Type 1 diabetes breakthrough as stem cells make billions of human insulin cells

Date: Oct-10-2014 In what is being described as an important advance in the field of stem cell research, a

new study reveals how scientists successfully created billions of insulin-producing pancreatic

beta cells from embryonic stem cells.

Stem cells are a class of undifferentiated cells that are able to differentiate into specialized cell types such as skin, muscle and bone.

Writing in the journal Cell, the Harvard stem cell researchers describe how they

also transplanted the stem cell-derived beta cells into the kidney of a diabetic mouse that, 2

weeks later, showed no signs of the disease.

The study is a breakthrough for patients with type 1 diabetes and some with type 2 diabetes,

who require daily injections of insulin because they cannot make their own.

"We are now just one preclinical step away from the finish line," says Douglas Melton, who

co-chairs the department of stem cell research and regenerative biology at Harvard University in

Cambridge, MA.

The preclinical step that he refers to is securing a way to stop the immune system from

destroying the newly formed beta cells.

Working to protect the beta cells

Type 1 diabetes is an autoimmune disease whereby the body destroys insulin-producing beta cells

in the pancreas. Without insulin, the body cannot control glucose, which can lead to high

levels of blood sugar that eventually damage tissues and organs.

For their new technique to work in people with type 1 diabetes, the researchers need to

add another component that stops a recipient's immune system from attacking the 150 million or

so beta cells they would receive.

To this end, the team is already collaborating with colleagues at the Massachusetts Institute of Technology (MIT) to develop an implant

that protects the stem cell-derived beta cells from immune attack.

Prof. Melton says the device is currently undergoing tests and has so far protected beta cells

implanted in mice from immune attack for many months. "They are still producing insulin," he

adds.

Stem cell-derived cells have all the hallmarks of fully functioning, mature beta cells

While other research teams have generated beta cells from stem cells before, those cells lack many of the

hallmarks of fully functioning, mature beta cells. However, Prof. Melton and colleagues say their stem cell differentiation method can generate

hundreds of millions of glucose-responsive beta cells that have all the hallmarks of mature beta

cells. For example, they:

Express markers found in mature beta cells
Produce a calcium ion (Ca2+) response to glucose
Package insulin into secretory granules
Secrete quantities of insulin comparable to adult beta cells in response to various glucose

challenges.

"Furthermore," they note, "these cells secrete human insulin into the serum of mice shortly

after transplantation in a glucose-regulated manner, and transplantation of these cells

ameliorates hyperglycemia in diabetic mice."

The researchers are now testing the stem cell-derived beta cells in animal models, including

non-human primates.

Experts hail the study as a breakthrough. Prof. Elaine Fuchs of Rockefeller University - a

Howard Hughes Medical Institute investigator who was not involved in the study - says it is one

of the most important advances in the field of stem cell research:

"I join the many people throughout the world in applauding my colleague for this remarkable

achievement. For decades, researchers have tried to generate human pancreatic beta cells that

could be cultured and passaged long term under conditions where they produce insulin. Melton and

his colleagues have now overcome this hurdle and opened the door for drug discovery and

transplantation therapy in diabetes."

Medical News Today also recently learned of another study that suggests it may be

possible to tackle type 2 diabetes at its root by getting

rid of the excess fat inside liver and muscle cells that interferes with their ability to use

insulin.

Written by Catharine Paddock PhD

Not to be reproduced without permission.

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.