Abstract. Purified Golgi membranes of the human intestinal adenocarcinoma cell line Caco-2 were used as an antigen to produce a monoclonal antibody, G1/93, which specifically labels a tubulovesicular compartment near the cis side of the Golgi apparatus, including the first cis-cisterna itself, as visualized by single and double immunoelectron microscopy with antibodies against galactosyltransferase. The antigen recognized by G1/93 was identified as a protein with a subunit size of 53 kD. Pulse-chase experiments revealed that the 53-kD protein dimerizes immediately after synthesis followed by formation of oligomers of ~ 310 kD, probably homohexamers. The protein has a transmembrane topology with only a short cytoplasmic segment as assessed by protease protection experiments.

Fibroblasts have been shown to respond to substratum surface roughness. The change in cell size, shape and orientation of rat dermal fibroblasts (RDF) was therefore studied using smooth and microtextured silicone rubber substrata. The microtextured substrata possessed parallel surface microgrooves that ranged in width from 1.0 to 10.0/im, and were separated by ridges of 1.0 to 10.0¿¿m. The grooves were either 0.45 or 1.00^m deep. Prior to incubation, the substrata were cleaned and given a radio frequency glow discharge treatment. After surface evaluation with scanning electron microscopy and confocal laser scanning microscopy, RDF were incubated on these substrata for 5 days. During this period of incubation, the RDF were photographed on days 1, 2, 3, 4, and 5, using phase contrast microscopy. Digital image analysis of these images revealed that on surfaces with a ridge width < 4 .0 ¿tm, cells were highly orientated (<10") and elongated along the surface grooves. H Protrusions contacting the ridges specifically could be seen. If the ridge width was larger than 4.0/tm, cellular orientation was random («45") and the shape of the RDF became more circular. Furthermore, results showed that the ridge width is the most important parameter, since varying the groove width and groove depth did not affect the RDF size, shape, nor the angle of cellular orientation. ((■) 1996 Elsevier Science Limited

No abstract

No abstract

In order to quantify the effect of the substrata surface topography on cellular behaviour, planar and micro-textured silicon substrata were produced and made suitable for cell culture by radio frequency glow discharge treatment. These substrata possessed parallel surface grooves with a groove and ridge width of 2.0 (SÍID02), 5.0 (SÍID05) and 10/¿m (SÍID10). Groove depth was approximately 0 .5 /m Rat dermal fibroblasts (RDFs) were cultured on these substrata and a tissue culture polystyrene control surface for 1, 2, 3, 5 and 7 days. After incubation the cell proliferation was quantified with a Coulter Counter, and RDF size, shape and orientation with digital image analysis. Cell counts proved that neither the presence of the surface grooves nor the dimension of these grooves had an effect on the cell proliferation. However, RDFs on SIID02, and to a lesser extent on SÜD05 substrata, were elongated and aligned parallel to the surface grooves. Orientation of the RDFs on SÍID10 substrata proved to be almost comparable to the SIID00 substrata. Finally, it was observed that the cells on the micro-textured substrata were capable of spanning the surface grooves. © 1996 Elsevier Science Limited Correspondence to E.T. den Braber.Most of the studies are focussed on the role of contact guidance in fundamental organogenesis phenomena like surface implanted biomaterials has only been recognized for last few years. Brunette et a l"'l0, for example, the micro-e implant surfaces to prevent epithelial downgrowth around skin-penetrating devices. Campbell and von Rocum11 described the use of surface micro-patterns as a tool to implantreduce the inflammatory response at tissue interface. Although these studies have provided important information, the fundamental mechanism of, and optimal parameters for, cell control by guidance are still unknown. In addition, the reported results are often based on subjective, qualitative observations. To surpass this lack of knowledge it is evident that a systematic study of the influence of surface topography on the cellular behaviour is required. Therefore, the objective of our studies is to approach this guidance principle in a more orderly way.In our first study12 we reported on the surface treatment on the wettability of surfaces and on 1093