Wright. — Anticomplementary Properties in Serum Reactions. 485 



This antigen, if acourately and carefully prepared, shows little inhibitory 

 action upon the complement used : it is immaterial whether the heart is 

 diseased or not ; it should not, however, be decomposed, otherwise certain 

 substances soluble in alcohol may be extracted which are in action inhibitory 

 to complement. 



One such antigen was prepared from a human heart removed at 

 autopsy thirty-six hours after death and while not obviously deconi' 

 posed. The resulting preparation deviated 0-75 minimum haemolytic doses 

 (M.H.D.) of complement. The use of antigen prepared from guinea-pig 

 heart was not found to be satisfactory, owing to a similar marked anti- 

 complementary action. 



Anticomplementary Reaction of Human Sera. 



Normal human-blood sera show, in the majority of cases, certain anti- 

 complementary properties. In a seiies of tests carried out to determine 

 the inhibitory power towards complement it was found that with a number 

 of normal sera the average deviation of complement was 0-5 M.H.D. In 

 conjunction with these tests the sera were also quantitatively examined to 

 ascertain what, if any, complement-deviation occurred in the presence of 

 the antigen prepared as noted above, such antigens having been found 

 to be non-inhibitory ; it was found that the average deviation of comple- 

 ment towards such negative sera was 0-75 M.H.D. 



It is thus evident that the normal subject contains in the blood small 

 amounts of antibodies, similar to, and having complementary deviation- 

 properties identical with, the antibody upon which the Wassermann 

 reaction depends for its specificity. 



Of course, in the actual determination of the Wassermann reaction 

 the controls adequately secure the true interpretation of the reaction, and 

 allow for the small amounts of inhibitory antibody, as well as the anti- 

 complementary properties of the patient's serum. The specificity of the 

 Wassermann reaction depends upon its quantitative and not its qualitative 

 determination. 



Browning's* observation that the blood-serum of the normal rabbit 

 gives a positive Wassermann reaction is confirmed by the writer's experi- 

 ments ; and, whatever interpretation may be placed upon this, it is never- 

 theless established that there are present in rabbit-sera sufficient: antibodies 

 similar to the Wassermann substance in complement-deviation power to 

 produce a positive quantitative reaction. Controls demonstrated that the 

 inhibitory properties were not of themselves merely anticomplementary, 

 but depended upon the presence of the specific antigen in addition to 

 bring about the reaction, which amounted to the deviation of as much 

 as 3 M.H.D. of complement in one case. 



In the course of the work one serum was encountered which showed 

 very strongly marked anticomplementary power, deviating by itself nearly 

 7-00 M.H.D. of complement ; later the serum from this patient showed 

 but 4-00 M.H.D. of complement-deviation ; and some months later the 

 serum was normal in complement-deviation power. This serum was so 

 abnormal that its properties were examined at the Bland Sutton Institute 

 of Pathology, Middlesex Hospital, and the residts of the investigation 

 published in a separate paper. f 



* C. H. Browning, Applied Bacteriology. 



\ E. L. Kennaway and A. M. Wright, Jour. Hygiene, vol. 18, pp. 255-59, 1919. 



