C3 and infection: In our pneumococcal meningitis mouse model Cfh−/− mice had significantly lower C3 levels in plasma and brain at 5 (26.35 vs. 466 μg/ml plasma, P < 0.001 and 0.22 vs. 2.33 μg/mg brain tissue, P < 0.001) and 20 h (280.30 vs. 898.30 μg/ml plasma, P < 0.001 and 3.70 vs. 11.29 μg/mg brain tissue, P = 0.006) after infection (Fig. 4b).