Navigation Links
Researchers decipher blood stem cell attachment, communication
Date:3/25/2009

Researchers at the National Institutes of Health have deciphered a key sequence of events governing whether the stem cells that produce red and white blood cells remain anchored to the bone marrow, or migrate into the circulatory system.

An understanding of the factors that govern migration of blood stem cells might lead to improved treatment of leukemia, a cancer that affects circulating white blood cells. The findings also have implications for culturing infection-fighting immune cells outside the body, where they could be temporarily held in storage during chemotherapy and other treatments which suppress the immune system. Moreover, the findings could contribute to a strategy for growing large quantities of red blood cells in laboratory dishes outside the body, to reduce the need for blood donations.

Previously, researchers thought that the cellular environment in which the stem cells reside produced the chemical signals that determined whether the cells would be stationary or freefloating. The current study provides evidence that the stem cells produce chemical signals of their own that may, in turn, influence the chemical signals they receive from their environment.

"This important discovery will advance our understanding of how blood cells and immune cells are generated," said Duane Alexander, M.D., director of the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD).

The findings were published on line in Nature Cell Biology. The study was conducted in the laboratory of Jennifer Lippincott-Schwartz, Chief of the NICHD Section on Organelle Biology. The study's first author was Jennifer Gillette, also of the Section on Organelle Biology. Other authors were Andre Larochelle and Cynthia E. Dunbar of the Hematology Branch of NIH's National Heart, Lung, and Blood Institute.

Dr. Gillette explained that hematopoetic progenitor stem cellsthe cells which give rise to red blood cells and immune cellstravel between the bloodstream and the bone marrow. Within the bone marrow, they anchor themselves in place by attaching to bone marrow cells called osteoblasts.

Other studies have shown that osteoblasts secrete a substance that acts as a chemical signal that regulates the attachment of the stem cells. Large amounts of the chemical, which is known as SDF-1 (stromal cell derived factor-1), cause the stem cells to leave the bone marrow and enter the bloodstream. A small, continuous pulse of SDF-1, however, attracts the stem cells and results in their attachment to the osteoblasts.

In laboratory cultures, Dr. Gillette and her coworkers incubated unattached stem cells with osteoblasts. As the stem cells approached the osteoblasts, they developed long, tentacle-like projections, called uropods. The uropods attached to the surface of the osteoblasts. Then, a small portion of a uropod was absorbed inside an osteoblast. The uropod material was eventually sealed inside an endosomea tiny balloonlike structure within the cell. After the osteoblasts absorbed the uropod material, they began producing SDF-1.

Dr. Gillette noted it appeared to be the stem cell material that stimulated the osteoblast to produce SDF-1, the substance that causes the stem cell to remain attached to the osteoblast or migrate into the blood.

"Our study indicates that stem cells may actually be able to manipulate the signals that they receive from their environment," Dr. Gillette said. "Stem cells seem to have a little more control than we thought."

Next, the researchers plan to study the influence of SDF-1 on leukemia cellsfree floating cancer cells that originate from stem cells, in hopes of learning how leukemia cells communicate with their cellular environment.

"One lead we hope to pursue is determining whether the cancer cells stimulate the cells in their environment to produce substances that help them grow in a similar manner," she said. "Perhaps we could disrupt these signals and inhibit the cancer cells."

Moreover, by learning more about the binding process itself, researchers may one day be able to duplicate the factors that stimulate stem cells to remain stationary and begin producing blood cells. The ability to culture blood in the laboratory could decrease the need for blood donations.


'/>"/>

Contact: Robert Bock
bockr@mail.nih.gov
301-496-5133
NIH/National Institute of Child Health and Human Development
Source:Eurekalert

Related medicine news :

1. Researchers studying hearing loss find auditory regions of the brain convert to the sense of touch
2. UIC researchers measure health effects of Chicagos waterways
3. Focus on treating malnutrition in cancer patients, researchers say
4. Researchers Suspect Genetic Link to COPD
5. Syracuse University researchers build a new surface material that resists biofilm growth
6. Researchers Use Gene to End High Blood Sugar in Mice
7. Penn researchers identify new protein important in breast cancer genes role in DNA repair
8. Fish health claims may cause more environmental harm than good: UBC-St. Michaels researchers
9. Researchers clone key sperm-binding proteins
10. Researchers find sustained improvement in health in Experience Corps tutors over 55
11. Researchers develop DNA patch for canine form of muscular dystrophy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... Oklahoma City, Oklahoma (PRWEB) , ... June 25, ... ... to helping both athletes and non-athletes recover from injury. Recently, he has implemented ... for the Oklahoma City area —Johnson is one of the first doctors to ...
(Date:6/25/2016)... ... 25, 2016 , ... Conventional wisdom preaches the benefits of moderation, whether it’s ... setting the bar too high can result in disappointment, perhaps even self-loathing. However, those ... goal. , Research from PsychTests.com reveals that behind the tendency to ...
(Date:6/24/2016)... ... June 24, 2016 , ... Those who have experienced traumatic ... many turn to unhealthy avenues, such as drug or alcohol abuse, as a coping ... released tools for healthy coping following a traumatic event. , Trauma sufferers tend to ...
(Date:6/24/2016)... , ... June 24, 2016 , ... Marcy was in a crisis. Her son James, ... out at his family verbally and physically. , “When something upset him, he couldn’t control ... use it. He would throw rocks at my other children and say he was going ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Global law ... magazine’s 2016 Legal Elite. The attorneys chosen by their peers for this recognition are ... , Seven Greenberg Traurig Shareholders received special honors as members of this year’s Legal ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... OAKLAND, N.J. , June 24, 2016 /PRNewswire/ ... in the design, development and manufacturing of collagen ... and regeneration announced today that Bill Messer ... Sales and Marketing to further leverage the growing ... surgery medical devices. Bill joins the ...
(Date:6/24/2016)... , June 24, 2016   Bay Area ... Network,s Dean Center for Tick Borne Illness ... and Rehabilitation, MIT Hacking Medicine, University of California, ... today announced the five finalists of Lyme ... disease.  More than 100 scientists, clinicians, researchers, entrepreneurs, ...
(Date:6/24/2016)... , June 24, 2016 ... the "Structural Electronics 2015-2025: Applications, Technologies, Forecasts" ... In-Mold Electronics, Smart Skin, Structural ... Structural electronics involves electronic and/or ... protective structures, replacing dumb structures such as vehicle ...
Breaking Medicine Technology: