研究:精液可能有助于预防女性感染艾滋病毒

研究:精液可能有助于预防女性感染艾滋病毒

Repeated exposure to semen can alter vaginal tissue immune cells that are prime targets for HIV, reducing chances of infection, according to new research out of Philadelphia’s Wistar Institute and the University of Puerto Rico.

费城威斯塔研究所(Wistar Institute)和波多黎各大学(University of Puerto Rico)的一项新研究显示，反复接触精液可以改变阴道组织的免疫细胞，从而降低感染几率。阴道组织免疫细胞是艾滋病病毒的主要目标。

The sprawling list of co-authors on the ambitious study — which was supported by the National Institutes of Health and other top AIDS research agencies — also hail from the University of Nebraska, Duke University, Mount Holyoke College, Ulm University, the University of Pennsylvania and Tulane University.

这项雄心勃勃的研究得到了美国国立卫生研究院和其他顶尖艾滋病研究机构的支持，研究报告的众多合著者还来自内布拉斯加大学、杜克大学、曼荷莲学院、乌尔姆大学、宾夕法尼亚大学和杜兰大学。

The findings, published Tuesday in the journal Nature Communications, could explain why a small number of female sex workers worldwide continue to test negative despite continuous high-risk intercourse.

周二发表在《自然通讯》(Nature Communications)杂志上的这一研究结果，可以解释为什么世界范围内的一小部分女性性工作者，在持续高风险性交的情况下，仍然检测结果呈阴性。

Previous research published in 2015 revealed that semen exposure resulted in changes in prostitutes’ cervicovaginal tissue, suggesting increased resistance to HIV infection.

2015年发表的之前的研究显示，暴露在精液中会导致妓女的宫颈阴道组织发生变化，这表明她们对艾滋病毒感染的抵抗力增强了。

The new study, however, directly investigated if semen is indeed a factor in resistance.

然而，这项新研究直接调查了精液是否确实是抗药性的一个因素。

“While HIV infection has been with us for more than 30 years, this is the first study that describes how semen exposure over time could result in local tissue changes that limit HIV infection in humans,” Wistar scientist Luis J. Montaner, lead author of the study, told Scienmag. “Apart from defining a new factor that may regulate HIV transmission, this unexpected finding could directly impact the design of future HIV vaccine studies that commonly recruit female sex workers.”

Wistar科学家路易斯·j·蒙塔纳(Luis J. Montaner)是这项研究的主要作者，他在接受《科学》杂志采访时表示:“尽管艾滋病病毒感染已经存在了30多年，但这是第一项描述精液长期接触，会导致局部组织变化从而限制人类感染艾滋病病毒的研究。”“除了确定一个可能调控艾滋病毒传播的新因素，这一意外发现还可能直接影响未来艾滋病毒疫苗研究的设计，这些研究通常会招募女性性工作者。”

Montanter added, “Currently, condomless sex is assumed to only promote the likelihood of infection. Our observation, however, raises the hypothesis that frequent semen exposure may potentially reduce HIV transmission.”

蒙坦特补充说:“目前，无安全套性交被认为只会增加感染的可能性。然而，我们的观察提出了一个假设，频繁的精液接触可能会减少艾滋病毒的传播。”

Edmundo N. Kraiselburd, a professor at the University of Puerto Rico, co-directed the pre-clinical research project and supervised the use of macaque primates from the Caribbean Primate Research Center to test prophylactic anti-HIV interventions.

波多黎各大学(University of Puerto Rico)教授埃德蒙多·n·克雷斯伯德(Edmundo N. Kraiselburd)参与指导了这项临床前研究项目，并监督加勒比灵长类动物研究中心(Caribbean Primate research Center)使用猕猴来测试预防性的抗艾滋病干预措施。

“This research clearly shows the valuable information the macaque model can provide when used to study what may determine HIV infections in humans,” said Kraiselburd.

Kraiselburd说:“这项研究清楚地表明，猕猴模型可以提供有价值的信息，用于研究可能决定人类感染艾滋病毒的因素。”

The primates were exposed to semen twice a week over five months with or without inactivated particles of the simian immunodeficiency virus (SIV is an HIV-like virus that infects primates, causing a disease similar to AIDS). After this “conditioning period,” they received low doses of intravaginal SIV.

在五个月的时间里，这些灵长类动物每周两次接触精液，精液中含有或不含有猿类免疫缺陷病毒(SIV是一种类似hiv的病毒，会感染灵长类动物，导致一种类似艾滋病的疾病)的灭活颗粒。在这个“适应期”之后，他们接受了低剂量的阴道内SIV。

The semen-exposed monkeys showed a 42 percent decrease in the risk of infection.

精液暴露的猴子感染的风险降低了42%。

The repeated semen exposure resulted in elevated cervicovaginal tissue levels of antivirals such as MX1, which also positively correlated with levels of what’s called IFN-epsilon. IFN-epsilon, which can be induced by semen and protects human cells from bacterial and viral pathogens, has “direct anti-HIV properties and was described to be induced in tissues from sex workers in association with condomless sex.”

反复的精液暴露导致MX1等抗病毒药物的颈阴道组织水平升高，这也与被称为IFN epsilon的水平呈正相关。ifn epsilon，可以由精液诱导，保护人体细胞免受细菌和病毒病原体的侵害，具有“直接的抗艾滋病特性，并被描述为在组织中由性工作者诱导，与无行为能力的性行为有关”。

But whether this is good news for the 17.4 million women living with HIV — 51 percent of the global total, according to the World Health Organization — is still very unclear.

但是，据世界卫生组织统计，这是否对1740万感染艾滋病毒的妇女——占全球总数的51%——是否是个好消息，仍然不清楚。

Primates that remained uninfected after exposure to low viral amounts became infected when later challenged with high virus doses.

灵长类动物在接触低病毒量的病毒后仍然没有感染，但后来受到高病毒量的挑战时就感染了。

The scientists’ bottom line: Repeated semen exposure provides partial protection — but does not block HIV infection.

科学家的结论是:重复的精液暴露提供了部分保护，但不能阻止HIV感染。

“Importantly, we show that semen exposure can promote host resistance but does not protect against infection,” said Montaner. “Therefore, our data do not change the fact that prevention methods, such as condom use and PrEP (pre-exposure prophylaxis) remain our best strategies to prevent infection.”

蒙塔纳说:“重要的是，我们证明，精液暴露可以促进宿主的抵抗力，但不能防止感染。”“因此，我们的数据并没有改变这样一个事实，即使用避孕套和预防(接触前预防)等预防方法仍然是我们预防感染的最佳策略。”