SPI1 and Salmonella Infections: Since AvrA translocated through TTSS inhibits Salmonella infection-induced JNK pathway, but not the NF-κB pathway, we further investigated whether AvrA modulated the qualitative and/or quantitative output of the SPI-1-induced transcriptional reprogramming stimulated by S. Typhimurium in cultured intestinal epithelial cells.