New therapeutic approaches for type 1 diabetes: Disease-modifying therapies

Figure 3 Immunoregulatory function of mesenchymal stem cells in type 1 diabetes mellitus. The effects of mesenchymal stem cells ultimately result in downregulation in the proliferation and function of dendritic cells, cytotoxic T lymphocytes (CTLs), helper T (Th) type 1 and type 17 cells, natural killer (NK) cells and type 1 macrophages (M1). Meanwhile, mesenchymal stem cells increase the number of type 2 macrophages (M2) and regulatory T cells (Tregs), which can inhibit effector T cells and stimulate Th type 2 protective cells. Red arrow/line: Downregulation/inhibition; Green arrow/line: Stimulation. APC: Antigen-presenting cell; B: B cell; DC: Dendritic cell; GADA: Glutamic-acid-decarboxylase antibody; IA2: Islet tyrosine phosphatase 2 antibody; IAA: Insulin autoantibody; ICA: Islet cell antibody; IL: Interleukin; IFN-γ: Interferon γ; TGF-β: Transforming growth factor β; TNF-α: Tumor necrosis factor α; ZnT8: Zinc transporter 8 antibody.