Intravenous immunoglobulin promotes the proliferation of CD4+CD25+ Foxp3+ regulatory T cells and the cytokines secretion in patients with Guillain-Barré syndrome in vitro

Intravenous immunoglobulin (IVIg) serves as the first line therapy in Guillain-Barré syndrome (GBS), however, its action mechanism remains unknown. We hereby stimulated peripheral blood mononuclear cells (PBMCs) from patients with GBS and healthy controls using IVIg and an IgG-derived natural Treg epitopes, namely Tregitopes. Our results showed that IVIg significantly promoted both the expansion of CD4+CD25+Foxp3+ regulatory T cells (Tregs) and secretion of IL-10 and TGF-β1 while Tregitopes promoted secretion of IL-10 and TGF-β1 only. Further study is necessary to elucidate the molecular mechanism of IVIg and Tregitopes on Tregs and the secretion of IL-10 and TGF-β1 in GBS. [Display omitted] •Reduced Tregs was negatively correlated with the clinical severity of GBS.•IVIg promoted the expansion of Tregs and secretion of IL-10 and TGF-β1 in cultured PBMCs.•An IgG-derived Treg epitopes, Tregitopes, promoted secretion of IL-10 and TGF-β1 in cultured PBMCs.