IL6 and Salmonella Infections: Furthermore, IAA treatment significantly inhibited Salmonella infection-induced pro-inflammatory responses, as evidenced by inhibiting mRNA (Il1b, Il6, Il18, Tnfa, Nos2) expression and nitric oxide secretion of Salmonella-infected RAW 264.7 macrophage cells, which was blocked by the presence of AHR inhibitor CH-223191 (Figure 5—figure supplement 2B-G).