Sickle and normal RBC adherence to immobilized TSP. (A) Glass slides were coated with varying concentrations of TSP (2.5 to 100 μg/mL) and adhesion of normal and sickle RBC assessed under flow conditions as described in Fig 1. Error bars are standard deviation (SD) of 10 randomly chosen microscopic fields from one representative experiment. (B) Slides were coated with TSP (50 μg/mL) or BSA as described in Materials and Methods. In some experiments, the slides were additionally treated with EDTA (5 mmol/L) or a 1:2 dilution of a rabbit polyclonal anti-TSP antiserum (R1)34 before RBC perfusion. Error bars are SEM.