MBL2 and infection: In a separate experiment, infection of THP-1 cells was significantly inhibited by preincubating 5% serum (native MBL concentration, 3,621 ng/ml) with competitors: EDTA (98% reduction with 10 mM; Figure 5B), mannan (97% reduction with 10 μg/ml; Figure 5B) and 3F8 (25% reduction with 0.1 μg/ml; Figure 5C).