Cell adhesion and proliferation

At a low concentration, PLL promotes cell adhesion and proliferation, in particular for the serum medium. The promotive effect of PLL may be due to the electrostatic attraction between the positively charged polymers and the negatively charged cells. When being adsorbed by the culture plate surface. 

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Schiraldi et al. [64] have developed this kind of material by combining silica particles and pHEMA. pHEMA is a biocompatible hydrogel that has been widely studied in the past decades due to its chemical-physical structure and mechanical properties. It has been widely used in ophthalmic prostheses (contact or intraocular lenses), vascular prostheses, drug delivery systems and soft-tissue replacement [65]. These authors have shown that by incorporating silica nanoparticles, the resulting hybrid material is highly biocompatible and promotes bone cell adhesion and proliferation of bone cells seeded on it.1 ... 

Schiraldi, C., DAgostino, A., Oliva, A., Flamma, F., De Rosa, A., Apicella, A., Aversa, R. and De Rosa, M. (2004) Development of hybrid materials based on hydroxyethylmethacrylate as supports for improving cell adhesion and proliferation. Biomaterials, 23, 3645-3653. 

We investigated the efficiency of NSC expansion on surfaces with EGF-His immobilized in the correct orientation. NSCs were obtained from neurosphere cultures prepared from fetal rat striatum harvested on embryonic day 16. NSCs were cultured for 5 days on EGF-His-immobilized substrates prepared with mixed SAMs of different COOH-thiol contents. Cells adhered and formed network structures at a density that increased with the COOH-thiol content of the surface. As a control, cells were seeded onto surfaces without immobilized EGF-His. This resulted in poor cell adhesion during the entire culture period. In addition, when EGF-His adsorbed to SAMs with 100% COOH-thiol or SAMs with NTA-derivatized COOH that lacked Ni2+ chelation, we observed poor initial cell adhesion, and the cells formed aggregates within 5 days. Interestingly, the substrate used to covalently immobilize EGF-His with the standard carbodiimide chemistry was not a suitable surface for cell adhesion and proliferation. The control experimental results contrasted markedly with results from EGF-His-chelated surfaces. 

In order to achieve the firm fixation of the artificial cornea to host tissues, composites of collagen-immobilized poly(vinyl alcohol) hydrogel with hydroxyapatite were synthesized by a hydroxyapatite particles kneading method. The preparation method, characterization, and the results of corneal cell adhesion and proliferation on the composite material were studied. PVA-COL-HAp composites were successfully synthesized. A micro-porous structure of the PVA-COL-HAp could be introduced by hydrochloric acid treatment and the porosity could be controlled by the pH of the hydrochloric acid solution, the treatment time, and the crystallinity of the HAp particles. Chick embryonic keratocyto-like cells were well attached and proliferated on the PVA-COL-HAp composites. This material showed potential for keratoprosthesis application. Further study such as a long-term animal study is now required [241]. 

Modified PTFE surfaces show a high degree of biocompatibility with good cell adhesion and proliferation [7-11], However, the UV-treatment results also in a loss of mechanical stability due to the scission of polymer chains, especially for light-sources with wavelengths below 193 nm [6], Similarly to the ion implantation or plasma modification, also the UV light-irradiation is performed on both sides of a polymer foils in order to avoid the material torsion. 

On the other hand, the principle of CellCube and Cell Factory is to provide a large area for cell adhesion and proliferation in relatively compact devices. The latter consists of multiple trays, providing surface areas in the range of 700-25 000 cm2, for medium volumes of 0.2-8 L (Nunc, 2006). The system called CellCube provides a surface area in the range of 8500-85 000 cm2 and is fitted with an automated control system (Corning, 2006). 

Polyurethanes have been widely applied as matrix (wall) materials of synthetic vascular grafts. With the purpose of endothelialization, the main goal of surface modification is to enhance EC affinity for both cell adhesion and proliferation. In this study, MPEO-derived SMAs are enrolled to... 

