Effect of nitrogen-rich cell culture surfaces on type X collagen expression by bovine growth plate chondrocytes

Abstract

BackgroundRecent evidence indicates that osteoarthritis (OA) may be a systemic disease since mesenchymal stem cells (MSCs) from OA patients express type X collagen, a marker of late stage chondrocyte hypertrophy (associated with endochondral ossification). We recently showed that the expression of type X collagen was suppressed when MSCs from OA patients were cultured on nitrogen (N)-rich plasma polymer layers, which we call "PPE:N" (N-doped plasma-polymerized ethylene, containing up to 36 atomic percentage (at.% ) of N.MethodsIn the present study, we examined the expression of type X collagen in fetal bovine growth plate chondrocytes (containing hypertrophic chondrocytes) cultured on PPE:N. We also studied the effect of PPE:N on the expression of matrix molecules such as type II collagen and aggrecan, as well as on proteases (matrix metalloproteinase-13 (MMP-13) and molecules implicated in cell division (cyclin B2). Two other culture surfaces, "hydrophilic" polystyrene (PS, regular culture dishes) and nitrogen-containing cation polystyrene (Primaria®), were also investigated for comparison.ResultsResults showed that type X collagen mRNA levels were suppressed when cultured for 4 days on PPE:N, suggesting that type X collagen is regulated similarly in hypertrophic chondrocytes and in human MSCs from OA patients. However, the levels of type X collagen mRNA almost returned to control value after 20 days in culture on these surfaces. Culture on the various surfaces had no significant effects on type II collagen, aggrecan, MMP-13, and cyclin B2 mRNA levels.ConclusionHypertrophy is diminished by culturing growth plate chondrocytes on nitrogen-rich surfaces, a mechanism that is beneficial for MSC chondrogenesis. Furthermore, one major advantage of such "intelligent surfaces" over recombinant growth factors for tissue engineering and cartilage repair is potentially large cost-saving.

Pituitary Adenylate Cyclase Activating Polypeptide (PACAP) Pathway Is Induced by Mechanical Load and Reduces the Activity of Hedgehog Signaling in Chondrogenic Micromass Cell Cultures

“…We have detected very similar pattern of the results in mRNA expression and protein levels during PACAP administration and oxidative stress in relation to other ECM proteins such as collagen type II and aggrecan core protein [ 22 ]. The elevated presence of collagen type X in the ECM is a key event during chondrocyte hypertrophy leading to calcification of cartilage matrix [ 48 ]. It is worthy of note, that a simultaneous significant elevation of the amount of type IX collagen may reflect on certain matrix reorganization upon mechanical load.…”

Mesenchymal Stem Cells for Treating Articular Cartilage Defects and Osteoarthritis

“…Recently, several promising reports have suggested that it is feasible to inhibit expression of collagens type I and X to control the chondrogenic differentiation pathway of MSCs (7,115,118,154). Bian et al showed that coculture of human MSCs with human articular chondrocytes in HA hydrogels enhanced the mechanical properties and cartilage-specific ECM content of tissue-engineered cartilage.…”

“…Petit et al showed that the extent of expression of type X collagen was reduced, at least transiently, upon growth on nitrogen-rich surfaces of both plated chondrocytes and MSCs from OA patients. This would enhance chondrogenesis (115). Rampersad et al found that growth on nitrogen-rich plasma-polymerized ethylene surfaces downregulated type X collagen expression in vitro when MSCs from OA patients were precultured on such surfaces before formation of pellet cultures.…”

Tissue engineering of functional articular cartilage: the current status

“…Furthermore, MSCs continue to express collagen type I (Steck et al 2005 ). Recently, several promising results have been published that show the feasibility of inhibiting collagen type I and X expression and thereby controlling the chondrogenic differentiation pathway of MSCs (Rampersad et al 2011 ; Petit et al 2011 ; Bian et al 2011 ; Fischer et al 2010 ).…”