Human olfactory mucosa stem cells delivery using a collagen hydrogel: As a potential candidate for bone tissue engineering

Abstract

For bone tissue engineering, stem cell‐based therapy has become a promising option. Re-cently, cell transplantation supported by polymeric carriers has been increasingly evaluated. Herein, we encapsulated human olfactory ectomesenchymal stem cells (OE‐MSC) in the collagen hydrogel system, and their osteogenic potential was assessed in vitro and in vivo conditions. Col-lagen type I was composed of four different concentrations of (4 mg/mL, 5 mg/mL, 6 mg/mL, 7 mg/mL). SDS‐Page, FTIR, rheologic test, resazurin assay, live/dead assay, and SEM were used to characterize collagen hydrogels. OE‐MSCs encapsulated in the optimum concentration of collagen hydrogel and transplanted in rat calvarial defects. The tissue samples were harvested after 4‐ and 8‐weeks post‐transplantation and assessed by optical imaging, micro CT, and H&E staining meth-ods. The highest porosity and biocompatibility were confirmed in all scaffolds. The collagen hydro-gel with 7 mg/mL concentration was presented as optimal mechanical properties close to the naïve bone. Furthermore, the same concentration illustrated high osteogenic differentiation confirmed by real‐time PCR and alizarin red S methods. Bone healing has significantly occurred in defects treated with OE‐MSCs encapsulated hydrogels in vivo. As a result, OE‐MSCs with suitable carriers could be used as an appropriate cell source to address clinical bone complications.