Featured Research

from universities, journals, and other organizations

Stem Cells Get A Grip

Date:
December 15, 2006
Source:
American Society for Cell Biology
Summary:
At the American Society for Cell Biology's 2006 conference, scientists will describe how live cell imaging has revealed the very close relationship of hematopoietic stem cells and osteoblasts in the stem cell niche.

In real estate, it's location, location, location. In stem cells, it's niche, niche, niche.

Stems cells are regulated by "intrinsic factors" but it's also becoming increasingly clear that their "stemness" depends on the unique microenvironment called the stem cell niche.

No adult or somatic stem cells have a more complex niche life than hematopoietic stem cells, which give rise to all the different types of blood and immune cells. The bone marrow is their niche. It's a crowded neighborhood, teeming with different cell types such as fibroblasts, adipocytes, macrophages, and endothelial cells. Hematopoietic stem cells also share their bone marrow niche with osteoblasts, the body's bone-forming cells, which are derived from a different stem cell population called bone marrow stromal cells. The two stem cells lines probably have a common progenitor but for now scientists can only regard hematopoietic stem cells and osteoblasts as niche neighbors. But it's a very close relationship, as researchers in the National Institute of Child Health & Human Development laboratory of Jennifer Lippincott-Schwartz now reveal in great detail.

Earlier reports had established that osteoblasts are a crucial component of the hematopoietic stem cell niche and that physical contact with osteoblasts was vital for their survival. The Lippincott-Schwartz lab used live cell imaging techniques to see what happens when the two cell types are put together, directing their attention in particular at the point of cell-cell contact, and how it affects the cellular and molecular relationship of the two cell types.

The NIH researchers observed dynamic amoeboid motility toward the osteoblasts by both human CD34+ hematopoietic progenitor cells and KG1 cells, which are a hematopoietic subset of myeloid progenitors. The progenitor cells assumed a polarized morphology with a leading edge structure and a foot-like "special domain" projection from the cell's trailing edge called a uropod. It was through this foot that the hematopoietic stem cells took hold of the osteoblasts. The uropod contact point was enriched in the cholera toxin B subunit, a lipid raft molecule, as well as the stem cell marker CD133.

The researchers had seeded the outside of the progenitor cells with microscopic markers, quantum dot nanocrystals, and watched as the dots were taken into the cells and delivered specifically to the uropod domain at the point of contact. Interestingly, time-lapse microscopy detected transfer of the quantum dots from the progenitor cells to the osteoblastic cells, suggesting an intercellular transfer of cell-associated molecules. Immune cells are known to transfer cell-surface molecules during cell-cell interactions so a similar intercellular transfer between hematopoietic progenitors and osteoblasts could be of broad biological significance, the researchers say. Further studies will explore how these close neighbors pull together in the hematopoietic niche.


Story Source:

The above story is based on materials provided by American Society for Cell Biology. Note: Materials may be edited for content and length.


Cite This Page:

American Society for Cell Biology. "Stem Cells Get A Grip." ScienceDaily. ScienceDaily, 15 December 2006. <www.sciencedaily.com/releases/2006/12/061215091126.htm>.
American Society for Cell Biology. (2006, December 15). Stem Cells Get A Grip. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2006/12/061215091126.htm
American Society for Cell Biology. "Stem Cells Get A Grip." ScienceDaily. www.sciencedaily.com/releases/2006/12/061215091126.htm (accessed April 18, 2014).

Share This



More Health & Medicine News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) Video provided by AP
Powered by NewsLook.com
Is Apathy A Sign Of A Shrinking Brain?

Is Apathy A Sign Of A Shrinking Brain?

Newsy (Apr. 17, 2014) A recent study links apathetic feelings to a smaller brain. Researchers say the results indicate a need for apathy screening for at-risk seniors. Video provided by Newsy
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins