Influence of Antimycin A, a bacterial toxin, on human dermal fibroblast cell adhesion to tungsten-silicon oxide nanocomposites

摘要

Nano- and micro-scale engineered surface structures are often used to control cell morphology and mimic the extracellular matrix in tissue engineering. However, there is little understanding of how toxins produced by common bacteria might affect cell adhesion to these structures. In this study, human dermal fibroblast (GM5565) cells were incubated on patterned tungsten/silicon oxide nanocomposite in media in the presence or absence of Antimycin A. This composite consists of parallel tungsten and silicon oxide lines with identical widths in the range of 0.18 and 50 mu m. The morphology of the cells and of their mitochondria was characterized by using high-resolution scanning electron microscopy and fluorescence confocal microscopy. Results show that cells preferentially align along the line axes in a pattern-dependent manner, with a maximum population of cells oriented within 10 degrees of the line axes on the structures containing 10 mu m wide lines. Cells treated with Antimycin A, however, show a smaller proportion of cells oriented in this direction as compared to cells cultured in Antimycin A-free media (34.4% vs 53.0%). The majority of mitochondria in cells growing in Antimycin A-free media are tubular in shape and are preferentially positioned on the tungsten lines, whereas these organelles exhibit a circular geometry and are less attracted to the metal lines in the presence of Antimycin A.