MAPK1 and infection: Infection of HT29 cells with wild-type S. typhimurium resulted in activation of MAPKs ERK1&2, the SAPKs p38, JNK and IKK (Fig. 5) as determined by use of activation-indicating phospho-specific antibodies in immunoblot (IB) analysis or antibody-specific immuno-kinase assays (KA) for JNK and IKK using their respective substrates GST-cJun 1–79 and GST-IκBα1–54 [37-39].