HLA-DR*0401 expression in the NOD mice prevents the development of autoimmune diabetes by multiple alterations in the T-cell compartment

•T1D abrogation can be achieved through a multifaceted T-cell regulatory mechanism.•T-cell regulation involves mainly the Foxp3+ and IL-10+ CD4 T-cell subsets.•Human HLA-DR∗0401 allele induces Foxp3+ and IL-10+ CD4 T-cells.•HLA-DR*0401 transgenic expression in NOD mice prone to T1D abrogates the disease.•HLA-DR*0401 expression in humans may play a T-cell regulatory effect.