The first stem cell factory

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Off-the-shelf stem cell treatments are finally here

Source : The Scientist February, 2016

The first stem cell factory begins

Grab a bag of stem cells

The launch of the first scientifically approved, mass-produced stem cells is the start of a new age of medicine, says Andy Coghlan. AFTER decades of hope, hype and disappointment, say hello to the world셲 first fully approved, mass-produced stem cell product.
Bags of Temcell are packed with 72 million living human cells, and will be launched in Japan later this month as a treatment for people whose organ transplants have turned against them.
Until now, stem cell therapy has mainly been used in unregulated private clinics or as an experimental treatment in clinical trials (see 쏷he dangerous allure of stem cells, below).
A handful of treatments have been approved, but these involve injecting someone with stem cells generated from their own cells a process that can take weeks and doesn셳 always work. The stem cells in Temcell, by contrast, come from healthy donors and can be multiplied to produce billions of standardised cells.
Developed by a company called Mesoblast in Melbourne, Australia, Temcell will be sold in Japan by JCR Pharmaceuticals. Formerly known as Prochymal, Temcell won approval in Canada and New Zealand, but was never commercially launched in either country.
Mesoblast is now carrying out the extra trials that are needed if Temcell is to be approved by US regulators next year.

A new wave

The launch is a milestone, because it propels stem cell therapy into the mainstream pharmaceutical industry. Stem cells from a donor can be cheaply manufactured in large batches, and supplied off the shelf using a business model much more like that for typical drugs, says Natalie Mount of the UK Cell and Gene Therapy Catapult, which helps guide stem cell trials.
Stem cells, the cellular putty from which all tissues in our bodies are produced, have long been touted as medicine셲 panacea because of their ability to repair damaged tissue or create new organs. 쏷hey are giving us the opportunity to do things never possible before, says Martin Evans of Cardiff University, UK, who won a Nobel prize in 2007 for work on embryonic stem cells.
In a few decades, stem cell therapy could be as normal as prescribing conventional drugs.
Whether it is eyes, hearts, lungs or spinal cords that need repairing, living cells could be available to do the job, coming pre-packed in syringes or bags, or taken from centralised stem cell banks.
Temcell is just the first of a wave of products that bring this dream closer to reality. Mesoblast has similar products in advanced clinical trials for treating more common conditions, including chronic heart failure, lower-back pain and rheumatoid arthritis.

“The cells act not like one drug, but like many, responding to signals from diseased tissue.”

And other companies are hot on its heels. 쏧 believe this is the first of many successes that will be seen over the next several years, says Stephen Huhn, chief medical officer of StemCells in Newark, California.
Mesoblast셲 products are made from mesenchymal stem cells extracted from a healthy person셲 bone marrow. As these cells mature, they form a range of tissues including bone, cartilage, fat and muscle. By extracting the cells at different stages of their development, or by exposing them to a cocktail of growth factors, you can turn them into specific cell types, such as those that specialize in the repair of damaged tissue. The other bonus is that they lack surface features marking them out as foreign, and so can be given to any patient without rejection.
Mesoblast says the stem cells in Temcell were selected for their ability to pacify white blood cells in transplanted tissue that would otherwise attack the cells of the recipient, a potentially fatal condition known as graft versus host disease. “It works by modulating the immune response, blocking pathways involved in tissue destruction and the proliferation of highly aggressive [immune cells] from the transplant,” says Donna Skerrett, chief medical officer at Mesoblast.
“This allows the patient to heal.”
In essence, the cells act not as one therapy, as a drug would, but as many acting together in response to biological distress signals from diseased tissue, says Silviu Itescu, Mesoblast셲 chief executive officer. For example, the cells Mesoblast has developed to treat chronic heart failure were chosen because as well as repairing and rebuilding damaged tissue, they reduce inflammation that causes scarring of heart muscle.
The same principle applies in the cells for treating back pain caused by worn down cartilage in the discs between vertebrae.
Evans expects stem cell products to come into their own within two generations.
This could see large pharmaceutical firms taking over from biotech companies as the main developers, says Michael West of BioTime, a stem cell company in Alameda, California.
Mesoblast셲 competitors agree that the launch of Temcell at last paves the way for therapies that have promised much but delivered little so far. 쏧t셲 an important first step, says Robert Lanza, chief medical officer of Ocata Therapeutics in Marlborough, Massachusetts, which is developing cell-based therapies to treat a cause of blindness. 쏷he launch of a mass-produced stem cell product is a huge achievement, but this particular one is just the tip of the iceberg. 뼚 See More : The Scientist Magazine 2016

THE DANGEROUS ALLURE OF STEM CELLS

Mass-produced, regulated stem cells are finally coming to market (see main story), but clinics have been using the cachet of stem cells for years to attract people to treatments that have no proof of benefit. 쏷hey make extremely powerful claims, so patients need to think about what the 쁱ed flag warning signs might be, says Leigh Turner of the University of Minnesota in Minneapolis, who studies the growth of unregulated clinics. 쏰ne is if a company claims a single stem cell therapy treats 20 or 30 diseases.
Some unregulated treatments have proven fatal, or caused severe injury. In 2013, Zannos Grekos, a cardiologist offering stem cell treatments through a company called Regenocyte, lost his licence after two of his patients died following reinjection of bone marrow tissue.
In Portugal in 2014, a woman treated for a spinal injury with an implant of nasal cells had to have a subsequent painful growth of nasal tissue removed surgically.
Turner estimates that there are between 100 and 200 unregulated clinics in the US. The Food and Drug Administration has issued warning letters to some clinics and the FBI has made arrests in at least one case. Things could soon get tougher.
Sarah Peddicord, a spokeswoman for the FDA, says it is revising its guidance to companies developing products based on human cells and tissues, and will be holding a public consultation on the proposed changes in April. If the changes go through, it will mean the FDA will classify the stem cells used in most clinics as drugs, and they will need to go through a rigorous approval process before they can be used in people.

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