Preparation hydrogelic scaffold contained growth factor for application in skin repair using adipose-derived stem cells

Abstract

Background: Increasing demand for skin regenerative therapies suggests that keratinocyte-like cells (KLCs) should be produced in vitro. Engineering scaffolds to mimic natural human body conditions could provide a powerful substrate for KLC generation. On the other hand, platelet-derived growth factor-BB (PDGF-BB) is a polypeptide growth factor generated by platelet granules faced to cytokines. It plays a role in forming and remodeling various tissue types, including epithelial tissue, through interaction with cell-surface receptors on most mesenchymal origin cells. However, it breaks down quickly in biological fluids, emphasizing the importance of preserving them from biodegradation. To address this challenge, we formulated and evaluated PDGF-encapsulated nanospheres using PCL-PEG-PCL for sustained release of PDGF-BB to human adipose-derived stem cells (hADSCs). Aims: To prepare a natural biodegradable hydrogel scaffold containing growth factor-loaded poly (ester) nano- and microspheres for application in dermal wound healing using adipose-derived stem cells.Methods: This research prepared a novel hydrogel scaffold containing platelet-derived growth factor to induce hADSCs into KLCs. For this purpose, a PCL-PEG-PCL copolymer was synthesized and the platelet growth factor was encapsulated in it by the triple emulsion (W/O/W) method. A gelatin-collagen scaffold containing these nanoparticles was prepared and characterized.Results: The analysis of scaffold morphology revealed two interconnected porous structures with pore sizes of approximately 100 μm and 70 μm, respectively. Other characteristics such as swelling behavior, mechanical properties, and porosity were also evaluated under experimental conditions. The swelling ratios of the scaffolds were 20/1 and 11, the Young's moduli were 640 kPa and 771 kPa, and the porosity of the scaffold without nanoparticles containing growth factor was 19% higher than that of the scaffold containing them. The release profile of PDGF-BB from PCEC nanoparticles was steady and continuous over 504 hours, with a maximum release of 87%. Subsequently, hADSCs were cultured in the scaffold and differentiated into KLCs over 21 days. The differentiation of KLCs was confirmed using microscopy, Western blotting, and RT-PCR analysis. Based on the analysis of the cell culture hydrogel, gelatin-collagen/PDGF-BB hydrogels improved the adhesion, viability, and differentiation of hADSCs into keratinocytes.Conclusions: As a result, these data suggest that gelatin-collagen/PDGF-BB hydrogels can serve as a three-dimensional matrix for hADSCs, aiding their function in vitro, which can be used to develop new effective strategies for wound healing.