Proinsulin-specific T-cell responses correlate with estimated c-peptide and predict partial remission duration in type 1 diabetes.

CD4+ T-cell proliferative responses to proinsulin-containing autoantigens are common before and immediately after diagnosis of T1D but decline thereafter. Proinsulin33-63-specific CD4+ T-cell response is a novel marker of estimated residual endogenous β-cell function and predicts a better 2-year disease outcome.