New Stem Cell Screening Tool Takes Adult Stem Cell Research To New Level

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New Stem Cell Screening Tool Takes Adult Stem Cell Research To New

Level

http://medicalnewscenter.com/recent/science-daily-medical-news.shtml

Stem cell research is the next great leap in medicine. In the future,

new tissue grown in a laboratory could replace a failing heart, or

new cells take the place of damaged cells in the brain.

Rather than using stem cells from embryonic sources, which opens

difficult ethical and complicated scientific issues, scientists have

been looking to adult human stem cells, culled from a person's own

body. Adult stem cells are now being cultivated from various tissues

in the body -- from skin, bones and even wisdom teeth.

At the forefront in this research is a team of scientists from Tel

Aviv University and Scripps Research Institute in California. They

recently reported a breakthrough on a new classification system for

identifying pluripotent stem cells in human tissue. News about this

system recently appeared in the scientific journal Nature.

Pluripotent stem cells have the potential to differentiate into every

distinct cell type in the developed human body. They hold great

promise for use in drug development and the treatment of many

devastating disorders.

Avoiding Cultural and Religious Controversy

" There is a huge interest in scientists taking skin cells or other

body cells of a person, and then turning them into stem cells for

creating new neurons in the brain, " says Igor Ulitsky, a Ph.D.

student at Prof. Ron Shamir's lab in the Blavatnik School for

Computer Science, Tel Aviv University, who pioneered some of the

research techniques. " Using a person's own stem cells is both

ethically acceptable, and in some cases even better for regenerating

tissue than embryonic stem cells. "

Tel Aviv University research played a central role, creating new

bioinformatics algorithms to analyze the data and put together the

pieces of the puzzle. The result is, in effect, an encyclopaedia

describing different stem cell types and their characteristics.

Before this breakthrough, made possible by international

collaboration, scientists were baffled by how to distinguish

different stem cell types. " Our lab helped devise a method to

classify stem cells according to their machinery, " Ulitzky

explained. " Stem cells have small but significant differences between

them, and knowing the potential properties of each kind is valuable

for advancing this promising field of research. "

An Ethical and Scientific Test

With rapid advances in the field of stem cells -- including methods

to induce pluripotence in various cells, such as those that comprise

human skin -- the question of how to define pluripotence has become

increasingly critical. This is especially the case for human cell

lines, which for both ethical and scientific reasons cannot be

treated as those from other species.

" There has been no ethically acceptable equivalent test that could

prove pluripotency in human cell preparations, " said Franz-f

Mueller, M.D., an investigator at Scripps. " Many have been purported

to be multi- or pluripotent, but there has been no practical way to

define pluripotency in human cells. "

Using a collection of about 150 human stem cell samples, the

researchers created a database of global gene expression profiles and

discovered that all of the pluripotent stem cell lines showed a

remarkable similarity in the analysis, while other cell types were

more diverse.

The analysis by Shamir's lab revealed a protein-protein network

common to pluripotent cells, pointing to what may be one of the key

building blocks of the machinery that enables these transformative

cells to differentiate into multiple cell types. Next, the

researchers plan to investigate the regulation of this protein

network and how it might be used to advance the development of human

gene therapies.

This study was supported by several grants including the Edmond J.

Safra Bioinformatics Program and the and Beverly Sackler

Chair in Bioinformatics at Tel Aviv University.