Anyone selling such therapies is promising things that science can’t yet offer.
Stem cells, photo Getty Images
If life was as simple as that of a flatworm, we could be cut in half, and in half again, and over the following days, our quartered parts would develop into four new people, thanks to the regenerative power of stem cells. Stem cells are ingenious things that divide, multiply and generate all the other cells in the body, transforming a piece of flatworm into a fully formed flatworm, allowing a newt to grow a new tail and a starfish a new arm.
Worms, starfish and newts are simple creatures, and excellent at regenerating. Humans are biologically complex, and even though we have stem cells we have poor regeneration skills – unless scientists can harness stem cells in a way that changes all that. There have been a number of remarkable breakthroughs in stem cell therapy in the past decade; scientists have discovered that adult stem cells may be just as effective as embryonic stem cells, which means we can avoid the ethical dilemma of using embryos for medical purposes. In the past four years they have figured out how to take normal skin cells, turn them into stem cells and then use those to grow the full range of cells found in our body. All over the world scientists are investigating the potential of stem cells – embryonic and adult – in treating conditions such as Parkinson’s, multiple sclerosis, spinal cord injuries, rheumatoid arthritis and retinal disease.
In the all the excitement, it’s easy to forget that most of the work has been done in the lab, usually involving frogs, rats and sheep, and although we may be on the cusp of a new era of regenerative medicine, we aren’t there yet.
However, should you Google “stem cell therapies” you will be directed to all sorts of therapies already available – in a pill form, through a clinic – promising things science can’t yet offer. To cut through all the persuasive marketing and muddled science, here’s where things are up to: there are a lot of stem cell therapies that cure diseases in animals, but only a handful have gone through to clinical trials. And all those trials are at phase 1 or 2 and yet to go phase 3, which is what is required before science can say a therapy is safe and effective.
“So, we have the evidence stem cell therapy can work in animal models, but we are still needing to cross the bridge to the clinical trials,” says Bronwen Connor, who leads a team, at the University of Auckland’s Centre for Brain Research, that is investigating the potential of stem cell therapy to treat brain injuries and disease.
Remember, she says, these are not necessarily benign therapies. “If you take aspirin, and you have a bad side effect, you stop taking aspirin, but if you put stem cells in the body and have a bad side effect, you can’t get them out. So you might think, ‘Oh, I’m going to take some of my fat stem cells and put them elsewhere in my body’, and that might be fine, but we need to check it’s okay … we need to know if it might result in something horrible like tumour formations, or whether it affects our immune systems, because we can’t get those stem cells back out again.”
As she also points out, stem cells tend to be region-specific, so those harvested from someone’s fat are unlikely to be useful for treating a neurological disorder, such as Parkinson’s. “I look on these websites and I can’t always tell what they’re putting in the patients. I’ve talked to patients who say they’ve been given animal stem cells rather than human stem cells. Many sites don’t say where the stem cells are from, or who the donor is.”
In other words, those selling stem cell therapies today not only are taking people’s money for nothing, and toying with the hopes of people with diseases and injuries that are currently incurable, but may be treating people with a therapy that could have disastrous consequences.
“Our biggest fear in the stem cell science community is that one of these clinics will have a terrible outcome, like a patient dying or developing cancers, and the rest of the public will say, ‘Oh, we don’t want stem cell therapy because it killed someone.’ That won’t be because the science isn’t right, but because some people have cavalierly gone off and created these clinics without the proper science behind them.”
NEW APPROACH TO HIV
Researchers at the University of Otago have been granted US$100,000 from the Bill & Melinda Gates Foundation for research aimed at working toward a cure for HIV. Currently, the reservoir of latently HIV-infected cells means patients must take anti-retrovirals for the rest of their lives to attack these cells as they become active. The team, which is working toward curing rather than suppressing the disease, hopes to synthesise a crucial HIV protein and use these to wake up latently infected cells all at once to drain a person’s HIV reservoirs en masse.
EXCESSIVE NEURONS
Male children and adolescents with autism have more prefrontal neurons and a heavier brain than other children, according to a study published in the Journal of the American Medical Association. This builds on two decades of research focusing on abnormal enlargement of the brain during autistic children’s first 18 months. As these neurons are produced before birth, the study’s findings suggest faulty prenatal cell birth or maintenance may be involved in the development of autism.
INGENIOUS MEASLES
Mayo Clinic researchers have discovered why measles spreads so quickly. The virus emerges in the trachea of its host, provoking a cough that fills the air with particles ready to infect the next host. The study, published in the journal Nature, found the measles virus uses a protein in the host to infect a strategic location in the throat, from where it can easily exit through the mouth.