To mimic the macromolecular-based ECM in biological tissue, the cell adhesion and proliferation properties of hydrogels are critical parameters. However, various hydrogels that originate from natural resources, such as alginate [87], chitosan [88, 89], and hyaluronic acid [90], and that are synthetically created, such as poly (7V-isopropylacrylamide) (PNIPAAm) [91], PEO [92], PVA [93], and poly(ethylene glycol) (PEG) [94], show a poor cellular viability without modification with cell adhesive proteins or peptides, such as collagen, laminin, fibronectin, and the RGD (Arg-Gly-Asp) sequence. 

Human endothelial cells isolated from umbilical cord (HUVECs) were seeded on pure and RGD modified gels to determine the cell-adhesive characteristics of the compared materials. Cell adhesion and proliferation (or apoptosis) were observed by means of microscopic and colorimetric techniques. 

Gotze T, Valtink M, Nitschke M et al (2008) Cultivation of an immortalized human corneal endothelial cell population and two distinct clonal subpopulations on thermo-responsive carriers. Graefes Arch Clin Exp Ophthalmol 246 1575-1583 Gramm S, Komber H, Schmaljohann D (2005) Copolymerization kinetics of N-isopropylacryla-mide and diethylene glycol monomethylether monomethacrylate determined by online NMR spectroscopy. J Polym Sci Pol Chem 43 142-148 Hatakeyama H, Kikuchi A, Yamato M et al (2006) Bio-functionalized thermoresponsive interfaces facilitating cell adhesion and proliferation. Biomaterials 27 5069-5078... 

Another study in this direction was performed by Qiatelet et al. [72]. They investigated the effect of DD on the biological properties of chitosan films by culturing keratinocytes and fibroblasts on chitosan films having different DDs. They found that DD has no significant effect on the in vitro cytocompatibility of chitosan films towards keratinocytes and fibroblasts. They demonstrated that the lower the DD of chitosan, the lower was the cell adhesion on the films, and found that keratinocyte proliferation increases when the DD of chitosan films increases. They concluded from their study that the DD plays a key role in cell adhesion and proliferation, but does not change the cytocompatibility of chitosan. 

Luna SM, Silva SS, Gomez ME, Mano JF, Reis RL (2010) Cell adhesion and proliferation onto chitosan-based membranes treated by plasma surface modification. J Biomater Appl (in press) doi 10.1177/0885328210362924... 

PLLA, PLGA, PGA Nonwoven scaffold TE SEM, ESCA, in vitro fibroblast culture, cell adhesion, and proliferation assay (Park et al. 2007)... 

Hydrophobicity of biomedical polymers influences the biocompatibility depending on the particular application such as tissue engineering, blood contacting devices, and dental implants [35]. Polymers are dynamic structures and can switch their surface functional groups depending on the environment. For example, polymeric biomaterials need to have a hydrophilic smface for most of the applications, so that the cell-adhesive proteins present in the serum will be adsorb and promote cell adhesion and proliferation. This is achieved by snrface treatment procedures such as... 

Einally, linear amphiphilic PEG-Z)-PLLA-Z)-PLL triblock copolymers were synthesized and blended with PLLA for film formation. Investigation of the film surface revealed an enrichment of PLL blocks on the surface of the PLLA film. Human osteoblast tests performed on different PLLA films showed that the triblock copolymers were much more effective in promoting cell adhesion and proliferation compared to the PEG-6-PLLA diblock-modified and virgin PLLA films. The self-segregation of the PEG-6-PLLA-A-PLL triblock copolymers on the film surface demonstrated a potential application in the preparation of functional scaffolds for tissue engineering. 

The cationic PAAm-modified surface supports cell adhesion, proliferation and chondrogenic differentiation. The cell-culture polystyrene surfaces support cell adhesion and proliferation, but not chondrogenic differentiation. 

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