Figure 4.
Mast cells and endothelial cells associate during the tube formation assay. (A,B) SVEC4-10 cells; (C,D) SVEC4-10 cells co-cultured with P815 mast cells. (A,B) In cell cultures without mast cells, the endothelial cells form only incomplete loops (arrowheads); (C,D) During co-culture SVEC4-10 endothelial cells (arrowheads) and mast cells (arrows) are associated especially in the loops (L). The endothelial cells are spread on the substrate (arrowheads) while P815 mast cells remain rounded (arrows). Cells were cultured for 5 h prior to assay. Scanning electron microscopy images are representative of four independent experiments.