Fig. 3.
Binding of soluble CD40 from the serum of haemodialysis (HD) patients to CD40L. (a) BHKCD40L incubated in pooled serum from 10 HD patients (—) showed no flow cytometric staining for CD40. BHKwt cells (·····) incubated in pooled serum from HD patients were used as negative control, BHKCD40L incubated with 5 μg/ml CD40Fc served as positive control (–––––). (b) Neither BHKCD40L (—) nor BHKwt (·····) stained for CD40Fc at 5 ng/ml, whereas BHKCD40L incubated in CD40Fc at 5 μg/ml were strongly positive for CD40 (–––––). BHKwt did not stain for CD40FC at 5 μg/ml (not shown).