For analyses of the capacity of serum to inhibit binding we used 2610 5 tritium-labeled late-stage IE and 15 ml serum in a total volume of 120 ml which were added in triplicates to wells coated with 2 mg/ml of the commercially available chondroitin sulfate proteoglycan Decorin (D8428; Sigma-Aldrich). Decorin was used as a source of CSA as this has a protein core resulting in more efficient coating to plastic than CSA. After incubation for 90 min at 37uC, unbound IE were washed away by resuspension performed by a pipetting robot (Beckman Coulter). The proportion of adhering IE was determined by liquid scintillation counting on a Topcount NXT (Perkin-Elmer).