造血干细胞移植受-供者HLA抗原识别部位的核苷酸匹配研究

Study on HLA nucleotide sequence matching in epitope positions among recipient-donor pairs for allogenic hematopoietic stem-cell transplantation

目的研究中国人群等待造血干细胞移植受一供者人类白细胞抗原（human leukocyte antigens，HLA）-A、-B、-Cw、-DRB1、-DQB15个位点的等位基因及核苷酸匹配情况，从单核苷酸水平探讨最佳供选择方案。方法采用聚合酶链反应测序分型法（polymerase chain reaction-sequence-based typing，PCR-SBT），对537对中国人群等待造血干细胞移植受-供者HLA-A、-B、-Cw、-DRB1、-DQB1位点的等位基因进行序列分型，应用BLAST工具分析受-供者HLA核苷酸差异。结果537对受-供者中HLA—A、-B、-Cw、-DRB1、-DQB1五位点核苷酸完全匹配占16．20％，单个等位基因错配的受-供者对分别占8．38％，0．74％，12．29％，2．42％和2．79％，两个或两个以上等位基因错配比率占42.65％。检出A＊02：01-A＊02：06，A＊02：06-A＊02：07，Cw＊03：04-Cw＊15：02，Cw＊03：03-Cw＊04：01，Cw＊03：04-Cw＊14：02，Cw＊03：03-Cw＊08：01，DRB1＊04：03：01-DRB1＊04：05不容许错配等位基因对。两对受-供者B＊07：05：01-B＊07：06，Cw＊07：01：01-Cw＊07：06抗原识别区外核苷酸错配。结论在造血干细胞移植选择HLA错配的无关供者时注意受-供核苷酸匹配差异，对HLA抗原识别区内的核苷酸匹配差异和抗原识别区外的核苷酸匹配差异应当加以区别。本研究结果为优化供者选择顺序提供科学参考数据。

Objective To analyze the human leukocyte antigens （HLA）-A, -B, -Cw, -DRBI and DQB1 nucleotide sequences between patients waiting for allogenic hematopoietic stem-cell transplantation （HSCT） and donors in Chinese population, and to establish strategy for maximizing optimal donor selection. Methods HLA high-resolution typing in a total of 537 recipient-donor pairs was determined by sequence based typing （SBT） method. The nucleotide BLAST tool was used to compare the nucleotide sequences among recipient-donor pairs. Results Only 16.20% （88/537） of recipient-donor pairs were found to fully match for nucleotide sequences of all HLA-A, -B, -Cw, -DRB1 and -DQB1 loci. Mismatch rate in single locus were 8. 38% in HLA-A,0.74% in HLA-B, 12.29% in HLA-C,2.42% in HLA-DRB1, and 2.79% in HLA-DQB1, respectively. Mismatch rate in two or multiple HLA loci was 42. 65%. Nonpermissive allele mismatch combinations （A ＊ 02 ： 01-A ＊ 02 ： 06, A ＊ 02 ： 06- A ＊ 02 ： 07, Cw ＊ 03 ： 04-Cw 15：02,Cw＊ 03：03-Cw ＊ 04：01, Cw ＊03：04-Cw ＊ 14：02, Cw ＊ 03：03-Cw ＊ 08：01, DRB1 ＊ 04：03：01- DRB1 ＊ 04：05） were detected in single mismatch HLA locus of recipient-donor pairs, mismatches of B ＊ 07.. 05：01-B ＊ 07：06, Cw ＊ 07：01：01-Cw ＊ 07：06 combinations outside of epitope positions were detected in two recipient-donor pairs. Conclusion Our data suggested that attention should be paid in comparing nucleotide sequences between recipient and donor, and in distinguishing nucleotide sequence mismatches within and outside of the epitope positions. These results could serve as guidelines for donor selection.