TLT-1 copy number and interaction with fibrinogen. (A) Measurement of TLT-1 copy number on resting and ADP-activated platelets (n = 3). (B) Quantification of panel A. (C) Plate bound binding curve of sTLT-1 interaction with fibrinogen predicting a K_d of 53 nM. (D) Confocal images of fibrinogen staining in the lung 24 hours after intranasal LPS treatment. Lungs from WT, treml1^−/−, or treml1^−/− mice treated with sTLT-1 were stained with fibrinogen (red) and 4′,6-diamidino-2-phenylindole (blue), demonstrating that sTLT-1 increases fibrinogen deposition in the lung. Side panel: quantification of the staining on the left (n = 5 mice per group, 5 slides per lung; **P ≤ .01, ***P ≤ .001). The red line equals 100 μM.