Diabetes vaccine gives promising results in a genetic subgroup, according to a clinical research by Linköping University.

The researchers wanted to see whether type 1 diabetes immunotherapy might keep the body's own insulin production stable. The results show that injecting a protein called GAD into lymph nodes could be useful in a group of people.

The immune system destroys the cells that contain insulin in type 1 diabetes. The the body cannot control blood sugar levels once the insulin-producing cells have died, and a person with type 1 diabetes must use exogenous insulin for the rest of his or her life.

One of the most pressing questions in type 1 diabetes research is if and how the immune system's attack can be slowed or even stopped. One possible approach is to change the immune defence by injecting a protein that the immune system's cells respond to by way of a vaccine. GAD65 is one of the proteins against which the immune system often produces antibodies in type 1 diabetes (glutamic acid decarboxylase).

Professor Johnny Ludvigsson of Linköping University has been researching the idea of vaccinating people with type 1 diabetes who have recently been diagnosed with GAD for many years. The immune system is hoped to become more tolerant of the body&s own GAD and avoid killing insulin-producing cells, allowing the body to continue to produce some insulin.

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Type 1 Diabetes Vaccine

The effect of GAD-alum (Diamyd) injections into the lymph nodes of 109 young people with newly diagnosed type 1 diabetes was examined in DIAGNODE-2, which is a clinical phase 2 review. The participant's natural insulin output was evaluated at the beginning of the study and again after 15 months. Changes in long-term blood sugar levels (HbA1c) and how much additional insulin the patients required to take every day were among the other outcomes monitored.

Previous research on diabetes immunotherapy has proposed that genetic factors affect how patients respond to the treatment. This prompted DIAGNOSE-2 researchers to investigate many variants of what is known as & "HLA genes" These genes code for proteins found on the cell&s surface. They act as protein holders and reveal proteins to immune system cells passing by. If the protein fragment is from bacteria, for example, the immune system should produce antibodies to fight the foreign protein.

The immune system, on the other hand, can often respond to the body's own substances, and some HLA types have been linked to an increased risk of type 1 diabetes. HLA-DR3-DQ2 introduces the GAD65 protein to immune system cells, and patients with this variant often develop antibodies to GAD65 at an early stage of the disease. The HLA-DR3-DQ2 variant was found in around half of the
study participants.

The degree to which insulin output was maintained in the entire patient group did not vary between treatment and placebo. However, GAD-alum had a positive effect on the subgroup of patients who had the DR3-DQ2 HLA gene variant. No undesired results that could be connected to treatment with GAD-alum were seen during the study.