CD4 and type 1 diabetes mellitus: Treatment with T1D-relevant (but PBC-irrelevant) BDC2.5/IAg7-NPs did not trigger cognate T-cell expansion (Fig. 1b–e), confirming that pMHC-based nanomedicines exclusively operate on autoantigen-experienced T-cells (BDC2.5-like CD4+ T-cells are not expected to undergo activation by their cognate beta cell autoantigen in the absence of diabetogenic autoimmunity)1.