哈尔滨市41例HIV-1感染者Vpu基因特征分析

Genotyping analysis of HIV-1 strains isolated from newly-identified patients prior to antiviral treatment in Harbin of China

目的了解哈尔滨市未经抗病毒治疗HIV-1感染者人群中部分感染者HIV-1 Vpu基因亚型和变异特征。方法采集哈尔滨市50例未经抗逆转录病毒治疗的HIV-1感染者的抗凝全血,分离外周血单核细胞(PBMC)提取前病毒基因组DNA,用巢氏聚合酶链反应(Nested-PCR)对HIV-1 Vpu基因进行扩增,并使用产物直接测序。应用Sequencher 4.9进行序列清理,Bioedit和MEGA5.05软件进行序列比对及系统发生分析。结果 50例HIV-1感染者的抗凝全血样本中最终有41例(82.0%)成功扩增并完成测序分型。系统进化树显示该41例中34例感染者体内HIV的Vpu基因区与云南瑞丽株RL42(泰国B亚型)聚集在一起,属于B′亚型,7例属于欧美B亚型。各病毒株Vpu区组内离散率为(9.5±1.1)%,与国际标准毒株(HXB2)线性分析可发现某些区域的氨基酸变异,变异主要集中在10～47、70～104、115～147、174～205四个区域。结论哈尔滨市未经抗病毒治疗HIV-1感染者人群中存在属B′亚型和欧美B亚型病毒流行株,其中属B′亚型的流行株最有可能起源于云南吸毒人群流行株。Vpu在组内有一定的保守性,其结构性区域和基序可能为日后抑制HIV-1病毒的复制和释放提供理论指导。

Objective To study the genetic variations of HIV-1 strains isolated from newly-identified patients prior to antiviral treatment in Harbin of China. Methods Peripheral blood samples were collected from 50 HIV-1 infected individuals who had never received any anti-retroviral therapy. Proviral DNA was extracted from peripheral blood mononuclear cells and HIV 1 Vpu gene was amplified by using nested-PCR and verified by sequencing. Sequencer 4.9 software was applied to clean up the sequences, and BioEdit MEGAS. 05 were used to analyze the Vpu sequences. Results HIV-1 Vpu gene sequence was successfully obtained from 41 out of the 50 samples. Phylogenetic analysis confirmed 34 strains as HIV-1 subtype B＇ viruses which were closely related to the RL42 strain previously isolated from Yunnan province of China, 7 strains were categorized as B strains reported in Europe and United States of America. The genetic distance among the isolates was （9.5 ± 1.1） %. Some amino acid changes were found when comparing with standard sequence with the mutations mostly occurred at amino acid positions 10-47, 70-104, 115-147 and 174-205. Conclusions Subtypes Br and B of HIV-1 virus strains were found from newly-identified patients prior to any anti-viral therapy in Harbin of China. The B＇ subtype may originate from drug users in Yunnan province of China. The HIV-1 Vpu gene of these patients is relatively conserved with only a few variations.