1 68 THE TECHNIQUE OF COMPLEMENT FIXATION. 



3. Inactive hemolysin. 



4. Red blood cells. 



In view of the above-mentioned objections, to wit, the too frequent positive results, 

 this modification although advised by divers authorities, Stern and others, should not 

 be employed. 



Not only the addition of complement, but also of immune hemolysin 

 can be discarded, because every serum normally contains hemolytic anti- 

 bodies for foreign species of blood. The contraindication for the trans- 

 fusion of foreign blood depends upon this principle. 



Accordingly, some authors advise the following schemes: 

 i. Luetic extract or its substitute. i. Luetic extract or its substitute. 



2. Inactive luetic serum ("luesreagine" + 

 hemolysin). 



2. Active luetic serum (luesreagine + com- 

 plement + normal hemolysin), one 



3. Complement. One hour in incubator. hour in incubator. 



4. Washed erythrocytes of sheep. j 3. Washed erythrocytes of sheep. 



The advantage of these modifications is supposed to exist in the omission of the 

 immune hemolysin. The preparation and preservation of this ingredient is, however, 

 technically so simple that this advantage is only theoretical. Bauer believes that this 

 change is preferable to the classical method for the reason that with the latter, the x 

 amount of normal hemolysin is always added to the constant amount of immune 

 hemolysin, thereby resulting in a different quantity of the same in each test. Experi- 

 ence has, however, shown that the faint trace of normal hemolysin never influences 

 the result of the test. At times so little normal hemolysin will exist in a patient's 

 serum that it becomes necessary to add some serum of another normal patient. Such 

 manipulations lead to new difficulties so that taken all in all, this innovation offers no 

 advantages and should therefore not be accepted. 



Brieger and Renz have recently advised the substitution of potassium chlorate for the 

 immune hemolysin. Had this been correct the biological bases of the Wassermann 

 reaction would have been undermined. Garbat and Munk have, however, shown that 

 in this modification KC1O 3 is entirely inert and that the reaction depends upon the 

 normal hemolysin in human serum against sheep's erythrocytes. 



Several workers in this field believed that it would be advantageous to 

 use a different species of blood in place of sheep's erythrocytes. 



The only suggestion which sounds theoretically correct is that of Noguchi, who 

 employs human erythrocytes and the serum of a rabbit immunized against human 

 red blood cells. In this way he attempts to exclude the x normal hemolysins, as human 

 serum possesses no hemolysins against human blood cells. 



1. Syphilis extract or its substitute. i. Syphilis extract. 



2. Inactive syphilis-serum. | 2. Active defibrinated syphilitic blood. 



3. Complement from human | (Erythrocytes, "reagine," comple- 



being or guinea-pig, [ Syp ment), one hour in incubator. 



. . . . serum. ,. . 



one hour in incubator. J 3. Immune hemolysin of rabbit (injected 



4. Immune hemolysin of a rabbit against j with human blood). 



human erythrocytes. 



5. Washed human erythrocytes. 



