日本埼玉医科大学细菌学教授三谷幸之介为首的科研小组日前开发了有效操作胚胎干细胞(ES细胞)基因的技术，该成果被刊登在8月25日发行的美国《国家科学院院刊》（PNAS）上。
胚胎干细胞是一种可成长为任何人体器官组织的“万能细胞”。
据日本共同社报道，该科研小组称，人类ES细胞基因操作在技术上一直存在困难。据悉，若使用新开发的技术方法，科研人员可将疾病的基因植入ES细胞，从而为制成再现症状的细胞提供方便，可能将加快有效治疗药物的研究。
科研小组使用了三谷教授开发的低毒性改良型病毒媒介作为将基因植入细胞的携带媒介。实际实验中将基因植入人类ES细胞后，目标位置的基因植入率为45%左右，比以往的1%有大幅提高。据悉，病毒原本携带的基因已事先被除去，因此也不存在安全性的问题。
据三谷教授称，该技术也将有助于新型万能细胞“iPS细胞”的研究。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS published August 25, 2008, doi:10.1073/pnas.0806136105
Heparin promotes the growth of human embryonic stem cells in a defined serum-free medium
Miho K. Furue*,?,?, Jie Na?, Jamie P. Jackson?, Tetsuji Okamoto§, Mark Jones?, Duncan Baker?, Ryu-Ichiro Hata‖, Harry D. Moore?, J. Denry Sato**, and Peter W. Andrews
A major limitation in developing applications for the use of human embryonic stem cells (HESCs) is our lack of knowledge of their responses to specific cues that control self-renewal, differentiation, and lineage selection. HESCs are most commonly maintained on inactivated mouse embryonic fibroblast feeders in medium supplemented with FCS, or proprietary replacements such as knockout serum-replacement together with FGF-2. These undefined culture conditions hamper analysis of the mechanisms that control HESC behavior. We have now developed a defined serum-free medium, hESF9, for the culture of HESCs on a type I-collagen substrate without feeders. In contrast to other reported media for the culture of HESCs, this medium has a lower osmolarity (292 mosmol/liter), l-ascorbic acid-2-phosphate (0.1 μg/ml), and heparin. Insulin, transferrin, albumin conjugated with oleic acid, and FGF-2 (10 ng/ml) were the only protein components. Further, we found that HESCs would proliferate in the absence of exogenous FGF-2 if heparin was also present. However, their growth was enhanced by the addition of FGF-2 up to 10 ng/ml although higher concentrations were deleterious in the presence of heparin.
