Interestingly, the urine levels of the biomarker proteins correlated with the serum levels of the same proteins, particularly in active LN patients, weakly (ALCAM), modestly (Hemopexin, PF-4, TFPI, VCAM-1) or strongly (properdin), as plotted in Figure 2, even though the serum levels could not distinguish active LN from other SLE patients, with most of the biomarkers. Here, VCAM1 is linked to systemic lupus erythematosus.