Immunomodulatory agents and cell therapy for patients with type 1 diabetes

Type 1 diabetes (TID) is a chronic disease caused by autoimmune destruction of pancreatic β-cells, that progresses in three stages: 1) stage 1: β-cell autoimmunity + normoglycemia; 2) stage 2: β-cell autoimmunity + mild dysglycemia; 3) stage 3: symptomatic disease + hyperglycemia. Interventions to prevent or cure T1D in the various stages of the disease have been pursued and may target the prevention of the destruction of β cells, regression of insulitis, preservation or recovery of β cells residual mass. Some therapies show promising results that might change the natural history and the approach to patients with T1D in the next few years. Teplizumab, a humanized monoclonal antibody that binds to CD3, was recently approved in the USA to delay Stage 3 T1D in individuals ≥ 8 years of age. Other non-cellular immunomodulatory therapies, both antigen-specific and non-specific, have shown interesting results either in patients with stage 2 or recent onset stage 3 T1D. Cell therapies such as non-myeloablative transplantation of autologous hematopoietic stem cells, mesenchymal stem cells, and tolerogenic dendritic cells have been also studied in these individuals, aiming immunomodulation. Stem cell-derived islet replacement therapy is promising for patients with long- standing T1D, especially with asymptomatic hypoglycemia not resolved by technology. This review aimed to provide updated information on the main immunomodulatory agents and cell therapy options for type 1 diabetes.