Researchers from Europe have discovered that people with type 1 diabetes (T1D) have more beta cell-targeting immune cells in the pancreas than people without T1D. This is an interesting finding given that both groups have similar numbers of immune cells overall. This knowledge helps researchers further understand the process leading to T1D.
It’s thought that CD8+ T immune cells take part in the process leading to the destruction of insulin-producing beta cells. The aim of this study was to identify which features of these cells are linked with T1D.
The researchers analysed blood samples from people with and without T1D, and also used existing pancreas samples from JDRF’s nPOD program.
They found that CD8+ T cells that target the pancreas are present in similar numbers in the blood of both groups of people, and higher in children than in adults. These immune cells however were present in larger numbers in the pancreases of people with T1D.
Interestingly, the researchers also found a high level of these immune cells in the pancreas of someone who had experienced chronic inflammation of the pancreas.
These results indicate that although everyone has a similar level of these immune cells, another process happens in people with T1D that ‘activates’ the immune cells and leads to more of these cells heading to the pancreas to destroy beta cells.
It remains unclear exactly how these immune cells are activated. This research suggests that their frequency in the blood alone does not determine whether T1D will develop.
The research group has proposed a few different mechanisms that might be leading to activation. These are: the stresses that growth places on children’s metabolism; an immune system malfunction; or inflammation of the pancreas. The next step for the group is to carry out more research to work out which of these theories is the most likely explanation.
These findings, published in the journal Science Immunology, will help researchers and doctors to understand the disease’s progression. Combined with other research into the immunology of T1D, this could lead to new approaches for preventing and treating T1D as researchers can better target potential treatments.
What’s happening in Australia
JDRF is funding several projects within the immunology field, taking place at St Vincent’s Institute of Medical Research. These projects are investigating different aspects of the immune system that will work together to solve the mysteries of the different pathways in the body that lead to the development of T1D. One of the T1DCRN Innovation Award recipients, Associate Professor Stuart Mannering (above), is investigating specifically what it is on beta cells that the T cells ‘see’ to make them a target, which will provide invaluable knowledge to add to the immunology and T1D field.