Implementation of a Flow-Cytometric Assay for Rapid Detection of HPA-1-Compatible Platelet Donors under Routine Conditions

Abstract

Background: Antibodies against the HPA-1a platelet antigen are a frequent cause of alloimmune thrombocytopenia. For diagnosis and transfusion requirements, blood banks should provide a number of HPA-1-typed platelet donors. Material and Methods: We evaluated a serological, flow-cytometric HPA-1 typing assay allowing for the differentiation of the HPA-1a and -1b variant of the platelet glycoprotein GPIIIa (ADIAflo^® Platelet HPA-1). Results: Of 172 donors tested, 6 HPA-1b-homozygous individuals were identified. These results were confirmed by SSP-PCR genotyping. 120 donors were tested HPA-1ahomozygous. The test also distinguishes HPA-1a-homozygous from HPA-1a/1b-heterozygous platelets (n=46). Donors with a result near the cut-off value between HPA-1a-homozygous and HPA-1a/1b-heterozygous were retyped by SSP-PCR. In this group, we observed one case of mistyping by the serological procedure. Conclusion: The ADIAflo Platelet HPA-1 typing assay has been successfully implemented in our daily routine for rapid detection of HPA-1-compatible platelet donors. Results near the cut-off value distinguishing HPA-1ahomozygous from HPA-1a/1b-heterozygous samples should be confirmed by genotyping.