Regulatory T cells in diabetes mellitus.

Immune system dysfunction causes dysregulation of immune homeostasis, which in turn leads to autoimmune diseases. Regulatory T cells (Tregs) are a specialized T-cell subpopulation that maintain peripheral tolerance and immune homeostasis. Diabetic patients are at an increased risk of developing cardiovascular diseases; thus, in terms of coronary risk, diabetes mellitus (DM) is considered coronary heart disease equivalent. Accumulating evidence indicates that Tregs play an important role in protecting against the development of various cardiovascular diseases. In this review, we provide an overview of the role of Tregs in the pathogenesis of DM, including type 1 DM, type 2 DM, latent autoimmune diabetes of adults, and gestational DM. In addition, we discuss the role of Tregs in diabetic complications, including cardiovascular diseases, nephropathy, neuropathy, and retinopathy. Tregs play a beneficial role in the pathogenesis of diabetes mellitus and diabetic complications, although the precise molecular mechanisms underlying the protective effect of Tregs against diabetes mellitus are still obscure. Collectively, modification of Tregs may provide a promising and novel future strategy for the prevention and therapy of diabetes mellitus and diabetic complications.