Rab1b knockdown does not impact Y. pestis invasion of macrophages.
RAW264.7 macrophages were reverse transfected with Rab1b, scrambled (Scr), or Copβ1 siRNA. 48 h after transfection cells were infected with Y. pestis CO92 pCD1(-)pGEN-PEM7::DsRED (MOI 7.5). 20 or 80 min post-infection cells and bacteria were fixed with paraformaldehyde and extracellular bacteria were stained by indirect immunofluorescence with anti-Y. pestis antibody. (A) Representative image showing differential staining of intracellular (red) and extracellular (green or yellow) bacteria. Scale bar is 5μm. Asterisk denotes intracellular Y. pestis. (B and C) Percentage of intracellular bacteria calculated at 20 and 80 min post-infection, respectively. ** = p<0.01, ns = not significant.