Fig. 4

Proliferation of iPericytes through the PDGF-BB: PDGFRβ signalling pathway. A iPericytes were incubated in basal pericyte media (PM) and treated with PDGF-BB (PM + PDGF-BB) while being exposed to 100 µM imatinib (PM + PDGF-BB + 100 µM imatinib). Proliferation was measured using an EdU uptake assay. iPericytes that are EdU-positive are indicated by magenta, while total number of iPericytes were measured by DAPI (blue). Scale bar = 50 µm. B Quantification of HBVPs, neural crest iPericytes and mesoderm iPericytes proliferating (as indicated by EdU-positive staining) as a percentage of total cells following 24 h exposure to PM, complete pericyte media with pericyte growth factors (CPM) or PM + PDGF-BB (n = 8 per condition). Data were analysed using a one-way ANOVA: HBVP (F (2, 21) = 35.52, p < 0.0001); neural crest iPericyte (F (2, 21) = 30.85, p < 0.0001); mesoderm iPericyte (F (2, 21) = 191.4, p < 0.0001). C Quantification of changes to PDGF-BB-induced proliferation with increasing concentrations of imatinib over 24 h in HBVPs, neural crest iPericytes and mesoderm iPericytes (n = 8 per condition). Data were analysed using a one-way ANOVA or Kruskal–Wallis test: HBVP (F (3, 26) = 259.2, p < 0.0001); neural crest iPericyte (H (3) = 24.41, p < 0.0001); mesoderm iPericyte (F (3, 28) = 221.5, p < 0.0001). For B, C, post-hoc comparisons were performed using Dunnett’s multiple comparisons or Dunn’s test: *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. Data shown as mean ± SD. D Heat map of key genes involved in pericyte proliferation in the PDGF-BB: PDGFRβ signalling pathway in HBVP, neural crest iPericytes and mesoderm iPericytes selected from Sweeney et al. [29]