FIGURE 4.

Anti-WTA-antibodies inhibit MBL binding to WTA. a, inhibitory effects of serum IgGs on MBL binding to WTA. Effect of total IgGs or BSA on MBL (10 ng) binding to WTA (5 μg) was determined by ELISA. Total IgGs were prepared from adult serum using a protein G column. Data were representative of at least three independent experiments. b, IgG-depletion recovers MBL binding to WTA in adult serum. Serum MBL binding to purified WTA was determined for IgG-depleted (line) or parental adult serum (dot-line) by ELISA. Data were plotted on MBL amounts in each serum. IgGs were depleted using a protein-G column. c, affinity purification of anti-WTA antibodies. Nitrocellulose membranes spotted by mock (PBS, lane 1), purified WTA (lane 2), or WTA-free PG (lane 3) were incubated with commercially available human IVIG for 2 h at 4 °C. Eluted proteins from the membranes were analyzed by 12% SDS-PAGE with CBB staining. BSA from the blocking reagent (band a), IgG heavy chain (b), and IgG light chain (c) were determined by N-terminal sequencing. d, anti-WTA antibodies inhibit MBL binding to WTA. The effects of affinity-purified IgGs (1 μg) prepared in Fig. 4c were examined by ELISA. MBL binding to WTA was determined in ELISA as described in the legend to Fig. 4a. Data were representative of at least three independent experiments.