Anti-MTOR polyclonal antibody

BackgroundPlacenta-derived mesenchymal stem cells (PD-MSCs) have unique immunomodulatory properties. Phosphatase of regenerating liver-1 (PRL-1) regulates the self-renewal ability of stem cells and promotes proliferation. Graves' ophthalmopathy (GO) is an autoimmune inflammatory disease of the orbit and is characterized by increased orbital levels of adipose tissue. Here, we evaluated the therapeutic mechanism for regulation of adipogenesis by PRL-1-overexpressing PD-MSCs (PD-MSCsPRL-1, PRL-1+) in orbital fibroblast (OF) with GO patients.MethodsPD-MSCs isolated from human placenta were transfected with the PRL-1 gene using nonviral transfection method. Primary OFs were isolated from orbital adipose tissue specimens from GO patients. After maturation as adipogenic differentiation, normal and GO-derived OFs were cocultured with naive and PD-MSCsPRL-1. We analyzed the protein levels of adipogenesis markers and their signaling pathways in OFs from GO patients.ResultsThe characteristics of PD-MSCsPRL-1 were similar to those of naive cells. OFs from GO patients induced adipocyte differentiation and had significantly decreased a lipid accumulation after coculture with PD-MSCsPRL-1 compared to naive cells. The mRNA and protein expression of adipogenic markers was decreased in PD-MSCsPRL-1. Insulin-like growth factor-binding proteins (IGFBPs) secreting PD-MSCsPRL-1 downregulated the phosphorylated PI3K/AKT/mTOR expression in OFs from GO patients. Interestingly, IGFBP2, -4, -6, and-7 expression in PD-MSCsPRL-1, which was mediated by integrin alpha 4 (ITGA4) and beta 7 (ITGB7), was higher than that in naive cells and upregulated phosphorylated FAK downstream factor.ConclusionIn summary, IGFBPs secreting PD-MSCPRL-1 inhibit adipogenesis in OFs from GO patients by upregulating phosphorylated FAK and downregulating PI3K/AKT/mTOR signaling pathway. The functional enhancement of PD-MSCs by nonviral gene modification provides a novel therapeutic strategy for the treatment of degenerative diseases.