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赤血球によく似た粒子が作製された。まだ初期段階だが，人工血液の開発や癌治療に役立つ可能性がある。赤血球は変形しながら臓器の微小な孔や狭い血管を通過するが，やがて硬くなり循環から除去される。人工の赤血球を作る従来の研究では，粒子の十分な柔軟性が得られなかった。今回作製された粒子は，酸素の運搬などの機能についてはまだ検討されていないが，サイズ，形状，柔軟性が赤血球に似ている点で画期的だという。また，抗癌剤をこの粒子に搭載して体内の循環に長く留まらせるといったように，癌治療への応用も考えられる。（吉田素子）
UNC Researchers Inch Closer to Unlocking Potential of Synthetic Blood
A team of scientists has created particles that closely mirror some of the key properties of red blood cells, potentially helping pave the way for the development of synthetic blood.
The new discovery – outlined in a study appearing in the online Early Edition of the Proceedings of the National Academy of Sciences during the week of Jan. 10, 2011 – also could lead to more effective treatments for life threatening medical conditions such as cancer.
University of North Carolina at Chapel Hill researchers used technology known as PRINT (Particle Replication in Non-wetting Templates) to produce very soft hydrogel particles that mimic the size, shape and flexibility of red blood cells, allowing the particles to circulate in the body for extended periods of time.
Tests of the particles’ ability to perform functions such as transporting oxygen or carrying therapeutic drugs have not been conducted, and they do not remain in the cardiovascular system as long as real red blood cells.
However, the researchers believe the findings – especially regarding flexibility – are significant because red blood cells naturally deform in order to pass through microscopic pores in organs and narrow blood vessels. Over their 120-day lifespan, real cells gradually become stiffer and eventually are filtered out of circulation when they can no longer deform enough to pass through pores in the spleen. To date, attempts to create effective red blood cell mimics have been limited because the particles tend to be quickly filtered out of circulation due to their inflexibility.
［単語和訳］
UNC：ノースカロライナ大学の略 Researchers：研究者 Inch Closer to： ～に少し近づく Unlocking：～を開くこと Synthetic：人工の
particles：粒子 properties：特性 red blood cells：赤血球 potentially：可能性をもって pave the way for：～の下地を作る
online Early Edition：オンライン速報版 Proceedings of the National Academy of Sciences：米国科学アカデミー紀要（きよう）（雑誌名） lead to：～につながる life threatening：生命にかかわる medical conditions：疾患（病状） cancer：癌
Replication：複製 Non-wetting：非湿潤性 Templates：テンプレート hydrogel：ヒドロゲル mimic：～を再現する flexibility：柔軟性 circulate：循環する for extended periods of time：長時間
therapeutic drugs：治療薬剤 cardiovascular system：心血管系 as long as：～であるならば
deform：変形する in order to：～するために pass through：～を通過する microscopic：微細な pores：孔 blood vessels：血管 120-day：120日間の lifespan：寿命 are filtered out of：～からろ過で除去される circulation：循環 spleen：脾臓 To date：今まで mimics：模倣したもの inflexibility：柔軟性のなさ
