研究:精液可能有助于預防女性感染艾滋病毒

研究:精液可能有助于預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.

費城威斯塔研究所(Wistar Institute)和波多黎各大學(University of Puerto Rico)的一項新研究顯示，反復接觸精液可以改變陰道組織的免疫細胞，從而降低感染幾率。陰道組織免疫細胞是艾滋病病毒的主要目標。

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.

這項雄心勃勃的研究得到了美國國立衛(wèi)生研究院和其他頂尖艾滋病研究機構的支持，研究報告的眾多合著者還來自內布拉斯加大學、杜克大學、曼荷蓮學院、烏爾姆大學、賓夕法尼亞大學和杜蘭大學。

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.

周二發(fā)表在《自然通訊》(Nature Communications)雜志上的這一研究結果，可以解釋為什么世界范圍內的一小部分女性性工作者，在持續(xù)高風險性交的情況下，仍然檢測結果呈陰性。

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

2015年發(fā)表的之前的研究顯示，暴露在精液中會導致妓女的宮頸陰道組織發(fā)生變化，這表明她們對艾滋病毒感染的抵抗力增強了。

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

然而，這項新研究直接調查了精液是否確實是抗藥性的一個因素。

“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科學家路易斯·j·蒙塔納(Luis J. Montaner)是這項研究的主要作者，他在接受《科學》雜志采訪時表示:“盡管艾滋病病毒感染已經(jīng)存在了30多年，但這是第一項描述精液長期接觸，會導致局部組織變化從而限制人類感染艾滋病病毒的研究。”“除了確定一個可能調控艾滋病毒傳播的新因素，這一意外發(fā)現(xiàn)還可能直接影響未來艾滋病毒疫苗研究的設計，這些研究通常會招募女性性工作者。”

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.”

蒙坦特補充說:“目前，無安全套性交被認為只會增加感染的可能性。然而，我們的觀察提出了一個假設，頻繁的精液接觸可能會減少艾滋病毒的傳播。”

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.

波多黎各大學(University of Puerto Rico)教授埃德蒙多·n·克雷斯伯德(Edmundo N. Kraiselburd)參與指導了這項臨床前研究項目，并監(jiān)督加勒比靈長類動物研究中心(Caribbean Primate research Center)使用獼猴來測試預防性的抗艾滋病干預措施。

“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說:“這項研究清楚地表明，獼猴模型可以提供有價值的信息，用于研究可能決定人類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.

在五個月的時間里，這些靈長類動物每周兩次接觸精液，精液中含有或不含有猿類免疫缺陷病毒(SIV是一種類似hiv的病毒，會感染靈長類動物，導致一種類似艾滋病的疾病)的滅活顆粒。在這個“適應期”之后，他們接受了低劑量的陰道內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風險降低了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.”

反復的精液暴露導致MX1等抗病毒藥物的頸陰道組織水平升高，這也與被稱為IFN epsilon的水平呈正相關。ifn epsilon，可以由精液誘導，保護人體細胞免受細菌和病毒病原體的侵害，具有“直接的抗艾滋病特性，并被描述為在組織中由性工作者誘導，與無行為能力的性行為有關”。

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，據(jù)世界衛(wèi)生組織統(tǒng)計，這是否對1740萬感染艾滋病毒的婦女——占全球總數(shù)的51%——是否是個好消息，仍然不清楚。

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

靈長類動物在接觸低病毒量的病毒后仍然沒有感染，但后來受到高病毒量的挑戰(zhàn)時就感染了。

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

科學家的結論是:重復的精液暴露提供了部分保護，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.”

蒙塔納說:“重要的是，我們證明，精液暴露可以促進宿主的抵抗力，但不能防止感染。”“因此，我們的數(shù)據(jù)并沒有改變這樣一個事實，即使用避孕套和預防(接觸前預防)等預防方法仍然是我們預防感染的最佳策略。”