Influence of systematically varied nanoscale topography on the morphology of epithelial cells.

With the knowledge that cells can react to lithographically manufactured nanometer-sized surface objects, our interest concerned whether cells would respond to surface structures of systematically increasing size. Our approach to answer this question was to fabricate surfaces with the same surface chemistry and similar surface roughness but increasing size of structural features. To fabricate large areas of patterned surfaces, required for cell culture studies, we used colloidal lithography utilizing colloidal particles as a template for surface nanostructuring. The fabricated surfaces contained hemispherical nanopillars with diameters ranging from 60 to 170 nm. Changes in cell morphology of a pancreatic epithelial cell line (AR4-2J) were studied by evaluating cell area and cell shape. The latter was studied by applying the cell shape classification method using three shape descriptors. The pancreatic cells responded in a systematic way to the surface nanostructures. The cells spread more and became more nonround when cultured on surfaces with increasing size of the topographic features. Index Terms-Biological cells, image analysis, nanotechnology, shape measurement, surfaces.