CD4 and type 1 diabetes mellitus: In a double transgenic T1D mouse model expressing influenza hemagglutinin (HA) under the rat insulin promoter, and in which CD4+ T cells are specific for the HA antigen, Casares et al. demonstrated the ability of pMHCII dimers to prevent T1D onset in prediabetic mice and to restore euglycemia in newly diabetic mice [54].