Figure 3
From: Human endothelial cells secrete neurotropic factors to direct axonal growth of peripheral nerves
Neurotrophic factors secreted by HUVECs enhance axonal growth from DRG explants. Seven factors that were secreted by HUVECs and underexpressed in HUVEC-DRG co-cultures were selected from the results of the cytokine array. DRGs were cultured on PDL coated wells in either EGM-2 or DMEM medium supplemented with 0, 5, 50, or 100 µg/mL of BDNF, GDNF, VEGF, IL7, OPN, PDGF-ββ, FGF4, or MIF for 4 days. All concentrations of BDNF and GDNF significantly enhanced axonal outgrowth. Axonal outgrowth was not affected by the concentration of the remaining growth factors, although there were some treatment groups, such as IL7, that displayed significantly higher axonal outgrowth when cultured in EGM-2 rather than DMEM. Data are presented as mean ± standard error. †(p < 0.05), ††(p < 0.01), †††(p < 0.001) indicates significance from EGM-2 medium by two-tailed Student’s t-test; *(p < 0.05), **(p < 0.01), ***(p < 0.001) and brackets indicate significance from indicated treatments as determined by one-way ANOVA with Holm-Sidak post hoc analysis (DRG sample size for each group shown in bars from 2 independent replicates). Comparisons of all other growth factors to controls were not significant (ANOVA).
