48 Agglutinins and A^itiagglutinins 



tination\ These results have been confirmed in the main by Friedberger 

 (ix. 1901), who does not however consider that salts act chemically, for 

 he found agglutination to take place in the presence of grape-sugar, 

 asparagin, etc. 



The agreement is fairly general as to the chemical nature of the 

 reaction, both components being used up in the process, as was originally 

 observed by Gruber. In this they are similar to the other antibodies". 

 How stable the union is has not been made clear. Landsteiner (1901) 

 finds that when red corpuscles have been agglutinated with serum or 

 abrin, the agglutinin may be again obtained, after they have been 

 washed, by simply warming them in salt solution. This would scarcely 

 point to a well-established union. 



Widal {Semaine Medicate, 1897, No. 5, cited by Kraus) found that 

 tj'phoid bacilli which had been killed by exposure to a temperature of 

 56° C. were still subject to agglutination; a fact which Kraus (12, viii. 

 1897) confirmed both for the tj^phoid bacillus and that of cholera. The 

 reaction does not therefore depend upon the germs being alive. 



Agglutinins are more resistant to heat than are haemolysins or 

 bacteriolysins, withstanding a temperature of 55° C. and over; for instance, 

 Laveran and Mesnil (25, ix. 1901, p. 695) found specific Trypanosoma- 

 agglutinin to be inactivated at 63 — 65° C. (| hour), and Bordet (iii. 1899, 

 p. 243) found haemagglutinins (of rabbit treated with fowl's corpuscles) 

 to be destroyed at 70° C. in half an hour. Like the precipitins, they are 

 stable bodies, retaining their agglutinating power at times for man}- 

 months in vitro. Pick (1902, p. 21) cites Widal and Sicard (1897) and 

 Winterberg (1899) as having found the agglutinins to be precipitated 

 with the globulin fraction from serum. He has confirmed this, working 

 with typhoid-agglutinin. The latter was present in the pseudoglobulin 

 fraction, only traces (presumably impurities) being found with euglo- 

 bulin, when horse serum was examined. On the other hand in immune 

 goat, rabbit, and guinea-pig serum, the agglutinin was almost entirely 

 confined to the euglobulin fraction. Similarly cholera-agglutinin was 

 almost entirely confined to the euglobulin fraction, both in immune 

 horse and goat serum. Here again we find a similarity with otiit'r 

 antibodies (see precipitins, antitoxins, etc.). 



The significance of the agglutinins is but imperfectly understood. They may 

 persist in the serum of persons who have had typhoid fever for months and even 

 years. In some cases this would appear to be referable to a retention of these 



1 See farther Bordet (in. 1899). 



- See the investigation of Eisenberg and Volk (2, v. 1902). 



