Wayne Hawthorne
Human pancreatic islets (red) collected from a human donor
Australian researchers are taking the last steps to be the first in the world to remove cells from the pancreatic islets from genetically modified pigs and to transplant them into human patients. Your goal: cure type 1 diabetes.
In the culmination of decades of work, a team of researchers at the University of Sydney, Australia, have successfully removed viable cells from the pancreatic islets of genetically modified pigs.
“We are now trying to get to the point of transplanting these islet cells to diabetic patients,” he said Wayne HawthorneProfessor of Transplantation at Sydney University, Ao.
“We have animals thatobserve more than 2 years after transplantationwithout hyperaguda rejection, without rejection and with diabetes healed in this model Preclinical, ”added the investigator.
The pancreatic islets are clusters of cells in the pancreas who segregate insulinhormone that plays a crucial role in regulating blood sugar levels, allowing cells to absorb excess glucose. But in people with type 1 diabetes, The immune system attacks and destroys These cells.
If not treated, diabetes can cause, in the short term, complications potentially fatal such as diabetic ketacity, and even death. In the long run, the persistence of a high level of blood sugar can damage the blood vessels, leading to Nerves, Eyes, Kidney and Heart Problems.
At the other end of the scale, when the blood sugar levels of a patient are too low (hypoglycemia), This one has to ingest glucose. A “hypo” is usually accompanied by symptoms such as tremors, dizziness, swears or irritability, which can alert a person with diabetes they need to eat.
But, according to Hawthorne, There are some patients who can’t realize When the blood sugar level is low.
“If you can’t detect a low level of blood sugar, you can’t give yourself food or realize that you will get into a coma and die. So, unfortunately, many of these patients die,” he explains.
Hawthorne’s team has been treating diabetic patients with “alotransplantes“ – Transplants between humans. In the early 2000s, the team developed combined transplants parcene and rim, to treat a subset of patients who, due to bad luck in genetic lotterydevelop many secondary complications of type 1 diabetes, including renal failure.
“If we can put a pancreas, We can prevent them from being blindwho suffer nerve injuries, suffering from kidney failure or losing members, ”says Hawthorne.
Kylie Ironside / WIMR
Wayne Hawthorne (in the background, your team) shows a container with trangic pork pancreatic islets
O Pancreas is a large organwith many blood vessels, and transplants imply a large surgery that takes many hours and entails Many potential complications. The fact that it is done in combination with a kidney only increases the complexity of the procedure.
In addition, not all pancreas donated by a person in brain death will be ideal. THE age, excess fat, comoribility underlying, including vascular disease, may make it impossible to use the pancreas for an entire organ transplantation.
In times, these organs not ideal were intended for the garbage crate. Until, recalls Hawthorne, “About 30 years ago we thought… well, because we can’t take the pancreas and try to extract the cells from the islets?”
“We have developed a technology that allows us to put the pancreas into a mixer and extract the cells from the islets… It is a very complex procedure That I get 8 to 10 hours, but Not finally we are these bells cells of the separate islets, ”he explains.
The transplants of pancreatic islets are a Less invasive alternative transplants from integer organs, so they are suitable for a subset of DM1 patients and ignorance of severe hypoglycemia.
The cells are Infused in the patient’s liverwhere, after a few weeks, they begin to release insulin.
This restores the mechanism of biofeedback which allows patients to prevent hypoglycemia and can even fully eliminate the need for daily insulin injections. But in practice, the pancreas donated by patients with brain death They are not always large enough for this procedure.
“My specialty has always been to treat patients with type one diabetes all possible means… This meant allotransplants, but now we are considering the xenotransplantes“Says Hawthorne.
A xenotransplantation – Remove cells, tissues or organs of a particular species and put them in another species – It has been sought by clinicians and scientists since the 1960s as a solution to the global organs crisis.
This year, the US will start first clinical trials of genetically modified pigs transplantation in humans with terminal renal failure.
Os pigs are genetically modified to prevent the human immune system from Recognize your cells as strange.
Hawthorne and his colleagues Peter Cowanhead of immunology of ST Vincent’s Hospital Melbourne, and Mark Nottlefrom the University of Adelaide, developed their own Special lines of transgenic pigs.
“We have our own transgenic pigscompletely different from those of the United States, Europe, China, etc., and we did hard work for decades to we get to the point where we can use them in transplantations”, afirma Hawthorne.
The cells of these transgenic pigs were optimized to avoid rejection hyperaguda, immune rejection, coagulation and to provide additional immunosuppressive protection.
“I can potentially transplant them into a patient and administer the minimum amount of immunosuppression, which means it is applicable to a wider range of patients, ”says Hawthorne.
“The question continues to be if we will get health budget funds to do this, instead of dying from cancer or other diseases. The health system doesn’t have much money in the pot, ”laments the investigator.
