What's Happening on the Other Side? Revealing Nano-Meter Scale Features of Mammalian Cells on Engineered Textured Tantalum Surfaces.

Advanced engineered surfaces can be used to direct cell behavior. These behaviors are typically characterized using either optical, atomic force, confocal, or electron microscopy; however, most microscopic techniques are generally restricted to observing what's happening on the "top" side or even the interior of the cell. Our group has focused on engineered surfaces typically reserved for microelectronics as potential surfaces to control cell behavior. These devices allow the exploration of novel substrates including titanium, tungsten, and tantalum intermixed with silicon oxide. Furthermore, these devices allow the exploration of the intricate patterning of surface materials and surface geometries i.e., trenches. Here we present two important advancements in our research: (1) the ability to split a fixed cell through the nucleus using an inexpensive three-point bend micro-cleaving technique and image 3D nanometer scale cellular components using high-resolution scanning electron microscopy; and (2) the observation of nanometer projections from the underbelly of a cell as it sits on top of patterned trenches on our devices. This application of a 3-point cleaving technique to visualize the underbelly of the cell is allowing a new understanding of how cells descend into surface cavities and is providing a new insight on cell migration mechanisms.