2022年经济学人 狡猾的细菌(2)（在线收听）

That finding alone is interesting, because it helps explain why cystic-fibrosis patients with bacterial infections often develop copious mucus in their lungs, even though this does nothing to counter the bacteria.

这一发现本身就很有趣，因为它有助于解释为什么患有细菌感染的囊性纤维化患者经常在肺部产生大量粘液，尽管这对于对抗细菌毫无作用。

More intriguing, though, was what happened when the researchers tried growing P.Aeruginosa on samples of this mucus.

然而，更有趣的是，当研究人员试图在这种粘液样本上培养铜绿假单胞菌时发生了的现象。

So long as LasB was present, the bacteria did not merely thrive, but actually consumed the mucus.

只要LasB存在，细菌不仅会茁壮成长，而且实际上还会消耗粘液。

Not only is P.Aeruginosa tricking the immune system into an inappropriate response, it is also feeding on the result.

铜绿假单胞菌不仅欺骗免疫系统，使其产生不恰当的反应，而且还以此为食。

And to make things worse still, Dr Medzhitov also discovered that all this immune manipulation makes the surrounding tissues prone to allergy.

更糟糕的是，梅德日托夫博士还发现，所有这些免疫操作都会使周围组织容易过敏。

Allergic reactions are, essentially, exaggerated and inappropriate type-2 immune responses.

过敏反应本质上是夸张和不恰当的2型免疫反应。

The researchers therefore wondered whether the reactions being created by LasB could cause lasting allergies to develop.

因此，研究人员想知道LasB产生的反应是否会导致持久的过敏反应。

To find out, they sprayed mice infected with P.Aeruginosa with egg-white protein (often used as an experimental allergen) on the first and seventh days of a four-week experiment.

为了找到答案，他们在为期四周的实验的第一天和第七天，向感染铜绿假单胞菌的小白鼠喷洒蛋清蛋白(通常用作实验性过敏原)。

As a control, they did the same with some mice genetically engineered to lack the ability to produce amphiregulin when exposed to LasB.

作为对照，他们对一些基因改造的小白鼠做了同样的实验，当暴露在LasB中时，小白鼠缺乏产生双性调节蛋白的能力。

They theorised that, in the absence of worms, the inflamed epithelial tissues in normal mice might instead identify the egg-white protein as an intruder.

他们推测，在没有蠕虫的情况下，正常小白鼠体内发炎的上皮组织可能会将蛋清蛋白识别为入侵者。

This is exactly what happened.

事情就是这样。

When injected with a small amount of egg-white protein two and three weeks after the start of the experiment, the normal mice showed a strong allergic response to it.

当实验开始两周和三周后，正常小白鼠被注射少量蛋清蛋白后，表现出强烈的过敏反应。

In contrast, the amphiregulin-free mice showed little.

相比之下，不含双调节蛋白的小白鼠几乎没有表现出过敏反应。

These discoveries, fascinating in and of themselves, also pave the way for new approaches to treating infections in those with cystic fibrosis.

这些发现本身就很极具吸引力，也为治疗囊性纤维症患者感染的新方法铺平了道路。

Moreover, if one bug has thus evolved a way to milk the immune system, the chances are good that others have done so too.

此外，如果一种细菌因此进化出了一种骗取免疫系统的方法，那么其他细菌也很有可能这样做。

Thus alerted, researchers will be on the lookout for similar cases.

因此，研究人员将警惕类似的情况。