Thursday, May 21, 2009

China stem cell claims

FOR SCIENTISTS, doctors and patients, the power of stem cells holds much promise. Already, stem cells harvested from umbilical cord blood have successfully treated thousands of patients with leukaemia and other rare blood disorders, and researchers are testing the scope of stem cells to help us understand and possibly treat other conditions, with clinical trials at an early stage.

But Chinese company Beike Biotech has leap-frogged the validation procedures required for western medicine and is offering injections of cord blood stem cells to patients, including Irish children, who have conditions affecting the brain and nervous system.

They have already transplanted stem cells into more than 5,000 patients with conditions such as ataxia, autism, motor neuron disease, brain trauma, cerebral palsy, optic nerve problems and spinal cord injury.

“There are a lot of patients in countries around the world who could have a better quality of life and even extend their lives with the technology available but don’t have the chance because of politics, religion and bureaucracy,” runs the company’s mission statement.

“Beike’s goal is to help those people. Beike takes the most advanced biotechnological research in the world, specifically stem cell therapy, and applies it clinically at a rapid pace.”

Its rush to treat humans with experimental therapies has raised hackles among western medical professionals, but Beike’s standing in China is solid.

Set up in 2001 with funding from Beijing University, Hong Kong University of Science and Technology and Shenzhen City Hall, as well as the China State National Fund, the company operates in major hospitals and collaborates with some of the country’s top universities.

While Irish commentators vary in their scepticism about the effectiveness of the stem cell injections on offer, they unanimously stress the need for the procedures to be tested to international standards before the approach can be accepted.

Earlier this month, the Chinese government announced it was setting up a body to regulate the stem cell therapy sector, to stop unlicensed bodies setting up to cash in on what is a major growth market.

However, the regulations are still in an early form, and Beike is strongly supported by local government agencies, and is unlikely to fall foul of new rules.

Stories of patients travelling to China for costly stem cell therapies depress Dr Stephen Sullivan, visiting research fellow at Trinity College Dublin.

“It’s not because of the loss of money, but rather that stem cell research has yet to give patients and their loved ones a legitimate option,” he says.

“It also reminds me of the huge amount of misinformation being circulated on the internet and in the Irish media. This problem is growing, as people realise there is money to be made from people desperate to help their loved ones.”

Uninformed hype is fuelling the trend, he says. “When you say cord blood to people like me I start throwing my eyes up to heaven. Ultimately I see in the media that cord blood can do this and that and we should be getting cord blood banks in Ireland.

“But the medical and scientific consensus tells us that stem cells can be used to treat a very small number of conditions, [namely] diseases of the immune system and some rare blood conditions.”

Instead, he argues that stem cells are currently of interest because they can be encouraged in the lab to develop into more specialised cell types, thereby providing material to study disease and develop drugs.

And adult stem cells, such as the ones harvested from cord blood, are limited in the types of cell they can regenerate.

“There is zero evidence that cord blood can make [brain cells], for example,” says Sullivan.

He is also scathing of Beike’s lack of publications in international peer-reviewed journals. “If I had a treatment that could cure this kind of thing, as a responsible scientist or clinician, the first thing I would want to do is verify that such a procedure is safe and effective and then disseminate that information as quickly as possible,” he says.

Sullivan recently organised a conference in Dublin with the Irish Patients Association to discuss the problems of unproven stem cell therapies being offered as treatments. Beike was not invited to the meeting.

Irish pharmacist Peter Conry was also wary about using stem cells to treat a wide range of conditions, but then he visited Beike’s operations in China.

“I went there with the same sort of scepticism that anyone from here would have,” says Conry, who has worked in the pharmaceutical sector in China and now runs CelChem, a consultancy to link Irish and Asian companies.

Invited by Beike to visit its facilities, Conry was taken aback at the normality of the procedures at Beike’s hospital wards.

