Hani Susianti

Analysis of urinary TGF-β1, MCP-1, NGAL, and IL-17 as biomarkers for lupus nephritis

This study was aimed to determine the diagnostic performance of transforming growth factor beta 1 (uTGF-β1), monocyte chemoattractant protein-1 (uMCP-1), neutrophil gelatinase-associated lipocalin (uNGAL) and interleukin 17 (uIL-17) in LN. Seventy participants were studied, categorized into three groups: 38 severe LN (class III-IV LN patients); 12 mild LN (class I-II LN patients); and 20 control (healthy volunteers). Diagnosis of SLE was based on the 1997 ARA criteria. Class NL classified according to ISN/RPS 2004. uTGF-β1, uMCP-1, uNGAL, uIL-17 levels were determined by ELISA, using spot urine. The level of uMCP-1 and uNGAL was significantly greater in severe or mild LN compared with control group (P<0.05). The level of uTGF-β1 and uIL-17 was significantly higher in severe LN than that controls group (P<0.05). The AUC of uTGF-β1, uMCP-1, uNGAL, uIL-17 was 66.50%; 86.90%; 87.50%; 71.70%, with the cut-off value of 27.13pg/ml; 1.54pg/ml; 446.30pg/ml; 36.62pg/ml. Only uNGAL showed a significant correlation with the activity (P=0.016; r=0.389) and chronicity indices (P=0.018; r=0.381). This study showed that uTGF-β1, uMCP-1, uNGAL, uIL-17 levels were increased in LN. The AUC values for each biomarker are indicating a good diagnostic value. Urinary NGAL had the best sensitivity and specificity followed by uMCP-1, uIL-17 and uTGF-β1. For combinations of two biomarkers, the best sensitivity and specificity were displayed by the combination of uTGF-β1 & u-NGAL, followed by uMCP-1 & uNGAL.

Changes to signal peptide and the level of transforming growth factor- β1 due to T869C polymorphism of TGF β1 associated with lupus renal fibrosis

Lupus Nephritis (LN) is a serious manifestation of lupus that can lead to End Stage Renal Disease (ESRD). Fibrosis is the main feature of ESRD, and it is likely influenced by Transforming Growth Factor Beta1 (TGFβ1). The T869C gene polymorphism of TGFβ1 is assumed to change the signal peptide, that has potential to interfere the urine production and renal protein expression of TGFβ1. The influence of T869C gene polymorphism on TGFβ1 production and renal fibrosis was evaluated in this study. Subjects were 45 patients LN with renal fibrosis and 45 participants without renal fibrosis as control, that were recruited from 2011 to 2013.Their urinary TGFβ1 levels and TGFβ1 gene polymorphisms were examined. All lupus patients underwent renal biopsy to assess their protein expression of TGFβ1 in the renal tissue by immunohistochemistry and their renal fibrosis by morphometry and chronicity index. Changes in the signal peptide interaction with Signal Recognition Particle (SRP) and translocon of endoplasmic reticulum were analyzed by Bioinformatics. Levels of urinary and protein expression of TGFβ1 increased in the LN with renal fibrosis group. There were significant differences in levels of urinary TGFβ1 in T, C allele and TT, TC, CC genotypes between case and control groups. Furthermore, patients with C allele are 3.86 times more at risk of renal fibrosis than T allele. The C allele encodes proline, which stabilizes the interaction of the TGFβ1 signal peptide with SRP and translocon, resulting in elevation of TGFβ1 secretion. Our results indicated that T869C gene polymorphism of TGFβ1 changes the signal peptide, that contributes to the production of urinary TGFβ1 and affects renal fibrosis in lupus nephritis.

The Potential effect of G915C polymorphism in regulating TGF-β1 transport into Endoplasmic Reticulum for cytokine production.

