446 Biology in America 



plement." If the liver of an unborn or newly born eliild 

 infected with sypliilis (such bodies may frequently be obtained 

 from autopsies) be extracted with alcohol a substance 

 "antigen" is obtained which has been secreted by the germ 

 of the disease, the Trepoiu'ma pallidum. This substance we 

 may designate as a'.'''*^ It likewise forms a chaiii with comple- 

 ment c in the presence of amboceptor b, which we may repre- 

 sent as a'-b-c. In the language of the bacteriologist it 

 "fixes" or "anchors" the complement. Tlie blood serum of 

 the person suspected of an infection with syphilis is also 

 heated to 133° F. to destroy its "complement." The "anti- 

 gen" is now mixed with the blood serum of the suspect and 

 a definite amount of guinea pig serum containing free 

 "complement," which has not been heated, is added and 

 the whole placed in an incubator or oven for an hour and 

 a half. If the suspect is syphilitic, his blood will contain 

 the amboceptor b, which has been developed there through 

 the presence of the germs of the disease. In this case the 

 antigen a' will combine with the complement c of the guinea 

 pig, through the medium of the amboceptor b, present in the 

 suspect's blood. If, on the contrary, the suspect is free 

 from infection no amboceptor Avill be present and the antigen 

 will not be able to fix the complement in the guinea pig's 

 serum. A definite amount of the rabbit's blood mixed with 

 the sheep's blood is now added and in the former case 

 (presence of syphilis) no reaction will occur, the complement 

 being fixed. In the latter case however (syphilis absent) 

 the complement will be free to combine with the amboceptor 

 in the rabbit's blood, the first reaction (a-b-c) will occur and 

 the red corpuscles of the sheep will be broken down with 

 liberation of their hemoglobin. 



This test, known from its discoverer as the Wassermann 

 test, is not absolutely certain, but it is efficient in probably 

 90% of the tests made. If it is repeated at intervals for 

 two years after the disappearance of all active symptoms, 

 and a negative result obtained each time, the patient may 

 with reasonable certainty be considered cured. 



There has recently died in Germany a man whose name 

 is destined to be ever bright in the annals of science. Paul 

 Ehrlich, famed for his researches on cancer and immunity, 

 the latter based upon his theory of the chemical affinities of 

 living cells, was the discoverer of a specific remedy for syphilis 

 — salvarsan or "606", successful after 605 substances had 

 been tried and failed! This remedy, a compound of arsenic, 

 is now widely used in the treatment of the "red plague." 



^ This was the original niethod. It is now known that "antigen" a 

 is non-siiecific. Hence extracts of various normal organs may be em- 

 ployed. 



