Section of Transfusion Medicine and Cellular Therapy, Department of Hemotherapy, Hospital Albert Einstein, São Paulo, Brazil; Platelet Immunology Unit, Institut National de Transfusion Sanguine (INTS), Paris, France.
Transfusion. 2014 Feb;54(2):405-11. doi: 10.1111/trf.12272. Epub 2013 Jun 13.
Human platelet antigens (HPA) polymorphisms may cause HPA alloimmunization, platelet (PLT) refractoriness, fetomaternal alloimmune thrombocytopenia, and posttransfusion purpura. Characterized by significant racial admixture, the Brazilian population might benefit from the knowledge about HPA frequency to guide decision-making concerning PLT transfusion.
HPA frequencies were determined in 158 DNA samples from Brazilian blood donors by microarray for HPA-1 to -9, -11, and -15. A HPA-2 discrepancy was solved by polymerase chain reaction with sequence-specific primers (PCR-SSP) and sequencing.
While a alleles were predominant for HPA-1 to -9 and -11, b alleles were absent for HPA-6, -7, -8, and -11. HPA-3 and HPA-15 had a higher prevalence of ab genotypes. One case of HPA-4ab and two cases of HPA-9abw were detected, the latter not previously described in Brazilian blood donors. One sample was not interpretable for HPA-2 due to a GPIb 468 C>G mutation; this donor was characterized as HPA-2ab by PCR-SSP and sequencing.
Allele frequencies were comparable to those described in other Brazilian studies. Rare HPA-9 alleles were described in Brazilians for the first time. A mutation near the HPA-2 polymorphism suggests that complementary methods might be necessary in specific cases. PLT genotyping by microarray proved to be fast, accurate, and reliable.
人类血小板抗原（HPA）多态性可能导致 HPA 同种免疫、血小板（PLT）反应性降低、胎儿-母体同种免疫性血小板减少症和输血后紫癜。巴西人口具有明显的种族混合特征，因此了解 HPA 频率可能有助于指导 PLT 输血决策。
通过微阵列对来自巴西献血者的 158 个 DNA 样本进行 HPA-1 至-9、-11 和-15 的 HPA 频率测定。通过聚合酶链反应与序列特异性引物（PCR-SSP）和测序解决了 HPA-2 差异。
虽然 a 等位基因在 HPA-1 至-9 和-11 中占优势，但 b 等位基因在 HPA-6、-7、-8 和-11 中不存在。HPA-3 和 HPA-15 的 ab 基因型更为常见。检测到 1 例 HPA-4ab 和 2 例 HPA-9abw，后者在巴西献血者中尚未描述。由于 GPIb 468 C>G 突变，1 个样本无法解释 HPA-2，该供体通过 PCR-SSP 和测序被鉴定为 HPA-2ab。
等位基因频率与其他巴西研究中描述的相似。首次在巴西人中描述了罕见的 HPA-9 等位基因。HPA-2 多态性附近的突变提示在特定情况下可能需要互补方法。微阵列 PLT 基因分型快速、准确、可靠。
