Fig. 2

Stiffness-dependent expression of angiogenic factors in ARPE-19 cells grown on substrates with stiffnesses of 30 kPa, 80 kPa and TCP. (A) Representative WB of CD44 and semiquantitative analysis from n = 4 independent experiments, visualizing normalized expression of CD44 based on GAPDH as the endogenous control, with error bars depicting standard deviation. The full WBs are available in Supplementary Figures S1 and S2 online. (B) Normalized relative expression of VEGF in ARPE-19-CM (n = 4; TCP: n = 3). VEGF levels were normalized to GAPDH concentrations, with media background subtracted. Data are presented as mean relative expression compared to 30 kPa ± SD with individual data points shown. Statistical significance was assessed using one-sample t-tests when comparing normalized values to a hypothetical value of 1.00 (ns: non-significant; *: p < 0.05; **: p < 0.01; ***: p < 0.001).