Effect of Proteinase Inhibitors on LPS-, TNF-–, and IL-8–Mediated Downmodulation of CXCR1 and CXCR2 Expression
| Inhibitor . | % Inhibition of Downmodulation*,† . | |||||
|---|---|---|---|---|---|---|
| CXCR1 . | CXCR2 . | |||||
| +LPS . | +TNF-α . | +IL-8 . | +LPS . | +TNF-α . | +IL-8 . | |
| 1,10-Phenanthroline† | 92.8 ± 3.5 | 87.1 ± 0.7 | −2.1 ± 2.5 | 89.0 ± 8.3 | 70.8 ± 7.5 | 1.2 ± 1.7 |
| EDTA | 94.9 ± 4.0 | 92.3 ± 1.5 | 9.1 ± 7.0 | 75.1 ± 2.7 | 80.8 ± 8.0 | 4.7 ± 5.2 |
| EGTA | 43.9 ± 5.7 | 30.5 ± 5.0 | 4.4 ± 1.7 | 27.7 ± 2.8 | 27.9 ± 5.1 | 1.1 ± 0.8 |
| 3,4-Dichloroisocoumarin | 48.2 ± 20.2 | 50.8 ± 5.9 | −11.2 ± 10.3 | 24.3 ± 10.8 | 32.7 ± 3.9 | −11.6 ± 1.0 |
| TLCK | 41.2 ± 3.9 | 41.6 ± 6.8 | 17.8 ± 4.7 | 26.5 ± 7.1 | 33.7 ± 7.0 | 16.5 ± 5.5 |
| Leupeptin | −2.9 ± 1.6 | −3.0 ± 1.2 | −2.5 ± 1.7 | −1.3 ± 0.6 | −0.9 ± 0.4 | −1.6 ± 1.3 |
| Aprotinin | −2.1 ± 1.6 | −3.8 ± 1.0 | −3.2 ± 0.6 | −4.1 ± 3.1 | −2.7 ± 1.3 | −1.7 ± 1.1 |
| α1-Antitrypsin | −4.2 ± 0.7 | −3.1 ± 1.4 | −3.3 ± 1.2 | −3.5 ± 1.5 | −4.6 ± 1.3 | −3.4 ± 3.5 |
| Bestatin | −2.0 ± 6.8 | −10.9 ± 5.4 | −28.2 ± 8.2 | 2.4 ± 13.3 | −0.3 ± 6.0 | −16.7 ± 7.1 |
| Pepstatin A | 2.7 ± 2.1 | 9.6 ± 3.1 | −24.3 ± 6.4 | 1.8 ± 3.2 | 3.1 ± 1.2 | −14.3 ± 5.1 |
| Phosphoramidon | −2.2 ± 1.2 | −15.1 ± 7.9 | 7.2 ± 2.8 | 3.7 ± 4.5 | 7.3 ± 3.0 | 5.8 ± 1.2 |
| Inhibitor . | % Inhibition of Downmodulation*,† . | |||||
|---|---|---|---|---|---|---|
| CXCR1 . | CXCR2 . | |||||
| +LPS . | +TNF-α . | +IL-8 . | +LPS . | +TNF-α . | +IL-8 . | |
| 1,10-Phenanthroline† | 92.8 ± 3.5 | 87.1 ± 0.7 | −2.1 ± 2.5 | 89.0 ± 8.3 | 70.8 ± 7.5 | 1.2 ± 1.7 |
| EDTA | 94.9 ± 4.0 | 92.3 ± 1.5 | 9.1 ± 7.0 | 75.1 ± 2.7 | 80.8 ± 8.0 | 4.7 ± 5.2 |
| EGTA | 43.9 ± 5.7 | 30.5 ± 5.0 | 4.4 ± 1.7 | 27.7 ± 2.8 | 27.9 ± 5.1 | 1.1 ± 0.8 |
| 3,4-Dichloroisocoumarin | 48.2 ± 20.2 | 50.8 ± 5.9 | −11.2 ± 10.3 | 24.3 ± 10.8 | 32.7 ± 3.9 | −11.6 ± 1.0 |
| TLCK | 41.2 ± 3.9 | 41.6 ± 6.8 | 17.8 ± 4.7 | 26.5 ± 7.1 | 33.7 ± 7.0 | 16.5 ± 5.5 |
| Leupeptin | −2.9 ± 1.6 | −3.0 ± 1.2 | −2.5 ± 1.7 | −1.3 ± 0.6 | −0.9 ± 0.4 | −1.6 ± 1.3 |
| Aprotinin | −2.1 ± 1.6 | −3.8 ± 1.0 | −3.2 ± 0.6 | −4.1 ± 3.1 | −2.7 ± 1.3 | −1.7 ± 1.1 |
| α1-Antitrypsin | −4.2 ± 0.7 | −3.1 ± 1.4 | −3.3 ± 1.2 | −3.5 ± 1.5 | −4.6 ± 1.3 | −3.4 ± 3.5 |
| Bestatin | −2.0 ± 6.8 | −10.9 ± 5.4 | −28.2 ± 8.2 | 2.4 ± 13.3 | −0.3 ± 6.0 | −16.7 ± 7.1 |
| Pepstatin A | 2.7 ± 2.1 | 9.6 ± 3.1 | −24.3 ± 6.4 | 1.8 ± 3.2 | 3.1 ± 1.2 | −14.3 ± 5.1 |
| Phosphoramidon | −2.2 ± 1.2 | −15.1 ± 7.9 | 7.2 ± 2.8 | 3.7 ± 4.5 | 7.3 ± 3.0 | 5.8 ± 1.2 |
Cell surface expression of CXCR1 and CXCR2 was measured using FACScan analysis.
Neutrophils were pretreated for 30 minutes at 37°C with the following concentrations of inhibitors: 1,10-phenanthroline (0.5 mmol/L), EDTA (5 mmol/L), EGTA (5 mmol/L), 3,4-dichloroisocoumarin (100 μmol/L), TLCK (200 μg/mL), leupeptin (100 μmol/L), aprotinin 1:100 U/mL, α1-antitrypsin (100 μg/mL), bestatin (100 μmol/L), pepstatin A (1 μg/mL), and phosphoramidon (100 μmol/L).
Mean ± SEM of n = 3 experiments.