JOINT ACTION OF SEVERAL AMBOCEPTORS. 631 



haemolysis of guinea-pig blood, but acting in quite another manner 

 in the haemolysis of the prepared ox blood. 



Another difference between the two phenomena is presented 

 by the following: If prepared ox blood-cells are successively digested 

 with horse serum and inactive ox serum, no haemolysis occurs. This 

 is entirely analogous to what is observed with guinea-pig blood- 

 cells. While, however, when a^ large amount of horse serum has 

 been used, the guinea-pig blood-cells are resistant to the combined 

 action of horse serum and inactive ox serum, this is not the case 

 with the prepared ox blood. Before going into details, however, 

 it may be well to make certain general observations concerning the 

 behavior of the components in the haemolysis of prepared ox blood. 

 Thus it was found that to be impossible to replace the inactive ox 

 serum by hog or rabbit serum. The same was true for inactive 

 sheep serum, 1 whereas inactive goat serum in conjunction with horse 

 serum acted like ox serum though weaker. 2 We also noted the effect 

 of thermic influence on the components of horse serum 3 and found 

 that the ox serum could be heated for half an hour to 55 without 

 affecting its action, while on heating for half an hour to 65 it lost 

 its power to dissolve prepared ox blood in conjunction with horse 

 serum. So far as the relation of the individual components to the 

 prepared blood-cells is concerned, it was found that active horse 

 serum is robbed of its active constituent by treatment with prepared 

 blood. In fact, not only does it thereby lose its property to dissolve 

 prepared ox blood (confirming Bordet and Gay), but it also ceases to 

 dissolve guinea-pig blood in conjunction with inactive ox serum 

 (confirming the statements of Browning) . This was to be expected, 

 because in both combinations the horse serum acts as complement, 

 and a suitable amboceptor is present. In both cases, therefore, 

 the amboceptor can effect absorption of complement without giving 

 rise to haemolysis. There is another point of agreement between the 

 two combinations. Thus, despite the anchoring of horse com- 

 plement brought about by treatment with horse serum, the prepared 

 ox blood-cells do not dissolve on the addition of inactive ox serum. 



1 Active sheep serum by itself is slightly haemolytic for prepared ox blood. 

 The action is intensified, however, by the addition of horse serum. 



2 It should be remarked that in the haemolysis of guinea-pig blood the ox 

 serum can be replaced by goat serum. The mode of action is the same in 

 both cases. 



3 Ox serum? [Editor.] 



