ACL fibroblast growth and matrix formation on different synthetic braided scaffolds visualized with SEM . Images were taken after 14 days of in vitro culture in 10% fetal bovine serum. (Left) Culture with PGA resulted in substantial matrix degradation from acidic byproducts. (Middle) PLA and PGA in a 82:18 mass ratio showed more sustainable matrix formation, particularly with the addition of fibronectin (Fn). (Right) PLLA scaffolds also displayed considerable matrix formation, which again was amplified by the addition of Fn. Reproduced with permission from Elsevier B.V.