Osteochondral Repair and Electromechanical Evaluation of Custom 3D Scaffold Microstructured by Direct Laser Writing Lithography.

OBJECTIVE

The objective of this study was to assess a novel 3D microstructured scaffold seeded with allogeneic chondrocytes (cells) in a rabbit osteochondral defect model.

DESIGN

Direct laser writing lithography in pre-polymers was employed to fabricate custom silicon-zirconium containing hybrid organic-inorganic (HOI) polymer SZ2080 scaffolds of a predefined morphology. Hexagon-pored HOI scaffolds were seeded with chondrocytes (cells), and tissue-engineered cartilage biocompatibility, potency, efficacy, and shelf-life was assessed by morphological, ELISA (enzyme-linked immunosorbent assay) and PCR (polymerase chain reaction) analysis. Osteochondral defect was created in the weight-bearing area of medial femoral condyle for study. Polymerized fibrin was added to every defect of 5 experimental groups. Cartilage repair was analyzed after 6 months using macroscopical (Oswestry Arthroscopy Score [OAS]), histological, and electromechanical quantitative potential (QP) scores. Collagen scaffold (CS) was used as a positive comparator for and studies.

RESULTS

Type II collagen gene upregulation and protein secretion was maintained up to 8 days in seeded HOI. analysis revealed improvement in all scaffold treatment groups. For the first time, electromechanical properties of a cellular-based scaffold were analyzed in a preclinical study. Cell addition did not enhance OAS but improved histological and QP scores in HOI groups.

CONCLUSIONS

HOI material is biocompatible for up to 8 days and is supportive of cartilage formation at 6 months . Electromechanical measurement offers a reliable quality assessment of repaired cartilage.