FIG 2.

Complement component C3 mediates enhanced bacterial uptake and macrophage death induction. MDM were infected with SCHU S4 (MOI = 80) in the presence of the indicated sera. *, significant differences in bacterial burden or LDH release when comparing test sera to HS at the indicated times p.i. The results shown are representative of three independent experiments. (B) Deposition of C3 peptides on SCHU S4 (8 × 10⁷ bacteria per lane) was detected via Western blotting. Purified C3 and iC3b proteins served as markers. These results are representative of three independent experiments.