Effect of TLR4 stimulation on the rapid antibody-mediated clearance of <i>B. parapertussis</i>.

<p>(A) Groups of wild type (C3H/HEOuJ) and TLR4-deficient (C3H/HEJ) mice were inoculated with <i>B. parapertussis</i> (Bpp) or Bpp and heat-killed <i>B. bronchiseptica</i> (HK Bb) and given I.P. injections of naïve serum (NS) or immune serum (IS). Groups of mice were also inoculated with Bpp and (B) Bb LPS (BbLPS) or (C) <i>E. coli</i> LPS (EcLPS) and treated with naïve or immune serum. Bacterial numbers were quantified 3 days later and are expressed as the Log₁₀ mean+/−SD. Asterisks denote P-values<0.05.