Fibronectin adsorption

Michael KE, Vemekar VN, Keselowsky BG, Meredith JC, Latour RA, Garcia AJ (2003) Adsorption-induced conformational changes in fibronectin due to interactions with well-defined surface chemistries. Langmuir 19 8033-8040... 

Protein adsorption is the first event that takes place on material surfaces when blood or other body fluids are brought into contact with any material. Therefore, cell - material interactions must be discussed by taking into consideration the species and the nature of the protein adsorbed on the material surfaces. For instance, a series of cell-attachment and spreading experiments [11] of fibroblasts on the surface of modified polystyrene (TCP and Primaria) carried out in the presence of fetal calf serum (FCS) showed that FCS contains components which tend to decrease the attachment and spreading of fibroblast cells. The effect of these nonadhesive components was only evident when the FCS was depleted of vitronectin, showing that vitronectin overcomes the effect of these nonadhesive components and promotes cell-attachment and spreading on the polystyrene surface. Fibronectin, on the other hand, does not play a principal role in this fibroroblast adhesive process (Fig. 2). 

Partial results of the calculation are cited in Table 2, which shows that the work of adhesion is expressed as a bell-shape curve. In other words, the maximal adsorption of protein takes place on polymer surface having intermediate hydrophilicity. Ikada et al. confirmed this by the results of BSA adsorption on 8 polymer surfaces [12], and also by those of albumin and fibronectin adsorption on 13 polymer surfaces [14]. L-Cell attachment also showed a bell-shape profile [15],... 

Cooper et al. [21, 22] reported in detail the results of their laborious work on the adsorption of four proteins human serum albumin (HSA), fibrinogen (FGN), fibronectin (FN), and vitronectin (VN), on five biomaterials polyethylene (PE), silicone rubber (SR), Teflon-FEP (FEP), poly(tetramethylene oxide)-poly-urethane (PTMO-PU), and polyethylene oxide)-polyurethane(PEO-PU). Hard segments of these polyurethanes are composed of a methylene-bis(p-phenylisocyanate) (MDI) chain extended wih 1,4-butanediol. 

If we consider that cell adhesion under biological circumstances is mainly brought about with the aid of preadsorbed protein on the material s surface, we may explain the unique behavior of amino-containing materials against the cell-adhesion process in terms of the reduced residence-time of protein molecules at the interface. Actually, a recent study [129] revealed that the surface of polyamine-gra/t-polystyrene copolymer (SA) containing 6 wt.% polyamine portion exhibited a minimal adsorptive property against bovine plasma fibronectin (FN) and vitronectin (VN), both of which are known to mediate cell-adhesion processes. 

Other workers have observed concentration-dependent competitive adsorption, including Grinnell and Feld 89) (fibronectin), and Breemhaar et al. 104) (fibrinogen, IgG, albumin). 

Whitesides and coworkers describe the use of an elastomeric membrane to pattern proteins and cells on bacteriological polystyrene (PS), glass, and poly(dimethyl-siloxane) (PDMS) substrates [92], A patterned PDMS membrane was casted from lithographically structured photoresists and brought into close contact with the substrates (Fig. 6). When incubated with a solution of fibronectin (FN), adsorption of the cell-adhesion-mediating protein to the surface was restricted to the exposed areas. The membrane was peeled off and cells were seeded from a serum-free medium. Passivation to cell attachment of the untreated portions of the surface was achieved by adding 1% bovine serum albumin (BSA) to the cell-seeding medium, which... 

Grinnell F, Feld MK (1981) Adsorption characteristics of plasma fibronectin in relationship to biological-activity. J Biomed Mater Res 15 363-381... 

Fabriziushoman DJ, Cooper SL (1991) Competitive adsorption of vitronectin with albumin, fibrinogen, and fibronectin on polymeric biomaterials. J Biomed Mater Res 25(8) 953-971... 

Specific domains of proteins (for example, those mentioned in the section Organic Phase ) adsorbed to biomaterial surfaces interact with select cell membrane receptors (Fig. 8) accessibility of adhesive domains (such as specific amino acid sequences) of select adsorbed proteins may either enhance or inhibit subsequent cell (such as osteoblast) attachment (Schakenraad, 1996). Several studies have provided evidence that properties (such as chemistry, charge, and topography) of biomaterial surfaces dictate select interactions (such as type, concentration, and conformation or bioactivity) of plasma proteins (Sinha and Tuan, 1996 Horbett, 1993 Horbett, 1996 Brunette, 1988 Davies, 1988 Luck et al., 1998 Curtis and Wilkinson, 1997). Albumin has been the protein of choice in protein-adsorption investigations because of availability, low cost (compared to other proteins contained in serum), and, most importantly, well-documented conformation or bioactive structure (Horbett, 1993) recently, however, a number of research groups have started to examine protein (such as fibronectin and vitronectin) interactions with material surfaces that are more pertinent to subsequent cell adhesion (Luck et al., 1998 Degasne et al., 1999 Dalton et al., 1995 Lopes et al., 1999). 

Select proteins that mediate adhesion of specific anchorage-dependent cells (such as osteoblasts, fibroblasts, and endothelial cells) on substrate surfaces have been identified (Underwood and Bennett, 1989 Thomas et al., 1997 Ayad et al, 1994). For example, adsorption of fibronectin and vitronectin on tissue-culture polystryene subsequently enhanced osteoblast, fibroblast, and endothelial cell adhesion (Underwood and Bennett, 1989). More importantly, fibronectin and vitronectin adsorption on borosilicate glass, in a competitive environment, maximized fibroblast and osteoblast adhesion, respectively (Thomas et al., 1997). Ayad et al. (1994) reported that enhanced adsorption of laminin on tissue-culture polystyrene promoted subsequent endothelial cell adhesion. These studies provided evidence that adsorption of specific protein(s) can, subsequently, control select cell adhesion on material surfaces. 

Investigations of the underlying mechanism(s) revealed that the concentration, conformation, and bioactivity of vitronectin (a protein contained in serum that is known to mediate osteoblast adhesion ((Thomas et al., 1997) see the section Vitronectin ) was responsible for the select, enhanced adhesion (a crucial prerequisite for subsequent, anchorage-dependent-cell function) of osteoblasts on these novel nanoceramic formulations. Specifically, of the proteins (such as albumin, laminin, fibronectin, collagen, and vitronectin) tested, vitronectin adsorbed in the highest concentration on nanophase alumina after 4 hr moreover, competitive adsorption of vitronectin was 10% greater on nanophase compared to conventional alumina (Webster et al.,... 

Early attempts to functionalize biomaterial surfaces with biological molecules were focused on improving blood compatibility of cardiovascular devices, such as the artificial heart and synthetic blood vessels, by immobilizing heparin or albumin on polyurethane or Dacron . To enhance cell adhesion to biomaterial surfaces, entire extracellular matrix (ECM) proteins, such as fibronectin and laminin, have been used directly as coatings. However, because of the nonspecific manner of whole protein adsorption, most of the cell binding capability is often lost. Using a molecular templating technique, it may be possible to select which protein(s) to absorb on biomaterial surfaces. ... 

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