Figure 5. Apolipoprotein B (ApoB) contributes to resistance against S. aureus bloodstream infection in C57BL/6 mice.

(a) Relative fold change of Apob expression values in the kidneys of uninfected C57BL/6 respect to those in the kidneys of uninfected A/J mice determined by either RNA-Seq (white bars) or qRT–PCR (black bars). Each bar represents the mean relative fold change±s.d. of triplicates. (b) Expression of ApoB in kidneys of A/J (left) and C57BL/6 (right) mice determined by immunostaining of kidney tissue using specific antibodies against ApoB. Magnification X40. (c) Relative fold change of Apob expression values in the kidneys of S. aureus-infected C57BL/6 in comparison to those in the kidneys of S. aureus-infected A/J mice at 48 h of infection determined by either RNA-Seq (white bars) or qRT-PCR (black bars). Each bar represents the mean relative fold change±s.d. of triplicates. (d) Bacterial loads in the kidneys of A/J (blue symbols) and C57BL/6 (red symbols) mice treated with 4-Aminopyrazolo[3,4-d]pyrimidine (4-APP) (open symbols) or with vehicle alone (solid symbols) at 48 after intravenous inoculation with 2 × 10⁷ CFU of S. aureus strain SH1000. Each symbol represents the bacterial counts determined in an individual mouse and the horizontal lines represent the average±s.d. for each mouse strain (n=6, t-test, **P<0.01, ***P<0.001).