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2014年5月28日訊 最近來自哈佛大學(xué)懷斯生物工程研究中心的研究人員公布了他們最新研究成果，這一成果有望取代目前在藥物研發(fā)中廣泛使用的動(dòng)物實(shí)驗(yàn)方法。研究人員成功將骨髓細(xì)胞植入芯片用于模擬真實(shí)組織環(huán)境進(jìn)行藥物研究。研究人員希望利用這種芯片來研究放射引起的骨髓細(xì)胞壞死。

在一次FDA支持的研究中，研究人員利用這種芯片測(cè)試了一種能夠保護(hù)骨髓細(xì)胞免受射線傷害的藥物，結(jié)果顯示芯片上的細(xì)胞保持完整。這一結(jié)果被發(fā)表在五月4日的Nature Methods上。目前哈佛的科學(xué)家正在建立肺部、心臟以及腎臟等器官的生物芯片用于測(cè)試其在藥物研發(fā)中的作用。通過這種方法，動(dòng)物實(shí)驗(yàn)可能在未來退出藥物研發(fā)領(lǐng)域的舞臺(tái)。

詳細(xì)英文報(bào)道：

Scientists at Harvard's Wyss Institute for Biologically Inspired Engineering have unveiled their newest tool for drug testing, dubbed "bone marrow-on-a-chip," the first device of its kind that mimics the structure, functions and cellular make-up of bone marrow.

Bone marrow is made up of complex tissue and has, up until now, primarily been studied intact in living animals. Like the Wyss Institute's other organs-on-chipstechnology, the newly engineered bone marrow could provide scientists with a more accurate alternative to testing on animals. Wyss scientists hope the device could be used to help develop treatments to reverse cell death in bone marrow caused by radiation.

In an initial test with backing from the FDA, the engineered bone marrow imitated human marrow when it was exposed to radiation. When tested with a drug known to prevent radiation poisoning, the bone marrow-on-a-chip was unharmed. The findings are detailed in the May 4 issue of Nature Methods.

So far, Wyss scientists have built lung, heart, kidney and gut chips that reproduce important aspects of organ function using a technique that combines multiple types of cells from an organ on a microfluidic chip. But Wyss scientists needed to take a different approach to create engineered complex bone marrow that mimicked the real thing.

Investigators packed dried bone powder into an open, ring-shaped frame the size of a coin battery and implanted the mold under the skin on a mouse's back. After 8 weeks, the disk-shaped bone that had formed in the mold was surgically removed and examined with a CT scanner. The CT scan revealed a honeycomb-like structure that looked identical to natural trabecular bone, which holds bone marrow. In addition, the new bone marrow was saturated with red blood cells, resembling marrow from a living mouse.

After surgically removing the engineered bone from the mice, the researchers kept the bone marrow alive outside of the animals by placing it in a microfluidic device designed to steadily supply nutrients and remove waste, similar to what the tissue would experience in the body. The engineered marrow in the chip remained healthy for up to one week--long enough to use the device to test the toxicity and effectiveness of a new drug.