Fibrosis without fibroblast TGF-β receptors?

A report by Neelisetty et al. suggests that TGFBR2 deletion from matrix-producing interstitial cells results in decreased transforming growth factor-β (TGF-β) signaling in the cells but does not decrease renal fibrosis after injury. Considered in the context of TGF-β signaling in different cell types involved in renal fibrosis and the existence of other ligands that may produce fibrosis, these findings are provocative, but owing to technical issues of recombination efficiency in inducible models of Cre-lox gene deletion, further studies are needed.