Molecular Basis of KELnull Phenotype in Brazilians

Author(s)

Boturao-Neto, Edmir ^[1] ; Yamamoto, Mihoko ^[1] ; Chiba, Akemi Kuroda ^[1] ; Sugano Kimura, Elisa Yuriko ^[1] ; Valgueiro Costa de Oliveira, Maria do Carmo ^[2] ; do Monte Barretto, Claudia Lumack ^[2] ; Alves Nunes, Mercia Maria ^[2] ; Lopes Albuquerque, Sergio Roberto ^[3] ; de Deus Santos, Marcos Daniel ^[4] ; Bordin, Jose Orlando ^[1]

Affiliation

^[1] Univ Fed Sao Paulo, Hematol & Transfus Med Dept, BR-04023092 Sao Paulo, SP - Brazil

^[2] Fundacao HEMOPE, Hemotherapy Dept, Recife, PE - Brazil

^[3] Fundacao Hosp Hematol & Hemoterapia Estado Amazon, Immunohematol Dept, Manaus, AM - Brazil

^[4] Univ Fed Espirito Santo, Dept Internal Med, Vila Velha, ES - Brazil

• Document type: Journal article
• Source: TRANSFUSION MEDICINE AND HEMOTHERAPY; v. 42, n. 1, p. 52-58, 2015.
• Web of Science Citations: 2

Abstract

Background: KELnull (K-0) persons can produce clinically significant anti-KEL5 antibody after transfusion and/or pregnancy, requiring K-0 blood transfusion when indicated. 37 K-0 alleles have been reported in studies over different populations, but none in Amerindian-Caucasian descendants from South America. The aim of this study was to identify the molecular basis of K-0 phenotype in Brazilians. Methods: We investigated three K-0 samples from different Brazilian blood banks (Recife, Manaus, and Vila Velha) in women with anti-KEL5. KEL antigen typing was performed by serologic techniques, and the K-0 status was confirmed by flow cytometry. PCR-RFLP and DNA sequencing of the KEL coding and exon-intron regions were also performed. Results: RBCs of the 3 patients were phenotyped as KEL:-1,-2,-3,-4,-7. The 3 patients had the same KEL{*}02/02 genotype and were negative for KEL{*}02.03 and KEL{*}02.06 alleles. The Recife K-0 patient was homozygous for IVS16 + 1g>a mutation (KEL{*}02N.31 allele). The flow cytometry with anti-KEL1, anti-KEL2, anti-KEL3, anti-KEL4, and anti-CD238 confirmed the K-0 phenotype. In addition, we found the c.1042C>T mutation (KEL{*}02N.04 allele) in both the Manaus K-0 and the Vila Velha K-0 patients. Conclusion: This report represents the first study of K-0 molecular basis performed in Amerindian-Caucasian descendants from South America. (AU)

• FAPESP's process: 05/55237-9 - Clinical and molecular aspects of antigens and antibodies of blood cells
• Grantee: Jose Orlando Bordin
• Support Opportunities: Research Projects - Thematic Grants