Two Examples of an Inseparable Antibody That Reacts Equally Well with D^W+ and Rh32+ Red Blood Cells

Abstract

Background and Objectives: Anti-D^W is a rare specificity that detects an antigen on D^Va red blood cells (RBCs). Some anti-D^W contain an inseparable component that cross-reacts weakly with RBCs expressing the low-incidence Rh antigen Rh32. RH32 is expressed by RBCs with either the R=^Nor the DBT phenotype. Case Report: We describe here an antibody found in the serum of 2 patients that reacts equally well with RBCs possessing either D^Va, R=^N, or DBT phenotypes. The reactivity for D^W and Rh32 antigens could not be separated by adsorption onto and elution from D^W+Rh32– or from D^W–Rh32+ RBCs. Conclusions: We suggest that amino acids encoded by nucleotides at the junction of exon 4 of RHD to exon 5 of RHCE may induce a conformation that is recognized by these equally reactive inseparable antibodies. Until such time that the epitope recognized by these antibodies is defined, we recommend use of the descriptive name anti-D^W/Rh32.