SPP1 and renal fibrosis: TGFBI is known to promote renal fibrosis and has previously been implicated in LN.19–21CEBPB encodes the CCAAT/enhancer binding protein-β and is necessary for macrophage-mediated removal of apoptotic debris.22 Osteopontin (SPP1) is produced by various immune cells and is important for regulating several aspects of the immune system including T-helper cell balance and B cell production of antibodies.23 Overexpression of osteopontin has been implicated in the development of murine LN24 and is associated with human systemic lupus erythematosus (SLE).25