Chondrogenic potential of PMSCs cultured on chondroitin sulfate/gelatin-modified DBM scaffold.

Abstract

Introduction: Osteoarthritis is one of the most common orthopedic diseases that gradually causes wear and damage to the articular Subchondral bone due to the destruction of articular cartilage. One of the basic challenges in cartilage tissue engineering is the choice of scaffold. In the design of the cartilage scaffold, it is useful to consider parameters such as porosity, water absorption, high mechanical resistance, biocompatibility, and biodegradability. Therefore, in this study, demineralized bone matrix (DBM), which inherently has these characteristics to some extent, was chosen as the basic scaffold.

Methods: The gelatin/DBM (G/DBM) and the chondroitin sulfate-gelatin/DBM (GCS/DBM) scaffolds were prepared, respectively, by incorporating gelatin or chondroitin sulfate/gelatin solution inside DBM pores, freeze-drying and crosslinking with EDC/NHS. The physicochemical, biological characteristics and chondrogenic potential of scaffolds were studied.

Results: According to the SEM results, the size of the DBM pores in the G/DBM and GCS/DBM scaffolds decreased (from almost 100-1500 µm to less than 200 µm), which reduced cell escape compared to the DBM scaffold. Also, crosslinking the scaffolds has greatly increased their compressive E-modulus (more than 8 times). The cytocompatibility and non- toxicity of all scaffolds were confirmed by acridine orange/ethidium bromide (AO/EB) staining. The evaluation results of chondrogenic differentiation of placenta-derived mesenchymal stem cells (PMSCs) on modified scaffolds, using the real-time PCR method, showed that the presence of CS in the GCS/DBM scaffold improved the expression of chondrogenesis markers such as Aggrecan (AGC) (~4 times) and collagen 2 (COL-2) (~2.2 times) compared to the DBM scaffold. Also, Alcian blue staining and immunohistochemical analyses of the scaffolds showed denser and more coherent GAGs and COL-2 protein synthesis on the GCS/DBM than the G/DBM and DBM scaffolds.

Conclusion: According to the results, the GCS/DBM scaffold can be a suitable scaffold for cartilage tissue engineering.