The use of a novel PLGA fiber/collagen composite web as a scaffold for engineering of articular cartilage tissue with adjustable thickness.

It has been a great challenge to make the thickness of engineered cartilage adjustable to cover the range of both partial-thickness and full-thickness articular cartilage defects. We developed a novel kind of composite web scaffold that could be used for tissue enginnering of articular cartilage with the thickness adjustable between 200 microm and 8 mm. The composite web showed a unique structure having web-like collagen microsponges formed in the openings of a mechanically strong knitted mesh of poly(lactic-co-glycolic acid). The knitted mesh served as a skeleton reinforcing the composite web, while the web-like collagen microsponges facilitated cell seeding, cell distribution, and tissue formation. Bovine chondrocytes cultured in the composite web showed a spatially even distribution, maintained their natural morphology, and produced cartilaginous extracellular matrices such as type II collagen and aggrecan. The thickness of the implant can be simply adjusted by laminating or rolling the web sheets. Not only did the histological structure of the engineered cartilage patches match the bovine native articular cartilage, but also their dynamic complex modulus, structural stiffness, and phase lag reached 37.8, 57.0, and 86.3% of those of native bovine articular cartilage, respectively. The composite web could be an important scaffold for tissue engineering.