Fig. 4.

Effect of haem on the angiogenesis of HMEC-1 cells. a, Images of the capillary-like tube formation of HMEC-1 cells stained green (488) after 48 h of culture under different conditions. Under hyperoxic conditions alone, the vascular network was sparse, and the pore size was larger. Upon the addition of 20 μM haem, the vascular network was denser, and the pore size was finer (scale bar = 200 μM). b-d, Quantitative analysis of the number of junctions, length and area of capillary-like tubes formed by HMEC-1 cells. All data are presented as the means ± SD, and the experiment was repeated three times (n = 3). One-way ANOVA or multivariate ANOVA was performed