Blood-forming stem cells' growth identified in first breakthrough from new institute

January 25, 2012



DALLAS - Jan. 25, 2012 - Scientists with the new Children's Research Institute at UT Southwestern Medical Center have identified the environment in which blood-forming stem cells survive and thrive within the body, an important step toward increasing the safety and effectiveness of bone-marrow transplantation.

Institute investigators led by Dr. Sean Morrison asked which cells are responsible for the microenvironment that nurtures haematopoietic stem cells, which produce billions of new blood cells every day. The answer: endothelial and perivascular cells, which line blood vessels.

"Although scientists have searched for decades to identify the stem cell home, this is the first study to reveal the cells that are functionally responsible for the maintenance of blood-forming stem cells in the body," said Dr. Morrison, director of the new institute and senior author of the study available Jan. 26 in Nature. "This discovery will lead to the identification of the mechanisms by which cells promote stem cell maintenance and expansion."

Scientists already have determined how to make large quantities of stem cells and how to change these cells into those of the nervous system, skin and other tissues. But they have been stymied by similar efforts to make blood-forming stem cells. A key obstacle has been the lack of understanding about the microenvironment, or niche, in which blood-forming stem cells reside in the body.

In the first breakthrough from the Children's Research Institute, Dr. Morrison's laboratory addressed this issue by systematically determining which cells are the sources of stem cell factor, a protein required for the maintenance of blood-forming stem cells. His team swapped out the mouse gene responsible for stem cell factor with a gene from jellyfish that encodes green fluorescent protein. The cells that glowed green were endothelial and perivascular cells, revealing them as the creators of the niche that nurtures healthy blood-forming stem cells.

Additional lab work showed that blood-forming stem cells become depleted if stem cell factor is eliminated from either endothelial or perivascular cells. Loss of stem cell factor from both of these sources caused stem cells to virtually disappear.

The research has implications for bone marrow and umbilical cord blood transplants, Dr. Morrison said. If scientists can identify the remaining signals by which perivascular cells promote the expansion of blood-forming stem cells, then they may be able to replicate these signals in the laboratory. Doing so will make it possible to expand blood-forming stem cells prior to transplantation into patients, thereby increasing the safety and effectiveness of this widely used clinical procedure.

Dr. Morrison's paper is the first to emerge from the Children's Research Institute at UT Southwestern, a pioneering venture that combines the medical center's research prowess with the world-class clinical expertise of Children's Medical Center Dallas. Under Dr. Morrison's leadership, the institute is focusing on research at the interface of stem cell biology, cancer, and metabolism that has the potential to reveal new strategies for treating disease.
-end-
The institute currently has more than 30 scientists and will eventually include 150 scientists in 15 laboratories led by UT Southwestern faculty members. Dr. Morrison's lab focuses on adult stem cell biology and cancers of the blood, nervous system and skin.

The Nature paper's first author is Dr. Lei Ding, postdoctoral research fellow at the Children's Research Institute and the Howard Hughes Medical Institute. Scientists from the University of Michigan and Cold Spring Harbor Laboratory also contributed to the study, which was supported by the HHMI and the National Heart, Lung and Blood Institute.

This news release is available on our World Wide Web home page at www.utsouthwestern.edu/home/news/index.html

To automatically receive news releases from UT Southwestern via email, subscribe at www.utsouthwestern.edu/receivenews

UT Southwestern Medical Center


UT Southwestern integrates pioneering biomedical research with exceptional clinical care and education. Its faculty has many distinguished members, including five who have been awarded Nobel Prizes since 1985. Numbering more than 2,600, the faculty is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments.

Children's Medical Center Dallas

Children's Medical Center is a private, not-for-profit pediatric health-care system, the fifth-largest in the country with 559 licensed beds, two full-service campuses and 10 outpatient sites. Children's was the state's first pediatric hospital to achieve Level 1 Trauma status and is the only pediatric teaching facility in North Texas, affiliated with UT Southwestern. For information, please visit www.childrens.com.

UT Southwestern Medical Center

Related Stem Cells Articles from Brightsurf:

SUTD researchers create heart cells from stem cells using 3D printing
SUTD researchers 3D printed a micro-scaled physical device to demonstrate a new level of control in the directed differentiation of stem cells, enhancing the production of cardiomyocytes.

More selective elimination of leukemia stem cells and blood stem cells
Hematopoietic stem cells from a healthy donor can help patients suffering from acute leukemia.

Computer simulations visualize how DNA is recognized to convert cells into stem cells
Researchers of the Hubrecht Institute (KNAW - The Netherlands) and the Max Planck Institute in Münster (Germany) have revealed how an essential protein helps to activate genomic DNA during the conversion of regular adult human cells into stem cells.

First events in stem cells becoming specialized cells needed for organ development
Cell biologists at the University of Toronto shed light on the very first step stem cells go through to turn into the specialized cells that make up organs.

Surprising research result: All immature cells can develop into stem cells
New sensational study conducted at the University of Copenhagen disproves traditional knowledge of stem cell development.

The development of brain stem cells into new nerve cells and why this can lead to cancer
Stem cells are true Jacks-of-all-trades of our bodies, as they can turn into the many different cell types of all organs.

Healthy blood stem cells have as many DNA mutations as leukemic cells
Researchers from the Princess Máxima Center for Pediatric Oncology have shown that the number of mutations in healthy and leukemic blood stem cells does not differ.

New method grows brain cells from stem cells quickly and efficiently
Researchers at Lund University in Sweden have developed a faster method to generate functional brain cells, called astrocytes, from embryonic stem cells.

NUS researchers confine mature cells to turn them into stem cells
Recent research led by Professor G.V. Shivashankar of the Mechanobiology Institute at the National University of Singapore and the FIRC Institute of Molecular Oncology in Italy, has revealed that mature cells can be reprogrammed into re-deployable stem cells without direct genetic modification -- by confining them to a defined geometric space for an extended period of time.

Researchers develop a new method for turning skin cells into pluripotent stem cells
Researchers at the University of Helsinki, Finland, and Karolinska Institutet, Sweden, have for the first time succeeded in converting human skin cells into pluripotent stem cells by activating the cell's own genes.

Read More: Stem Cells News and Stem Cells Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.