Carmo Julia Cavalcante do, Klippel Prissyla de Souza, Cordeiro Sabrine da Costa, Fernandes Ângela Maria Dos Santos, Pinto Raquel Medeiros, Weber Simone Schneider, Fantin Cleiton
Universidade do Estado do Amazonas (UEA), Manaus, AM, Brazil.
Fundação de Hematologia e Hemoterapia do Amazonas (Hemoam), Manaus, AM, Brazil.
Rev Bras Hematol Hemoter. 2017 Apr-Jun;39(2):122-126. doi: 10.1016/j.bjhh.2017.01.003. Epub 2017 Feb 22.
Immune thrombocytopenia is an immune disease characterized by thrombocytopenia and bleeding due to platelet antibodies against platelet membrane glycoproteins. Human platelet antigens are derived from polymorphisms of these glycoproteins. The aim of this study was to investigate human platelet antigen frequencies in immune thrombocytopenia patients from the state of Amazonas, Brazil and investigate the potential association between specific antigens and risk for immune thrombocytopenia.
Human platelet antigen typing was performed by BeadChip technology to determine allelic variants of 11 systems (HPA-1 to HPA-9, HPA-11 and HPA-15). Thirty-six patients (8 male and 28 female) with a median age of 34 years (range: 9-69 years) were evaluated and compared with data from Amazonas blood donors.
Platelet counts varied from 3 to 98×10/L. The allele frequencies were 0.944 for HPA-1a, 0.056 for HPA-1b, 0.847 for HPA-2a, 0.153 for HPA-2b, 0.555 for HPA-3a, 0.444 for HPA-3b, 0.805 for HPA-5a, 0.222 for HPA-5b, 0.9975 for HPA-9a, 0.025 for HPA-9b, 0.486 for HPA-15a and 0.513 for HPA-15b. Among immune thrombocytopenia individuals, no b allele of the HPA-4, -6, -7, -8 and -11 were found.
The results suggest HPA-1a, HPA-3b and HPA-5b are immune thrombocytopenia-specific autoepitopes.
免疫性血小板减少症是一种免疫性疾病，其特征为血小板减少以及因针对血小板膜糖蛋白的血小板抗体而导致的出血。人类血小板抗原源自这些糖蛋白的多态性。本研究的目的是调查巴西亚马孙州免疫性血小板减少症患者的人类血小板抗原频率，并研究特定抗原与免疫性血小板减少症风险之间的潜在关联。
采用BeadChip技术进行人类血小板抗原分型，以确定11个系统（HPA-1至HPA-9、HPA-11和HPA-15）的等位基因变体。对36例患者（8例男性和28例女性）进行了评估，这些患者的中位年龄为34岁（范围：9至69岁），并与亚马孙州献血者的数据进行了比较。
血小板计数在3至98×10⁹/L之间。HPA-1a的等位基因频率为0.944，HPA-1b为0.056，HPA-2a为0.847，HPA-2b为0.153，HPA-3a为0.555，HPA-3b为0.444，HPA-5a为0.805，HPA-5b为0.222，HPA-9a为0.9975，HPA-9b为0.025，HPA-15a为0.486，HPA-15b为0.513。在免疫性血小板减少症个体中，未发现HPA-4、-6、-7、-8和-11的b等位基因。
结果表明HPA-1a、HPA-3b和HPA-5b是免疫性血小板减少症特异性自身表位。
