Figure 6. Primary human Mφ pre-ligated with fibrinogen are protected from L. monocytogenes-induced apoptosis.
Primary human macrophages were plated onto control wells or fibrinogen (Fb) coated wells for 18 h. Culture media was changed, and cells were infected with live L. monocytogenes (wild-type strain 10403S) at MOI 10, 20 (A) or MOI 5 (B, C).
A, Flow cytometry was used to assess apoptosis, measured by annexin V binding to phosphatidylserine in the DAPI negative population. In vitro infections were performed in triplicate wells, and results are presented as mean frequency ± SD of triplicate wells. Cell death was measured by positive staining for both annexin V and DAPI. Data are representative of at least 3 independent experiments.
B, Viable bacteria from macrophages were quantified 4 h post infection. 4 independent experiments are shown, with each symbol representing a different donor. Statistical analysis was done using the 2-tailed, paired Student t test, and intracellular burden between control-infected and Fb-infected macrophages was not statistically different.
C, Induction of multiple infection induced mRNAs was measured by qPCR, and results are presented as mean ± SD of triplicate wells normalized relative to GAPDH mRNA. Data are representative of at least 3 independent experiments.
