infection in the gallbladder triggers an intense inflammatory response, manifested by elevated levels (more than 10-fold) of proinflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP1) (Menendez et al., 2009). This evidence concerns the gene TNF and infection.