Osteoblasts attachment

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). 

In another study, Ishaug and co-workers grew enzymatically isolated rat calvarial osteoblasts on different compositions of poly(a-hydroxy ester) films in vitro to evaluate feasibility of cell growth on these polymers and to determine if copolymer composition had any effect on osteoblast adhesion, growth, and phenotype. The compositions tested were 100% PLLA, 75/25 PLGA, 50/50 PLGA, and 100% PGA. Ishaug and co-workers concluded that the osteoblasts attached, proliferated, and maintained their phenotype on all fom compositions. 

Swart, K.M., Keller, J.C., Wightman, J.P. et al. 1992. Short term plasma cleaning treatments enhance in vitro osteoblast attachment to titanium. /. Oral Implant 18 130. 

In addition to in vitro mineralization to evaluate the hone bonding ability of a material, the study of cellular responses to materials intended for use at the bone interface is also important. Using ethyl ethylene phosphate-based polymer (EEP), Wang et al ° investigated cell behavior on a spin-coated P(LLA-Z)-EEP) scaffold. They found that osteoblast attachment and proliferation was significantly enhanced on the PEEP-modified PLEA surface. 

Mouse osteoblasts and fibroblasts were grown on chitosan in the presence of serum. Cell attachment and immunofluorescence analysis were done to analyze phenotypic profiles. Osteoblast attachment at 1 h was significantly greater than that with fibroblasts. At 24 h, levels of cell attachment for fibroblasts increased and became similar to those in osteoblast cultures at 1 and 24 h. Fibroblasts showed... 

Moursi et al. [103] studied the response of osteoblasts to PMMA/HAp materials. They found that osteoblasts attached equally well to PMMA/HAp. In contrast, the increase of osteoblasts on PMMA/HAp was significantly improved, compared to PMMA, after 8 days in culmre. 

Yang YZ, Cavin R, Ong JL. Protein adsorption on titanium surfaces and their effect on osteoblast attachment. J Biomed Mater Res A 2003 67(1) 344—9. 

Du et al. (1998) reported, based on their study of the interaction between osteoblasts (isolated from 4-day-old Wistar rats) and DLC as well as carbon nitride (CN) thin films (obtained by ion beam—assisted deposition (IBAD) technique), that the osteoblasts attach, spread and proliferate on both DLC and CN sample surfaces without apparent impairment of cell physiology. 

P-TCP [23,69]. Furthermore, p-TCP/polyurethane composites showed enhanced osteoblast attachment and proliferation compared to polyurethanes alone [23,71]. 

Optimization of Microdomain Structure to Control Osteoblast Attachment on Poly(ethylene glycol)-Poly(caprolactone) Polyurethanes... 

Biodegradable CS/Gel/HAp composites were prepared by Zhao et al. [262], They obtained similar compositions to that of normal human bone as 3D biomimetic scaffolds by phase separation. By changing the solid content and the compositional variables, the authors controlled the porosities and densities of the scaffolds. Histological and immunohistochemical staining and SEM observations indicated that the osteoblasts attached to and proliferated on the scaffolds. The presence of HAp in the CS/Gel composite promoted initial adhesion of human mesenchymal stem cells (hMSC) and supported long-term growth in 3D porous CS/Gel/HAp scaffolds [263]. 

Smith, 1. A., McCabe, L. R., and Baumann, M. J. 2006. MC3T3-E1 osteoblast attachment and proliferation on porous hydroxyapatite scaffolds fabricated with nanophase powder. International Journal of... 

Peng, H., Xiao, Y., Mao, X. et al. (2009) Amphiphilic triblock copolymers of methoxy-poly(ethyleneglycol)-h-poly(L-lactide)-i>-poly(L-lysine) for enhancement of osteoblast attachment and growth. Biomacromolecules, 10,95-104. 

Gough, J.E., Notingher, L, Bench, L.L., 2004. Osteoblast attachment and mineralized nodule formation on rough and smooth 45S5 bioactive glass monoliths. J. Biomed. Mater. Res. A 68 (4), 640-650. 

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