Figure 6
Effect of VEGF-cleaving MMPs on the VEGF distribution. Proteases (MMPs) were added to the matrix-sequestered VEGF degradation system at kP = 2.8·10-4 s-1 for systems expressing VEGF121 (C), VEGF165 (D), or VEGF189 (E). We look at the components of the soluble VEGF distribution (i), and bound and total VEGF (ii), both before the addition of proteases (solid lines), and after (dashed lines). The total VEGF distributions of different isoforms, in the presence of proteases (B, black lines), are compared to those in the absence of protease (B, grey lines). Simulations were performed in the absence of receptors (parameters given in Table 4). Isoform fractional gradient values at the tip cell are noted in grey with units %/40 μm.