We all know that Type 1 diabetes is caused by immune system T cells attacking the islet cells in the pancreas that make insulin. But what specifically do T cells recognize as foreign, so that they kill the islet cells? Good question, which we are starting to answer, thus.
Hybrid Insulin Peptides Are Autoantigens in Type 1 Diabetes
We report here for the first time to our knowledge that HIP-reactive T cells can be observed in the peripheral blood of patients with newly diagnosed T1D. Analyses of PBMCs [peripheral blood mononuclear cells] from patients with new-onset T1D and control subjects without diabetes revealed that ∼30% of patients with T1D produce a robust IFN-γ [interferon-gamma] response to at least one HIP and that some patients respond to up to seven HIPs.
We isolated six nonredundant, antigen-specific T-cell clones, most of which reacted to their target HIPs in the low nanomolar range.