Figure 2.

Surface structures of HGKs attached to smooth substrates or substrates of low-nanometer dimensions (Ra=121.3±13.4 nm). Cells were processed for observation by FE-SEM 10 hours after cell seeding. (A) Membrane folding and furrows are rich on the surface of the underside of the cell bodies on the rough substrate (bar=5 µm). (B) Membrane folding and furrows gradually fade toward the end of the cell process, which is extended from the cell body on the rough substrate (bar=10 µm). (C) The cells on the smooth substrate display circumferential lamellipodia rich in filopodia (bar=10 µm). (D) Several cell processes extend from the cell body on the rough substrate. Except for the end of the cell processes, the margin of the cell membrane is linear without filopodia. The surface of the cell body is rich in membrane folding and furrows (bar=10 µm).

HGK: human gingival keratinocyte, Ra: average roughness, FE-SEM: field emission scanning electron microscopy.