Could RNA Drugs Defeat Ebola Virus

At first , people infected with the Ebola virus appear to have the flu-fever , chills , muscle aches .

Then the bleeding begins .

As the virus hijacks cells throughout the body to make copies of itself , it overwhelms and damages the liver , lungs , spleen and blood vessels .

Within days organs begin to fail and many patients fall into a coma .

Some outbreaks , primarily in Central and West Africa , have killed up to 90 percent of infected individuals .

That terrifying prognosis may be about to change .
prognosis: 予後、予知、予測

Using so-called small interfering RNA , or siRNA , Thomas W. Geisbert , now at the University of Texas Medical Branch at Galveston , and his many collaborators have devised a highly promising treatment that has saved the lives of six monkeys infected with the virus .
devised: deviseの過去形、または過去分詞。工夫する、 考案する、 案出する、 発明する

As reported this past January , the treatment has also passed its first safety test in an uninfected human volunteer .

One of Geisbert's collaborators , Ian Maclachlan of Burnaby , British Columbia\u2013based Tekmira Pharmaceuticals , and his team have received a $140-million grant from the U.S. Department of Defense to develop the therapy further .

Working together , the scientists engineered an siRNA to prevent the Ebola virus from making a particular protein , without which it cannot replicate itself .

If you knock out that one , in theory you knock out everything , Geisbert says .

The researchers also designed another siRNA to thwart manufacture of a second protein that the virus uses to weaken an infected individual's immune system .
thwart: 妨害する、じゃまする、(…に)反対する

There is no danger of the siRNAs interfering with typical cellular duties because the targeted viral proteins do not exist in the cells of humans or other mammals .
interfere with: 障る、構う、妨害する、じゃまをする、抵触する、邪魔する、障る

Maclachlan and his colleagues encapsulated the lab-made siRNAs in little bubbles of fat that cells would readily transport across their membranes .
encapsulated: encapsulateの過去形、または過去分詞。(…を)カプセルに包む、 さやに入れる
little bubbles: Null
membranes: membraneの複数形。(薄)膜

Then they injected the preparation into several rhesus macaques , which had been infected with Ebola virus less than an hour earlier .
preparation: 準備(すること)、(将来に向けての)用意の手はず、準備万端、調剤、調理、調合、調剤薬、調理食品、調合化粧品、宿題
rhesus: アカゲザルの
macaques: macaqueの複数形。マカク

In one study , two of three monkeys given a total of four doses of the treatment in the first week after exposure survived .
after exposure: 後露光

In a second study designed to test the effectiveness of a higher dose , all four monkeys that received seven siRNA injections lived .
designe to: 《be ～》～するように作られて［設計されて・考案されて・工夫されて・意図されて］いる、～するために策定｛さくてい｝される、～することを目的｛もくてき｝とするものである

Tests revealed that the treated monkeys had far fewer virus molecules in their blood than is typical for an infected animal .
far fewer: ～よりはるかに少ない犯罪｛はんざい｝

The macaques tolerated the siRNA injections well , and those that survived were still healthy 30 days later .
tolerated: tolerateの過去形、または過去分詞。(…を)大目に見る、 黙って許す、 寛大に取り扱う

The study was a milestone , says Gary Kobinger of the University of Manitoba , who is working on a different Ebola treatment based on antibodies .

He believes Geisbert and his team are leading the effort toward clinical development .

SCIENTIFIC AMERICAN ONLINEWatch an animation of short RNAs at work in the cell at ScientificAmerican .

com/apr2014/rna