Modulation of Stat-1 in Human Macrophages Infected with Different Species of Intracellular Pathogenic Bacteria

Figure 2

p-tyr₇₀₁Stat-1 expression in human macrophages in response to Gram-negative bacterial infections. Ten-day-old macrophages were infected with Salmonella typhimurium (a, b) or Legionella pneumophila (c, d). After removing extracellular microorganisms, cells were exposed for 30 min to gentamicin to kill noningested bacteria and then cultured for an additional 3 days in fresh medium containing gentamicin. At the indicated time, the intracellular viable bacteria were determined by enumeration of CFU in specific medium ((a) and (c)), and data are the mean of three independent experiments ± SEM. Stat-1 and p-tyr₇₀₁Stat-1 expression levels were evaluated by Western blot assay at the same times ((b) and (d)). Data were normalized on untreated (control) cells as a percentage increase. expression levels are significant compared to control cells; -1 expression levels are significant compared to control cells.

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