经济学人｜红细胞保存数年后还可再生？
Dehydrated blood that could be kept at room temperature for years may be possible thanks to a sugar used to preserve donuts—and made by tardigrades and brine shrimp so they can dry out and spring back with water.
Blood donations save lives. But blood can only be stored under refrigeration for up to six weeks. After that, it’s no longer usable for transfusions.
“Because of that limitation, people have to continually donate blood to meet the needs. But also, in places where refrigeration may not be available, that can also be a challenge. It’s difficult to have blood available when needed.”
University of Louisville bioengineer Jonathan Kopechek. He says disruptions to regular blood donations due to COVID-19 have put stress on the blood supply, and the pandemic underscores the need for more reliable long-term storage methods. Blood can be frozen for extended periods of time ...
“But it’s pretty rare because of all the challenges and complexities with that process.”
Instead Kopechek’s team has developed a method of preserving blood so it can be stored in a dehydrated state at room temperature. To do so, they turned to an unusual preservative: a sugar called trehalose, which is a common ingredient in donuts ...
“To help make them look fresh even when they might be months old, and you wouldn’t know the difference.”
The researchers chose trehalose because, in nature, it’s made by hardy animals like tardigrades and sea monkeys—aka brine shrimp—famous for their ability to survive dehydration.
“So these animals can dry out completely for a long period of time and then be rehydrated and resume normal function. So we wanted to use the trehalose that’s produced by these organisms and apply that to preserving blood cells in a dried state, just like those organisms are.”
But first, the researchers had to get trehalose into blood cells. They used ultrasound to drill temporary holes in the cell membranes—which let some trehalose get in.
“And they need to have sufficient levels of trehalose on both the inside and the outside of the cell in order to survive the dehydration and rehydration process.”
At that point, the blood could be dried and made into a powder.
“And then we can rehydrate the blood and have it return back to normal.”
The team is still trying to improve yields but thinks the dried blood could be stored at room temperature for years. The study is in the journal Biomicrofluidics. [Connor S. Centner et al., Ultrasound-induced molecular delivery to erythrocytes using a microfluidic system]
Kopechek says the technique could be ready for clinical trials in three to five years. If successful, it could be used to create stores of dried blood in case of future pandemics or natural disasters—and for humanitarian aid work, military operations or even missions to Mars. Maybe first aid kits on the Red Planet will include dried red blood cells.
---from Scientific American
重点词汇汇总:
Dehydrated /diːˈhaɪdreɪtɪd/adj. 脱水的
donut /ˈdoʊnʌt/n. 甜甜圈;炸面圈，多纳圈
brine shrimp盐水虾
bioengineer/'baiəu,endʒi'niə/n. 生物工程师
disruption /dɪsˈrʌpʃn/n. 扰乱，打乱，中断
underscore /,ʌndɚ'skɔr/n. 底线，[计] 下划线vt. 强调；划线于…下
trehalose/'trihəloz/n. [生化] 海藻糖
a common ingredient in donuts甜甜圈中常见的成分
ingredient /ɪnˈɡriːdiənt/n. 原料；要素；组成部分
hardy /ˈhɑːrdi/n. 强壮的人；耐寒植物；方柄凿adj. 坚强的；勇敢的；能吃苦耐劳的；鲁莽的
ultrasound /ˈʌltrəsaʊnd/n. 超声；超音波
membranes /mɛmbrens/n. 细胞膜（membrane的复数）；薄膜；膜皮
yields n. 生产量，投资效益（yield的复数形式）
erythrocyte /ɪˈrɪθrəsaɪt/n. [细胞] 红细胞；[细胞] 红血球
clinical trials临床试验 /ˈtraɪəl/
humanitarian aid 人道主义援助
humanitarian /hjuːˌmænɪˈteriən/ 人道主义者；慈善家；博爱主义者；基督凡人论者adj. 人道主义的；博爱的；基督凡人论的
百度翻译:
脱水的血液可以在室温下保存数年，这可能要归功于一种用来保存甜甜圈的糖，这种糖是由芋头和盐水虾制成的，这样它们就可以干燥，然后用水来恢复。
献血拯救生命。但血液只能冷藏6周。之后，它就不能再用于输血了。
“由于这一限制，人们必须不断献血以满足需要。但是，在一些没有制冷设备的地方，这也是一个挑战。需要时很难有血液供应。”
路易斯维尔大学生物工程师乔纳森·科佩切克。他说，由于COVID-19导致的定期献血中断，给血液供应带来了压力，而这场大流行病强调需要更可靠的长期储存方法。血液可以被冷冻很长一段时间。。。
“但这是非常罕见的，因为这一过程面临着各种挑战和复杂性。”
相反，Kopechek的团队已经开发出一种保存血液的方法，这样血液就可以在室温下以脱水状态储存。为此，他们转向了一种不寻常的防腐剂：一种叫做海藻糖的糖，它是甜甜圈中的一种常见成分。。。
“即使它们可能只有几个月大，也能让它们看起来很新鲜，而你不知道它们有什么区别。”
研究人员之所以选择海藻糖，是因为在自然界中，海藻糖是由耐寒的动物制成的，如缓步动物和海猴，又称盐水虾，它们因脱水而闻名。
“因此，这些动物可以完全干燥很长一段时间，然后再补充水分，恢复正常功能。因此，我们希望利用这些生物产生的海藻糖，并将其应用于保存处于干燥状态的血细胞，就像那些生物一样。”
但首先，研究人员必须将海藻糖注入血细胞。他们用超声波在细胞膜上钻临时孔，让海藻糖进入。
“他们需要在细胞内外都有足够的海藻糖水平，才能在脱水和再水化过程中存活下来。”
这时，血液可以被干燥并制成粉末。
“然后我们再给血液补水，让它恢复正常。”
研究小组仍在努力提高产量，但认为干血可以在室温下保存数年。这项研究发表在《生物微流体学》杂志上。【Connor S.Centner等人，使用微流控系统超声诱导的红细胞分子传递】
科佩切克说，这项技术可能在三到五年内为临床试验做好准备。如果成功的话，它可以用来制造干血库，以防将来发生大流行病或自然灾害，并用于人道主义援助工作、军事行动甚至火星任务。也许红色星球上的急救箱会包括干红细胞。