Fabrication of collagen based hydrogel nanocomposite scaffolds for cartilage tissue engineering using dental pulp stem cells

Abstract

Introduction: Molecules encapsulation technology for locally growth factor release is a promising strategy for establishing a sustained delivery system useful for either drug delivery or tissue engineering purposes. Aims: This investigation proposed to compose innovative nanocomposite biomaterials that enhance chondrogenic differentiation of human dental pulp stem cells (h-DPSCs) pathway for in-vitro cartilage regeneration. Methods: Here, we describe the design and development of the PLGA-collagen / PLGA-PEG-PLGA and gelatin/ PLGA-PEG-PLGA nanocomposite scaffolds containing TGF-β1 synthesized by freeze-drying technique. PLGA-PEG-PLGA nanoparticles were employed as a delivery system embedding TGF-β1 as an articular cartilage repair therapeutic agent. Results: Gelatin/ PLGA-PEG-PLGA and PLGA-collagen/PLGA-PEG-PLGA nanocomposite scaffolds caused the proliferation of hDPSCs and TGF-β1 promoted differentiation of hDPSCs at the same time. The results of the adhesion and MTT tests proved that the most significant feature of our research is that the scaffolds produced are biocompatible. The SEM observations demonstrated the compatibility and adhesive capability of our scaffolds for the h-DPSCs, and their potential to promote appropriate cell growth that could be advantageous in applications for cartilage tissue engineering. Homogeneous distribution of h-DPSCs on the gelatin/ PLGA-PEG-PLGA and PLGA-collagen / PLGA-PEG-PLGA scaffold surface suggested that these nanocomposite scaffolds have sufficient potential for cell adhesion, proliferation, and differentiation as well. According to the RT-PCR results, ECM components production, such as aggrecan, collagen type II, and Sox-9 were verified to be comparable to those in the native cartilage tissue. Both gelatin/ PLGA-PEG-PLGA and PLGA-collagen / PLGA-PEG-PLGA nanocomposite scaffolds, in addition to maintaining the required biological properties, also has acceptable mechanical properties.Conclusion: Altogether, due to their potential for the growth and differentiation of hDPSCs, gelatin/ PLGA-PEG-PLGA-TGF-β1 and PLGA-collagen/PLGA-PEG-PLGA-TGF-β1 nanocomposite hydrogels are likely to be suitable biomaterials for cartilage tissue regeneration.