Kløve-Mogensen Kirstine, Haunstrup Thure Mors, Bilde Anne-Louise Fjordside, Steffensen Rudi
Department of Clinical Immunology, Aalborg University Hospital, Aalborg, Denmark.
Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.
Vox Sang. 2025 Jun;120(6):605-614. doi: 10.1111/vox.70020. Epub 2025 Mar 25.
Human neutrophil antigen 2 (HNA-2), encoded by the CD177 gene, is considered one of the most important neutrophil antigens in human medicine, but molecular testing of CD177 is complicated and therefore not a standard procedure for investigating CD177 expression. CD177 expression can vary from 0% to 100%, and to date, the molecular basis for altered or non-expressed genes has not been determined. Reliance on phenotyping and crossmatching to investigate these neutropenic clinical cases is inconvenient for patients and demands substantial resources within the laboratory. The purpose of this study was therefore to test a new molecular testing approach based on long-read nanopore sequencing.
DNA from 44 Danish blood donors with different levels of CD177 expression, 22 of whom were found to be CD177 null, was selected as test samples. All the DNA was sequenced for the first eight exons and the beginning of exon 9 of CD177.
All incidences of CD177 null cases could be associated with the known variant c.787A>T;p.K263X (rs20182172), and a correlation was observed between c.787A>T heterozygosity and a reduced expression of CD177, which is consistent with previously published findings. The c.1291G>A;p.G431R (rs78718189) variant was found to be linked to the atypical expression of CD177. The nanopore assay revealed a total of 14 variants in 7 exons in the 44 tested samples.
On the basis of these observations, we conclude that long-read nanopore sequencing can be a reliable tool for the routine laboratory molecular testing of CD177.
由CD177基因编码的人类中性粒细胞抗原2（HNA-2）被认为是人类医学中最重要的中性粒细胞抗原之一，但CD177的分子检测较为复杂，因此并非研究CD177表达的标准程序。CD177的表达可在0%至100%之间变化，迄今为止，基因改变或不表达的分子基础尚未确定。依靠表型分析和交叉配型来研究这些中性粒细胞减少的临床病例，对患者来说不方便，且需要实验室投入大量资源。因此，本研究的目的是测试一种基于长读长纳米孔测序的新分子检测方法。
选择44名丹麦献血者的DNA作为测试样本，这些献血者的CD177表达水平不同，其中22人被发现为CD177缺失型。对所有DNA的CD177前八个外显子和第九外显子起始部分进行测序。
所有CD177缺失病例均与已知变体c.787A>T;p.K263X（rs20182172）相关，并且观察到c.787A>T杂合性与CD177表达降低之间存在相关性，这与先前发表的研究结果一致。发现c.1291G>A;p.G431R（rs78718189）变体与CD177的非典型表达有关。纳米孔检测在44个测试样本的7个外显子中总共发现了14个变体。
基于这些观察结果，我们得出结论，长读长纳米孔测序可以成为CD177常规实验室分子检测的可靠工具。
