What does "immune mediated" mean when talking about DM 1?

Answer:
Autoimmune pancreatitis may sometimes attack beta-islet cells in the pancreas, which lowers insulin levels, producing type I diabetes mellitus. "Immune-mediated" just means that the immune system is attacking the body, resulting in the diabetic condition.

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It means your immune system is causing it.

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Type I diabetes is characterised by a decrease in the the number of Beta cells in the pancreas (these are the cells which produce insulin). There is evidence that this is caused by the body producing antibodies which bind to these cells. Some authorities think that a viral infection may cause damage to these cells and expose antigens to immune recognition which are normally not exposed to these cells hence triggering the disease.

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