TABLE 2.
Calculated Ki values for Proteins and Peptides that Compete for Factor XIa Binding to the Activated Platelet Surface
| Competitor | Ki (10−9 M) |
|---|---|
| FXIa | 1.4 ± 0.28 |
| FXI | NE |
| rFXIa/PKA3 | 2.7 ± 0.32 |
| rFXI/PKA3 | NE |
| TRP383-LEU397 (peptide 1) | NE |
| PHE415-GLY429 (peptide 2) | NE |
| GLN433-GLU447 (peptide 3) | NE |
| ILE450-ALA446 (peptide 4) | ND |
| LYS467-ILE481 (peptide 5) | NE |
| GLY500-LEU514 (peptide 6) | NE |
| CYS527-CYS542 (peptide 7)* | 5.8 ± 0.78 |
| CYS527-CYS542 (peptide 8)*† scr | NE |
| Heavy Chain | NE |
| Catalytic Domain | 3.5 ± 0.42 |
*
Denotes a cyclized peptide
†
scr denotes scrambled peptide
NE denotes no effect of the ligand at concentrations of up to 200 nM for FXI and rFXI/PKA3, up to 1 μM for the heavy chain, 100 μM for peptides 1–3, 5–6, and 1 μM for peptide 8.
ND denotes a value that was not determined.
Values represent the mean ± standard deviation for three independently performed experiments each carried out in triplicate.