In vitro assays demonstrating CCL21 cleavage by plasmin. (A and B) Western blot analysis of (A) human and (B) murine CCL21 cleavage after incubation with recombinant plasmin with a fixed molar ratio of 1:0.08 for increasing times at 37°C, as indicated in the figure. (C) Dose titration of the plasmin inhibitor C3 to a fixed molar ratio of murine CCL21:plasmin (1:0.08) and incubation for up to 4 h, as indicated in the figure. Representative western blots of n = 2 (A) or n = 3 (B and C) experiments are shown. (D) Fluorometric plasmin activation assay, with indicated plasmin (12 μM) and inhibitor concentrations. The % increase from T₀ (0 min) is depicted. PIC: broad spectrum protease inhibitor. Representative results of n = 3 independent experiments are shown. Source data are available for this figure: SourceData FS1.