Micropillar substrate influences the cellular attachment and laminin expression.

Fibroblasts alter their mode of attachment and focal contact when placed on square arrays of silicon pillars. The pillars had 1-microm diameters with identical surface chemistry. Distance between pillars is 9 microm and height of pillars is 1, 5, or 10 microm on substrates. We found that these micropillars, rather than specific interactions, provided more opportunities for mechanical interlocking of the fibroblasts and acted as physical barriers that restrained cell migration. The cellular morphology and behavior is guidable by the height of pillars. In some cases, the fibroblasts filled in the intervals among several pillars; in others, a pillar protruded visibly through the cell body but did not pierce it, the cells were survived. Therefore, fibroblasts were immobilized upon in situ and the cytoplasma migrated outward to the bottom of the substrate subsequently. Laminin plays a critical role in cell attachment to the basement membrane. The results of laminin expression in fibroblasts suggest that pillar pattern appears to change cellular behavior and affect laminin expression significantly.