“When you see it as being a completely routine therapy, some of the big question marks become less relevant. They do this in teaching hospitals – it’s like being in Vincent’s or the Mater – so in case anything were to happen they have access to the whole facility. It’s not like you walk into someone’s office and get an injection and that’s it, and I know that happens in the dodgy end of things,” he says.

“ the same consultant who is handling neurological disorders on the third floor is the fellow looking after the patient coming over from Europe. When you see that you can’t have the same sort of scepticism.”

Conry spoke to several patients and their families, many of whom reported beneficial results, and some were on repeat visits for further transplants.

“From an outside point of view you could consider the changes as negligible, but for the people involved they saw that they were very valuable to them,” says Conry, who has advised Beike to engage in international clinical trials.

“I have spoken to people in China who had treatment and didn’t get anything other than a little bit more energy, so I know that it’s no miracle cure, but I believe it probably does work.”

But how can it work if adult stem cells cannot become brain or nerve cells? Beike claims that rather than stem cells engrafting themselves at a site of injury, they somehow marshal the body’s own repair system.

“The mechanism that the stem cells are working by is not engraftment, so the stem cells do not need to differentiate into other cells. They just provide nutrients and growth factors that allow them to revive dying cells and get the body to repair itself,” says Beike’s chief executive, Dr Sean Hu, who got his PhD from the University of Gothenburg in Sweden and worked in Canada before returning to China.

But peer-reviewed evidence of such activation by stem cells is scant, at least in journals published in English. However, Prof Frank Barry of the Regenerative Medicine Institute (Remedi) at NUI Galway comments that the idea may have some merit but it needs proof. PhD student Claire Kavanagh is currently researching it.

“We are doing lots of studies to try to understand the mode of action, such as delivering stem cells to infarcted hearts and then retrieving them later in order to see what they are doing. It does seem that they don’t differentiate but contribute signals and interact with the host in a way that does not require differentiation,” Barry says.

However, in the absence of concrete results for neurological conditions, word of Beike is spreading through patient testimonials on the internet, which is a problem, says Barry.

“There has been a lot of talk and promise about stem cells in the press and I think there is a huge placebo effect,” he notes. “And I think that as we do more work in trials we could see this being very significant, so you can’t rely on patient testimonials.”

That said, Barry realises that when it comes to loved ones and illness, scientific rationale may not always have the upper hand when opting for an unproven treatment. “If I were in the same situation there’s a chance I would do the same thing myself,” he says. “But in a situation like that you don’t think in a detached and logical way.”

And he joins the call for greater transparency. “There is no reason why they can’t publish in the international literature,” he says. “Chinese scientists are highly regarded throughout the world.” He says there’s no question about the quality of the research, but he would be concerned about the regulation of the clinics.

According to Beike, it is starting the process of trials. “We have a very professional clinical trial on diabetic foot coming up in India and we are sponsoring US physicians to do blinded studies to evaluate patients coming to China,” says Hu. “But a lot of patients don’t want to wait for this.”

Stem cells explained 

Stem cells have the capacity to divide and generate other cell types. 

There are three main kinds: embryonic, adult and induced. 

Embyronic stem cells are the most powerful and the most ethically controversial. They can be coaxed in the lab to regenerate over 200 different cell types. 

Adult stem cells are found in developed tissues and appear to have less capacity to regenerate a range of cell types, but can generally develop into cells of the tissue they are derived from. 

Published clinical data shows that adult cells from bone marrow and cord blood can treat blood cancers such as childhood leukaemia and other immune disorders. Trials using a patient’s own adult stem cells to help restore heart tissue after a heart attack show promise. 

Recent results indicate that cord blood-derived stem cells could help in treating a rare kidney disorder and juvenile diabetes. 

A new type of stem cell has been developed recently. Japanese researchers have published details of how they used viruses to “reboot” normal cells and turn them into pluripotent stem cells, which can regenerate many cell types. 

Source: The Irish Times 19 May 2009

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