Diabetes and autoimmune diseases: A promising discovery at Maisonneuve-Rosemont Hospital

Dr. Sylvie Lesage and Dr. Heather Melichar

Two researchers from Hôpital Maisonneuve-Rosemont have made a surprising discovery that promises to provide a better understanding of diabetes and autoimmune diseases.

White blood cells, type 1 diabetes and autoimmune diseases

The two groups the Hôpital Maisonneuve-Rosemont Research Centre, led by Dr. Heather Melichar and Dr. Sylvie Lesage, in collaboration with Dr. Colin Anderson at the University of Alberta, were studying why white blood cells destroy the pancreas and cause diabetes. Their research led them to some unexpected conclusions.

White blood cells, diabetes and the immune system

The immune system is made up of several types of white blood cells. These help us fight infections and prevent cancer. They are, in a way, our body’s guardian angels.

However, sometimes our immune system can attack our own organs. It is called an autoimmune disease. This is the case with type 1 diabetes. Here, the white blood cells of our immune system destroy the cells that produce insulin— the hormone secreted by the pancreas— thus preventing it from lowering the blood glucose level (i.e., the sugar level in our blood).

What is insulin used for?

Secreted by cells in the pancreas, insulin lowers the level of glucose (sugar) in the blood and promotes its use by the body’s tissues. This is why it is used in the treatment of diabetes.

The main white blood cells involved in type 1 diabetes are called T cells.

We really thought that… We were wrong

Until now, it was assumed that people who developed type 1 diabetes had more highly reactive T cells than those who did not.

Melichar and Lesage’s research revealed exactly the opposite! There are more weakly self-reactive cells, resulting in the development of autoimmune diseases such as diabetes.

Results that bring hope!

These new results, recently published:

• advance knowledge.
• enable:
• the opening of new avenues of research.
• the development of innovative therapeutic approaches to prevent diabetes and autoimmune diseases.

˃ Read CD5 levels reveal distinct basal T-cell receptor signals in T cells from non-obese diabetic mice, Wiley Online Library, February 3, 2021.