22
LIVING
for people with Type 1 diabetes (T1D) produced by a
company called Vertex Pharmaceuticals. This is the first
demonstration of a patient with T1D achieving robust
restoration of islet cell function from such a cell therapy.
Shelton received the infusion of stem cells derived
from a human embryo in June last year. The cells are
now producing insulin sufficiently well for his body at
last to more or less control its own insulin and blood
glucose levels as it should do, hugely reducing the risk
of life-threatening hypoglycaemic events. It is the most
successful stem cell transplant so far in a diabetic patient
and Shelton's need for injected insulin has fallen by 90%.
"It's a whole new life, it's like a miracle," he said
in December last year. "I feel like I got released from
handcuffs. I came home that first day, my numbers were
textbook perfect and now everything is completely level.
I'm not sitting here saying where's my orange juice,
where's my pills, where's my shot? I don't need them. My
body now does it for me."
The success has galvanised the worldwide
community of people living with T1D as well as their
doctors. It comes, in part, from the pioneering work
of a neurobiologist called Doug Melton from Harvard
University in Boston, America. Thirty years ago, he
dropped everything to begin researching the condition
after a near-death experience with his baby son Sam, who
developed T1D at six months old. His older child Emma
was later diagnosed with it when she was 14.
"These promising results bring great hope that stem
cell-derived, fully differentiated islet cells could deliver
a life-changing therapy for people who suffer from the
relentless life-long burden of T1D," said Melton who went
on to pioneer Harvard's entire stem cell and regenerative
biology programme.
Vertex has invested hundreds of millions of dollars
in the stem cell project and is now recruiting more
volunteers in the USA and Canada to receive the
experimental treatment. According to the stem cell
industry news website BioInformant, there are at least 16
other companies in the hotly contested race for a viable
treatment to cure T1D - a breakthrough that would yield
billions of dollars to its discoverers and transform lives
(and health systems) worldwide.
Supportive structure
Specialists from Diabetes UK warn this breakthrough is
still some way off. They say the current generation of
replacement beta cells only start to release insulin when
exposed to very high blood glucose levels. It's becoming
clear that the surrounding supportive structure known as
an extracellular matrix, is key to their useful function.
Diabetes UK has invested £280,000 in a project led
by Dr Natasha Hill, a biomolecular scientist at Kingston
University. Her team is using a different type of matrix
taken from a mouse pancreas, to see if this can better
support the stem cells to turn into functioning beta cells.
The cells are then being transplanted back into mice to
see how well they function. First results are due later
this year.
Incidence of T1D, along with other allergies and
so-called autoimmune disease where the body attacks
itself is increasing by about 4% a year for reasons that
are not yet fully understood. There are around 400,000
people with the condition in this country, 29,000 of
them children.
The biggest barrier to widespread use of stem cell
transplants remains the risk of rejection and the need for
continuing anti-rejection drugs.
For the moment stem cell therapies are only being
tested in people with the severest forms of Type 1, who
suffer frequent dangerous hypoglycaemia attacks, or
hypo unawareness, where they experience none of the
physical symptoms of hunger and dizziness, sweating,
fatigue or fast pulse to warn them their condition has
become life-threatening. As research advances, it is
hoped stem cells-turned-beta cells could also be used to
boost beta cell supply in people with T2D and help them
to make enough of their own insulin to perfectly control
blood sugar levels.
Temp fix for T2D
In the meantime, private healthcare companies around
the world are offering the treatment as a temporary fix
for T2D but it is not yet clear how well the cells function
or how long they last. It's available in the UK from places
including the Harley Street Clinic in London which uses
donor stem cells, and BioEden in Nottingham which
uses stem cells from dental pulp. As with most new and
privately offered solutions, it's not for the faint-hearted
when it comes to budget.
This historic, first-in-human
transplant of gene-edited,
stem cell-derived pancreatic
cells for the treatment
of diabetes, designed to
eliminate the need for
immune-suppression
~ James Shapiro