MAP2K4 and infection: The genes IKBKB, IRAK3, IRF5, MAP2K4 (MEK4), MAPK14 (p38), MAPK8 (JNK1) and NFKB1 (p50) were upregulated not only in both cell types, but also after infection with whole bacteria of P. gingivalis W83 as well as with the membrane fraction.