Salmonella intracellular proliferation: where, when and how?

Salmonella species proliferate within membrane-bound vacuoles of eukaryotic cells. Recent work has shown that macrophages are the main cell type supporting bacterial growth in vivo. In contrast, tissue culture models have traditionally described epithelial cells as the most permissive cells for bacterial growth. Unfortunately, no mechanism used by Salmonella to initiate growth within a vacuole has been characterised. Recently, it has been shown that Salmonella is capable of attenuating intracellular proliferation. This finding suggests that both the host and the pathogen contribute to a fine adjustment of the intracellular growth rate.