NON-SPECIFIC COMPONENTS IN S. PARATYPHI A 475 



specific components were identical. In one group were cultures 

 228, HR and Fried; while 38250, Marta, Cal. 49, 1015, HA1, 

 HA6, WB39, Boyd and Durazzo were included in the second. 

 The differences between these two groups were evidenced only 

 by a slight residue of agglutinins remaining when the serum 

 derived from a member of the second group was absorbed with 

 a member of the first group. These residues of agglutinins did 

 not exceed 2 per cent of the original titres of the serums. The 

 differences in the non-specific components of S. paratyphi A 

 were no more pronounced than those that exist in the non-specific 

 phases of different diphasic species in which the second phase is 

 expressed as 1, 5.... The phases denoted as 1, 5... in the 

 Kauffmann-White classification are quite complex and their 

 exact relationships cannot be expressed without the use of further 

 symbols. In this connection it should be remembered that the 

 classification was designed by Kauffmann as a diagnostic schema 

 and that it does not give a complete antigenic delineation of 

 the bacilli. 



The relationships of the non-specific components of S. para- 

 typhi A to the naturally occurring 1, 5. . . phases were studied 

 by agglutinin absorption tests. It was found that serums derived 

 from 228, HR or Fried were completely exhausted of agglutinins 

 by absorption with the non-specific components of 38250, Marta, 

 Cal. 49, 1015, HA1, HA6, WB39, Boyd, Durazzo or Sendai. 

 The serums of the latter group were not completely absorbed by 

 228, HR, Fried or Sendai. None of the non-specific phases of 

 S. paratyphi A removed all the agglutinins from Sendai serum. 

 The relationships of the non-specific components of S. paratyphi A 

 and Sendai were appreciably closer than were their relationships 

 with the non-specific phases of any other type. 



DISCUSSION 



While earlier workers realized that the Salmonella group was 

 composed of a mosaic of interrelated antigens, Bruce White 

 (1926) was the first to identify these antigens by symbols and 

 thus express the relationship and divergences of different species 

 in graphic form. In addition he was the first to discuss the 



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