Morphology and adhesion of human fibroblast cells cultured on bioactive polymer grafted ligament prosthesis

The anterior cruciate ligament (ACL) is the most important ligament for the knee stabilization. Unfortunately, it is also the most commonly injured. Synthetic polymers such as polyethylene terephthalate (PET) are widely used to fabricate ligament prostheses. In this study, we reported how to graft poly(sodium styrene sulfonate) (pNaSS) onto PET fabrics used to prepare ligament at a rate of about 4.5 times 10^-6 mol/g. In this study, we analyzed the morphology of human fibroblast MacCoy adhering onto the pNaSS grafted fabrics. Cell adhesion strength onto grafted and non grafted fabrics previously adsorbed with serum proteins was also evaluated after the application of shear stresses. Results showed that human fibroblast MacCoy adhered more strongly on the pNaSS grafted fabric compared to the non grafted one. The cell spreading is well on the grafted fiber even after the shear stress application: about 65% of cells remained adhered on the pNaSS grafted fabric as compared to 32% on the non grafted one. We concluded that Mac Coy human fibroblast cells strongly adhered onto the pNaSS functionalized PET prosthesis surface and showed a better spread cell morphology as well as a more homogeneous distribution than on the non grafted sample surfaces.

I. Introduction

The anterior cruciate ligament (ACL) is the most commonly injured ligament of the knee. Traditionally, ACL injuries have been treated by performing biological grafts: autografts, or allografts. Moreover, attempts have been made to use synthetic materials in the ligament replacement, for example, non-degradable synthetic materials such as polyethylene terephthalate (PET) [1]–[3]. However, despite the progresses in polymer science as well as in surgical techniques, the failure ratio of the synthetic implants remains too high. The modes of synthetic implant failures are fiber abrasion and fatigue, synovitis due to a foreign body reaction, and loss of the integrity of the textile due to biologic infiltration [4]. Therefore, the host response of PET is important and must be improved to reach a real “bio-integration” of the synthetic ACL. One possible method for improving the host response is to graft bioactive polymers onto the surface of the synthetic ACL.