Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New primate stem cell

01.02.2002


All the replacement tissues with none of the ethical dilemmas?
© Science


Dividing, unfertilised eggs could offer new therapeutic option

US researchers have cloned stem cells from the unfertilized eggs of primates - our closest animal relatives. The achievement suggests it may be possible to grow cells that can give rise to any tissue in the human body without cloning and destroying human embryos.

Some researchers in the field doubt whether the technique will work in humans. And opponents of therapeutic cloning do not believe the new cells solve any of the ethical dilemmas of producing embryonic stem (ES) cells.



Michael West at Advanced Cell Technology (ACT) in Worcester, Massachusetts, and colleagues tricked macaque egg cells into dividing without having first been fertilized. They used a chemical cocktail similar to the one sperm use to make eggs divide.

The dodge - called parthenogenesis - is done routinely with laboratory mice but ACT is the first to pull it off in primates. The resulting cells, called parthenotes, are clones of their mother. Experiments in mice suggest that parthenote embryos die before developing normally.

Stem-cell researchers’ ultimate goal is to replace any malfunctioning body tissue, such as diabetics faulty pancreas cells or the degrading nerve sheaths in multiple sclerosis patients. One of their greatest challenges is to get stem cells to commit to becoming a particular cell type - a process called differentiation.

Primate parthenotes are, if anything, easier to grow into different tissue types than ES cells, says West: "It’s all there: skin with hair follicles, developing eye tissue." His team even managed to create nerve cells that could produce dopamine. Human equivalents could replace the brain cells destroyed by Parkinson’s disease.

Limited application

"It’s an interesting step," says Harry Griffin, of the Roslin Institute in Scotland, birthplace of Dolly the cloned sheep. But he doubts whether parthenotes will provide an alternative to therapeutic cloning - itself a long way from becoming a medical reality.

Azim Surani, a developmental biologist at Cambridge University in England agrees: Parthenote cells lack the influence of male chromosomes, which have subtle effects on cell growth and development. Although West’s cells grow in the test tube, "we cannot assume that they will behave normally when implanted in an organism," he says.

Plus stem cell therapy aims to produce cells from the patient’s own tissue that exactly match their bodies cells. And the majority of diseases that stem cells would treat are age-related. Older women no longer produce egg cells from which to make parthenote stem cells, says Griffin.

West admits that parthenotes’ potential is not fully understood. But he feels that their ready availability could be a boon to stem-cell science. "Medical researchers need to have options," he says.

Still controversial

Unfortunately parthenotes don’t side-step all objections to creating human embryos as a source of stem cells. "The ethical issue is not solved by this," says Bill Saunders, spokesman for the Washington DC-based Family Research Council, which opposes the use of embryos in research.

Parthenotes, although unfertilized, do form embryos, so they are living, Saunders argues. "Single-celled organisms that have the capacity to divide and grow are a member of the human species," he says.

References

  1. Cibelli, J. B. et al. Parthenogenetic Stem Cells in Nonhuman Primates. Science, 295, 465(2002).


TOM CLARKE | © Nature News Service

More articles from Life Sciences:

nachricht Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory

nachricht How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>