47 research outputs found
Insulinâlike growth factorâ1 stimulates regulatory T cells and suppresses autoimmune disease
The recent precipitous rise in autoimmune diseases is placing an increasing clinical and economic burden on health systems worldwide. Current therapies are only moderately efficacious, often coupled with adverse side effects. Here, we show that recombinant human insulinâlike growth factorâ1 (rhIGFâ1) stimulates proliferation of both human and mouse regulatory T (Treg) cells in vitro and when delivered systemically via continuous minipump, it halts autoimmune disease progression in mouse models of type 1 diabetes (STZ and NOD) and multiple sclerosis (EAE) in vivo. rhIGFâ1 administration increased Treg cells in affected tissues, maintaining their suppressive properties. Genetically, ablation of the IGFâ1 receptor specifically on Treg cell populations abrogated the beneficial effects of rhIGFâ1 administration on the progression of multiple sclerotic symptoms in the EAE model, establishing a direct effect of IGFâ1 on Treg cell proliferation. These results establish systemically delivered rhIGFâ1 as a specific, effective stimulator of Treg cell action, underscoring the clinical feasibility of manipulating natural tolerance mechanisms to suppress autoimmune disease