With over a hundred thousand people waiting for an organ transplant in the US alone, scientists are racing to find options besides human donors. Now for the first time, a pig kidney has been successfully transplanted into a person.

仅在美国，就有数百万人在等待器官移植，因此科学家们都在竞相寻找除人体捐赠者之外的其他选择方案。日前，一颗猪肾首次成功植入人的体内。

The operation to attach the kidney. (Joe Carrotta/NYU Langone Health)

When we say "successfully", it was only tested for 54 hours in a human patient – a patient who was already brain dead and being kept alive artificially. But as far as the transplant team could see, the kidney was connected and functioning normally during that time.

我们所说的“成功”是指被植入的猪肾目前仅在人体中植入了54个小时-患者已经脑死亡并靠人工方式保持存活。但是，就移植团队而言，在这段时间内，猪肾已经与被植入者的身体正常连接并发挥作用。

Technically, this is known as xenotransplantation, or the transplanting of tissues or organs from one species to another. If the work pioneered here can be developed, pigs could provide an abundance of organs suitable for use in people who need them. Currently, an average of 17 people die on transplant waiting lists per day in the US.

从技术角度来看，这种移植也被称为异种移植，或将一个物种的细胞或器官移植到另一个物种体内。如果这项创新的工作能够被进一步推动，那么猪可以为人类提供大量适合使用的器官。目前，在美国等待器官移植的名单中，平均每天就会17个人死去。

Xenotransplantation：异种移植

"This is a huge breakthrough," Dorry Segev, professor of transplant surgery at Johns Hopkins School of Medicine, who was not involved in the research, told the New York Times. "It's a big, big deal."

“这是一项巨大的突破，”Dorry Segev，约翰霍普金斯医学院移植外科教授表示。Dorry本人并未参与研究。他本人在接受《纽约时报》采访时表示：“这件事意义重大。”

There are still plenty of hurdles to overcome, including regulatory approval, but using organs from other animals in this way could also help the hundreds of thousands of people who aren't considered at risk enough to get a transplant, but who have to deal with demanding kidney dialysis procedures.

目前还有许多的困难需要克服，包括获得监管审批。但是，使用其他动物体内的器官可能会帮助致数百万病情并非十分危重的患者也获得器官移植，但是他们需要面对要求严格的肾透析过程。

Organs from pigs have long been considered as potentially suitable for humans, but pig cells include a sugar called alpha-gal, which triggers an immediate rejection by the human body. In this case, the pig had been genetically engineered to not produce alpha-gal.

猪的器官很久以来就被认为有可能适合人类，但是猪的细胞中包含一种称为半乳糖甘酵素的糖，这种成分会立刻触发人体抵抗。在这种情况下，猪需要进行基因改造以使其不会产生半乳糖甘酵素。

alpha-gal：半乳糖甘酵素

While the pig kidney was kept outside of the body of the patient, it was observed to be doing its job during the operation: that is, filtering out waste products from the blood and producing urine.

尽管猪肾还在患者体外，但是在手术过程中，医生观察到猪肾会过滤血液中的废物并产生尿。

"It's even better than I'd hoped," surgeon Robert Montgomery, who led the transplant at NYU Langone Health in New York City, told USA Today.

在纽约市纽约大学Langone健康医学院负责移植的外科医生Robert Montgomery告诉《今日美国》：“这甚至比我希望的还要好。”

As yet, there's no peer-reviewed scientific report of the operation, but we can be cautiously optimistic. Experts say trials with pig kidneys on critically ill humans – patients with no real other options left – could happen within two years.

迄今为止，关于手术还没有同行评审的科学报告，但是我们持谨慎乐观的态度。专家表示，使用猪肾对病情危重的患者（没有其他可选办法的患者）进行试验可能会在2年内实现。

There are ethical concerns to consider though. While the family of the human patient in this test gave their consent to it, not everyone is comfortable with the idea of breeding animals specifically to harvest their organs.

需要考虑的还有道德担忧。尽管患者家属同意试验，但是并非所有人都能接受饲养动物就是为了使用它们的器官这一想法。

What might make organs from pigs more acceptable than organs from other animals – such as monkeys – is that pigs are already bred for food. They have large litters, short gestation periods, and organs that are similar to the ones we have.

猪的器官比其他动物的器官，比如猴子，更容易被人体接受的原因可能是因为人们在很久以前就开始养猪并将猪作为食物。猪每次的产仔数量大，妊娠期短，器官也和我们的器官更加相似。

We're already using pig skin grafts for burns and pig heart valves in humans, and experiments have already been carried out with pig hearts in baboons, so there is something of a precedent. Expect to hear much more about the potential of using pig organs inside humans in the years to come.

我们已经使用猪皮移植来治疗患者烧伤的皮肤并将猪的心脏瓣膜用于人类患者。将猪的心脏用于狒狒的实验已经开始进行，因此算有一些先例。在未来的数年里，我们期待了解更多关于将猪的器官应用于人体的可能性。

heart valve：心脏瓣膜

"This is an important step forward in realizing the promise of xenotransplantation, which will save thousands of lives each year in the not-too-distant future," Martine Rothblatt, the chief executive of United Therapeutics – the company that genetically engineered the pig – told The Guardian.

Martine Rothblatt，联合治疗（一家对猪进行基因改造的公司）首席执行官告诉《卫报》，“这次的尝试朝异种移植的实现又迈进一步。在不远的将来，这种移植方法每年将拯救数千万人的生命。”

来源：Science Alert   编辑&翻译：上海译锐翻译