Detection of bacteria within thrombi. (A-B) Representative immunofluorescence photomicrographs of spleens (A) and livers (B) from WT mice infected with 5 × 105 STm SL3261 for 0, 1, 7 and 21 days. MK, megakaryocyte; RP, red pulp; T, thrombus; V, vein; WP, white pulp. Fibrin, blue; CD31, white; CD41, red; STm, green (indicated with white arrows). For panels A and B, the second row shows a higher-magnification image of the area identified by the white box. (C-D) Frequency of detecting 0, 1, 2, or ≥3 bacteria in thrombi in sections from spleens and livers, respectively, from mice infected with 5 × 105 STm SL3261 for 0, 1, 7, or 21 days. (E-F) Line graphs showing the kinetics of thrombosis (blue) and bacterial colonization (red) in spleens and livers respectively, from mice infected with 5 × 105 STm SL3261 for 0, 1, 2, 7 or 21 days. Data are expressed as mean ± standard error of the mean from 152 thrombi counted in spleens from day 1–infected mice, 40 from day 7–infected mice, and 18 from day 21–infected mice. In liver, 411 thrombi were counted for days 7 and 23 for day 21 postinfection. In each case, thrombi were counted from at least 4 mice per group and are combined from 3 independent experiments. CFU, colony-forming unit.