CD4 and autoimmune disease: Cumulative findings have shown that nanomaterials are promising approaches to deliver autoantigen protein/peptides, DNA, and mRNA for induction of immune tolerance for the treatment of autoimmune diseases.658–661 One of the mechanisms behind it is that specific antigens can induce the generation and differentiation of tolerogenic APCs, which will drive the anergy, deletion, and apoptosis of pathogenic CD4+/CD8+ T cells and induction of Foxp3+ Tregs.