Fibroblast Activating Protein Inhibitor PET Imaging in Lupus Nephritis

Abnormal high expression of fibroblast activating protein (FAP) has been found in inflammatory reactions and benign fibrosis tissue. Autoimmune nephropathy such as lupus nephritis (LN) can lead to tubular atrophy and excessive deposition of extracellular matrix, which may be accompanied by abnormally increased expression of activated FAP in kidney tissue, and lead to renal fibrosis and long-term renal failure. This makes 68Ga-labeled FAP inhibitor (FAPI) positron emission tomography (PET) imaging the potential to early assess disease severity, predict disease progress and aid treatment planning in patients with LN. Compared to renal pathological puncture, 68Ga-FAPI PET is a new tool for non-invasive, repeatable assessment of renal fibrotic activation.