Modulation of cell attachment and collagen production of anterior cruciate ligament cells via submicron grooves/ridges structures with different cell affinity.

This study aimed to investigate the effects of submicron-grooved topography and surface cell affinity on the attachment, proliferation and collagen synthesis of anterior cruciate ligament (ACL) cells. Two grooved polystyrene (PS) surfaces (equal groove/ridge width of 800 nm) with a groove depth of 100 or 700 nm were fabricated and modified by oxygen plasma treatment, dopamine deposition and conjugation of RGD-containing peptides to enhance cell affinity. The elongation and alignment of ACL cells was enhanced by grooved structures with increasing groove depths regardless of surface chemistry. On the other hand, cell spreading and proliferation mainly depended on surface chemistry, in accordance with surface cell affinity: O(2) plasma < dopamine deposition < RGD conjugation. The synthesis of type I collagen was the highest by the ACL cells cultured on the 700 nm grooved surface conjugated with RGD peptides, indicating that both surface grooved topography and chemistry play a role in modulating collagen production of ACL cells. Furthermore, the type I collagen deposited on the 700 nm PS surface was aligned with grooves/ridges. Our results indicated that both ligand presentation and cell alignment are important in the physiological activities of ACL fibroblasts. Such information is critical for design of biomaterials for ACL tissue engineering.