Mandal D, Jana S, Panda S, Bhattacharya S, Ghosh T C, Bhattacharya S K, Chakrabarti S
National Institute of Cholera & Enteric Diseases (ICMR), Calcutta.
Indian J Med Res. 2000 Nov;112:165-72.
BACKGROUND & OBJECTIVES: Different routes for the transmission of HIV-1 in India have been reported and the majority of infections occurred through heterosexual route of transmission. In order to understand the dynamics of HIV-1 transmission, a systematic study was undertaken to determine the viral subtypes circulating among the female sex workers in Calcutta, India.
Peptide enzyme immunoassay (PEIA), heteroduplex mobility assay (HMA) and DNA sequence analysis were used to ascertain the HIV-1 subtypes.
V3 serotyping of 52 HIV-1 seropositive samples identified 33 (60%) to be subtype C. A DNA fragment within C2-V3/C2-V5 regions of HIV-1 gp120 was amplified directly from the lymphocyte DNA to avoid any bias in selecting viral variants and used in HMA. Of the 40 samples analyzed, 38 (95%) belonged to subtype C and 2 were found to be non-typable. Further analysis of these 38 samples revealed that 26 (68%) had maximum homology to the C3-Indian reference strain (IND868), 11 (29%) were most homologous to C2-Zambian strain (ZM18) and 1 (3%) showed close resemblance to C1-Malawi strain (MA959). Nucleotide sequence of 11 subsamples encompassing about 325 base pairs was aligned for the Indian and other geographically distinct isolates. On distance and parsimony trees, most of the samples (8/11) clustered together as subtype C.
INTERPRETATION & CONCLUSIONS: Subtype C was the major circulating HIV-1 strain in this geographical region, although variation within this subtype was also noticed. DNA sequence analysis was found to be the best method in determining the nature of the HIV-1 subtype followed by HMA and peptide enzyme immunoassay. These findings may have important implications for the design of effective vaccines in India and emphasizes the need for constant monitoring of the HIV-1 subtypes in different parts of India.
印度已报道了HIV-1的不同传播途径,且大多数感染是通过异性传播途径发生的。为了解HIV-1传播的动态情况,开展了一项系统性研究,以确定印度加尔各答女性性工作者中流行的病毒亚型。
采用肽酶免疫测定法(PEIA)、异源双链迁移率测定法(HMA)和DNA序列分析来确定HIV-1亚型。
对52份HIV-1血清阳性样本进行V3血清分型,确定其中33份(60%)为C亚型。直接从淋巴细胞DNA中扩增HIV-1 gp120的C2-V3/C2-V5区域内的一个DNA片段,以避免在选择病毒变体时产生任何偏差,并将其用于HMA。在分析的40份样本中,38份(95%)属于C亚型,2份无法分型。对这38份样本的进一步分析显示,26份(68%)与C3-印度参考毒株(IND868)具有最大同源性,11份(29%)与C2-赞比亚毒株(ZM18)最同源,1份(3%)与C1-马拉维毒株(MA959)相似。对包含约325个碱基对的11个亚样本的核苷酸序列进行比对,以分析印度和其他地理上不同的分离株。在距离树和简约树上,大多数样本(8/11)聚为C亚型。
C亚型是该地理区域主要流行的HIV-1毒株,不过也注意到该亚型内存在变异。发现DNA序列分析是确定HIV-1亚型性质的最佳方法,其次是HMA和肽酶免疫测定法。这些发现可能对印度有效疫苗的设计具有重要意义,并强调有必要持续监测印度不同地区的HIV-1亚型。