Immunochemical Characterization of Rhesus Proteins With Antibodies Raised Against Synthetic Peptides

Rabbit polyclonal antibodies were raised against synthetic peptides corresponding to hydrophilic regions of the human Rhesus (Rh) IX cDNA-encoded polypeptide predicted to be extracellularly or intracellularly exposed in the topologic model of the Rh blood group protein. Four antibodies encompassing residues 33-45 (MPC1 ), 224-233 (MPC4), 390-404 (MPC6), and 408-41 6 (MPC8) were characterized and compared with a polyclonal anti-Rh protein obtained by immunization with purified Rh proteins. All antibodies had specificity for authentic Rh polypeptides and reacted on Western blot with Rh proteins immunoprecipitated with human monoclonal anti-RhD, -c, and -E. MPCl, but not the other antibodies, agglutinated all human erythrocytes except Rh, , and Rh, , cells, which either lack totally or are severely deficient in Rh proteins, respectively. lmmunoblotting analysis with membrane proteins from common and rare variants showed that MPCl and MPC8 reacted in Western blot with 32-Kd Rh polypeptides from all common red blood cells except those from Rhnull and Rhmod, indicating that peptide regions 33-45 and 408-