Simulation and Theory of Antibody Binding to Crowded Antigen-Covered Surfaces
Fig 7
A) plot of the ratio between the stationary concentrations of double-Fab to single-Fab bound ghost antibodies computed from EDBD simulations (symbols). The dashed line is a linear fit performed in the interval 0 < σ < 5 × 10−8 mol/m2. B) plot of the stationary fractions of single-Fab and double-Fab bound antibodies versus antigen concentration (symbols) for the ghost IgG models. In both panels solid lines are fits to the solution of Eq (14). The inset shows a close-up of the low σ region, highlighting the fact that the theoretical predictions N1 ∝ σ, N2 ∝ σ2 (see Eq (11)) at low surface coverage hold unchanged and with similar equilibrium constants and
irrespective of excluded-volume interactions. Best-fit values of the floating parameters are reported in Table 1.
