Effect of electrohydrodynamic printing scaffold with different spacing on chondrocyte dedifferentiation.

Background: Osteoarthritis (OA) is a common degenerative disease. Chondrocyte dedifferentiation can accelerate the progress of OA. Three-dimensional printing (3DP) is widely used in tissue regeneration applications. A three-dimensional (3D) culture system with 3D printed scaffolds could reduce the dedifferentiation of chondrocytes during passages, which would be a potential method for chondrocyte expansion.

Methods: The viability and proliferation of chondrocytes on scaffolds and effects of scaffolds with 100, 150, 200, 250 or 300 µm spacing on chondrocyte dedifferentiation were analyzed . The morphology of scaffolds and cell/scaffold constructs was observed by scanning electron microscopy (SEM). Glycosaminoglycan (GAG) was evaluated by Alcian blue staining. The effects of different spacing on chondrocyte dedifferentiation were evaluated by the messenger RNA (mRNA) and protein levels of cartilage-related genes.

Results: With more binding sites, the proliferation and viability of chondrocytes on scaffolds with 100 and 150 µm spacing were better than those with 200, 250 and 300 µm spacing on day 1, but this advantage diminished over time. The histology and quantitative real-time polymerase chain reaction (qRT-PCR) results showed that 200 µm spacing inhibits chondrocyte dedifferentiation better.

Conclusions: 3D printed scaffolds with 200 µm spacing can inhibit chondrocyte dedifferentiation, providing a basis for the future study of 3D printed scaffolds as an effective method for chondrocyte expansion.