CR3 inhibits while TLR2 activates pro-inflammatory responses in human macrophages after Schu S4 infection.

<p>hMDMs were transfected with scrambled siRNA or siRNA targeting CD11b or TLR2. 48 hrs after transfection cells were infected with Schu S4 (<i>Ft</i>) or <i>F. novicida</i> (<i>Fn</i>) in the presence or absence of serum at an MOI of 50∶1. TNFα (A) and IL-1β (B) levels at 16 h post infection in the culture supernatants were measured by ELISAs. Data are representative of 3 independent experiments performed in triplicates. The data were analyzed by 1-Way ANOVA and Tukey's Multiple Comparison Test. * p<0.05, **p<0.005, n.s., not significant. (C) After siRNA transfection hMDMs were infected with non-opsonized or serum pre-opsonized <i>Ft</i> Schu S4 at an MOI of 250∶1. Infections were synchronized as described in the <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003114#s4" target="_blank">materials and methods</a>. Cell lysates were collected at 5, 15 and 30 min post infection and subjected to Western blot analysis using antibodies against phospho-ERK1/2, phospho-p38 and β-actin. Uninfected resting cells (R) were also included as control. <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003114#s2" target="_blank">Results</a> are representative of at least 3 independent experiments.