中国大陆地区发现一例罕见的血小板抗原HPA-10bw等位基因报告

Case report of a rare platelet-specific antigen HPA-10bw allele found in Chinese mainland

采用序列特异性引物-聚合酶链式反应(PCR-SSP)为基础的人类血小板抗原(HPA)基因分型技术做群体调查,在1,000例受检者中发现1例罕见的HPA-10w(a+b+)杂合子个体,为了验证分型的可靠性,使用PCR反应特异性扩增HPA-10基因片段,然后测序分析。结果表明,nt263位G→A导致GPⅢa糖蛋白第62位精氨酸(CGA)→谷氨酰胺(CAA),产生HPA-10bw抗原特异性。在中国人群中检测出HPA-10bw低频抗原,提示在血小板同种免疫引起的新生儿同种免疫血小板减少症(NAIT)、输血后紫癜症(PTP)以及血小板输注无效症(PTR)的诊断中,该抗原具有临床意义。

A total of 1,000 Chinese blood donors were typed for human platelet antigens （HPA） using a sequence specific primers -polymerase chain reaction （PCR-SSP） based HPA genotyping method. An individual with a rare HPA-10w（a＋b＋） genotype was found. In order to confirm the typing results, a fragment of HPA-10 gene was amplified by PCR and then sequenced. Sequencing data showed that a single G to A substitution at nucleotide 263 occurred, resulting in amino acid change from Arg（CGA） to GIn（CAA） at position 62 of GPⅢa protein. The substitution generated antigenic specificity HPA-10bw. The detection of an HPA-10bw allele in the Chinese population suggests that this rare allele should be considered in platelet alloimmunization, such as neonatal alloimmune thrombocytopenia （NAIT）, post-transfusion thrombocytopenic purpura （PTP） and post-transfusion refractoriness to platelets （PTR）.