Schematic representation of the antigen D on the erythrocyte´s surface. The normal RhD protein is shown (left). Every sphere represents an amino acid. Six extracellular loops of amino acids are shown (light yellow and light grey). Transmembranous protein segments are depicted in reddish. The RhD protein differs from the RhCE protein (not shown) be seven extracellular amino acids only (yellow). All other extracellular amino acids (light yellow and light blue) Schematic representation of the antigen D on the red blood cell´s surface are identical between the RhD- and RhCE-protein. In the DVI-protein (right), two loops carry the RhCE-specific sequence (light blue) rather than the RhD-specific sequence. Thus, the extracellular parts of the DVI-protein differ from the normal RhD-protein by three amino acids only (blue). Other transmembranous and intracellular differences may, however, also effect the protein configuration and are not shown for simplicity. 

3D Model of the Rhesus Antigen on the Red Blood Cell Surface

A transfusion recipient with the DVI phenotype may produce an anti-D-antibody (blue arrow) directed against parts of the normal RhD-protein (yellow) that his or her DVI-protein does not carry, because they are substituted by RhCE-specific parts (light blue and blue). Monoclonal IgM anti-D-antibodies that are used for RhD-typing of patients are directed against these parts fo the RhD-protein. Because the DVI-protein does not carry these protein parts, the monoclonal IgM anti-D cannot bind the DVI-protein and react serologically negative.

last modified 21 Febr 1998
 Text in Deutsch