COMPLEMENT FIXATION IN SYPHILIS 429 



Health Supplement No. 11 to Venereal Disease information. This 

 can be obtained from the Superintendent of Documents at a 

 nominal cost. Since the Public Health service plans to issue re- 

 visions of Supplement No. 11 from time to time it would seem 

 advisable for medical students, and others interested, to be on the 

 alert for such revisions. 



The antigen used in the Kolmer test is a cholesterolized and 

 lecithinized alcoholic extract of heart muscle. It is prepared by 

 extracting powdered beef-heart with acetone for 5 days to remove 

 all the acetone soluble substances since they are thought to be un- 

 desirable. The acetone extract is filtered off and discarded. The 

 dry residue is next exti*acted with chemically pui-e absolute elhyl 

 alcohol for 5 days and filtered. This filtrate is saved since it con- 

 tains tlie acetone insoluble, alcohol .soluble lipoids used in the 

 Kolmer antigen. To improve the antigen, i.e., to make it more 

 sensitive, Kolmer adds 0.2 gm. of cholesterol to each 100 c.c. of the 

 alcoholic solution of lipoids. After shaking and heating for one 

 hour in a water bath at 55° C. to aid in the solution of the 

 cholesterol it is allowed to stand at room temperature for 2 or 3 

 days and finally filtered to remove any precipitates that may have 

 formed. This cholesterolized alcoholic extract is standard stock 

 solution of antigen. 



Kolmer also prepares a neiv antigeyi which is more sensitive than 

 the above. The only difference is that the new antigen has not only 

 all of the lipoids of the first antigen but there has been added 

 to it, just before he added the cholesterol, all of the ether soluble 

 but acetone insoluble lipoids obtained from the first 4 ether ex- 

 tracts of heart muscle that are usually discarded in the preparation 

 of either Kahn or Eagle antigen. These added lipoids make the 

 new Kolmer antigen more sensitive. 



Titration of Antigen. — Both of the antigens mentioned are 

 titrated in the same way. Kolmer says that it is unnecessary to 

 titrate these antigens for hemolytic or anticomplementary units. 

 It is, however, necessary to titrate for antigenic activity. This he 

 does in accordance with the method of Boerner and Lukens. A 

 brief summary and protocol is as follows : 



He first prepares a 1 :80 dilution of antigen by adding, drop by 

 drop, 0.1 c.c. of the cholesterinized alcoholic solution of lipoids to 

 7.9 c.c. of saline, shaking between each drop. Beginning with this 



