Upside and downside views of adherent cells on patterned substrates: Three-dimensional image reconstruction

Abstract

Understanding cell-material interaction is crucial for tissue engineering, wound healing, and new implant manufacturing. By using microfabricated topographic cues, cell-material interaction can be studied in a more systematical way. Here, we describe a simple technique for three-dimensional image reconstruction of cells on a patterned substrate. Whereas the upside morphology of the cell could be easily obtained by atomic force microscopy (AFM) after cell fixation, the downside morphology of the same cell could be retrieved after reversed cell imprinting. Then, the upside and downside AFM images of the same cell could be matched numerically to achieve a 3D view. We show the results obtained with HeLa and NIH 3T3 cells cultured on patterned substrates made of polydimethylsiloxane (PDMS) of different Young's modules. The penetration of the cell membrane into patterned micro-holes could be analyzed quantitatively, indicating a significant difference between the two cell types as well as between different cell adhesion areas.