对ddI的耐药性和对AZT的敏感性是由HIV-1逆转录酶突变引起的
M H St Clair1, J L Martin, G Tudor-Williams
1Division of Virology, Burroughs Wellcome Co., Research Triangle Park, NC 27709.
概括
将HIV-1治疗从齐多夫丁 (AZT) 转换为迪达诺辛 (ddI) 导致ddI敏感性降低,而AZT敏感性增加. 一个特定的突变出现了,赋予了对ddI的耐药性,并抑制了对AZT的耐药性,突出显示了组合疗法的重要性.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- 人类免疫缺陷病毒1型 (HIV-1) 治疗通常涉及连续的抗逆转录病毒疗法.
- 齐杜丁 (AZT) 是主要的治疗方法,但耐药性是一个重大的临床挑战.
- 切换到替代核酸逆转录酶抑制剂,如迪达诺辛 (ddI) 是一个常见的策略.
研究的目的:
- 在从AZT转换为ddI治疗后,研究HIV-1分离物的体外药物敏感性.
- 为了确定与药物敏感性改变相关的HIV-1逆转录酶的遗传突变.
- 评估特定突变对ddI和AZT耐药性概况的影响.
主要方法:
- 从五名患有获得性免疫缺陷综合征 (艾滋病) 的患者中收集了系列HIV-1分离物,这些患者正在接受治疗变化.
- 对于dDI和AZT进行了体外药物敏感性测试.
- 对HIV-1的逆转录酶编码区域进行了测序,以确定突变.
主要成果:
- 艾滋病毒-1分离体在ddI开始后的12个月内对ddI敏感性降低,对AZT敏感性增加.
- 在逆转录酶基因中发现了一种新的突变,与ddI敏感性降低相关.
- 这种突变,当与AZT耐药性突变一起存在时,导致AZT敏感性增加,并对ddI和ddC产生耐药性,同时抑制AZT耐药性的效应.
结论:
- 特定的HIV-1突变的出现可以在序列治疗期间改变药物耐药性概况.
- 一个单一的突变可以赋予对多种药物的耐药性,并调节其他耐药性突变的影响.
- 针对HIV-1的组合疗法可能对预防耐药病毒变异的出现至关重要.
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