Mtb Inactivates Rac1 in infected macrophages.

<p><b>A</b>. RAW macrophages were allowed to ingest Mtb wild type (WT) (MOI 20∶1) or coated latex beads (MOI 5∶1) then treated with LPS (200 ng/ml) for 15 min to activate Rho GTPases. Lysates were then prepared and examined for levels of active (GTP-bound) Rho GTPases by pull down with specific probes (Millipore kit) and western blot with Rac1, Rho, or Cdc42 antibodies (top panel). In the bottom panel, similar western blot analyses were applied to equal aliquots of untreated whole cell lysates to confirm that equal amounts of total Rho proteins were used in the pull down assay. <b>B</b>. RAW macrophages were infected with Mtb WT or Mtb Ndk-AS (MOI 20∶1) and cell lysates were assayed for Rac1 activation 0 min, 15 min, and 60 min post phagocytosis. Top panels indicate amount of active Rac1 detected in cell lysates and bottom panels indicates levels of Rac1 in untreated whole cell lysate aliquots. Data are representative of three independent experiments.