Premium
The platelet‐specific alloantigen Pl A1 (HPA‐1a): a comparison of flow cytometric immunophenotyping and genotyping using polymerase chain reaction and restriction fragment length polymorphism in a Swedish blood donor population
Author(s) -
Forsberg B.,
Jacobsson S.,
Stockelberg D.,
Kutti J.,
Rydberg L.,
Wadenvik H.
Publication year - 1995
Publication title -
transfusion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.045
H-Index - 132
eISSN - 1537-2995
pISSN - 0041-1132
DOI - 10.1046/j.1537-2995.1995.35395184281.x
Subject(s) - genotype , genotyping , neonatal alloimmune thrombocytopenia , flow cytometry , microbiology and biotechnology , restriction fragment length polymorphism , polymerase chain reaction , biology , typing , population , immunophenotyping , immunology , genetics , medicine , gene , pregnancy , fetus , environmental health
BACKGROUND: There is an increasing interest in the development of rapid and reliable techniques for platelet alloantigen typing. STUDY DESIGN AND METHODS: By use of standardized flow cytometry and a specific human alloantiserum, 236 Swedish blood donors were immunophenotyped for the platelet‐specific alloantigen, PlA1 (HPA‐1a). RESULTS: Ten individuals (4.2%) had low fluorescence intensities and were considered PlA1‐ negative (HPA‐1a‐negative); all of them also demonstrated a PlA2/PlA2 (HPA‐1b/1b) genotype in a polymerase chain reaction and restriction fragment length polymorphism (PCR‐RFLP) assay of the underlying DNA polymorphism. The remaining population had clear positive fluorescence and was regarded as PlA1‐positive (HPA‐1a‐positive). The fluorescence distribution histogram among PlA1‐positive (HPA‐1a‐positive) individuals was dome‐shaped, and those individuals who were homozygous for PlA1 (HPA‐1a) could not be distinguished from those who were heterozygous. This finding was further substantiated by PCR‐RFLP analysis of the PlA1/PlA2 (HPA‐1a/1b) genotype; a heterozygous genotype was found among those having a medium fluorescence intensity as well as among those having a strong fluorescence intensity. CONCLUSION: Flow cytometry is a valuable tool for large‐scale detection of PlA1 (HPA‐ 1a). However, flow cytometry based on only one antiserum cannot distinguish between homozygous and heterozygous carriers of PlA1 (HPA‐ 1a). For zygosity testing and when platelets are difficult to obtain, the PCR‐RFLP technique is the assay of choice.