Rayfield M A, Downing R G, Baggs J, Hu D J, Pieniazek D, Luo C C, Biryahwaho B, Otten R A, Sempala S D, Dondero T J
HIV/Retrovirus Diseases Branch, Division of AIDS, STD and TB Laboratory Research, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
AIDS. 1998 Mar 26;12(5):521-7. doi: 10.1097/00002030-199805000-00014.
Previous data, based on a small sampling of convenience, reported subtypes A, B, C, D, and G in Uganda, but neither the extent nor the proportion of these subtypes could be evaluated. To establish correctly the prevalence and distribution of HIV-1 subtypes, we analysed viral clades in 739 HIV-1-seropositive specimens from different areas of Uganda.
Blood specimens from 1100 patients were collected in five districts of Uganda. Within this collection, 929 HIV-1-seroreactive samples underwent analysis of viral DNA, and 739 were selected for further subtyping in env or pol regions.
Using a combination of subtype A- and D-specific probes to C2-V3 region and DNA sequencing, HIV-1 env subtypes were determined in 594 specimens: 341 were of subtype A (57.4%), 250 of subtype D (42.1%), and three of subtype C (0.5%). Sixty-two samples showed reactivity with both probes, suggesting potential mixed infections, cross-reactivity to probes, or possibly other subtypes. Subsequent sequence analysis of 19 randomly selected specimens revealed subtypes A (n = 4), D (n = 12), and C (n = 3). Sequence analysis of the 27 samples chosen from the remaining 83 samples, which could be amplified only with viral gp41 or protease gene primers, classified them as subtypes A (n = 13) and D (n = 14). No significant clinical, demographic, or geographic differences were found between HIV-1 infections with viruses of subtypes A and D, despite considerable genetic diversity within these clades.
This is the first major population-based study of the prevalent HIV-1 strains in an African country selected for vaccine trials. The subtyping methods we describe should be of use to investigators seeking to conduct large-scale screening for HIV variants in other populations.
以往基于小样本便利抽样的数据报告了乌干达的A、B、C、D和G亚型，但这些亚型的范围和比例均无法评估。为正确确定HIV-1亚型的流行率和分布，我们分析了来自乌干达不同地区的739份HIV-1血清阳性标本中的病毒进化枝。
在乌干达的五个地区收集了1100名患者的血液标本。在这批标本中，对929份HIV-1血清反应性样本进行了病毒DNA分析，选择其中739份在env或pol区域进行进一步的亚型分析。
使用针对C2-V3区域的A亚型和D亚型特异性探针组合以及DNA测序，在594份标本中确定了HIV-1 env亚型：341份为A亚型（57.4%），250份为D亚型（42.1%），3份为C亚型（0.5%）。62份样本与两种探针均有反应，提示可能存在混合感染、与探针的交叉反应或可能的其他亚型。随后对19份随机选择的标本进行序列分析，发现有A亚型（n = 4）、D亚型（n = 12）和C亚型（n = 3）。从其余83份仅能用病毒gp41或蛋白酶基因引物扩增的样本中选择的27份样本进行序列分析，将它们分类为A亚型（n = 13）和D亚型（n = 14）。尽管这些进化枝内存在相当大的基因多样性，但在感染A亚型和D亚型病毒的HIV-1感染者之间未发现明显的临床、人口统计学或地理差异。
这是在一个被选作疫苗试验的非洲国家中首次基于主要人群的HIV-1流行毒株研究。我们描述的亚型分析方法应有助于研究人员在其他人群中对HIV变异体进行大规模筛查。
