IL1B and fibrosis: However, TGFβR1 expression was up-regulated in only Hypoxia+IL-1β-treated PTECs, providing evidence for a potential autocrine TGF-β1/TGFβR1 signalling loop restricted to hypoxic-inflammatory conditions and capable of stimulating epithelial-to-mesenchymal transition (EMT) and tubulointerstitial fibrosis.