Fig. 1.

Osmotic pressure regulates the cushion compaction phenotype in vitro. (A) Schematic of experimental design. (B) Compaction (24 h), proliferation (10 h) and cell density (24 h) of HH25 AV cushions cultured in conditioned media. (C) Endpoint bright-field and immunofluorescence images of HH25 AV cushions compacting and rounding over 24 h of hanging drop culture. T, tensile stress; U, unloaded; C, compressive stress. Scale bars: 200 μm in bright-field images; 0.25 μm in immunofluorescence images. n=4-6 cushions per condition from 3-6 independent experiments; data are mean±s.e.m. **P<0.01 (ANOVA with Tukey's post-hoc test).