The role of calcium and RGD in SS-RBC adhesion to TSP. Washed SS-RBCs were incubated with control buffer (None, N = 19), GRGDW (RGD, 200 μmol/L, N = 12), or control peptide GRGEW (RGE, 200 μmol/L, N = 12) for 30 minutes at 37°C before perfusing through flow chambers precoated with TSP. Immobilized TSP was incubated with EDTA (EDTA, 5 mmol/L, 30 minutes, N = 5) or EDTA (5 mmol/L, 30 minutes) followed by 10 mmol/L CaCl₂(EDTA/Ca²⁺ N = 3) before performing the flow adhesion assay as described above.