評論
打印
Science and technology
科學技術
Combating addiction
抵抗毒癮
Can a vaccine stop drug abuse?
有抗毒品的疫苗么？
It may be possible to vaccinate people against addictive drugs
也許通過接種疫苗幫助人們擺脫毒癮將成為可能
THE idea of vaccinating drug addicts against their affliction is an intriguing one.
給癮君子注射疫苗以幫助他們擺脫痛苦是一個非常有趣得想法。
In principle, it should not be too hard.
原則上，這并不難。
The immune system works, in part, by making antibodies that are specific to particular sorts of hostile molecule.
在某種程度上，免疫系統針對某些有害分子產生抗體來實現運作。
Such antibodies recognise and attach themselves to these molecules, rendering them harmless.
抗體可以識別這些分子并將自己與它們粘附在一起使得它們無害化。
Vaccines work by presenting the immune system with novel targets, so that it can learn to react to them if it comes across them again.
接種疫苗就是通過向免疫系統提供新的目標，這樣當免疫系統下次遇到這些目標時就會知道如何應對。
The problem is that the molecules antibodies recognise and react to are the big ones,
問題在于抗體能夠識別并作出反應的分子都是像蛋白質這樣的大分子，
such as proteins, that are characteristic of bacteria, viruses and other infectious agents.
這些分子是細菌，病毒以及其他傳染介質的特性。
Small molecules, such as drugs, go unnoticed.
而像藥品這樣的小分子卻不會被注意到。
But not for much longer, if Kim Janda of the Scripps Research Institute in San Diego has his way.
但是如果來自圣地亞哥，斯克里布斯研究所的吉姆·簡達的研究工作一帆風順的話，這種情況將不會持續太久。
In a paper just published in the Journal of the American Chemical Society, Dr Janda and his colleagues suggest how a vaccine against methamphetamine, a popular street drug, might be made.
在剛剛發表在《美國化學協會期刊》上的論文中，簡達博士指出一種針對甲基苯丙胺的疫苗將出現。
If their method works, it would open the possibility of vaccinating people against other drugs, too.
如果他們的方法可行，開發針對其他毒品的疫苗將成為可能。
The idea of a methamphetamine vaccine is not new.
甲基苯丙胺疫苗不算出新。
The problem is getting the immune system to pay attention to a molecule that is such a small target.
問題是讓免疫系統注意到這么小的一個目標。
The way that has been tried in the past is to build the vaccine from several components.
過去所嘗試過的方法是讓疫苗的組成成分多樣化。
First, there is a large carrier protein that forms a platform for the target.
首先，需要建立一個大型蛋白質載體以作為目標平臺。
Then there is the target itself, a set of smaller molecules called haptens that are attached to the carrier.
在有了目標之后，再將一系列叫做半抗原的小分子附屬在載體上。
These may either be the drug in question or some analogue of it that, for one reason or another, is reckoned to have a better chance of training the immune system.
這些半抗原既可以是毒品本身也可以是毒品的類似物質從而更好地引起免疫系統的注意。
Finally, there is a chemical cocktail called an adjuvant that helps get the immune system to pay attention to the carrier protein and the haptens.
最后，一個叫做輔助劑的化學品混合體可以幫助免疫系統注意到蛋白質載體和這些半抗原。
Dr Janda noticed that past experiments on methamphetamine vaccines had all revolved around tweaking either the carrier protein or the adjuvant,
簡達博士注意到過去對于甲基苯丙胺疫苗的試驗總是圍繞著蛋白質載體或者輔助劑在進行，
rather than tinkering with the haptens.
而忽略了半抗原。
He thought he might be able to change that, on the basis of work he had carried out previously, trying to design a vaccine against nicotine.
他認為基于之前為設計一種尼古丁疫苗而開展的研究，他將改變這一狀況。
In particular, nicotine is a highly flexible molecule.
特別是尼古丁的分子存在很高的變化性。
That makes it hard for the immune system to recognise.
這使得免疫系統難以識別他們。
To overcome this, his team on the nicotine project had to work out how to fix their haptens to the carrier protein in a way that rendered them less capable of twisting and turning, and thus made them easier for the immune system to identify.
為了克服這一問題，其尼古丁疫苗項目團隊必須找到如何將半抗原固定在蛋白質載體上的方法，使得這些分子不那么容易扭曲轉動，從而更容易被免疫系統識別。
In the new study, Dr Janda and his colleagues report that they have performed a similar trick with methamphetamine haptens.
在新的研究中，簡達博士和他的同事們報告稱他們針對甲基苯丙胺采取了相同的處理方法。
They used computer models to visualise the haptens in three dimensions and thus work out how the molecules could be rearranged such that they could not spring, twist or turn when being examined by the immune system.
他們使用電腦模型來呈現半抗原的3D圖像并且解決了如何重新安排分子位置以使得其在被免疫系統檢查時不會突然活動，扭曲或者轉動。
In light of this information they designed six new methamphetamine-like haptens.
鑒于這些信息，他們設計了6種新的類似于甲基苯丙胺的半抗原。
Once built, they attached the new hapten molecules to carrier proteins, mixed them with adjuvant, injected the results into mice and waited.
在半抗原成形后，他們將這些新的半抗原分子附到蛋白質載體上并與輔助劑混合再注射到小鼠身上等待結果。
After several weeks they tested the mice to see if the animals'blood contained antibodies to methamphetamine.
幾周后，他們對小鼠進行檢查看這些動物的血液中是否含有甲基苯丙胺的抗體。
Of the six new haptens, three successfully provoked the mice to make such antibodies.
在這6種新的半抗原中有3種成功在小鼠體內產生了抗體。
As a bonus, one of those three also stimulated the production of antibodies against another widely used drug, amphetamine.
作為額外收獲，其中1種還產生了另一種被廣泛使用的毒品—安非他命（苯丙胺）的抗體。
That is still a long way from providing a working vaccine, but it is an important step forward.
雖然離獲得一種真正奏效的疫苗還有很長一段路要走，但是這也算是向前邁出的重要一步。
And if human immune systems react in the same way to the new vaccines as murine ones do,
如果人類的免疫系統可以像鼠科動物那樣對于新疫苗產生同樣的反應，
the day when a drug addict might be offered vaccination rather than opprobrium will have come a little closer.
那么離癮君子們獲得疫苗而不是羞辱的那一天又近了一步。
