Summary

Chondral lesions and osteoarthritis can lead to significant disability. This study describes biomechanical analysis for cartilage restoration by tissue engineering and cell therapy treatments in a GMP translational large animal model. TEC-treated cartilage showed better mechanical properties and resistance to deformation than untreated cartilage.

Abstract

Introduction

The chondral lesion and osteoarthritis are conditions associated with an economic burden, since if left untreated may cause changes in the biomechanics of the joint and result in several injuries considered highly disabling to the individual. Mesenchymal Stromal Cells (MSCs) have the immunomodulatory capacity and paracrine signaling that are useful for tissue bioengineering in the treatment of cartilage injuries. The articular cartilage is a viscoelastic material that can undergone structural and compositional changes; therefore, it is important to assess the physical properties of the tissue through mechanical evaluation. The differential of this study is that the cell culture process was carried out under Good Manufacturing Practices (GMP) conditions for use in humans. Objective: This study aims to describe biomechanical analysis for cartilage restoration by tissue engineering and cell therapy treatments in a GMP translational large animal model Methods: A controlled experimental study in fourteen Brazilian miniature pigs was performed, using scaffold-free Tissue Engineering Construct (TEC) from dental pulp and synovial MSCs with 6 months follow-up. To compare the cartilage with and without TEC, the indentation test consisted of three force-displacement cycles performed at a constant loading rate of 0.5 mm/min with a fixed displacement of 5% of the mean cartilage thickness. Results: From the indentation test, the Dynamic Modulus obtained from the second cycle was 1.68 ± 1.18 MPa in the untreated group and 2.81 ± 2.05 MPa in the treated group (p<0.05). The reduced modulus at 10% of the upper region of the second unloading curve, in the untreated group, was 2.56 ± 1.43 MPa, while in the group treated with TEC it was 5.40 ± 3.42 MPa (p<0.05). Conclusion: Treatment with TEC from MSC showed greater reconditioning capacity and resistance to elastic deformation compared to the untreated group.