Mesenchymal stem cell -derived exosomes as natural nanoparticles (NPs) stimulate the growth of limbal stem cells (LSCs) by regulating Wnt/β-catenin, p38 MPAK and ERK pathway

Objective(s): In the current study, we investigated the impacts of the mesenchymal stem cell (MSCs)- exosome on limbal stem cells (LSCs) proliferation.Methods: Exosomes firstly were isolated from the human MSCs. Then, they characterized by expression of CD9, CD63 and CD81using the western blotting and morphological evaluation by transmission electron microscopy (TEM) image. The proliferation levels of treated LSCs were investigated following treatment with MSCs-exosome by MTT assay during the 1-4 days of exposure at 50-400 ng/ml concentrations. The expression levels of the beta-catenin, Wnt, p38 MAPK, and ERK were measured in LSCs within 12 and 96 hours of exposure.Results: MTT assay consequences exhibited that exosomes at concentrations of 50-400 ng/ml could boost the proliferation of the LSCs in vitro. Also, treatment caused the up-regulation of the expression of beta-catenin, Wnt, p38 MAPK, and ERK, partially or efficiently, in the LSCs.Conclusions: We suggested that the exosome is capable of provoking the proliferation of the LSCs by up-regulating the proliferation involved pathways.