P-Selectin Expression and Leukocyte-Platelet Binding During the Passage of the Blood Through the Perfusion System
| Experimental Condition . | P-selectin Expression . | Leukocytes With Bound Platelets (% of leukocytes) . |
|---|---|---|
| . | (% of platelets) . | . |
| Untreated blood sample* | 0.5 ± 0.3 | 3.9 ± 3.2 |
| 25 μmol/L TRAP peptide* | 97.7 ± 1.0 | 37.3 ± 7.6 |
| 10 μmol/L ADP* | 38.2 ± 7.8 | 13.1 ± 4.1 |
| Infusion of buffer | 1.7 ± 0.9† | 3.8 ± 1.5 (NS) |
| Infusion of anticoagulant + GPIIb-IIIa antagonist | 1.5 ± 0.7‡ | 6.1 ± 4.8 (NS) |
| Experimental Condition . | P-selectin Expression . | Leukocytes With Bound Platelets (% of leukocytes) . |
|---|---|---|
| . | (% of platelets) . | . |
| Untreated blood sample* | 0.5 ± 0.3 | 3.9 ± 3.2 |
| 25 μmol/L TRAP peptide* | 97.7 ± 1.0 | 37.3 ± 7.6 |
| 10 μmol/L ADP* | 38.2 ± 7.8 | 13.1 ± 4.1 |
| Infusion of buffer | 1.7 ± 0.9† | 3.8 ± 1.5 (NS) |
| Infusion of anticoagulant + GPIIb-IIIa antagonist | 1.5 ± 0.7‡ | 6.1 ± 4.8 (NS) |
Blood was flowing through the entire perfusion system consisting of distribution block, mixing device, and parallel-plate chambers containing noncoated coverslips. Blood samples were taken at the exit of the chambers (see Materials and Methods) and analyzed for P-selectin expression on platelets using an anti-CD62 (P-selectin) and an anti-CD61 (platelets) antibody. Incubation of the blood samples with anti-CD62 (P-selectin) and anti-CD45 (leukocytes) antibodies allowed the identification of leukocytes with bound platelets, which were quantified by dot plot analysis. For comparison, blood samples taken before the blood perfusions, were incubated with a weak (ADP) and a strong (TRAP peptide) platelet agonist to give intermediate and maximal values of P-selectin expression and leukocyte-platelet binding. The results of five experiments, expressed in percentage of total analyzed cells, is presented as the mean ± SD.
Abbreviation: NS, not significant (P > .05).
Blood samples taken before the perfusion.
Comparison with untreated blood sample by paired Student's t-test; P < .05.
Comparison with untreated blood sample by paired Student's t-test; P < .002.