%0 Journal Article
%T Increased ¦Â-cell proliferation before immune cell invasion prevents progression of type 1 diabetes
%J -
%D 2019
%R https://doi.org/10.1038/s42255-019-0061-8
%X Type 1 diabetes (T1D) is characterized by pancreatic islet infiltration by autoreactive immune cells and a nearly complete loss of ¦Â cells1. Restoration of insulin-producing ¦Â cells coupled with immunomodulation to suppress the autoimmune attack has emerged as a potential approach to counter T1D2,3,4. Here we report that enhancing ¦Â-cell mass early in life, in two models of female non-obese diabetic (NOD) mice, results in immunomodulation of T cells, reduced islet infiltration and lower ¦Â-cell apoptosis, which together protect them from developing T1D. The animals displayed altered ¦Â-cell antigens; islet transplantation studies showed prolonged graft survival in the NOD-liver-specific insulin receptor knockout (LIRKO) model. Adoptive transfer of splenocytes from NOD-LIRKO mice prevented development of diabetes in prediabetic NOD mice. A substantial increase in the splenic CD4+CD25+Foxp3+ regulatory T cell (Treg) population was observed to underlie the protected phenotype since Treg-cell depletion rendered NOD-LIRKO mice diabetic. An increase in Treg cells coupled with activation of transforming growth factor-¦Â/SMAD family member 3 signalling pathway in pathogenic T cells favoured reduced ability to kill ¦Â cells. These data support a previously unidentified observation that initiating ¦Â-cell proliferation, alone, before islet infiltration by immune cells alters the identity of ¦Â cells, decreases pathological self-reactivity of effector T cells and increases Treg cells to prevent the progression of T1D
%U https://www.nature.com/articles/s42255-019-0061-8