Fig. 5

Peptide5 blocks Cx43-hemichannels to inhibit priming and activation of the NLRP3 inflammasome in primary tubule epithelial cells. Primary hPTECs were treated with pro-fibrotic cytokine TGF-β1 (10 ng/ml) for 48 h in the presence/absence of Peptide5 (25 µM) (a). qRT-PCR analysis of IL-1β, NLRP3 and IL18 mRNA (b) determined a role for Cx43 hemichannel activity in regulation of priming (step 1). Western blot analysis (c-e), IL1β secretion (f) and caspase 1 activity (g) determined an upstream role for Cx43-hemichannel activity in NLRP3 inflammasome activation. These data corroborate our in vivo observations and further suggest that aberrant Cx43 hemichannel activity sits upstream of NRLP3 inflammasome activation. All groups are n = 3–4. An ANOVA and Tukeys post-test was used for all analysis. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001