Serologic strategy in detecting RHD altered alleles in Brazilian blood donors

• Main Authors: Rosangela Duarte de Medeiros Person, Carine Prisco Arnoni, Janaína Guilhem Muniz, Tatiane Aparecida de Paula Vendrame, Flavia Roche Moreira Latini, Afonso José Pereira Cortez, Jordão Pellegrino, Jr, Lilian Maria de Castilho
• Format: Article
• Language: English
• Published: Elsevier 2020-10-01
• Series: Hematology, Transfusion and Cell Therapy
• Subjects: D variant; RHD alleles; Weak D; Partial D; Hemagglutination; RHD genotyping
• Online Access: http://www.sciencedirect.com/science/article/pii/S2531137919301440

Background: We evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors. Methods: We selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spin (IS) with eleven commercially available anti-D reagents in a tube and microplate. The D confirmatory tests for the presence of weak D included the indirect antiglobulin test (IAT) in a tube, gel and solid-phase red blood cell adherence (SPRCA). All DNA samples were extracted from peripheral blood and the D variants were classified using different molecular assays. Results: The RHD variants identified by molecular analysis included weak D types (1, 2, 3, 11 and 38) and partial Ds (DAR1.2, DAR1, DAR3.1, DAU0, DAU2, DAU4, DAU5, DAU6, DMH and DVII). The monoclonal-monoclonal blend RUM-1/MS26 was the best anti-D reagent used in detecting the D antigen in the IS phase in a tube, reacting with 83.2% of the D variants, while the anti-D blend D175 + 415 was the best monoclonal antibody (MoAb) used in a microplate to minimize the need for an IAT, reacting with 83.2% of the D variants. The D confirmatory tests using SPRCA showed a reactivity (3 - 4+) with 100% of the D variant samples tested. Conclusion: Our results show that, even using sensitive methods and MoAbs to ensure the accurate assignment of the D antigen, at least 17% of our donor samples need a confirmatory D test in order to avoid alloimmunization in D-negative patients.