Plasma VWF levels determine platelet deposition on laminin and VWF coatings. (A) VWF concentration of WT or Tlr2^−/− platelet lysates after incubation with the indicated plasmas (5 mice per group). (B) Static laminin deposition of Rhodamin B–stained, washed WT and Tlr2^−/− platelets (red) after 30 minutes of preincubation with WT (Vwf^+/+) or Vwf^+/− plasma. Representative images (left) and quantification (right); quadruplicate determination (3 mice per group). Representative images are shown. (C) Laminin adhesion of washed Tlr2^−/− platelets supplemented with 51 mIU/mL of human VWF (Wilfactin) in the absence or presence of anti-VWF LJ-152B-6 (α-RGD) directed against the RGD motif; quadruplicate determination (3 mice per group). (D) Deposition of washed platelets from WT, Tlr2^−/−, or Vwf^−/− mice preincubated for 30 minutes with the indicated plasma sources on human VWF coatings. Anti-VWF LJ-152B-6 (α-RGD) was added where indicated. Quadruplicate determination (3 mice per group). Scale bar, 100 µm; mean ± SEM; independent-sample Student t tests or ANOVA with Tukey post hoc test or Kruskal-Wallis test, *P < .05. n.s., not significant.