FIG. 7.

Influence of SP-C(LKS) on the interaction between ¹²⁵I-labeled CD14 and LPS. Polystyrene plates were coated with LPS by incubation (18 h, 37°C) with suspensions (150 μl) of the S. enterica serovar Minnesota Re595 LPS (20 μg/ml in Tris buffer [pH 9.6]). The plastic surface was then saturated with BSA (1 mg/ml, 1 h, 37°C) and washed. A solution (100 μl) of ¹²⁵I-CD14 (30,000 cpm in 0.15 M NaCl containing 600 μg of BSA per ml), alone or preincubated (2 h, 20°C) with various concentrations of SP-C(LKS), was added to uncoated or LPS-coated wells. After the wells were incubated for 2 h at 20°C and washed five times, the bound radioactivity was measured. Specific binding of ¹²⁵I-CD14 was the calculated difference of radioactive material bound to LPS-coated and uncoated wells. The results are the mean ± standard deviations of three wells from one representative experiment.