Figure 6. ProAgio and integrin α_vβ₃ interaction is independent of RGD binding.

(a) Apoptosis of HUVEC cells was measured by cell counting 24 h after treatment with 5 μM of ProAgio. The cells were incubated with 5 μM Cilengitide (filled bar) or buffer (open bar) before the ProAgio treatment. Cell apoptosis is presented as % apoptosis by defining the apoptosis of untreated cells as reference 0%. (b) Docking model of ProAgio (Green) with integrin α_vβ₃ in the presence of RGD (Red) using HADDOCK 1.2 program. (c) Levels of α_v (IB: Integrin αV) and β₃ (IB: Integrin β3) integrins in COS-7 cells with expression of β3 (COS7β3) or α_vβ₃ (COS7αVβ3) were analysed by immunoblot of cell lysates. Immunoblot of GAPDH (IB:GAPDH) is a loading control. (d) Cell attachment of COS-7 cells with expression of α_vβ₃ (COS7αVβ3) or β₃ (COS7β3) to culture plate coated with ProAgio. The cell attachments are presented as total number of cells attached to the plate per view field (average of three fields). (e) Apoptosis of COS-7 cells with expression of α_vβ₃ (COS7αVβ3) or β₃ (COS7β3) treated by 5 μM ProAgio. Cell apoptosis is presented as % apoptosis by defining the apoptosis of untreated cells as reference 0%. Error bars in a,d and e are s.d. from measurement of five independent experiments. NS P>0.05, **P<0.005, ***P<0.001 calculated by unpaired two-tailed Student's t-test. NS, not significant.