Clinically obtainable concentrations of clinical-grade heparin inhibit the adhesion of sickle cells to P-selectin.

The number of sickle cells adhering to immobilized protein (A) and the rolling velocities (B) of the adherent sickle cells on immobilized P-selectin were examined in the presence of 0.05, 0.5, 5, or 50 U/mL of laboratory-grade heparin (Sigma) or clinical-grade heparin (Clinical). Adherent sickle cells also were examined for number of cells rolling on BSA (B) or on immobilized P-selectin (P) and their velocities in the absence of heparin.