Addition of Bone‐Marrow Mesenchymal Stem Cells to 3D‐Printed Alginate/Gelatin Hydrogel Containing Freeze‐Dried Bone Nanoparticles Accelerates Regeneration of Critical Size Bone Defects

Abstract

A 3D‐printed biodegradable hydrogel, consisting of alginate, gelatin, and freeze‐dried bone allograft nanoparticles (npFDBA), was developed as a scaffold for enhancing cell adhesion, proliferation, and osteogenic differentiation when combined with rat bone marrow mesenchymal stem cells (rBMSCs). This composite hydrogel was intended for the regeneration of critical‐sized bone defects using a rat calvaria defect model. The behavior of rBMSCs seeded onto the scaffold was evaluated through SEM, MTT assays, and quantitative real‐time PCR. In a randomized study, thirty rats were assigned to five treatment groups: 1) rBMSCs‐loaded hydrogel, 2) rBMSCs‐loaded FDBA microparticles, 3) hydrogel alone, 4) FDBA alone, and 5) an empty defect serving as a negative control. After 8 weeks, bone regeneration was assessed using H&E, Masson's trichrome staining, and immunohistochemistry (IHC). The 3D‐printed hydrogel displayed excellent adhesion, proliferation, and differentiation of rBMSCs. The rBMSCs‐loaded hydrogel exhibited comparable new bone regeneration to the rBMSCs‐loaded FDBA group, outperforming other groups with statistical significance (P value < 0.05). These findings were corroborated by Masson's trichrome staining and osteocalcin expression. The rBMSCs‐loaded 3D‐printed hydrogel demonstrated promising potential for significantly enhancing bone regeneration, surpassing the conventional clinical approach (FDBA).This article is protected by copyright. All rights reserved