High Throughput Techniques for the Investigation of Cell–Material Interactions - Biointerfaces: Where Material Meets Biology - page 261

biosensors and tissue engineering, just to name a few. 24 Distinct types of cell
have different demands in that the surface characteristics required for
successful cellular response will vary between cell types. For example Kun-
zler et al. 25 found that fibroblasts showed preferential attachment towards
smooth surfaces whereas osteoblasts favoured rougher surfaces.
The properties of a given surface have long been known to affect responses
such as the attachment and proliferation of cells. Surface characteristics
including wettability, topography, chemical functionalities, biomolecule
density and elasticity have been identified as critical parameters
(Figure 10.1). 5,9,11 In many instances, it is the adsorbed biomolecules on the
surface, usually originating from serum, which have the greatest influence
on cellular response. 26 Therefore, the composition of this protein layer re-
quires considerable attention when aiming at tailoring the surface for an
optimum cellular response. For this reason, researchers have invested sig-
nificant research into methods of either preventing protein adsorption or
conversely the immobilisation of proteins (or parts thereof) to a surface to
help direct a cellular response. 1,11,27
The extracellular matrix (ECM) is the extracellular part of tissues that
provides structural support to cells. Besides structural support, the ECM
performs many other functions including assistance with anchorage of cells,
segregation of tissues from one another and regulating intercellular com-
munication. The ECM is composed of many different proteins, the most
commonly known include collagen, vitronectin, Fn, elastin and laminin. All
of these proteins are involved in the attachment of cells through interacting
with integrin receptors present on the cell surface. 28,29 Thus, the ability to
control the presentation of ECM proteins on a substrate is a promising ap-
proach towards the tailoring of implant devices and other biomaterials. For
this reason, considerable attention has been directed towards cell-surface
interactions on ECM modified substrates. 30-34 Subunits of ECM proteins

d n 3 r 4 n g | 7

.

Figure 10.1 Schematic demonstrating the wide variety of material surface character-

istics that influence cellular response with regards to attachment,
proliferation, self-renewal or differentiation.