ON FILTRATION OF SERUM COMPLEMENT 97 



ON THE FILTRATION OF COMPLEMENT ALONG WITH 

 IMMUNE-BODY 



As already noted (p. 91), we found that immune-body 

 passes through the filter practically unchanged, and our 

 results in the present series of experiments are confirmatory. 

 We accordingly considered it a matter of interest to inquire 

 how the filtration of immune-body was affected by the 

 presence of complement. As is well known, complement 

 and immune-body when they are present in a mixture are 

 readily separable from each other by absorption methods at 

 C., but Ehrlich has suggested that they probably unite at 

 a higher temperature, the supposed amboceptor action of the 

 immune-body coming into play. Now if this were so, we 

 should expect that the immune-body which had combined 

 with complement would be retained by the filter along with 

 the latter, and thus the amount of immune-body in the 

 filtrate would be diminished, as compared with the amount 

 when immune-body is filtered alone. In every case, however, 

 we obtained the result that even when complement is present, 

 immune-body is practically unaffected by filtration. 



In the two first experiments we have as nearly as possible 

 used corresponding amounts of immune-body and comple- 

 ment, as shown by their haemolytic doses. In the third 

 experiment a considerable excess of complement was present, 

 as we supposed that possibly by this means there might be 

 retention of immune-body. The complement (fresh serum 

 of guinea-pig) and the immune-body (serum of a rabbit 

 treated with ox's corpuscles, deprived of complement by 

 heating at 55 C.) were mixed together in the quantities 

 indicated, and the volume was made up to 8 c.c. with 

 0-85 per cent, sodium chloride solution. The mixture was 

 then filtered as described. 



EXAMPLE 1. One hundred doses of complement (hsemolytic dose, 



MUIB 



