埃博拉疫苗氣霧劑成功通過動物實驗

A single dose of a new Ebola vaccine that can be inhaled has been found to neutralize the deadly virus in Monkeys, researchers reported on Monday.

研究人員週一通報稱，已發現一種新的可吸入型埃博拉疫苗，只需一劑便可抵禦猴子體內的致命性病毒。

The study, published in the Journal of Clinical Investigation, demonstrated that the aerosol Ebola vaccine activated immune cells in the respiratory system of rhesus macaques and provided full protection against the virus. The study was conducted by researchers at The University of Texas Medical Branch in Galveston and the National Institutes of Health in Bethesda, Md. It was the first attempt to use an aerosol to vaccinate monkeys against a hemorrhagic viral fever, the study’s authors said.

發表在《臨牀調查雜誌》(Journal of Clinical Investigation)上的該論文證明，該氣霧型埃博拉疫苗激活了恆河猴呼吸系統內的免疫細胞，提供了針對該疫苗的完全防護。進行研究的是德克薩斯大學加爾維斯頓醫學分部(University of Texas Medical Branch in Galveston)和位於馬里蘭州貝塞斯達的美國國家衛生研究院(National Institutes of Health)的研究人員。文章作者稱，這是首次嘗試用氣霧劑給猴子接種防治病毒性出血熱的疫苗。

“The initial several decades of attempts to develop a vaccine against the Ebola virus were unsuccessful,” said Alexander Bukreyev, a virologist from the University of Texas Medical Branch and one of the paper’s authors. “This is one of the few vaccines that works.”

“最初幾十年研發埃博拉疫苗的嘗試都不成功，”來自德克薩斯大學加爾維斯頓醫學分部的病毒學家、論文的作者之一亞歷山大·布克列耶夫(Alexander Bukreyev)說。“這是少數有效的疫苗之一。”

But the success of the vaccine in monkeys is no guarantee that it will work in people. This year, an Ebola drug that had been effective in monkeys failed to help humans.

但在猴子身上的成功，不能保證該疫苗在人身上有效。今年，在猴子身上有效的一種藥物就未能幫到人類。

“This is a positive step forward,” said Dr. Daniel Bausch, a virologist from Tulane University. “It’s not a breakthrough or ‘Eureka!’ ”

“這是一個積極的進步，”來自杜蘭大學(Tulane University)的病毒學家丹尼爾·鮑施(Daniel Bausch)說。“但不是突破或‘找到啦’。”

The new vaccine can be administered without help from a medical professional. So if it proves successful in humans, the vaccine will be particularly useful in developing countries where there is a severe scarcity of doctors and nurses, as there is in West Africa, where the worst Ebola epidemic in history has yet to be extinguished.

這款新疫苗可以在沒有醫學專業人士幫助的情況下服用。因此如果證明在人身上有效，該疫苗在發展中國家會特別有用，因爲發展中國家嚴重缺乏醫生和護士。西非便是這種情況。在那裏，史上最嚴重埃博拉疫情尚未被消除。

“The discussion in the field right now is if this Ebola outbreak will be some kind of game changer for vaccine development, or will it only be one more scare that will be forgotten,” said Dr. Igor Lukashevich, a medical virologist from the University of Louisville, who was not involved with the study. “This aerosolized form of the vaccine is really what the field needs right now.”

“目前，這個領域討論的是，這一輪埃博拉疫情是會讓疫苗研究發生翻天覆地的變化，還是隻會成爲又一場將被遺忘的恐慌，”未參與這項研究的路易斯維爾大學(University of Louisville)醫學病毒學家伊戈爾·盧卡舍維奇(Igor Lukashevich)說。“這種氣霧形態的疫苗真的是這個領域目前所需要的。”

The study’s lead author, Michelle Meyer, a postdoctoral fellow at the University of Texas Medical Branch, said the respiratory tract may serve as a portal for the Ebola virus if it is exposed to droplets of infected bodily fluids.

論文的第一作者、德克薩斯大學加爾維斯頓醫學分部博士後米歇爾·梅耶爾(Michelle Meyer)表示，如果接觸了幾滴被感染的體液，呼吸道可能會成爲埃博拉病毒的入口。

In the study, the aerosol vaccine generated substantially more Ebola-immunity cells in the lungs than in the blood and spleen. The cells “in the lungs are acting as the first barrier for protection,” Dr. Meyer said. “That’s ideal to combat the virus at the site of infection.”

研究發現，該氣霧型疫苗在肺中產生的埃博拉免疫細胞，遠多於血液和脾。“肺裏的這些細胞充當着第一道保護屏障，”梅耶爾說。“在感染的地方阻擊病毒是最好的。”

Four of the rhesus macaques used in the research were given one dose of the aerosol vaccine; four were given two doses; and two were given the vaccine in a liquid form. Two monkeys were not vaccinated, serving as controls.

在研究使用的恆河猴中，四隻服用了一劑該氣霧型疫苗，四隻服用了兩劑，兩隻服用了液態形式的該疫苗。還有兩隻未接種疫苗，充當着控制組的研究對象。

Four weeks after their treatments, all 12 monkeys were injected with 1,000 times the fatal dose of the Ebola virus. A little over a week later, the two unvaccinated monkeys succumbed to the disease and were euthanized, but the vaccinated monkeys stayed healthy. At the end of the study, the researchers euthanized the surviving monkeys, examined their blood and tissues, and found no traces of the Ebola virus.

四周後，12只猴子體內全被注入了1000倍於致死劑量的埃博拉病毒。一週多一點後，那兩隻未接種疫苗的猴子被該病毒感染，接受了安樂死，但接種了疫苗的猴子依然很健康。最後，研究人員對倖存下來的猴子實行了安樂死，並對它們的血液和組織進行了檢查，未發現埃博拉病毒的蹤跡。

“One aerosol dose of our vaccine was able to protect these animals from death and severe disease,” Dr. Meyer said.

“一劑氣霧型疫苗就能防止這些動物死亡和重病，”梅耶爾說。

The next step will be for the team’s colleagues at the National Institutes of Health to perform clinical trials of the vaccine on humans.

下一步，國家衛生研究院的研究人員將對該疫苗進行人體臨牀試驗。