Figure 4.

EVs subpopulations bearing exosome and Mtb molecules can be separated by sucrose density gradient centrifugation. Macrophages were infected for 4 h with Mtb (MOI = 5), washed and incubated for 20 h. EVs were purified by differential ultracentrifugation from the conditioned medium, overlaid on a continuous 0.2-1.8 M sucrose gradient, and centrifuged for 19 h at 110,000 × g. Gradient fractions were collected and analyzed by Western blotting with Abs specific for exosome or Mtb molecules. Results are representative of three independent experiments.