Islet Cell Transplant
The Edmonton protocol – 6 years down the line.
In my article on Alternative Insulin Deliverers I spoke about the Edmonton Protocol, started in 2000, that involved islet cell transplant into patients with type 1 diabetes. 36 patients were involved in the study and received their transplants between 2000 and 2003.
In 2004 the results were reported as:-
19 no longer required insulin.
7 had partial islet function.
6 had rejected their islet graft.
4 had withdrawn from the trial.
The final results from this trial, which must have been eagerly awaited by many type 1’s, are now in.
The news is neither ‘all good’ or ‘all bad’ – pretty much the norm in diabetes treatment I would say.
Of the 26 patients left in 2006 the results are:-
5 no longer required insulin.
21 had partial islet function.
Although it is disappointing that not all patients are off insulin altogether, that the benefits for many have been short lived, it is still a great step forwards.
For those who have retained partial islet function there are still the benefits of having to take lower insulin doses and also protection against hypoglycemia unawareness ( a condition in which the diabetic can no longer sense the usual warning signs of a dangerous fall in blood sugar).
All is not ‘doom and gloom’.
Don’t forget that this was an ‘experiment’ of sorts. The folk it was used on could best be described as ‘worst case’ scenarios and yet 26 out of the 36 have some sort of improvement in their condition.
We also need to remember that prior to Professor Shapiro and his colleagues using this protocol the success rate for transplanted islet cells was only 2% at the one year mark. They achieved 80% at that stage.
I would certainly think that the researchers have the green light to continue working to find ways to make the treatment last for longer (forever? - we can but hope!).
Why…….?
Of course the first thing we ask is “Why did this not work for all”. I think that is best covered by a statement from Professor James Shapiro of the University of Alberta in Edmonton, Canada himself.
He felt that not enough cells survived the initial transplant and therefore the ones that did survive were overworked and burnt out – does this latter scenario seem familiar to you type 2’s out there?
Quote from Professor James Shapiro - "We've only got a small number of cells that end up engrafting and they're all having to work at maximum capacity."
"When an engine runs at 3 000 revs every minute of the day and doesn't get a break, eventually some of them start to burn out."
The researchers feel that with more work and a refinement of their methods they should be able to improve the success rate.
For people with severe brittle diabetes even a slight improvement may well seem worth any risk.
Due to the fact that, as in all transplants, drugs have to be given to suppress the immune system, the technique does have a risk factor. Though the immune suppressant drugs used in the trial were ones that were felt to cause the least harm some patients lost their transplanted islets because they stopped taking the immunosuppressants – they felt unable to cope with the side effects.
Future hope
There has always been the problem of a shortage of pancreatic organ donors for islet cell transplants, plus the fact that these cells can suffer severe damage in the period between the death of the donor and the transplant into the recipient. This is due firstly to toxins which circulate in the blood stream after brain death, then to time spent in cold storage and in transport.
In January 2005 Dr. James Shapiro, Dr. Koichi Tanaka and a team of Japanese surgeons at the Kyoto University Hospital performed an islet cell transplant using a living donor, a process which reduces the chances of cell damage caused by the above factors.
The donor was a healthy (had a compatible blood group & healthy glucose and insulin concentrations) 56 year old woman and the recipient was her 27 year old daughter.
The recipient had been diabetic since the age of 15 due to pancreatitis (inflammation of the pancreas) and often suffered severe hypoglycaemia attacks.
A portion of the mother’s pancreas was removed, the islet cells were isolated and then transplanted into the daughter. Apparently these cells started producing insulin just minutes after the transplant and so far the daughter has had greatly improved glucose control.
In fact she was slowly weaned off her insulin and 22 days after the transplant she no longer needed insulin injections and 2 months later this situation still existed.
The feeling is that the transplant could last up to 5 years and even if the woman needed insulin injections later on the dose would be lower than before and she would no longer suffer from hypoglycaemic attacks.
She does still have to take immunosuppressants, as did the patients receiving cells from a dead donor.
The health of both daughter and mother are being closely watched. For instance the possibility exists that the mother could develop diabetes herself due to the loss of around half of her pancreas.
This is an alternative option for people whose cultural taboos do not allow transplants from dead donors. This is the case, for instance, in Japan, (where this procedure took place) and so this woman had no other choice except to live with her condition or get islet cells from a live donor.
Live donors may also help to overcome the shortage of donors. It can take at least two, and often more, dead donor pancreases to make up enough islet cells for a single recipient whereas it takes only half a pancreas from a living donor to get the same effect. They appear to just be more potent.
Also one has to take into account the fact that this procedure may be working as well as it appears to be so far because this woman did not have autoimmune type 1 diabetes but developed it due to pancreatitis. This means that the islet cells did not need to be protected against the autoimmune disease that destroys them in normal type 1 diabetes.