Figure 5.

Measurement of FIX activity in the culture medium of cultured liver cells. Isolated hepatocytes and liver sinusoidal endothelial cells were cultured for 16 h in serum-free culture media. Vitamin K₂ was added to the media at increasing concentrations from 0.1 to 10 μg/ml. FIX clotting activity in the media was measured by a one-stage clotting assay (n=6, respectively). Data were expressed as the percentage of normal mouse plasma. Values were represented as mean±SEM. Hep, hepatocytes; LSECs, liver sinusoidal endothelial cells; N.C., cell-free control media. Asterisks indicate significant differences versus N.C.