PSMB2 and escherichia coli infection: However, when NHEKs were treated with PSMβ2 in the absence of an inflammatory stimulus, we identified the downregulation of genes within GO terms such as “cytokine-mediated signaling” and “pathogenic E. coli infection” (Figure 3—figure supplement 2), suggesting that exposure to PSMβ2 primes cells to dampen potential inflammatory mediators in response to TLR ligands.