每日一翻：Semen Protects HIV From Microbicide Attack

They were thought to have great promise in the fight to stop the spread of AIDS. Indeed, vaginal microbicides did a fine job killing HIV in the lab. But they failed to work in clinical trials.

杀微生物剂被认为在阻止艾滋病传播的战斗中大有作用。事实上，根据在实验室的研究证明，阴道杀菌剂对抵抗艾滋病病毒有很好的作用。

Now, researchers think they have identified the culprit: semen.

现在，研究者们认为他们已经鉴定出感染艾滋病罪魁祸首：精液。

In previous studies, scientists had looked at the HIV virus on cells protected by microbicides. But the latest tests evaluated microbicides in the more real-world situation where semen is present. And semen stopped the microbicides from working. Probably because semen contains protein fragments that help HIV to attach to cell surfaces and infect cells.

在先前的研究中，科学家观察了被杀微生物剂保护的细胞上附着的HIV病毒。但是最近的试验在更接近现实生活的有精液存在的情况下评估了杀微生物剂的作用。精液让杀微生物剂失效了。这很可能是因为精液包含能够帮助HIV病毒附着在细胞表面并且进入细胞中的蛋白质片段。

The research is in the journal Science Translational Medicine. [Onofrio Zirafi et al, Semen enhances HIV infectivity and impairs the antiviral efficacy of microbicides]

这项研究发表在《科学转化医学》期刊上。

There’s good news, though—a drug not currently used as a microbicide did seem to offer protection. It’s an antiretroviral called Maraviroc. Conventional microbicides target the virus itself. But Maraviroc binds to receptors on host cells. That action forms a barrier that prevents the HIV from attaching to the cell. Maraviroc is currently approved as an HIV drug, and is being considered as a microbicide to try to stop infection in the first place.

尽管目前似乎没有像杀微生物剂一样的药物来提供保护，但是这里有个好消息。那就是一种叫做Maraviroc的抗艾药。常规的杀微生物剂是针对病毒本身。而Maraviroc会与宿主细胞结合，这可以形成一个屏障，从而阻止艾滋病毒侵入细胞。Maraviroc是现在公认的抗艾滋病药物，并且正在被考虑当做杀微生物剂来在源头上阻止艾滋病的感染。

The research is a reminder that, in drug testing, context is crucial.

—Cynthia Graber