Fig. 2

Periodontitis induced by Ligature placement or Ligature/P.g. LPS increased serum level of pro-inflammatory cytokines in ApoE−/− mice. a–d Levels (pg·mL−1) of TNF-α, IL-1β, IL-6, and CRP from the mice sera. They were measured on pre-coated ELISA plates. ND not detected. *P < 0.05 in one-way ANOVA. Results represent the means ± SD performed in triplicate