Figure 3.

Calculated fibril mass at four heparin concentrations based on the proposed model. The value of K_d for the initial tau–heparin complex is the only variable in the calculations. Using the terminology of Knowles and colleagues, values of the remaining constants are k_n = 5 × 10^–4 M^–1 s^–1, k₊ = 8 × 10⁶ M^–1 s^–1. No fibril fragmentation of secondary nucleation (i.e., k₂ = 0) was assumed for simplification.