NON-SPECIFIC COMPONENTS IN S. PARATYPHI A 



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contain antigen a. This agglutination probably represents a 

 slight residue of the normal flagellar antigens of the species. 

 Phase 4 shows evidence of a slight serological relationship to 

 phase 3 and to the non-specific phases of other types, otherwise 

 it is unrelated to the known antigens of the Salmonella. 



The phases were further examined by agglutinin absorption. 

 The results of these tests confirmed the agglutination tests and 

 need not be given in detail. When absorbed serums were used 

 the cross reactions between the four phases were no longer evident. 



Figures indicate highest dilution at which agglutination occurred. 

 "0" indicates no agglutination at dilution of 1 to 200. 



Furthermore, the absorption of serum derived from one phase by 

 organisms of another did not result in an appreciable reduction 

 of the titre of the serum for the homologous phase. Absorption 

 of serum derived from phase 3 of one strain by phase 3 organisms 

 of a second strain resulted in a complete removal of agglutinins 

 from the serum. This was also true of phase 4. The non-specific 

 components (phase 2) derived from all the cultures were closely 

 related but not identical. This will be discussed below. 



While the variants isolated from the various cultures of S. 

 paratyphi A were similar, the variational tendencies of the cultures 

 differed. When the organisms were inoculated into semi-solid 



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