FIGURE 2.

Interference with GAG biosynthesis decreases accumulation of FXIIa on the cell surface. A and B, HLF were treated with 2.5, 5, or 10 μm β-d-xyloside (A) or 50, 100, or 200 ng/ml tunicamycin (B) for 2, 3, or 4 days to prevent initiation of GAG synthesis or to inhibit N-linked glycosylation, respectively. Following the FXIIa treatment, accumulation of FXIIa on the cell surface was assessed by cell-based ELISA, and resulting values are given as a percentage of FXIIa binding to β-d-xyloside- or tunicamycin-untreated cells (set as 100%) (n = 4); #, p < 0.05; ##, p < 0.01; ###, p < 0.001 versus FXIIa only. C and D, cell damage caused by 4-day-long incubation of HLF with 10 μm β-d-xyloside or 200 ng/ml tunicamycin as assessed by release of lactate dehydrogenase (LDH) into cell culture media (C) or by microscopic inspection of the cells (D). The data are representative of three independent experiments. Magnification was ×100. Data represent mean ± S.D. (error bars).