted 

 that certain defenders of the hypothesis, notably Lipstein,f have 

 been able to reply to certain objections that have been raised to it, 

 without, however, bringing forward any really definite proofs of its 

 correctness. The inhibiting effect of an excess of immune serum 



* La deviation de 1'alexine dans 1'hemolyse. Annales de Tlnstitut Pasteur, 



XIX, 1905, 593. 



t See Studies on Immunity, Ehrlich-Bolduan, John Wiley & Sons, p. 120. 

 J Lipstein, Ehrlich-Bolduan, Wiley & Sons, p. 132. 



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