Fig. 4

Effects of media conditioned by ARPE-19-cells on different cell culture substrates on HUVECs in proliferation, migration and spheroid sprouting assays. (A) MTT-based proliferation assay, representing the average values from five individual experiments (n = 5). The graph depicts the relative absorption compared to 30 kPa after 72 h of incubation. ECGM and unconditioned ARPE-19 medium served as positive (PC) and negative (NC) controls, respectively. (B) Migration assay, depicting data from three separate experiments (n = 3). The graph shows the relative area covered by endothelial cells compared to 30 kPa twelve-hours after seeding. ECGM and unconditioned ARPE-19 medium served as positive (PC) and negative (NC) controls, respectively. (C) Spheroid sprouting assay, integrating data derived from four individual experiments (n = 4). The graph represents the relative cumulative lengths of sprouts compared to 30 kPa, measured 16 h after stimulation. VEGF and unconditioned ARPE-19 medium served as positive (PC) and negative (NC) controls, respectively. Data are presented as mean relative expression compared to 30 kPa ± SD with individual data points shown. Statistical significance in all three angiogenesis assays 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).