Auewarakul P, Louisirirotchanakul S, Sutthent R, Taechowisan T, Kanoksinsombat C, Wasi C
WHO Collaborating Centre on AIDS, Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Viral Immunol. 1996;9(3):175-85. doi: 10.1089/vim.1996.9.175.
Twenty-seven HIV-1 isolates were obtained from 51 asymptomatic HIV-1-infected pregnant women or intravenous drug users (IDUs) in Bangkok. Using heteroduplex mobility assay (HMA), it was found that the majority of the HIV-1 isolates (9 out of 11) from pregnant women belonged to genetic subtype E, whereas most of the subtype B HIV-1 isolates (15 out of 16) were isolated from IDUs. The HIV-1 isolates were tested for their susceptibility to neutralization or antibody-dependent enhancement with homologous and heterologous plasma of the two different genetic subtypes, B and E. Overall, HIV-1 neutralizing activity could be found in 37.3% of virus/plasma pairs for both subtypes B and E. No significant correlation could be identified between the two genetic subtypes (B and E) and their susceptibility to neutralization. Subtype B plasma demonstrated frequent cross-neutralization of subtype E viruses in 38.5% of virus/plasma pairs, whereas cross-neutralization activity of subtype E specific plasma samples was more limited and could cross-neutralize subtype B viruses only in 15.8% of cases. Some of the viral strains independently of their genetic subtypes were more susceptible to neutralization by plasma specific for both subtype E or subtype B, suggesting that this phenomenon is related to the proper biological properties of a viral strain. Antibody-dependent enhancement of HIV-1 strains could be detected in 12/83 (14.5%) virus-plasma pairs irrespective of genetic subtypes. Similar to neutralization results, the HIV-1 enhancing activity of plasma was mostly isolate-specific. The HIV isolates that were susceptible to neutralization were not enhanced by any plasma. On the other hand, the HIV isolates that were enhanced by plasma were resistant to neutralization in most cases. Such a dissociation between susceptibility to neutralization or enhancement may be indicative of the existence of discrete epitopes determining the two distinct viral properties.
从曼谷51名无症状的HIV-1感染孕妇或静脉吸毒者（IDU）中获取了27株HIV-1分离株。使用异源双链迁移率分析（HMA）发现，孕妇的大多数HIV-1分离株（11株中的9株）属于基因E亚型，而大多数B亚型HIV-1分离株（16株中的15株）是从静脉吸毒者中分离出来的。用两种不同基因亚型B和E的同源和异源血浆检测了HIV-1分离株对中和或抗体依赖性增强的敏感性。总体而言，B和E两种亚型的病毒/血浆对中，37.3%可检测到HIV-1中和活性。两种基因亚型（B和E）与其对中和的敏感性之间未发现显著相关性。B亚型血浆在38.5%的病毒/血浆对中表现出对E亚型病毒的频繁交叉中和作用，而E亚型特异性血浆样本的交叉中和活性更有限，仅在15.8%的病例中能交叉中和B亚型病毒。一些病毒株，无论其基因亚型如何，对E亚型或B亚型特异性血浆的中和作用更敏感，这表明这种现象与病毒株的固有生物学特性有关。在12/83（14.5%）的病毒-血浆对中可检测到HIV-1毒株的抗体依赖性增强，与基因亚型无关。与中和结果相似，血浆的HIV-1增强活性大多具有分离株特异性。对中和敏感的HIV分离株不会被任何血浆增强。另一方面，被血浆增强的HIV分离株在大多数情况下对中和具有抗性。这种对中和或增强敏感性之间的分离可能表明存在决定两种不同病毒特性的离散表位。
