A 3D printing technique that produces clusters of stem cells could speed up progress towards the creation of artificial organs， scientists claim. wa

In the immediate future it could be used to generate biopsy-like tissue samples for drug testing.

The technique relies on an adjustable “microvalve” to build up layers of human embryonic stem cells （hESCs）.

Altering the nozzle diameter precisely controls the rate at which cells are dispensed.

Lead scientist Dr. Will Shu， from Heriot-Watt University in Edinburgh， said， “We found that the valve-based printing is gentle enough to maintain high stem cell viability， accurate enough to produce spheroids of uniform size， and most importantly， the printed hESCs maintained their pluripotency—the ability to differentiate into any other cell type.” Embryonic stem cells， which originate from early stage embryos， are blank slates with the potential to become any type of tissue in the body.

The research is reported in the journal Biofabrication.

In the long term， the new printing technique could pave the way for hESCs being incorporated into transplant-ready laboratory-made organs and tissues， said the researchers.

The 3D structures will also enable scientists to create more accurate human tissue models for drug testing.

Cloning technology can produce embryonic stem cells， or cells with ESC properties， containing a patients own genetic programming.

Artificial tissue and organs made from such cells could be implanted into the patient from which they are derived without triggering a dangerous immune response.

Jason King， business development manager of stem cell biotech company Roslin Cellab， which took part in the research， said， “Normally laboratory grown cells grow in 2D but some cell types have been printed in 3D. However， up to now， human stem cell cultures have been too sensitive to manipulate in this way.”

“This is a scientific development which we hope and believe will have immensely valuable long-term implications for reliable， animal-free， drug testing， and， in the longer term， to provide organs for transplant on demand， without the need for donation and without the problems of immune suppression and potential organ rejection.”

科學(xué)家稱，現(xiàn)在可以用3D打印技術(shù)批量制造出干細(xì)胞，這一技術(shù)將能加速實現(xiàn)打印人造器官的進(jìn)程。

在不久的未來，這種3D打印技術(shù)可以用來制造類活組織物質(zhì)，作為藥物測試的樣品。

該技術(shù)依靠可調(diào)節(jié)的“微型閥”來制造出一層層的人體胚胎干細(xì)胞。

通過改變噴嘴直徑可精確地控制干細(xì)胞產(chǎn)出的速度。

來自愛丁堡赫瑞瓦特大學(xué)的首席科學(xué)家威爾·休博士說：“我們發(fā)現(xiàn)，這個依靠閥調(diào)節(jié)的打印技術(shù)很溫和，能保持干細(xì)胞的高存活率，也能準(zhǔn)確地制造出大小一致的球狀體，最重要的是，打印出的人體胚胎干細(xì)胞能保持它們的多能性，即分化成其他類型細(xì)胞的潛能?！痹醋栽缙谂咛サ呐咛ジ杉?xì)胞就像一塊白板，有潛能成為身體內(nèi)任何一種組織。

這一研究報告發(fā)表在《生物制造》雜志上。

研究人員表示，從長遠(yuǎn)來看，這一新的打印技術(shù)將為人體胚胎干細(xì)胞用于實驗室制造的可移植人體器官和組織鋪平道路。

3D打印出的人造器官還能讓科學(xué)家制造出更準(zhǔn)確的人體組織模型，它們可以用于藥物測試。

克隆技術(shù)可以制造出包含病人自身遺傳基因的胚胎干細(xì)胞，或具備胚胎干細(xì)胞性能的細(xì)胞。

用這種細(xì)胞制造出來的人造組織和器官可以被移植到原細(xì)胞所有者體內(nèi)，而不會引發(fā)危險的免疫反應(yīng)。

參與這一研究的干細(xì)胞生物科技公司Roslin Cellab的業(yè)務(wù)發(fā)展經(jīng)理杰森·金說：“通常實驗室制造的細(xì)胞是用2D方式培育出來的，但現(xiàn)在已經(jīng)3D打印出一些類型的細(xì)胞。不過，迄今為止，人體干細(xì)胞文化一直都比較敏感，還不能這么操作?！?/p>

“我們希望也相信這一科學(xué)發(fā)展對不用動物的可靠藥物測試會有極大的價值和長遠(yuǎn)意義，在更長遠(yuǎn)的未來，還能應(yīng)移植需求提供器官，不再需要器官捐獻(xiàn)，也不會產(chǎn)生免疫抑制和潛在的器官排斥問題?！?/p>