Potential For Improved Bone Marrow Transplants Following Stem Cell Discovery

decloud2009

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! L8 P6 \9 ]. d3 ?This news comes from website:  http://www.medicalnewstoday.com/articles/213054.php
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; [  p* s6 o4 y( \& y% ]! Q说明：由干细胞之家新闻小组成员decloud2009翻译（转帖请注明）。个人翻译，理解不准确的语句还望大家积极指出。8 R1 o9 e" `, J) K/ G2 p

# r; f# U! d  P$ CPotential For Improved Bone Marrow Transplants Following Stem Cell Discovery
+ J* S6 |! G+ v! l) [Researchers at the University of California, Santa Cruz, have identified a key molecule for establishing blood stem cells in their niche within the bone marrow. The findings, reported in the January issue of Cell Stem Cell, may lead to improvements in the safety and efficiency of bone marrow transplants.
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% X( ~5 s" U, i6 w5 K# [  O: sBone marrow transplants are a type of stem cell therapy used to treat cancers such as lymphoma and leukemia and other blood-related diseases. In a bone marrow transplant, the "active ingredients" are hematopoietic stem cells, which live in the bone marrow and give rise to all the different kinds of mature blood cells. The new study shows that hematopoietic stem cells use a molecule called Robo4 to anchor themselves in the bone marrow. . G& _+ e1 q! @: y% [( H
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"Robo4 is a rare molecule that is found only in hematopoietic stem cells and in the endothelial cells of blood vessels," said Camilla Forsberg, an assistant professor of biomolecular engineering in the Baskin School of Engineering at UC Santa Cruz. After earlier work in her lab showed that Robo4 is specific for hematopoietic stem cells, Forsberg set out to discover how it functions.
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' U5 {$ n& e& R! G2 {The discovery that the cells need Robo4 to stay in the bone marrow has potential therapeutic implications. An increasingly common alternative to traditional bone marrow transplants (which require anesthesia for the bone marrow extraction) involves harvesting hematopoietic stem cells from the blood. Repeated injections of drugs are needed to get the stem cells to leave the bone marrow and enter the bloodstream so that they can be collected with a blood draw. A drug that blocks Robo4 could be a safer and more effective way to do this, Forsberg said.
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"If we can get specific and efficient inhibition of Robo4, we might be able to mobilize the hematopoietic stem cells to the blood more efficiently," she said. "We're already working on that in the second phase of the project." & E% g( R/ p- p. z# j
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Robo4 acts as an adhesion molecule, interacting with other components of the bone marrow to bind the stem cells into their proper niche. Forsberg's lab is trying to find out what molecules bind to Robo4, which could lead to a better understanding of that niche. While other types of stem cells are routinely grown in petri dishes, hematopoietic stem cells are very difficult to grow in the lab. They seem to require the bone marrow environment to function properly, and Forsberg's research might enable researchers to recreate that environment in a petri dish. 1 t, K2 u) t: X  C0 U! A3 }4 [
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$ E# T0 B0 a. p8 n1 I* cOther molecules besides Robo4 are also known to be involved in guiding the localization of hematopoietic stem cells in the bone marrow. Forsberg's results indicate that one of these, called Cxcr4, acts together with Robo4 to retain hematopoietic stem cells in the bone marrow. But the two molecules appear to act through different molecular mechanisms. Inhibition of both molecules may be the best way to achieve efficient mobilization of hematopoietic stem cells, Forsberg said. - w3 E9 T0 \, b/ a1 X
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海洋注：3楼原文 感谢小鲁鲁 提供

decloud2009

加利福尼亚大学, Santa Cruz, 鉴定出可以在骨髓的微环境中建立造血干细胞的关键分子.5 _1 b. V! `7 H% K1 U* X
这项发现, 发表在Cell Stem Cell. 可能促进骨髓移植的安全性和有效性的改进。
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骨髓移植是被用来治疗淋巴癌，白血病和其他血液相关性疾病的一种干细胞治疗。 在骨髓移植中，活性成分是造血干细胞， 此类细胞存在骨髓中，可以产生所有种类的成熟血液细胞。这项新研究表明造血干细胞在骨髓中的定位需要一种叫做Robo4的分子。: O3 Z7 N( ~0 |: _" B" J8 b& j6 q# }
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“Robo4 是一种罕见的分子，目前只在造血干细胞和血管的内皮细胞中被发现。”Camilla Forsberg （an assistant professor of biomolecular engineering in the Baskin School of Engineering at UC Santa Cruz）说。 她在早期的实验工作中发现Robo4对造血干细胞来有特殊的作用，然后她开始研究其作用机制。
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这些细胞需要Robo3 才能存在骨髓中的研究发现具有潜在治疗意义。新的骨髓移植方法（与以前直接从骨髓中取细胞相比）需要从血液中获得大量的造血干细胞， 需要重复注射药物促进干细胞从骨髓中释放进入到血液中，然后我们从血液中收集这些干细胞。; [7 a, {- @" ]. w. Z! z6 h
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一个可以阻断Robo4 的药物可能会更安全、更有效的来获得这些细胞。Forsberg说：“如果我们可以获得特异并有效的Robo4阻断剂，我们就有更有效的动员造血干细胞从骨髓释放到血液中。我们已经进行到了第二个阶段了。”; N# [( b% w' _/ i4 [8 g% l

, D3 ?; F) [8 f+ kRobo4 充当黏附分子的角色，与骨髓中其他成分相互作用来使干细胞结合在合适的微环境中。Forsberg的实验室正试图找出与Robo4结合的分子，这个分子可能有助于我们更好的理解这个微环境。 但是，在培养皿中培养造血干细胞是一件很困难的事情。它们需要一个合适的骨髓环境来生长。Forsberg的研究有可能让研究者在培养皿中创造一个合适的造血干细胞生长的环境。. |) W) t) m+ N6 Y) v6 n
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其他的分子除了Robo4也与造血干细胞在骨髓中的定位有关。 Forsberg的研究结果指出其中一个分子Cxcr4， 和Robo4 一起，使造血干细胞阻留在骨髓中。 但是这两种分子的分子作用机制完全不同。7 U, T' C- ~# r8 ]9 j
同时抑制两种分子可能是获得造血干细胞有效动员的最好办法。Forsberg声称。8 x; u4 y  t$ V* B& l

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小鲁鲁

小弟附上原文，欢迎下载学习。
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