Figure 3.

Binding of complement components to borrelial proteins. Binding of recombinant proteins to complement C3 (A), C3b (B), C4 (C), C4b (D), and C5 (E) was assessed by ELISA. Microtiter plates were coated with 500 ng His₆-tagged proteins and incubated with the respective complement proteins (5 µg/ml each). Protein-protein complexes were detected using specific antibodies. Dose-dependent binding of C3, C3b, C4b, and C5 to CbiA (F). Microtiter plates were coated with 100 ng His₆-tagged CbiA or 100 ng BSA and incubated with increasing concentrations with complement proteins and binding was analyzed with specific antibodies. Absorbance of each test was measured at 490 nm. Data represent means and SEM from three separate experiments, each performed at least in triplicate. Raw data were analyzed by one-way ANOVA with post hoc Bonferroni correction. ***P < 0.001, **P < 0.01, *P < 0.05.