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

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers watch quantum knots untie

After first reporting the existence of quantum knots, Aalto University & Amherst College researchers now report how the knots behave

A quantum gas can be tied into knots using magnetic fields. Our researchers were the first to produce these knots as part of a collaboration between Aalto...

Im Focus: A cavity leads to a strong interaction between light and matter

Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.

Quantum physics describes photons as light particles. Achieving an interaction between a single photon and a single atom is a huge challenge due to the tiny...

Im Focus: Solving the mystery of quantum light in thin layers

A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)

It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...

Im Focus: An ultrafast glimpse of the photochemistry of the atmosphere

Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.

The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...

Im Focus: Shaping nanoparticles for improved quantum information technology

Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.

Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

NEXUS 2020: Relationships Between Architecture and Mathematics

02.10.2019 | Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

 
Latest News

Composite metal foam outperforms aluminum for use in aircraft wings

23.10.2019 | Materials Sciences

Researchers watch quantum knots untie

23.10.2019 | Physics and Astronomy

A technology to transform 2D planes into 3D soft and flexible structures

23.10.2019 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>