Urine Soluble CD163 Is a Promising Biomarker for the Diagnosis and Evaluation of Lupus Nephritis

Abstract

IntroductionUrine-soluble CD163 (usCD163) is released from alternatively activated macrophages involved in the resolution of inflammation in glomeruli and plays an important role in glomerulonephritis. This study explored the role of usCD163 in patients with systemic lupus erythematosus (SLE).Materials and MethodsusCD163 concentrations were measured cross-sectionally in 261 SLE patients in Taiwan. Clinical and laboratory data were collected, and SLE disease activity scores were calculated to assess the correlation with usCD163.ResultsSLE patients with high usCD163 levels tended to be younger, with a higher hospital admission rate, higher prednisolone dose, lower estimated glomerular filtration rate, higher urine protein creatinine ratio (UPCR), more pyuria and hematuria, higher levels of inflammatory markers, higher rates of anemia, neutropenia, and lymphopenia, lower complement 3 (C3) levels, higher anti-double-stranded DNA antibody (anti-dsDNA Ab) levels, and higher disease activity scores (p < 0.05). usCD163 levels were significantly higher in patients with active lupus nephritis (LN) than in those with extrarenal or inactive SLE and correlated with UPCR, disease activity, and anti-dsDNA Ab levels. SLE patients with high usCD163 levels tended to have a higher chronic kidney disease stage.Discussion and conclusionThe usCD163 level correlates with the severity of LN and disease activity in renal SLE.

Urinary soluble CD163 is useful as “liquid biopsy” marker in lupus nephritis at both diagnosis and follow-up to predict impending flares

“…Another advantage to introducing urinary sCD163/creatinuria ratio determination as an LN biomarker is to overcome 24-h proteinuria and PCR limitations regarding tubular proteinuria (<25 kDa proteins) and the attribution of proteinuria to LN in a context of permanent renal damage, diabetes, hypertensive nephropathy, urinary tract infection, and other situations. Consequently, the urinary sCD163/creatinuria ratio used as a biomarker better predicts disease activity than PCR in our study, which is in agreement with previous studies [ 17 , 28 , 31 ]. We propose to fix the threshold for LN-A at 320 ng/mmol based on a specificity of 100 %, allowing the urinary sCD163/creatinuria ratio to discriminate LN-A in an SLE background.…”

Urinary Biomarkers for Lupus Nephritis: A Systems Biology Approach

“…Beyond IL-16, CD163-a macrophage-specific hemoglobin scavenger receptor upregulated during inflammation-has been consistently identified as a urinary biomarker through ELISA and single-cell transcriptomics techniques in patients with LN [51][52][53]. Urinary CD163, closely following IL-16, significantly correlates with LN severity indicated by the NIH activity index and histological activity [48,54].…”

“…Correlates with LN severity and treatment response, predicts one-year response more accurately than traditional measures. [48,[51][52][53][54] Proteomic Panel (ICAM2, FABP4, FASLG, IGFBP-2, SELE, TNFSF13B/BAFF) Distinguishes active renal disease from inactive disease in patients with LN with high accuracy (AUC > 0.8), correlates with clinical disease activity.…”