NFKBIZ and infection: It should be noted that, at later time points of infection, expression levels of nfkbiz and il6 caused by strains α14 and MC58 reached that of MC58siaD−, indicating that the possible maximum levels of gene activation are finally induced by all three intracellularly replicating strains and/or extracellular bacterial components present in the media after antibiotic treatment at 4 h.