INVESTIGADORES
COTORRUELO Carlos Miguel
congresos y reuniones científicas
Título:
Association of C and E expression with RHD alleles with the potential of anti-D immunization
Autor/es:
LUJÁN M; TRUCCO BOGGIONE C; GARCÍA BORRÁS S; BIONDI C; RACCA A; COTORRUELO C
Lugar:
Buenos Aires
Reunión:
Congreso; 1st French-Argentine Immunology Congress. LVIII Reunión Annual de la Sociedad Argentina de Inmunología; 2010
Institución organizadora:
Sociedad Argentina de Inmunología
Resumen:
The Rh system is highly polymorphic and one of the most clinically significant blood group in transfusion medicine. Reliable routine D typing approaches should be performed to identify some D variants that can cause anti-D alloimmunization upon transfusion. However, extremely weak D expression, termed DEL, may be confound from truly D negative units and used for D negative recipients. The aim of this study was to investigate the presence of RHD alleles in serologically D negative individuals. Blood samples from 661 D negative blood donors were studied. The Rh phenotype was performed by hemmaglutination. The presence of the D antigen was further analyzed by the indirect antiglobulin test. DNA samples were initially screened using a multiplex PCR strategy that amplifies intron 4 and the 3 unstranslated region of the RHD gene. Samples carrying RHD specific fragments were further studied by RHD exon scanning. Uncharacterized samples were analyzed by microarray strategies and sequencing. In the 661 D negative samples studied, 69 (8.93 %) were C positive or E positive. Molecular studies showed that 8 samples carried RHD specific fragments. In 3 C positive samples we detected RHD-RHCE hybrid alleles: one RHD-CE(3-7)-D and 2 RHD-CE(3-9)-D. One C positive sample carried the RHD(361del11) allele. All these alleles were reported to be associated with a D negative phenotype. We also found one C positive sample with the characteristic polymorphism of a DEL(M295I) phenotype and 3 E positive samples carrying an allele that had never been described, named RHD(46T>C). These new variants were serologically retested by adsorption elution assays and proved to be DEL phenotypes. These findings suggest that clinically important variants in D negative individuals are associated with C or E antigens. The detection of DEL alleles in donors is essential to minimize the risk of anti-D alloimmunization.