Cell-material interactions

Material surface characteristics are important for cell—material surface interactions. Three types of cell—material surface interactions can be defined, as illustrated in Fig. 7.1, which is based on the concept proposed in Ref. 76. The first one is nonfouling interactions, in which case cells fail to interact with the material surface. This type of interaction is preferred for various biomedical applications such as artificial blood vessels and valves, artificial heart devices, catheters and blood preservation bags. The second type of interactions is passive adhesion, in which case interfacial response is controlled by physicochemical interactions between the material surface, adsorbed proteins and adhering cells. Surfaces in this category inhibit cellular metabolic changes. The adherent cells remain intact and are readily detached from these surfaces with little damage. The third is bioactive cell adhesion, in which cells activate 

Thin Film Coatings for Biomaterials and Biomedical Applications 

Bacterial infection also represents a serious complication for various biomedical implants. Therefore, when discussing cell—material interactions, both mammalian cell—material interactions and bacterial—material interactions should be included. 

The nonadsorptive nature of these materials allows for their modification in order to include specified biological signals. Cells will not adhere to hydrogels without chemical or biological modification of the material. While it may seem that lack of cell adhesion to materials intended for tissue engineering applications would not be a desirable property, this is not necessarily the case. This anti-adhesive property is beneficial, as it allows precise, defined modifications of the material to achieve a specific cellular response without interference by nonspecific cell or protein interactions. 

Poly (ethylene glycol) (PEG) has been used to not only ereate scaffolds, but also to improve the material or molecule hydrophihcity and inhibit protein adsorption on a variety of materials (Elbert and Hubbell, 1996 Tirrell et al., 2002). Hydrogels consisting of PEG may be synthesized by modifieation of PEG to contain photopolymerizable acrylate groups, whose crosslinking to form a hydrogel is initiated by radical formation and propagation. In particular, photopolymerization has been exploited to 

The ability of hydrophilic polymers, specifically PEG, to provide a substrate material that is essentially a blank slate is extremely valuable in both investigations of the nature of cell-substrate interactions as well as in the creation of well-defined biomaterials and tissue engineering scaflblds. In this marmer, PEG serves as an ideal material which can be modified to contain numerous biological signals. 

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After a masterful introduction of the field and its new directions by Michael Sefton of the University of Toronto, Kristi Anseth of the University of Colorado offers a critical analysis of cell-materials interaction problems with emphasis on the nature of cell adhesions, adhesion ligands, and surface chemistry. 

Exploitation of our knowledge of cell-material interactions can allow the bioengineer to rationally design appropriate materials for applications such as tissue engineering. 

Kristi S. Anseth and Kristyn S. Masters, Cell-Material Interactions... 

Cell Culture as an Advantageous Evaluation System for Cell-Material Interaction... 

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). 

K. M.C., and Lu, W.W. (2007) Preparation and cell-materials interaction of plasma sprayed strontium-containing hydroxyapatite coating. Surf. Coat. Technol., 201, 4685 -4693. 

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