Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.


'Embryonic-like' stem cells not found

25 July 2013, 17:28

Washington - A US company that promoted its stem cell discovery in partnership with the Vatican has come under fresh scrutiny by independent scientists who said on Wednesday the cells do not exist.

Scientists at Stanford University said in the journal Stem Cell Reports they could not replicate NeoStem's findings of very small embryonic-like cells (VSELs) in the bone marrow of lab mice.

These cells have been touted by the New York-based company as an ethical alternative to stem cells requiring the destruction of human embryos, with the same regenerative ability to transform into other cell types in the body.

Earlier this year, NeoStem announced plans to launch the first human trials of the cells for bone growth.

"We tried as hard as we could to replicate the original published results using the methods described and were unable to detect these cells in either the bone marrow or the blood of laboratory mice," said lead author Irving Weissman, who directs Stanford's Institute for Stem Cell Biology and Regenerative Medicine.

Weissman's study is the first to evaluate the biological potency of the cells, and it found they could not transform into blood cells and contained very little DNA.

Instead, researchers found that what purported to be VSELs - about five micrometers in diameter - were either debris or dead cells.

"A true pluripotent cell would be able to differentiate into any tissue type," said Weissman. "But we couldn't confirm that cells of that size or phenotype could generate hematopoietic cells with any reliability."

In response, NeoStem chair and CEO Robin Smith said the company has studies in progress that will "confirm whether or not VSEL(s) have characteristics of a pluripotent stem cell."

"We acknowledge that there is controversy in the VSEL field but this is not unusual for most new scientific discoveries and theories [Darwin and evolution, Copernicus and earth orbiting the sun as examples]," Smith said in a statement e-mailed to AFP.

The cells were first described in 2006 by researchers working with lab mice at the University of Louisville in Kentucky.

Lead author of that first study to describe VSELs, Mariusz Ratajczak, told the journal Cell Stem Cell, in the edition coming out 1 August, that he was anxious about the pace.

"I'm a little bit scared because I know that NeoStem would like to go fast to the clinic," he was quoted as saying. "I still think we need to do more basic research."

NeoStem has about 20 patent applications that protect the method for isolating the cells.

The company along with other partner institutions have also received $4.5m in government research grants, including from the Department of Defence and the National Institutes of Health.

In 2010, it partnered with the Vatican on a charity to promote awareness of alternatives to embryonic stem cell research.

"Your own adult stem cells are the perfect ethical and moral alternative to stem cells derived from other donors or from embryonic stem cells," NeoStem says on its website.

According to Ihor Lemischka, professor of regenerative biology and director of the Black Family Stem Cell Institute at The Mount Sinai Medical Centre in New York, the money spent on VSEL research was a "waste of funding."

"My impression is that this has been a controversial issue since the VSEL cells were first described," said Lemischka, who was not involved with the research.

"It is good that the Weissman laboratory, one of the most prominent stem cell labs in the world, has addressed these issues," he told AFP.

"Optimistically, the issue could now be well on the way to being settled," said Lemischka.



Read News24’s Comments Policy

Comment on this story
Comments have been closed for this article.

Read more from our Users

Submitted by
Jayne Zack
I am in ODM to stay, Busia Depu...

Busia Deputy Governor Kizito Wangalwa told Deputy President William on the face that he was in the Orange Democratic Movement to stay. Read more...

Boda Boda operators in Bahati rai...

Motorbike Boda Boda operators from Bahati Sub county on Tuesday took to the streets of Nakuru’s CBD lamenting over what they term is harassment by patrol police officers in the area. Read more...

Submitted by
Gabriel Ngallah
Human Rights activist lives in fe...

The Human rights fraternity in Mombasa is currently living in fear after the home of one of the vocal human rights champion was invaded on Monday night. Read more...

Submitted by
kel wesh
Poisonous milk powder siezed by K...

The Kenya Revenue Authority has seized two containers with illegal milk powder which had been declared as gypsum board at Mombasa port. Read more...

Submitted by
William Korir
Be ready for protests, Raila warn...

Expect protests if meddling with Auditor General continues, Raila Odinga has said. Read more...

Submitted by
Kenya says will return to interna...

Kenya will return to international markets to borrow when it feels the time is right, National Treasury Cabinet Secretary Henry Rotich said on Tuesday. Read more...