Lupus nephritis (LN) — inflammation of the kidney — can damage the kidney’s ability to remove waste from the body. Currently, the best way to diagnose kidney inflammation is with a biopsy, an invasive procedure that can sometimes have serious side effects. Researchers have been working to develop specific tests that can be done on urine samples. The results of this study showed that levels of mRNA for FOXP3 could potentially become a test that can be done on simple urine samples to help figure out what is going on in the kidney and to help predict responses to current treatments for people with lupus.