NFκB activation has been consistently reported in response to C. pneumoniae infection in vitro, over a wide range of infection times and in a wide variety of cell types, including epithelial cells (Gencay et al., 2003), monocytes (Donath et al., 2002), and especially endothelial cells, where infection is also often associated with IL-6 induction (Dechend et al., 1999; Kol et al., 1999; Visseren et al., 2002; Niessner et al., 2003). This evidence concerns the gene NFKB1 and infection.