Effects of human fibronectin and human serum albumin sequential adsorption on preosteoblastic cell adhesion

Abstract

Fibronectin (Fn) is widely reported to promote cell adhesion and spreading, and recent reports attest to the synergistic effect of coadsorbed albumin (unexpected due to the passivating character of the latter protein). In this study, the sequential adsorption of fibronectin and albumin, and the morphology of cultured MC3T3-E1 preosteoblastic cells are investigated on three important biomaterial surfaces: silicon oxide, poly(styrene) (PS), and hydroxyapatite (HA). Using quartz crystal microgravimetry with dissipation analysis, the adsorbed protein composition and mechanics are determined. Interestingly, cell morphological changes correlate neither with the amount of Fn nor the rigidity of the protein layer. On the PS surface, Alb is seen to significantly diminish cell spreading, possibly due to Alb aggregation with a partially denatured initially placed Fn layer. HA appears to be a particularly favorable substrate for osteoblast adhesion, despite having low Fn adsorption and protein layer rigidity.

Experimental Characterization and Mathematical Modeling of the Adsorption of Proteins and Cells on Biomimetic Hydroxyapatite

“…In addition, cell spread also appeared to increase over the culture period, regardless of pre-incubation conditions for both HA and TCPS samples, indicating that the spreading is not an instantaneous process. Overall, this confirmed that proteins play a key role in the mediation of cell spread, this being particularly important for biomimetic HA surfaces, which are challenging substrates. , These results correlated well with a previous study where an increased spread of MC3T3-E1 pre-osteoblasts was found after 3 h of culture on HA pre-incubated with fibronectin and albumin as opposed to non-pre-incubated samples . In addition, Degasne et al demonstrated that Saos-2 osteoblasts cultured in FBS displayed a flat and spread-out morphology, whereas cells grown in serum-free medium were round and globular in morphology …”

“…In fact, lower cell numbers were detected after 6 h of culture for pre-incubated TCPS compared to non-pre-incubated TCPS (Figure C). These results may be explained by the denaturalization of fibronectin on TCPS, which could cause aggregation of other proteins such as albumin . To conclude, the pre-incubation process has to be carefully optimized for each material, since as shown, incubating the samples with a medium containing 10% FBS results in a quicker and enhanced adhesion of cells to HA but does not have a positive effect for TCPS.…”

ILK supports RhoA/ROCK-mediated contractility of human intestinal epithelial crypt cells by inducing the fibrillogenesis of endogenous soluble fibronectin during the spreading process

“…It is well known that exogenous proteins adsorb differently on surfaces with distinct properties which can cause variations in the properties (e.g. density, rigidity, topography, conformation and interactions) of the protein forming the coating, which in turn direct cell activity [69][70][71][72], including FN deposition and fibrillogenesis [73][74][75][76]. For example, the conformational change induced by the adsorption of soluble FN to plastic or its specific interaction with Col-I adsorbed to plastic prompt the binding and activation of α5β1 [ [37,77,78] and cell contractility [79].…”

Comparison of nanoparticular hydroxyapatite pastes of different particle content and size in a novel scapula defect model

“…observed agglomerations of the Ostim ® nanocrystals that became more dense over time, remaining embedded in bone and connective tissue without further resorption 11 . While single nanoparticles might provoke inflammatory responses and inhibitory effects 15 16 , agglomerates increased the fibronectin adsorption which influences osteoblast adherence 17 18 19 . The surface topography of HA plays a critical role in bone regeneration.…”