Molecular and serologic characterization of DWI, a novel “high‐grade” partial D

Abstract

The findings of this investigation emphasize the possible clinical significance of "high-grade" partial D variants that are likely to be missed by routine serology.

RHD variants in Flanders, Belgium

“…The D antigen density of variant D and control RBCs was determined by flow cytometry exactly as described, using the following five primary anti‐D: P3x35, P3x290, P3x241, P3x249, ESD1, and Brad‐3.…”

“…All D+ phenotypes including even the weakest D variants may induce anti‐D in D− subjects . In addition, individuals with partial D antigens may also develop alloanti‐D upon exposure to the entire set of D epitopes of normal D+ red blood cells (RBCs); this holds true even with only minimal epitope loss …”

Anti‐D immunization by DEL red blood cells

“…After incubation with secondary antibody (30 min at 20°C) and washing, 20,000 events per sample were acquired. Absolute D antigen densities (D antigens per RBC) were assessed by use of a standard R 1 r RBC sample (according to genotyping and family tree DCe/dce ) with 9748 D antigens per cell 16 deduced from the standard of the Fourth International Workshop on Monoclonal Antibodies against Human Red Blood Cells. For D antigen density calculation, the recommended algorithm was applied 15 .…”

Flow cytometry in transfusion medicine: an overview

“…In a study by Wagner et al [19], they very nicely present the examination of D weak alleles where flow cytometry was part of the investigation, and in total more than 50 anti-D reagents were used. Others have also characterized new RHD alleles and correlated genotype with phenotype [20,21]. Silvy et al [22] used epitope mapping of different D variants by flow cytometry with workshop-verified reagents.…”