2022年经济学人 川大教授开发血小板膜涂层避免了支架排异(2)（在线收听）

Stents are used by heart surgeons to open up blood vessels that have got clogged.

心脏外科医生可用支架打开堵塞的血管。

They are extremely effective at keeping people alive, but do attract the attention of the immune system, causing inflammation of the tissues around them, which results in scarring.

它们在维持人的生命方面非常有效，但确实会吸引免疫系统的注意，导致周围组织发炎，从而导致疤痕形成。

If enough scar tissue forms, that can itself impede blood flow.

如果形成了足够多的疤痕组织，就会阻碍血液流动。

Worse, it can result in part of the scar breaking off and causing a stroke or pulmonary embolism.

更糟糕的是，它可能导致部分疤痕脱落，导致中风或肺血栓。

Over the past two decades, types of stent have been designed that slowly release anti-inflammatory drugs and so reduce these risks.

在过去的二十年里，设计的支架类型可以缓慢释放抗炎药物，从而降低这些风险。

But success is not guaranteed, and the consequences of failure are severe.

但不能保证成功，失败的后果是严重的。

The team coated their experimental stents by dipping them in a solution of dopamine and a substance called sodium periodate.

研究小组将他们的实验支架浸泡在多巴胺和高碘酸钠溶液中，从而可以在支架上涂上一层。

They then charged the coated stent to an appropriate negative voltage and dropped a suspension of “platelet-derived extracellular vesicles” (small bubbles of membrane that platelets can be induced to cough up by appropriate treatment) onto it, before incubating it at 37°C for a couple of hours.

然后，他们将涂层支架充电到适当的负电压，并在支架上滴上一层“血小板衍生的细胞外囊泡”(通过适当的处理可以诱导血小板咳出的小膜泡)，然后在37℃下孵育几个小时。

This done, examination with a microscope indicated that the stent was indeed covered in platelet membrane.

显微镜检查表明，支架确实被血小板膜覆盖。

But, to be sure the immune-shielding proteins were still there, the team used two special techniques, immunofluorescence and western blotting, to check for their presence.

但是，为了确保免疫屏蔽蛋白仍然存在，研究小组使用了两种特殊技术--免疫荧光和蛋白质印迹法--来检查它们是否存在。

The acid test, however, was to try out the stents in animals.

然而，关键的测试是在动物身上试验支架。

To that end they picked a group of rabbits and implanted into their abdominal aortas stents which had no coating, stents coated only in polydopamine, and stents which had also had platelet membranes attached to them.

为此，他们挑选了一组兔子，将没有涂层的支架、只涂有聚多巴胺的支架和有血小板膜附着的支架植入它们的腹主动脉。

After eight hours, they removed some of the stents and looked for a build-up of inflammatory cells.

八个小时后，他们取出了一些支架，并寻找炎性细胞的积聚。

They left the rest in place, allowed the animals to recover from the surgery, and then let them go about their lives for a month before killing them and collecting their stents for analysis.

其余的继续保留，让动物从手术中恢复过来，然后让它们继续生活一个月，然后杀死它们，收集它们的支架进行分析。

As expected, even after eight hours, let alone a month, the uncoated and the polydopamine-coated stents were saturated in cell growth triggered by immune activity.

正如预期的那样，即使在八个小时后，未涂层支架和多巴胺涂层支架在免疫活动引发的细胞生长中已经饱和，更不用说一个月了。

On both occasions, however, the membrane-coated stents were clean.

然而，在这两种情况下，覆膜支架都是干净的。

Translating this preliminary result in rabbits into a clinical application in human beings will be a hard graft, as it were.

可以说，将这一在兔子身上的初步结果转化为对人类的临床应用将是一项艰巨的嫁接。

How long the coating will last remains unknown.

涂层将持续多长时间尚不清楚。

And rabbits are not people, so the details of their physiologies are different.

兔子不是人，所以它们的生理细节是不同的。

But as a start, Dr Wang’s work is remarkable, for it opens a whole, new avenue of investigation into the problem of sustaining medical implants.

但首先，王博士的工作成果是显著的，因为它为研究维持医疗植入物的问题开辟了一条全新的途径。