The Sdx antigen and antibody: biochemical studies on the inhibitory property of human urine.
Anti-Sdx is an IgM complement-binding autoantibody that defines a red cell antigen which is independent of I, i, Sp1 (Pr) and Gd. Hemagglutination by the antibody is unusually sensitive to variation in pH, salt, or other charged molecular species. The antibody is inhibited by urine from Sd(a+) persons, but inhibition is a nonspecific effect caused by charged molecules. No specific Sdx substance could be demonstrated, and Sdx antigen does not appear to be directly associated with the Sid blood group. In view of these findings we propose that this antibody should be renamed anti-Rx.
D000818:Animals; D001323:Autoantibodies / Q000652:urine*; D001789:Blood Group Antigens / Q000276:immunology*; D003864:Depression, Chemical; D006168:Guinea Pigs; D006385:Hemagglutination Inhibition Tests; D006386:Hemagglutination Tests; D006801:Humans; D008297:Male; D008970:Molecular Weight; D009088:Mucoproteins / Q000494:pharmacology; D009439:Neuraminidase / Q000494:pharmacology; D011946:Receptors, Antigen / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology; D014556:Urine / Q000032:analysis; D058949:Uromodulin
D001323:Autoantibodies; D001789:Blood Group Antigens; D009088:Mucoproteins; D011946:Receptors, Antigen; C548612:UMOD protein, human; D058949:Uromodulin; D012965:Sodium Chloride; D009439:Neuraminidase