TABLE 1.
Inhibition of 32P-sCD14 binding to PGN-agarose and LPS-agarose by sCD14 deletion mutantsa
| Inhibitor | IC50 (μg/ml) of:
|
|||
|---|---|---|---|---|
| PGN-agarose
|
LPS-agarose
|
|||
| No LBP | + LBP | No LBP | + LBP | |
| sCD14 (wt) | 8.2 ± 1.9 | 5.5 ± 0.9 | 56.1 ± 12 | 0.66 ± 0.2 |
| DDED | 6.3 ± 0.2 | 4.9 ± 0.9 | 48.3 ± 8.6 | 11.2 ± 3.7 |
| PQPD | 14.9 ± 3.2 | 15.8 ± 0.7 | >300 | 34.6 ± 5.7 |
| DDED + PQPD | 9.0 ± 2.6 | 17.4 ± 4.0 | >300 | 188 ± 55 |
| DPRQY | 33.4 ± 7.2 | 32.9 ± 5.0 | enhanced 4.7×b | enhanced 1.5×b |
| AVEVE | 43.6 ± 13 | 70.3 ± 21 | enhanced 1.9×b | >1,000 |
| QUAD | >1,000 | >1,000 | >1,000 | >1,000 |
a
Inhibition of binding of 32P-sCD14 to PGN-agarose and LPS-agarose by various concentrations of the indicated unlabeled sCD14 wt or deletion mutants, with or without 1 μg of LBP/ml, was measured, and the IC50 was calculated based on a logarithmic curve fit. The results are means of three experiments ± SE.
b
Binding of 32P-sCD14 to LPS-agarose was increased with the addition of some unlabeled sCD14 deletion mutants. The maximum fold enhancement, which was seen at 20 μg/ml, is shown.