Stem Cell Discovery Could Lead to Improved Bone Marrow Transplants
ScienceDaily (Jan. 6, 2011) — 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.
Bone 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.
"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.
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.
"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."
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.
Other 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.
Stephanie Smith-Berdan, a research specialist in Forsberg's lab, is first author of the new paper. Coauthors include UCSC researchers Andrew Nguyen, Deena Hassanein, Matthew Zimmer, Fernando Ugarte, and Lindsay Hinck, professor of molecular, cell and developmental biology; Dean Li of the University of Utah; and Jesus Ciriza and Marcos Garcia-Ojeida of UC Merced. This work was funded by UCSC and the California Institute for Regenerative Medicine. 生命科学研究快报文件类型:DOC/Microsoft Word- 文字版生命科学研究快报 2005年第1期(总第64期) (仅供内部参考) 目录 【科技发展动态:科技... 无血缘关系供受体移植迅猛增加的情况下,带来提高造血干细胞移植配型的成功率和精确度...www.library.sh.cn/...05/64.doc-2010-11-22-生命科学研究快报" 医药新知_39健康问答_39健康网以寻求不孕症原因,改进着床条件,提高人工助孕着床成功率. 据加拿大药物不良反应公报... 中国医学科学院赵春华教授领导的863课题组最近的研究发现,骨髓间充质干细胞 MSC ...ask.39.net/...tion/645046.html-2004-09-07-快照-医药新知_39健康问答_39健康网" 疾控媒体快讯文件类型:PDF/Adobe Acrobat- 文字版因此,莫西沙星的应用对提高呼吸道感 染的初始经验治疗的成功率有重要作用. http://... 尽管感光细胞移植研究为眼科治疗带来革命性突破,但科学家说,这类研究尚处于萌芽 阶段,...www.cdcp.org.cn/...0413415.pdf-2010-10-16-[标签:content2]
作者:admin@医学,生命科学 2011-01-08 00:42