Detecting Immune Responses to Type III Secretion Systems

: Measuring immune responses against type III secretion and related molecules has been made easier with the advent of reporter cell lines. For example, the THP-1-XBlue and HEK-Blue cells from InvivoGen provide easy detection of gene activation under NF-kB and AP-1 control. In addition, many of these cells have been engineered to express specific pattern recognition receptors (PRRs) helping to elucidate activation pathways. In addition, the THP-1 parent cell line from ATCC provides a useful tool for evaluating cytokine release upon stimulation. This chapter will outline using X-blue reporter cell lines, setting up experiments to measure cytokine secretion, and general guidelines for cytokine quantification.