MPO and Autoimmunity: To determine whether these sequences could induce anti-MPO autoimmunity we immunized C57BL/6 mice with individual 20-mers and measured T-cell reactivity to either the immunizing peptide, MPO409–428, or recombinant mouse (rm)MPO using interferon-γ (IFN-γ) and interleukin (IL)-17A ELISPOTs and [3H]-T proliferation assays.