Supported by the DRK-Blutspendedienst Baden-Württemberg-Hessen, Mannheim; by the University of Ulm (Forschungsförderungsprojekt P. 531); and by the Deutsche Gesellschaft für Transfusionsmedizin und Immunhämatologie (Project DGTI/fle/00-01).
The RHCE allele ceRT: D epitope 6 expression does not require D-specific amino acids
Article first published online: 15 AUG 2003
Volume 43, Issue 9, pages 1248–1254, September 2003
How to Cite
Wagner, F. F., Ladewig, B. and Flegel, W. A. (2003), The RHCE allele ceRT: D epitope 6 expression does not require D-specific amino acids. Transfusion, 43: 1248–1254. doi: 10.1046/j.1537-2995.2003.00495.x
- Issue published online: 15 AUG 2003
- Article first published online: 15 AUG 2003
- Received for publication March 10, 2003; revision received April 28, 2003, and accepted April 28, 2003.
BACKGROUND: False-positive D typing in patients may lead to anti-D immunization caused by D+ transfusions or by omission of anti-D prophylaxis. Known causes of such errors are RhCE variants carrying RhD-specific amino acids and cold agglutinin activity of some frequently used monoclonal anti-D.
STUDY DESIGN AND METHODS: The molecular basis of eight samples referred because of “false-positive” reactions with some commercial monoclonal anti-D was investigated by PCR and nucleotide sequencing from genomic DNA. PCR with sequence-specific priming was developed to specifically detect the underlying aberrant RHCE allele. The D epitope profile of the allele was determined by serology.
RESULTS: The aberrant reactivity of the samples was caused by the RHCE allele RHCE(R154T) that occurred in a cde haplotype. The phenotype dubbed ceRT expressed the important D epitope 6, which is the target epitope of most monoclonal anti-D used in routine typing.
DISCUSSION: The characterization of ceRT demonstrated a previously unknown mechanism of antigen D expression that does not require any D-specific amino acid. At least for some D epitopes, D-like structures may be mimicked by RhCE proteins carrying amino acid substitutions not representative for RhD.