STUDIES RELATIVE TO THE APPARENT CLOSE 



RELATIONSHIP BETWEEN BACT. PERTUSSIS 



AND B. BRONCHISEPTICUS^ 



II. COMPLEMENT FIXATION TESTS 



N. S. FERRY AND H. C. KLIX 



Research Department, Parke, Davis and Company, Detroit, Michigan 



In a previous article (Ferry and Noble, 1918) we have de- •'•'*«^x, 



scribed the cultural, agglutination and absorption reactions 

 between Bact. pertussis and B. bronchisepticus and have shown 

 that, while the two organisms are distinct, they are appar- 

 ently somewhat closely related. The most striking character- 

 istics of the organisms, according to the serological reactions, 

 were shown to be the ability of B. bronchisepticus to produce 

 an immune serum that would agglutinate both the B. bronchi- 

 septicus and Bact. pertussis antigens and the ability of Bact. 

 pertussis to produce an immune serum that would agglutinate 

 only the homologous antigen. The absorption reaction showed 

 that the B. bronchisepticus antigen would absorb from the anti- 

 bronchisepticus serum (a serum that contained agglutinins for 

 both organisms) only the B. bronchisepticus agglutinin (the 

 major agglutinin) leaving intact the agglutinin for Bact. per- 

 tussis (the minor agglutinin) . This minor agglutinin could only 

 be absorbed by the Bact. pertussis antigen. This type of an 

 agglutinin was termed by the authors a ''transitive" agglutinin. 



The present investigation was undertaken to confirm the work 

 of the previous paper through complement fixation tests and 

 to determine, if possible, the value of this test in differentiating 

 between the two organisms. 



Strains used. At first a large number of strains of each organ- 

 ism were used, the same strains as those worked with in the pre- 



1 Presented at Eighteenth Annual Meeting of the Society of American Bacte- 

 riologists, New Haven, Conn., December 27-29, 1916. 



309 



THE JOURNAL OP BACTERIOLOGY, VOL. Ill, NO. 4 



