P021 - Bone marrow-derived cells but not chondrocytes having a decisive role in a new cartilage matrix formation in an 3D model
Abstract
Purpose
Purpose: Despite the fact that cartilage repair techniques have been in use since relatively long time ago, a discussion about which cell type is responsible for cartilage regeneration during cartilage repair is still open. In our study, we have tried to provide some new facts about this issue.
Methods and Materials
Materials & Methods: A 3-D model in vitro, which should represent microfracture containing both chondrocytes and bone marrow-derived cells in different experimental conditions was made and the cells were cultured for eight weeks. Subsequently, the constructs containing our 3-D model were removed from the cell culture medium, fixed in paraffin and analyzed with immunohistochemistry.
Results
Results: Bone marrow - derived cells migrated to the upper compartment of the construct through a perforated nylon membrane containing both enzymatically digested- and non-digested particulated cartilage. The chondrocytes were identified by staining with S-100 and bone derived cells were detected with both SOX-9 and procollagen type I and II. Exclusively bone-derived cells have created new extracellular matrix as showed by SOX-9 and procollagen type I, II, and trichrome staining.
Conclusion
Conclusion: In our model in vitro bone-derived cells but not chondrocytes have shown to have an active role in new cartilage formation. Moreover, without particulated cartilage and chondroytes in the upper compartment these cells alone didn't have this effect. The last finding has shown, by our opinion, the need for chondrocyte presence for new cartilage formation, but it seems that the work itself has been done by other types of cells than chondrocytes.
