Cell adhesion fibronectin

The leukocyte integrin a 4(3 1 (also known as VLA-4 and CD49d/CD29) is a cell adhesion receptor, which is predominantly expressed on lymphocytes, monocytes and eosinophils. VLA-4 is generally selective for the CS1 domain within fibronectin, with an essential requirement for LDV sequence for binding. VLA-4 also binds to VCAM-1 as a counter receptor. 

FIBRONECTIN IS AN IMPORTANT GLYCOPROTEIN INVOLVED IN CELL ADHESION MIGRATION... 

Nuttelman CR, Mortisen DJ, Henry SM et al (2001) Attachment of fibronectin to poly(vinyl alcohol) hydrogels promotes NIH3T3 cell adhesion, proliferation and migration. J Biomed Mater Res 57 217-223... 

It has been shown that cell adhesion highly depends on the outermost functional groups on SAMs however, cells do not directly interact with the SAMs. Instead, they interact with proteins adsorbed on SAMs. Cell adherence requires an interaction between integral molecules in the cell membrane and glycoproteins specialized for cell adhesion, like fibronectin (Fn) and vitronectin (Vn), which are adsorbed on the artificial material. Thus, the presence of glycoproteins in serum plays a crucial role in cell adherence to artificial materials. In the first part of this review (Sect. 2), we will briefly survey recent studies of cell adhesion on SAMs with different functional groups and discuss the mechanisms involved. 

Aota S, Nomizu M, Yamada KM (1994) The short amino acid sequence Pro-His-Ser-Arg-Asn in human fibronectin enhances cell-adhesive function. J Biol Chem 269 24756-24761... 

Keselowsky BG, Collard DM, Garcia AJ (2003) Surface chemistry modulates fibronectin conformation and directs integrin binding and specificity to control cell adhesion. J Biomed Mater Res 66A 247-259... 

FIGURE 7-1 The immunoglobulin (Ig) gene family of molecules. Several varieties of Ig domain-containing molecules are contained within the Ig gene superfamily. Most are type I membrane proteins some have only Ig domains or other moieties that may convey function (see text). V, variable Ig domain C, constant Ig domain MAG, myelin-associated glycoprotein NCAM, neural cell adhesion molecule GPI, glycosylphosphatidyl-inositol EC, extracellular domain FN, fibronectin. 

The binding of integrins to certain ligands is mediated by a short amino acid sequence. Thus, the binding site for fibronectin is confined to a sequence of four amino acid residues, Arg-Gly-Asp-Ser (RGDS) (R7). Synthetic peptides containing the RGDS sequence prevented adhesion of cells to fibronectin (B4, R7) and also inhibited metastasis formation in animal models (B4, R7). 

One of the most widely studied molecules from this group of adhesion proteins is N-CAM (B4). N-CAM contains type III fibronectin domains in addition to the immunoglobulin domains. N-CAM also forms covalent associations with poly-sialic acid. This modified form of N-CAM may exert a repulsive force through its high negative surface charge. This, in turn, would lessen cell adhesion and allow invasion. 

Figure. 4. Principle of the cell adhesion to artificial materials. In cell culture media or body fluids, the material is spontaneously adsorbed with cell adhesion-mediating extracellular matrix proteins (e g., vitronectin, fibronectin). The cells then adhere to specific amino acid sequences of these proteins by their adhesion receptors of integrin or non-integrin type [38-41].

Cyclic peptide inhibitors of VLA-1 and fibronectin/vascular cell adhesion molecule... 

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. 

Moyano, J. V., Carnemolla, B., Albar, J. P., Leprini, A., Gaggerol, B., Zardi, L., and Garcia-Pardo, A. (1999). Cooperative role for activated a4pl integrin and chondroitin sulfate proteoglycans in cell adhesion to the heparin III domain of fibronectin. ]. Biol. Chem. 274, 135-142. 

All of the oncosphere antigens cloned to date contain either one of two copies of a predicted Fnlll domain. These domains are widely distributed in eukaryotic proteins and occur also in some prokaryotic proteins (Bork and Doolittle, 1992). Approximately 2% of animal proteins include Fnlll domains. Many, but not all, of these proteins are extracellular and some have roles as adhesins. The structure of this 100 amino acid domain is highly conserved and consists of two layers with three p strands in one plane and four p strands in another (Potts and Campbell, 1996). Overall, amino acid sequence identity between different Fnlll domains is low, even between Fnlll repeat domains within fibronectin itself (Plaxco et al., 1997). Nevertheless, certain residues are highly conserved and maintain the tertiary structure of the proteins (Bork and Doolittle, 1992). Other conserved motifs such as an Arg-Gly-Asp (RGD) motif within a loop of some Fnlll domains is associated with proteins having cell adhesion properties, as discussed above (Ruoslahti and Pierschbacher, 1987 D Souza et al., 1991). 

Fig. 13. a Schematic description of the molecules involved in the processes of cell adhesion and migration. Inside the leading edge of the cell, actin filaments (1) are connected via vinculin (2) and talin (4) to integrins, a family of proteins (5) which span the membrane (6). Outside, the integrins have epitopes which normally bind to fibronectin (3) but they can also adhere to artificial surfaces. At the other end of the cell the molecular contacts are broken and the material is recycled, b On artificial surfaces recycling is hindered and cell trails can be observed, c and d Under higher resolution cell trails are seen to be filament like structures or patches... 

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... 

Eisenberg JL, Piper JL, Mrksich M (2009) Using self-assembled monolayers to model cell adhesion to the 9th and 10th type III domains of fibronectin. Langmuir 25(24) 13942-13951... 

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