... Therefore, interactions of cystatin F with several of its potential targets, cathepsins F, K, V, S, H, X and C, were studiedin vitro. Cystatin F tightly inhibited cathepsins F, K and V with Kivaluesranging ... bufferpH 6.0 with different concentrations of dithiotreitol. After dilution,cystatin F was equilibrated with a twofold molar excess of papain.The residual activity of papain was measured with Z-FR-AMC. ... localization of cystatin F, its restricted and readily regulated expres-sion [18], selective and not too potent inhibition of cathepsins are all in favor of the active role of cystatinF in processes of...