The composite sandwich structure of dNCPs polyelectrolyte multilayers induced the osteogenic differentiation of PDLSCs in vitro

Abstract

This study reported about the fabrication of dentin non-collagenous proteins (dNCPs) polyelectrolyte multilayers and evaluated its osteogenic potential. The composite sandwich structure of dNCPs polyelectrolyte multilayers was generated on the surface of polycaprolactone electrospinning membranes by the Layer-by-Layer self-assembly technique. The dNCPs-coated membranes comprised the experimental group and the non-coated membranes acted as the control. Nanofiber morphologies of both membranes were observed under scanning electron microscope. The release of dNCPs was evaluated by ELISA kit. Periodontal ligament stem cells (PDLSCs) were seeded on both membranes. The morphology changes and proliferation of cells were tested. The expressions of osteogenic-related genes and proteins were evaluated by RT-PCR, alkaline phosphatase (ALP) activity assay, and immunofluorescence staining. dNCPs-coated membranes displayed significantly different fiber morphology than the non-coated membranes. A stable release of dentin phosphoprotein was maintained from day 4 to day 15 in the experimental group. Cells on dNCPs-coated membranes were found to have cuboidal or polygonal shapes. The proliferative rate of cells was significantly lower in the experimental group from day 4 to day 9 ( p<0.05). However, cells on the dNCPs-coated membranes demonstrated a significantly higher ALP content and expression levels of osteogenic gene and proteins than the controls ( p<0.05). These results indicated that dNCPs polyelectrolyte multilayers could induce the osteogenic differentiation of PDLSCs in vitro.