Fibroblasts adhesion and activity onto bioactive synthetic anterior cruciate
ligament prosthesis
J. Zhou1, S. Changotade1, M. Manassero2, F. Anagnostou 3, D. Lutomski1, B. Brulez 4, V. Viateau2 and V.
Migonney1
1
Laboratoire de Biomatériaux et Polymères de Spécialité, CSPBAT CNRS FRE 3043, Université Paris 13, Av
J-B Clément 93430 Villetaneuse, France, zhoujie127@hotmail.com 2 Ecole Nationale Vétérinaire d’Alfort, 7
Av Ch de Gaulle, 94700, Maisons Alfort, France, 3 Laboratoire de biomécanique et biomatériaux
ostéarticulaire UMR 7052 10 Av de Verdun, 75010 Paris, France, 4LARS, 5 rue de la Fontaine, 21560, Arc du
Tille, France
Introduction: In the 1980s, different polymers were
introduced in the fabrication of synthetic anterior
cruciate ligament (ACL) prostheses. Polyester PET was
preferred because of its elasticity and mechanical
resistance near to that of the natural ligament (Olson
1988; Ruiz 2002). Nevertheless, ruptures and synovitis
were too frequently observed mainly due to the abrasion
of the fiber structure and the uncontrolled inflammatory
response leading to low tissue integration (Laurencin
2005). In order to improve the host response which
depends on the physico-chemical properties of the
polymer surface, Migonney, Brulez et al 2003
developed a new bioactive PET ligament by grafting a
bioactive polymer onto the LARS ligament prosthesis
surface (Ciobanu 2006). This grafting was shown to
improve fibroblast cell adhesion, distribution and
activity (Migonney 2007). In this paper, the mechanism
at the origin of the improved cell response was
investigated onto bioactive polymer grafted (PG) and
non grafted (NG) synthetic ACL prostheses. Primary
fibroblasts from natural ACL of sheep were cultured
onto PG and NG fabrics and fibers and the cell response
on both surface was compared (1) adhesion strength of
cells under different proteins conditions, (2) kinetics of
collagen secretion (3) integrins expression. In addition,
synovial fluids of implanted sheep with PG and NG
ACL were analyzed.
Materials and Methods: The PET knitted fabric
provided by LARS society were grafted as described by
Migonney et al 2007. Primary ACL fibroblasts from
two years old female Pre-Alpes sheep were harvested
and cultured. Fibroblast cells (106 cells/mL) were
seeded onto PG and NG PET fabric samples previously
incubated with DMEM culture media supplemented
with 10% fetal calf serum. Adhesion strength of cells
seeded on PG and NG PET fabrics was evaluated after
pre-incubation of surfaces with different protein
solutions. : a) 10% fetal calf serum protein, b) 7µg/ml
collagen, c) 10.3µg/ml fibronectin, 4) 7µg/ml
Results and Discussion. Results show that: 1) The
grafting of a bioactive polymer at the surface of PET
fabric strongly improves the adhesion strength of cells
(see Fig 1): τ 50 for GP fabrics is more than twice higher
than that of the NG fabrics. 2) The adhesion strength
depends on the nature of the proteins present in the
assay (see Fig 2).
**
Fig 1. primary fibroblast cells adhesion strength, **: p<0.01
Fig.2 Comparison of cell adhesion percentage on NG and PG
PET samples previously adsorbed with proteins mixtures
solution
Cell adhesion percentages are systematically higher
when the PET fabric is grafted by the bioactive polymer
whatever the proteins solution. Nevertheless in the case
of grafted surfaces the presence of collagen is
determinant on the adhesion process. While the
presence of fibronectin improves the adhesion strength
of cells on both surfaces, it is not the case for collagen
which is efficient only for GP surfaces: collagen plays a
key role in the cell response to GP ACL.
Conclusions: Bioactive polymer grafted PET fabrics
exhibited improved biological response in terms of
increased strength and of activity of fibroblasts cells.
References
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