Orientation of ECM protein deposition, fibroblast cytoskeleton, and attachment complex components on silicone microgrooved surfaces

Abstract

The microfilaments and vinculin-containing attachment complexes of rat dermal fibroblasts (RDF) incubated on microtextured surfaces were investigated with confocal laser scanning microscopy (CLSM) and digital image analysis (DIA). In addition, depositions of bovine and endogenous fibronectin and vitronectin were studied. Smooth and microtextured silicone substrata were produced that possessed parallel surface grooves with a groove and ridge width of 2.0, 5.0, and 10.0 microns. The groove depth was approximately 0.5 micron. CLSM and DIA make it possible to visualize and analyze intracellular and extracellular proteins and the underlying surface simultaneously. It was observed that the microfilaments and vinculin aggregates of the RDFs on the 2.0 microns grooved substrata were oriented along the surface grooves after 1, 3, 5, and 7 days of incubation while these proteins were significantly less oriented on the 5.0 and 10.0 microns grooved surfaces. Vinculin was located mainly on the surface ridges on all textured surfaces. In contrast, bovine and endogenous fibronectin and vitronectin were oriented along the surface grooves on all textured surfaces. These proteins did not seem to be hindered by the surface grooves since many groove-spanning filaments were found on all the microgrooved surfaces. In conclusion, it can be said that microtextured surfaces influence the orientation of intracellular and extracellular proteins. Although results corroborate three earlier published hypotheses, they do not justify a specific choice of any one of these hypotheses.

Regulation of implant surface cell adhesion: characterization and quantification of S‐phase primary osteoblast adhesions on biomimetic nanoscale substrates

“…30,31 Indeed, it has been shown experimentally that substrate topography has a direct influence on the composition, orientation, or conformation of adsorbed ECM components. 32 Second, it can be postulated that pits of this scale have an effect on the physical properties of the substrate, affecting surface-free energy, and hence, potential surface wettability. This has been demonstrated to occur on nanofabricated substrates, whereby ordered nanotopography can induce a state of ''superhydrophobicity'' on a material surface.…”

Interactive effects of surface topography and pulsatile electrical field stimulation on orientation and elongation of fibroblasts and cardiomyocytes

“…The non-abraded surfaces (corresponding to the smallest cellular orientation and elongation), were used as a control. Although in vivo, ECM proteins assemble into structures on the order of 10-100nm, the, guidance cues of the structures on the order of μm are well documented [12,39,40]. In the native rat heart, elongated cardiomyocytes are tightly positioned between capillaries (7μm in diameter) that are spaced ∼20μm apart [41], thus structures on the order of 1-10μm have physiological relevance.…”

“…focal adhesions) to an orientation parallel to the groove direction [12,13]. As the ridge size of the grooved surfaces is decreases (to e.g.…”

“…Microstructured grooves were used previously in 2D to direct orientation and elongation of fibroblasts [10][11][12][13]. The process was dependent upon the orientation of actin cytoskeleton [12] that also oriented along the direction of the grooves.…”

“…The process was dependent upon the orientation of actin cytoskeleton [12] that also oriented along the direction of the grooves. Nuclear deformation and elongation was linked to the changes in gene expression on microstructured surfaces [14].…”