Implanting insulin-producing cells into the eye could help treat diabetes
Diabetes is one of the most pressing health concerns of our time, and now Swedish scientists have demonstrated a new potential way to manage the disease. It turns out the eye might be a useful place to implant insulin-producing cells to control blood sugar levels.
In patients with type 1 diabetes, the immune system mistakenly attacks the insulin-producing cells in the pancreas, leaving the body unable to regulate blood sugar levels and leading to a host of health problems.
A promising emerging therapy involves growing new pancreatic cells from a patient’s stem cells, loading them into a device and implanting it into the body. Human clinical trials have shown success with this, but there’s a major catch – the immune system recognizes the device as foreign and rejects it. Immunosuppressant medications can counter that, but also leave the patient vulnerable to infections and other diseases.
Now, scientists at KTH Royal Institute of Technology and Karolinska Institutet have demonstrated a way to avoid rejection of the implant. While previous studies have implanted the device under the skin, for the new study the team placed it in the eye. As unpleasant as that sounds, the main advantage is that the eye doesn’t contain the kinds of immune cells that respond badly to the implant. Plus, it’s close to vasculature that allows the insulin to quickly reach the bloodstream, and scientists can easily monitor its function just by looking into the eye.
In their tests, the researchers developed a wedge-shaped device, measuring 240 micrometers long, and implanted it into the anterior chamber of the eye – the space between the cornea and the iris – in mice. The device contained micro-organs in the form of pancreatic islets, which produce insulin.
“We designed the medical device to hold living mini-organs in a micro-cage and introduced the use of a flap door technique to avoid the need for additional fixation,” said Wouter van der Wijngaart, co-corresponding author of the study.
In mouse tests, the team showed that the device was able to stay in place for the several-month duration of the experiments. The cells quickly integrated with the blood vessels in the eye and were able to function normally for the duration as well.
This proof-of-concept study shows that the eye is a promising location for cell-based therapies to treat diabetes, as well as other diseases.
“Ours is a first step towards advanced medical microdevices that can both localize and monitor the function of cell grafts,” said Anna Herland, lead author of the study. “Our design will enable future integration and use of more advanced device functions such as integrated electronics or drug release.”
The research was published in the journal Advanced Materials.