Fig. 4

Nintedanib inhibits the growth of fibroblasts in response to growth factors produced by fibrocytes. The proliferation of fibroblasts cultured in the cell culture supernatant of fibrocytes with various concentrations of a nintedanib, b BGJ398, c imatinib, and d SU5416 (0–1 μM) was measured by a ³H thymidine incorporation assay. The proliferation of fibroblasts cultured with recombinant growth factors (FGF2: 30 ng/ml, PDGF-AA: 100 ng/ml, PDGF-BB: 100 ng/ml, VEGF-A: 100 ng/ml) for 72 h. 3H–TdR was pulsed for the final 18 h, and the incorporation of 3H–TdR was measured. e Data were analyzed using the Kruskal-Wallis H test and are displayed as median and interquartile range (n = 8–11, independent experiments each). In all graphs: *P < 0.05 versus the value in the group treated with fibrocyte supernatants alone a-d or control e