A comprehensive analysis of DEL types: partial DEL individuals are prone to anti-D alloimmunization

• Published in: Transfusion (Philadelphia, Pa.) Pa.), 2005-10, Vol.45 (10), p.1561-1567
• Main Authors: Körmöczi, Günther F., Gassner, Christoph, Shao, Chao-Peng, Uchikawa, Makoto, Legler, Tobias J.
• Format: Article
• Language: English
• Subjects: Adult; Alleles; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Antibodies, Monoclonal - immunology; Asian Continental Ancestry Group - genetics; Biological and medical sciences; Blood Group Incompatibility - etiology; Blood Group Incompatibility - immunology; Blood Group Incompatibility - prevention & control; Blood Grouping and Crossmatching - methods; Blood. Blood and plasma substitutes. Blood products. Blood cells. Blood typing. Plasmapheresis. Apheresis; Child; Diseases of mother, fetus and pregnancy; Epitope Mapping; Epitopes - biosynthesis; Epitopes - genetics; Epitopes - immunology; Erythrocyte Membrane - immunology; European Continental Ancestry Group - genetics; Female; Flow Cytometry; Gene Expression Regulation - genetics; Genotype; Gynecology. Andrology. Obstetrics; Haplotypes - genetics; Human viral diseases; Humans; Immunosorbent Techniques; Infectious diseases; Isoantibodies - biosynthesis; Isoantibodies - immunology; Male; Medical sciences; Middle Aged; Miscellaneous; Phenotype; Pregnancy. Fetus. Placenta; Rh Isoimmunization - epidemiology; Rh Isoimmunization - etiology; Rh Isoimmunization - genetics; Rh-Hr Blood-Group System - analysis; Rh-Hr Blood-Group System - biosynthesis; Rh-Hr Blood-Group System - classification; Rh-Hr Blood-Group System - genetics; Rh-Hr Blood-Group System - immunology; Rho(D) Immune Globulin; Serologic Tests; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Viral diseases
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1111/j.1537-2995.2005.00584.x

BACKGROUND: The D antigen of the polymorphic Rh blood group system is of particular clinical importance regarding transfusion‐ and pregnancy‐induced alloimmunization. Different RhD variants with specific clinical implications have been characterized. The least expressed D variants collectively called DEL are serologically detectable only by adsorption‐elution techniques, with so far only poorly defined antigenic properties. STUDY DESIGN AND METHODS: A comprehensive immunohematologic analysis of five of the six currently known DEL genotypes was performed. DEL phenotypes associated with the RHD(M295I), RHD(IVS3+1g>a), RHD(K409K), RHD(X418L), or RHD(IVS5‐38del4) allele were characterized with extended serology and flow cytometry. RESULTS: Epitope mapping with adsorption‐elution revealed a prominent D epitope loss in the RHD(IVS3+1g>a)‐associated DEL phenotype, whereas in the other four DEL types no signs of qualitative D antigen alteration were detected. The observation of alloanti‐D in two RHD(IVS3+1g>a) cases confirmed the partial nature of this DEL phenotype. The RHD(M295I) phenotype exhibited the highest D antigen expression among all investigated DEL types, as determined by a semiquantitative adsorption‐elution approach and flow cytometry. CONCLUSION: In conclusion, evidence is provided that different DEL genotypes code either for partial or complete D antigen expression and that this finding is clinically relevant.