STUDIES ON ANTIAMBOCEPTORS. 



659 



making experiments on the deflection of complement, was also well 

 demonstrated by using a strong precipitating serum which had 

 previously been employed for identifying human albumin. This 

 serum was obtained from rabbits by immunization with human 

 serum, and is therefore termed "H-R-serum." Since the only 

 antiamboceptors which this serum can contain are those directed 

 against human amboceptors, it is obvious that an antiamboceptor 

 action is at once excluded if we employ rabbit amboceptors specific 

 for ox blood. We began by following the regular technique employed 

 by M. Neisser and Sachs * in their studies on the forensic blood test 

 by means of antihsemolytic action, and followed this by two parallel 

 experiments in which we varied the sequence of the reagents em- 

 ployed. The details of the three tests are as follows: 



Series A. Each tube contains 0.02 cc. H-R-serum, plus 0.05 cc. guinea-pig 

 serum, plus decreasing amounts human serum. Mixtures kept one hour at 

 37. Then 1 cc. 5% ox blood, plus 0.0015 rabbit amboceptor. 



Series B. 0.02 cc. H-R-serum, plus human serum, plus 1 cc. 5% ox blood, 

 plus 0.0015 rabbit amboceptor. After standing one hour at 37, 0.05 cc. 

 guinea-pig serum. 



Series C. 0.02 cc. H-R-serum, plus human serum, plus 1 cc. 5% ox blood, 

 plus 0.0015 rabbit amboceptor. After standing for If hours at 37, the 

 mixtures are centrifuged. Then 0.05 guinea-pig serum is added to the sedi- 

 ments. 



In series C, the mixtures were kept at 37 for 1J hours in order to furnish 

 more favorable conditions for the formation of a precipitate, and also so that 

 the conditions as to time would be the same as those in the antiamboceptor 

 experiment. In series B and C, the guinea-pig serum was kept at 37 for 

 one hour previous to mixing. 



The result of this experiment is shown in Table V. 



TABLE V. 



1 Neisser and Sachs, Berliner klin. Wochenschrift, No. 3, 1906. 



