Fig. 3.

Left: mechanical equilibrium of the interfacial tensions in the radial direction of the adhering shell. The contact line L_c marks the transition between the adhering and non-adhering zones. The contact tension σ₁₂ and σ₁₃ are measures of the interfacial energies between the supported membrane and the vesicle surface and the aqueous phase, respectively. σ₂₃ = σ is the surface tension of the vesicle. Middle: independent measurement of σ, κ and the free adhesion energies of adhering Dictyostelium cell by contour analysis in the presence and absence of a hydrodynamic flow field. Right: RICM image in the absence (left) and presence (right) of a hydrodynamic flow field. Image adopted from ref. 4. The adhesion strength could be extracted following the discussion in the Appendix of ref. 43.