Encapsulated pancreatic cells in a new polymeric shell can completely replace regular insulin injections in type 1 diabetes mellitus.

The unique biomaterial, proposed by Boston scientists, allows implanted cells to withstand the attacks of the immune system and permanently provide the body's needs for its own insulin.

On the pages of two respected journals - Nature Medicine and Nature Biotechnology - the researchers reported that the experimental implant with beta-cells remained in the body of mice for six months and continued to produce insulin, replacing hormone injections by 100%.

Type 1 diabetes mellitus is the result of destruction of insulin-producing pancreatic cells by the patient's own immune system. Unable to synthesize insulin, the body can no longer control glucose metabolism, which, without treatment, leads to serious complications.

Now patients with type 1 diabetes have to check their sugar several times a day and do insulin injections. The only alternative so far is only the transplantation of islet cells, which requires additional medications and still does not give a person eternal freedom from injections.

Although similar procedures have already been performed in hundreds of patients with type 1 diabetes, their success is limited, since the immune system ultimately destroys foreign cells, even in spite of modern sophisticated treatments with immunosuppressors.

That's why the active search for ways to protect implanted cells worldwide continues.

Biomaterial that deceives the immune system.

A group of scientists from the Massachusetts Institute of Technology and Harvard University, as well as their colleagues from the Boston Children's Hospital, developed and tested on animals a new biomaterial that helps implanted cells "hide" from the recipient's immune system.

For the production of implants, a new method of growing island cells was used, described by Harvard professor Douglas Melton (Douglas Melton). A suitable biomaterial for protecting these cells appeared to be an alginic acid derivative (alginate).

Using an alginate-based gel, it was possible to successfully encapsulate islet cells without damaging them. This is because the polymer gel allows nutrients (carbohydrates, proteins) to flow freely into the cell, so it lives fully and reacts to changes in the body.

The problem is that conventional alginate does not protect the cells from attack from the immune system, so the implant cells quickly stopped working and died, and the implant cicatrized.

Experimenting with new polymer variants, scientists began to attach various small molecules to the polymer chain in the hope that they would protect the contents from immune cells. And for the first time in history, they did it: encapsulated cells lived in the body of rodents up to 6 months!.

The new biopolymer was built on the basis of triazole-thiomorpholine dioxide (TMTD).

If in the body of mice working cells lived up to 174 days, then on primates so far, they checked only the empty shell of TMTD. The result was promising: at least half a year without scarring.

"Now it is very important to see how long cells will live in the body of primates. If you can reproduce the results in monkeys and then in humans, then we can safely talk about a revolution in the treatment of type 1 diabetes, "said Dr. Sarah Johnson of JDRF.

If everything goes well, then in the future for the treatment of diabetes it will be enough every month to make an intraperitoneal injection of encapsulated cells. And all: your sugar is under reliable control.

medbe. en.

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