Fig. 4.
PF4 binds to the LDL receptor.
125I-PF4 was incubated for 1 hour at room temperature with soluble human LDL-R (amino acids 1-354). (A) Isotherm of specific binding of 125I-PF4 to sLDL-R. (B) Inhibition of125I-PF4 (0.5 μg/mL) binding to sLDL-R by unlabeled PF4. Data are the mean ± SEM of 3 independent experiments, each performed in triplicate. (C) Isotherm of specific binding of PF4 to sLDL-R detected by the monoclonal antihuman PF4 antibody (RTO). Data are representative of 3 independent experiments, each performed in triplicate.