Functional cartilage repair capacity of de-differentiated, chondrocyte- and mesenchymal stem cell-laden hydrogels in vitro

Abstract

Objective The long-term performance of cell seeded matrix based cartilage constructs depends on (1) the development of sufficient biomechanical properties, and (2) lateral integration with host tissues, both of which require cartilage specific matrix deposition within the scaffold. In this study, we have examined the potential of tissue-engineered cartilage analogs developed using different cell types, i.e., MSCs versus chondrocytes and de-differentiated chondrocytes, in an established “construct in cartilage ring” model. Design Cell-laden constructs of differentiated chondrocytes, de-differentiated chondrocytes after 2, 5 or 8 population doublings, and MSCs were either implanted into a native cartilage ring immediately after fabrication (immature group) or pretreated for 21 days in a transforming growth factor-β3 (TGF-β3) containing medium prior to implantation. After additional culture for 28 days in a serum-free, chemically defined medium, the extent of lateral integration, and biochemical and biomechanical characteristics of the implants as hybrid constructs were assessed. Results The quality of integration, the amount of accumulated cartilage-specific matrix components and associated biomechanical properties were found to be highest when using differentiated chondrocytes. De-differentiation of chondrocytes negatively impacted the properties of the implants, as even two population doublings of the chondrocytes in culture significantly lowered cartilage repair capacity. In contrast, MSCs showed chondrogenic differentiation with TGF-β3 pre-treatment and superior integrational behavior. Conclusions Chondrocyte expansion and de-differentiation impaired the cell response, resulting in inferior cartilage repair in vitro. With TGF-β3 pre-treatment, MSCs were able to undergo sustained chondrogenic differentiation and exhibited superior matrix deposition and integration compared to de-differentiated chondrocytes.

Chondrogenic Potential of Peripheral Blood Derived Mesenchymal Stem Cells Seeded on Demineralized Cancellous Bone Scaffolds

“…This was consistent with previous studies which revealed differentiated MSCs expressed lower levels of COL 2 and higher levels of hypertrophic markers compared to chondrocytes2425. In contrast, some studies found the opposed evidence that the pre-differentiated MSC-seeded scaffolds produced enhanced or similar levels of COL 2 or AGC than chondroctyes26272829. The difference might be due to varied passage of the chondrocytes used in those studies.…”

The Scaffold–Articular Cartilage Interface: A Combined In Vitro and In Silico Analysis Under Controlled Loading Conditions

“…Allon et al [19] augmented polymers with adhesion proteins while Maher et al [18] used growth factor-augmented nanofibers. Fortier et al [16] and Rackwitz et al [39] augmented scaffolds with growth factors and stem cells, respectively, while Erickson et al [40] modulated the extent of mesenchymal stem cell maturation in the hopes of optimizing integration. Hunziker and Kapfinger [21] chose to partially, enzymatically digest the host cartilage in an effort to free chondrocytes that would be capable of migrating to the scaffold interface.…”

Cell Therapy and Tissue Engineering for Cartilage Repair

“…ACI is only applicable to small size (3-4 cm 2 ) focal lesions surrounded by healthy cartilage [15,28]. Other limitations are dedifferentiation of chondrocytes during culture expansion, the low amount of chondrocytes obtained and multiple surgical procedures involved [31,32]. Further, donor-site morbidity of cartilage and bone for chondrocyte and periosteum obtaining was observed [15,33,34].…”