Effect of proteins derived from dental pulp stem cells on human retinal pigment epithelial stem cells

Background: In recent years, stem cells have provided hopes for the treatment of many diseases. However, these cells are not easily replicable and passagable under cell culture conditions. The aim of this study is to investigate the impact of proteins derived from dental pulp stem cells on human retinal pigment epithelial cells. Materials and Methods : Dental pulp stem cells were extracted following approved protocols at the Stem Cell Laboratory of Biotechnology Research Center under mycoplasma-free conditions. Subsequently, four concentrations of proteinase K were chosen: 100, 200, 300, and 400 µg/ml, and cells derived from dental pulp were incubated with these concentrations in adjacent medium for one hour. The metabolic activity of cells in different groups was assessed using the MTS assay at 3, 5, and 7 days, employing an ELISA reader for evaluation. Results: The secreted substances extracted from human dental pulp stem cells have a proteinaceous nature. These secretions possess the ability to proliferate retinal pigment epithelial cells. However, by removing proteins from the neighboring environment conditioned by dental pulp stem cells, the proliferative effect is eliminated. Conclusions: Treatment of the conditioned medium of dental pulp stem cells with proteinase K enzyme at a specific concentration, as determined by SDS-PAGE analysis, substantiates this claim.With the hope of utilizing secreted proteins in the treatment of more diseases.