Figure 4.

Development of the ECJs of HGKs depended on the substrate roughness in vitro, as shown by confocal laser-scanning microscopy. (A-D) F-actin (green) in HOK-16B cells cultured on the substrates with varying levels of roughness for 5 hours was stained with FITC-phalloidin to identify cortical actin (arrow heads) or lamellipodia (arrows). (E-H) E-cadherin (red) in HOK-16B cells cultured on substrates with varying levels of roughness for 40 hours was immunohistochemically stained to examine how ECJ development depended on the roughness of the substrates. (I-L) E-cadherin (red) of HOK-16B cells cultured on substrates with varying levels of roughness for 4 days were immunohistochemically stained to examine how ECJ development depended on the roughness of the substrates. Intercellular gaps (*) are clearly present between cells in (J) and (K). Refer to the results section for details regarding ECJ development (short bar=20 µm). Ra=121.3±13.4, 505.3±115.3, and 867.0±168.6 nm for R(4000), R(1200), and R(200), respectively.

ECJ: E-cadherin junction, HGK: human gingival keratinocyte, FITC: fluorescein isothiocyanate-labeled, Ra: average roughness, R(4000): prepared with #4000 sandpaper, R(1200): prepared with #1200 sandpaper, R(200): prepared with #200 sandpaper, S: smooth substrate.