The NOD.β2mKO.HHD.Ins2het mouse therefore has a variety of potential uses as a humanized model of T1D, including CD8 and CD4 T cell epitope identification, analysis of the relationship between thymic insulin expression and tolerance, and the evaluation of antigen-specific immunotherapies, particularly those targeting the immune response to insulin. The gene discussed is CD8A; the disease is type 1 diabetes mellitus.