FIG. 3.

Binding of complement regulators factor H and FHL-1 by different B. spielmanii isolates. B. spielmanii isolates A14S, PC-Eq17, PMai, PHap, and PMew incubated in NHS-EDTA were extensively washed with 0.15 M NaCl, 0.03 M phosphate, 0.02% sodium azide, pH 7.2, containing 0.05% Tween 20, and bound proteins were eluted using 0.1 M glycine (pH 2.0). Both the last wash (w) and the eluate (e) fractions obtained from each strain were separated under nonreducing conditions in a 12.5% SDS-PAGE gel, transferred to nitrocellulose, and probed with either MAb VIG8 specific for SCR20 of factor H or MAb B22 for SCR5 of factor H and FHL-1.