Urinary galectin-3 binding protein (G3BP) as a biomarker for disease activity and renal pathology characteristics in lupus nephritis

Objective

There is an urgent need to identify novel biomarkers of LN to reflect renal histological changes. This study aims to investigate urinary G3BP levels in LN patients and their association with renal disease activity both clinically and pathologically.

Methods

This is a cross-sectional study. A total of 119 lupus nephritis patients were recruited. Thirty patients with chronic kidney diseases (CKD) and 27 healthy volunteers were also recruited as controls. Urinary G3BP was tested by ELISA. Renal histopathology was reviewed by an experienced renal pathologist. Other clinical variables were collected through chart review.

Results

The levels of uG3BP were significantly increased in active LN patients compared to those in inactive LN (p<0.001), CKD patients (p=0.01), and healthy controls (p<0.001). ROC analysis indicated a good discrimination ability of uG3BP to differentiate active LN from CKD patients (AUC=0.7), inactive LN (AUC=0.76), or healthy controls (AUC=0.87). uG3BP was positively correlated with SLEDAI (ρ=0.352, p<0.001), rSLEDAI (ρ=0.302, p<0.001), and SLICC RAS (ρ=0.465, p<0.001), indicating a role as a biomarker of disease activity. It also correlated with clinical parameters, including 24-h urine protein, ESR, and serum C3 levels. In patients with 24-h urine protein > 3.0 g/24h, uG3BP levels were higher in proliferative LN than in membranous LN (p=0.04). They could discriminate the two pathogenic types of LN (AUC=0.72), and they also positively correlated with AI (ρ=0.389, p=0.008) and scores of hyaline deposits (ρ=0.418, p=0.006). While in patients with 24-h urine protein ≤ 3.0 g/24h, uG3BP levels were not significantly different between proliferative and membranous LN, and there was no apparent relationship between uG3BP levels with AI or with scores of hyaline deposits, but they correlated positively with scores of cellular/fibrocellular crescents (ρ=0.328, p=0.04).

Conclusion

uG3BP is a non-invasive biomarker for clinically and histologically reflecting disease activity. It is associated with active histological changes and can be used as a surrogate biomarker when the renal biopsy is impractical.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02763-4.

TAFRO syndrome complicated by porto-sinusoidal vascular liver disease with portal hypertension: a case report

Porto-sinusoidal vascular liver disease (PSVD) is a disorder that can cause portal hypertension without liver cirrhosis. TAFRO syndrome is a systemic inflammatory disorder with a background of immunological abnormalities. We report a case of TAFRO syndrome complicated by PSVD with portal hypertension. A 39-year-old man developed refractory ascites and esophageal varices. Lymph node histology revealed multicentric Castleman disease-like features. Intravenous methylprednisolone and tocilizumab therapy improved ascites and renal dysfunction, but the patient developed severe infections. The diagnosis of TAFRO syndrome in patients complicated by PSVD with portal hypertension encourages the consideration of appropriate treatment for these patients.

Galectin-9 as a biomarker for disease activity in systemic lupus erythematosus

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by elevated interferon (IFN) signature genes. Galectin-9 (Gal-9) is a β-galactoside-binding lectin that is reportedly useful as a biomarker for IFN gene signatures. In a cross-sectional study of Japanese patients with recent-onset SLE, we aimed to determine whether raised serum Gal-9 levels were associated with the disease activity or organ damage seen in SLE patients.

Methods

The current study included 58 Japanese patients with SLE and 31 age-matched healthy individuals. Disease activity and organ damage were assessed using SLE Disease Activity 2000 (SLEDAI-2K) and Systemic Lupus International Collaborating Clinics (SLICC) damage index. Serum and cerebrospinal fluid (CSF) Gal-9 concentrations were quantified using ELISA. Correlation analyses between Gal-9 and clinical parameters including disease activity were performed.

Results

Serum levels of Gal-9 were significantly increased in patients with SLE compared with the control group (16.6 ng/ml, [interquartile range (IQR); 3.6–59.7] versus 4.74 ng/ml, [IQR; 3.0–9.5], p<0.0001). Gal-9 was significantly correlated with disease activity measures in the SLEDAI-2K. Serum Gal-9 levels were significantly greater in patients with SLE-related organ involvement (23.1 ng/ml, [IQR; 5.1–59.7] versus 12.5ng/ml, [IQR; 3.6–39.0], p = 0.013). Whereas there was no difference in serum levels of CXCL10 or M2BPGi between patients with and without SLE-related organ involvement. Serum levels of Gal-9 were significantly higher in SLE patients with active renal involvement determined by BILAG renal score (A-B) compared to those without active renal involvement (C-E). Whereas there was no significant difference in serum levels of Gal-9 between SLE patients with or without active other organ involvements (neurological or hematological) determined by BILAG score. SLE patients with detectable circulating IFN-α had raised serum Gal-9 levels. Levels of Gal-9 were significantly higher in the CSF from patients with recent-onset neuropsychiatric SLE (NPSLE) than in those from non-SLE controls (3.5 ng/ml, [IQR; 1.0–27.2] versus 1.2 ng/ml, [IQR; 0.9–2.1], p = 0.009).

Conclusions

Gal-9 could be a serologic marker of disease activity and organ involvement in SLE patients. Future studies evaluating the role of Gal-9 in the SLE phenotype may provide insights into SLE pathogenesis.

Serum Wisteria floribunda agglutinin-positive Mac-2-binding protein evaluates liver function and predicts prognosis in liver cirrhosis

OBJECTIVE

Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA⁺ -M2BP) is a novel glycobiomarker for evaluating liver fibrosis, but less is known about its role in liver cirrhosis (LC). This study aimed to investigate the utility of WFA⁺ -M2BP in evaluating liver function and predicting prognosis of cirrhotic patients.

METHODS

We retrospectively included 197 patients with LC between 2013 and 2016. Serum WFA⁺ -M2BP and various biochemical parameters were measured in all patients. With a median follow-up of 23 months, liver-related complications and deaths of 160 patients were recorded. The accuracy of WFA⁺ -M2BP in evaluating liver function, predicting decompensation and mortality were measured by the receiver operating characteristic (ROC) curve, logistic and Cox's regression analyses, respectively.

RESULTS

WFA⁺ -M2BP levels increased with elevated Child-Pugh classification, especially in patients with hepatitis B virus (HBV) infection. ROC analysis confirmed the high reliability of WFA⁺ -M2BP for the assessment of liver function using Child-Pugh classification. WFA⁺ -M2BP was also significantly positively correlated with the model for end-stage liver disease (MELD) score. Multivariate logistic regression analysis indicated WFA⁺ -M2BP as an independent predictor of clinical decompensation for compensated patients (odds ratio 11.958, 95% confidence interval [CI] 1.876-76.226, P = 0.009), and multivariate Cox's regression analysis verified WFA⁺ -M2BP as an independent risk factor for liver-related death in patients with HBV infection (hazards ratio 10.596, 95% CI 1.356-82.820, P = 0.024).

CONCLUSION

Serum WFA⁺ -M2BP is a reliable predictor of liver function and prognosis in LC and could be incorporated into clinical surveillance strategies for LC patients, especially those with HBV infection.