FIG. 2.

Proliferation rates of primary human renal tubule cells on soft and stiff substrates. (A) Relative proliferation rates based on EdU incorporation for 16 h of subconfluent primary human renal tubule cells on soft (0.5 kPa) and stiff (50 kPa) substrates. (B) Representative fluorescent images showing proliferating cells (red, Alexa Fluor 555 picolyl azide conjugated to incorporated EdU) and total nuclei (blue, DAPI). Subconfluent areas of similar cell densities were chosen for sampling, and number of cells was counted to determine percentages of proliferating cells using ImageJ software. Cells on stiffer substrates appear to be proliferating more rapidly, based on great number of cells incorporating a nucleotide analogue.