Proliferation Assay (Promega). Data shown represent mean 6 s.e.m. and are derived from 3 independent cell isolations, each prepared from multiple litters of embryos and 4 replicates of each treatment (n = 12). ** P,0.01, ***P,0.001. (TIF) Figure S4 FGF2 promotes migration of primary mouse LEC in a dose dependent manner. Confluent monolayers of primary LEC were scratched and cultured in EBM+0.5% FBS containing FGF2 at the indicated concentrations. The area of LEC migration was quantified after 8 h. Data represent mean 6 s.e.m. of three independent scratches using one cell isolation prepared from multiple litters of embryos (n = 3). (TIF) Figure S5 FGF receptor profile in primary LEC and BEC isolated from adult mouse skin. (a) Real-time RT- PCR analysis of Fgfr1-4 mRNA levels in LEC and BEC freshly isolated from adult ear skin. Data are normalised to Actb and show mean 6 s.d. of triplicate samples from one experiment. 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