BLOOD GROUP ANTIGENS 



99 



(Streptose) 



(Streptidine) 



OH H 



(A/- methyl -t-glucosomine) 



Streptomycin 

 Fig. 7-10. 



that the next-to-terminal unit in the D receptor is D-glucose or a 

 similar sugar. The likelihood that the terminal unit of rutinose, 

 L-rhamnose (Fig. 7-11), is the terminal unit of the D receptor 

 is diminished by the observation that rhamnose itself does not inhibit. 



H,OH 



It is hardly necessary to mention that a knowledge of the chemical 

 structure of the D antigen could have considerable practical value. 

 It might enable us to make good anti-D agglutinins by immunizing 

 animals, which is now impossible. Injections of a nontoxic oligosac- 

 charide with high D activity into pregnant women might possibly 

 neutralize the anti-D of the maternal and fetal circulations and pre- 

 vent erythroblastosis in the infant. 



The inhibition behavior of anti-C and anti-E seems to be more 

 complicated (Table 7-8). L-Glucose has some inhibitory effect on 



