To test whether persistent transcriptional activity of NF-κB would inverse the surface display of TNFR1 due to infection with the ST-11 isolates, Hec-1B cells were transiently transfected with the plasmid pCA-IKK2 that was modified by insertion of EGFP marker to visualize transfected cells. Here, TNFRSF1A is linked to infection.