PhD conferral Rick de Vries

A new medical implant to treat type I diabetes

Type I diabetes is an autoimmune disease in which the body's own insulin-producing cells, located in the islets of Langerhans, are destroyed by the body itself. Instead of continuous insulin injections, patients have the option of clinical islet transplantation. This involves placing donor islets in the patient's liver. However, the liver is not an optimal location and donor islets die quickly. This is why Rick de Vries and his colleagues investigated the development of a medical implant that can be placed outside the liver. On Friday, July 14, he will defend his PhD research at Maastricht University.

Insulin is produced in the islets of Langerhans, which are located in the pancreas. In type I diabetes patients, these islets are destroyed, so blood sugar levels can no longer be regulated properly. These patients must therefore inject insulin themselves regularly. A more durable solution to this problem is clinical islet transplantation, in which donor islets are placed in the liver. The most optimal location would be the pancreas, but due to a high risk of inflammation of the pancreas, the liver is currently used in the clinic. However, the liver also does not appear to be optimal, as donor islets still die in the long term due to oxygen deprivation and a strong immune response.

Medical implant

Rick de Vries and his colleagues investigated a solution to this problem: the development of a medical implant in which donor islets can be placed outside the liver. Extensive research into the design led to an implant with so-called microwells. These are porous cavities, each containing its own donor islet. In the laboratory, islets were grown in the microwells, which showed that the islets stay alive in the microwells rather than when the islets are grown separately. De Vries further investigated transplantation of this implant in animal models to determine the optimal location. The intramuscular site seems most promising. Indeed, due to the porosity of the model and location, new blood vessels began to form in the microwells, which should improve islet survival. Moreover, safety has been demonstrated in the relevant animal models.


However, the fact that the implant works in an animal and safety is proven says nothing about its application in humans. Hence, de Vries also conducted research into this translation. The first step is to enable large-scale production in a safe environment. This requires a clean room. This room is completely sterile to prevent contamination. Clean rooms have already been facilitated in a spin-off company called "Lighthouse Biomedical." This company, resulting from the findings of this research, aims to facilitate the production of the medical implants and eventually make them available to type I diabetes patients. But how? First, the safety of the implant must be investigated in humans. Normally, this so-called phase I of clinical research is performed in healthy subjects. In this case, however, it is not possible. The implant must be taken in combination with immunosuppressants to prevent rejection of the donor islets. These immunosuppressants suppress the immune system, making it unethical to administer them to healthy people.

Clinical trials are planned to begin within 1 to 2 years. First, a combination of clinical islet transplantation with the implant will be investigated, but the goal is to eventually replace the original procedure completely with the medical implant. An additional advantage is that fewer donors are needed, due to a greater survival rate of the islets in the implant. Thus, it will take some time, but perhaps in a few years type I diabetes patients will be able to opt for a truly sustainable treatment.

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