The dysregulation of bacterial virulence factors in the absence of katG may impact the host inflammatory response.49 The evaluation of the transcriptional levels of pro-inflammatory cytokines revealed that the mRNA expression of IL-2, IL-6 and TNF-α increased by ≥50 folds in RAW264.7 and Caco-2 cells receiving ∆katG mutant 12 h post-infection. This evidence concerns the gene IL6 and infection.