Figure 4

Gremlin-1 affects the nature, but not the quantity, of mature ECM accumulated by RPTEC. The effect of recombinant human Gremlin-1 on accumulation of mature ECM by RPTEC stimulated with 10 ng/mL TGFβ1. (A) The extent of ECM accumulation was measured via incorporation of ¹⁴C-labelled amino acids. Data show mean ± SD from three independent experiments (individual data points are also shown). ns, not significant; Student’s t-test. (B) Decellularised ECM was fluorescently stained in situ using Flamingo. Images show a single field. (C) Flamingo-labelled ECM images were segmented from the background with analysed region shown in white and branching points within the ECM were analysed using Pipeline Pilot with branches highlighted in unique colours (D) and the number of branches formed in the absence or presence of Gremlin-1 was plotted. Data show mean ± SD from a representative experiment (12 replicates shown as individual data points). ***P < 0.001; Student’s t-test.