DKK1 and systemic lupus erythematosus: Recently, Tveita and Rekvig [7] reported increased canonical WNT pathway activity in the kidneys during the development of nephritis in a lupus mouse model (NZB × NZW F1 mice), paralleled by an increase in renal and serum levels of the WNT inhibitor Dkk-1, which suggested that WNT signaling might play an important role during the development of nephritis in the lupus mouse model.