Figure 2.

AdsA is a virulence factor that enables staphylococcal replication and abscess formation in vivo. Staphylococcal burden in kidneys after intravenous challenge of BALB/c mice (n = 10) with (A) 10⁷ CFU of wild-type S. aureus Newman or its isogenic adsA mutant and (C) S. aureus USA300 wild-type or its isogenic adsA mutant was enumerated as log₁₀ CFU per gram of tissue 5 d after infection. Data are representative of two independent analyses. Microscopic images of hematoxylin-eosin–stained kidney tissue were obtained after necropsy of mice infected with (B) wild-type S. aureus Newman and adsA mutants or (D) wild-type S. aureus USA300 and corresponding adsA mutants. Black arrows denote the abscess lesions. Data are representative samples of cohorts of five animals per bacterial strain and two independent analyses. Bars: (top) 1 mm; (bottom) 100 µm. (E) Staphylococcal burden—wild-type (WT), adsA, or adsA:padsA S. aureus Newman—in blood of BALB/c mice (n = 10) was measured as log₁₀ CFU per 0.5 ml of blood retrieved by cardiac puncture at 30 and 90 min after intravenous challenge with 10⁷ CFU. Horizontal red bars represent mean CFUs in each cohort. Data are representative of three independent analyses using cohorts of 10 mice per bacterial strain per time point. Unpaired Student's t tests were used for statistical analysis.