Tuesday, June 5, 2012

"It will be years before there are treatments made from stem cells on the shelves."

I'm out of town. Just a quick post with a link to quite an informative article on stem cell clinical trials development.  Here is the link to the main article : Stem cell scientists take hope from first human trials but see long road ahead


Even though the stem cell research has come a long way from the first discovery of embryonic cells in 1989 to clinical trials today, we might need to wait several more years before we can find on-the-shelf treatment for a lot of currently untreatable diseases like Parkinson's disease, Type 1 diabetes, Chronic liver disease and heart diseases and ofcourse Stargardt's disease.


A lot still depends on the outcome of the  world's first human trial using RPE (retinal pigment epithelium) cells from stem cells derived from humon embryos. In phase one trial earlier this year, some Stargardt's and Age-related macular degeneration patients were injected with a tiny amount of RPE cells (50,000). Patients have reported small improvement that have nonetheless significantly changed their lives.  The chief scientific officer at Advanced Cell Technology Inc., Dr Robert Lanza thinks that "It is very hopeful if we are seeing this with a small number of cells at the very advanced stage, imagine what we could do with those young children who are going blind at the age of six to 10, sometimes."


Although the patients treated with the stem cell trial are taking precautionary drugs, they might not need to take immuno-suppressant drugs for lifelong unlike most transplant patients. Eyes are "immune privilleged" and "can better tolerate a graft of human tissue without the immune system mounting an all-out attack and causing rejection" says Prof Pete Coffey, of the Institute of Ophthalmology at University College London,

Ethical Problem and Funding issues

From the start, there has been strong political opposition on the use of embryonic stem cells. The destruction of an embryo is viewed as tantamount to murder of an early staged human life .And it violates the belief system that life begins when a sperm cell fertilizes an egg cell to form a single cell.  The opposition in Europe led to European court's ban on stem-cell patents in Europe in October last year. This means that any future clinical trials or research in stem cell therapy would not be protected in Europe. As a result, the biotech companies supporting stem cell research are facing serious funding challenges from investors. There is still strong views from political parties to stop European funding.
  
IPS cells vs Embryo cells

Despite the more recent advance regarding induced pluripotent stem cells (IPS), which are cells from skin or other parts of the patient's own body, IPS cells still remain an unworkable, enormously expensive and unrealistic solution in comparison to embryonic stem cells as of today.

"The embryonic cells are affordable and "you can treat many people with one batch of cells. That makes it somehow conceivable that it could be economically viable for the healthcare system.". ACT's Lanza says they have enough RPE to treat everybody on the planet.""

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Embryonic/IPS cells vs Mice cells

Scientists believe that a great deal of research is still required because both embryonic and IPS cells are not the same as the true embroyinc cells from the mice.
"Mice embryonic stem cells, which have been used in so much early stage research, appear to be slower than human embryonic cells to divide and differentiate. Basically, the human cells taken from a blastocyst (a five- or six-day embryo) have already moved on to the next stage, where equivalent mouse cells have not. That makes it hard to produce standardised cells that will all, for instance, make exactly the same nerve cells. There have been some partial successes but, says Smith, "we don't have a human cell either from an embryo or re-programmed that is held at this ground state." Taking cells at an earlier moment in the blastocyst development won't work, he says. "It is not the starting point that is important. The biology is subtly different between rodents and primates.""

Outcome of First safety trials in human

There is a lot of hope in the scientific community on the current stem cell clinical trials to cure Stargardt's Disease. Positive outcome will also mean that human embryonic stem cell trials for other diseases like Parkinson's and diabetes could also begin in next 4-5 years.No damage has been so far reported by Advanced Cell Technology for those who were treated with RPE cells.



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