BLOOD GROUP ANTIGENS 



97 



CH20H 



H OH 



Bauhinia receptor 



CH2OH 



Peanut receptor (Gy) 

 Fig. 7-9. Suggested structure of the terminal portions of three receptors of 

 the human red cell which contain galactose as a terminal monosaccharide unit 

 (Boyd, 1960). 



the terminal unit is mannose. We cannot go further than this on 

 the information now available. 



The RH Receptors 

 In my laboratory we recently applied the specific inhibition tech- 

 nique to a study of the Rh blood group receptors. Hackel, Smolker, and 

 Fenske (1958) reported that anti-Rh sera are inhibited specifically 

 by a number of ribonucleic acid derivatives, which suggested that the 

 Rh antigens are at least partly ribonucleotide in nature. We found 

 that human anti-D serum is also inhibited, weakly it is true, but 

 apparently specifically, by the "unnatural" sugars of Makela's group 

 4, including L-mannose, L-glucose, and D-gulose (Table 7-6). It is 

 not inhibited by the "natural" enantiomers of these sugars or by 

 any other sugars we have tried. 