The TGF-β1 cytokine concentration is known to be higher in nephritis with implied Lupus Nephritis severity. The production of TGF-β1 cytokine is associated with G915C polymorphism. Therefore, it is of interest to study G915C polymorphism. The G915C polymorphism changes codon 25 which encodes arginine into proline in the signal peptide of TGF-β1. The amino acid substitution affects signal peptide properties that may inhibit the transport of TGF-β1 into the endoplasmic reticulum and eventually decline the cytokine production. Hence, the effect of G915C polymorphism on the properties of the signal peptide, the ability of TGF-β1 transport into the endoplasmic reticulum and the concentrations of urinary TGF-β1 in Lupus Nephritis patients was studied. The arginine substitution into proline decreased the polarity of the signal peptide for TGF-β1. The increased hydrophobicity with increased binding energy of the signal peptide for TGF-β1 to Signal Recognition Particle (SRP) and translocon is shown. This implies decreased protein complex stability in potentially blocking the transport of TGF-β1 into the endoplasmic reticulum. This transport retention possibly hampers the synthesis and maturation of TGF-β1 leading to decreased cytokine production.

INTERLEUKIN-4 DAN INTERFERON GAMMA DI NEFRITIS LUPUS: HUBUNGAN AKTIVITAS PENYAKIT SERTA KEKAMBUHAN

Sampling for urinalysis to see the activity and the degree of recurrence of Lupus Nephritis (LN) is very difficult. New biomarkers that are more simple, sensitive, specific and non-invasive in assessing the activity of the LN need to be investigated. Interleukin-4 (IL-4) and interferon gamma (IFN-γ) were implicated to LN process. Urine samples from 17 LN patients were taken every month for 6 (six) months to examine the level of uIL-4, uIFN-γ, activity and recurrence of LN. Significant differences were observed in the uIFN-γ levels between the active and inactive LN groups (p=0.012), but not in uIL-4 levels (p=0.187). Correlations between each biomarker and renal domain score were weak (r=0.201, p=0.042 for uIL-4; r=0.268, p=0.006 for uIFN-γ). Significant differences were also found in the uIL-4 and uIFN-γ levels against LN recurrence (p=0.033; p=0.017). The best cut off values to assess recurrences and activity of LN were 8.17 pg/mL for uIL-4 showed a sensitivity of 74%, specificity 71%, NPV 90%, PPV 42% to assess recurrences and to assess activity of LN showed sensitivity 46%, specificity 75%, NPV 48%, PPV 78%. The cut off 18.58 pg/mL for uIFN-γ to predict recurrent and assess the activity of LN showed sensitivity 68%%, specificity 70%, NPV 88%, PPV 40% to predict the recurrent and to assess the activity of LN showed sensitivity 57%, specificity 64%, NPV 49%, PPV 73%. Based on the research, uIL-4 and uIFN-γ are not good enough to predict recurrence and activity of LN

PETANDA BIOLOGIK TERKINI LUPUS NEFRITIS

Lupus Nephritis (LN) is one of the serious clinical manifestation of Systemic Lupus Erythematosus (SLE). Early detection and treatment of renal activity may spare patients from renal damage. Conventional biomarkers such as urine sediment, proteinuria, creatinine, antids DNA antibody and their complement levels are not specific and sensitive enough in detecting the ongoing disease activity in the lupus kidneys and early relapse of nephritis. Renal biopsy is the gold standard in providing information on the histopathology of LN, but is invasive and it should take a serial of biopsies making it impractical when monitoring LN. Thus, some novel biomarkers are necessary to enhance the diagnostic accuracy and sensitivity of lupus renal disease, prognostic stratification, monitoring of treatment response and detection of early renal flares as well. Some novel biomarkers have been studied in LN, however, validation on a large scale of patients with different ethnic backgrounds is still needed.

The association between G-197A gene polymorphism of IL-17A with changes in protein interaction of IL-17A, levels of urinary IL-17, and degree of lupus nephritis abnormality

Elevated levels of IL-17 in systemic lupus erythematosus (SLE) patients have been reported to be correlated to renal disorders, but the involvement of the G-197A gene polymorphism of IL 17 in lupus nephritis (LN) and the degree of renal abnormality have not been reported. Therefore, the aim of this study was to investigate these associations. This study involved 30 LN patients and 20 healthy control. Levels of uIL-17 were measured by ELISA, while the G-197A gene polymorphisms of IL-17A were examined using polymerase chain reaction (PCR) and sequence analysis. Changes in the protein structure due to G-197A gene polymorphism of IL-17A were analyzed by in silico investigation. In addition, renal biopsies were performed to determine the degree of renal abnormality (classes I–VI). A significant difference was found between LN patients and the control group in term of uIL-17 levels (p = 0.004). However, the G-197A gene polymorphism of IL-17A between LN patients and the control group were not significantly different (p = 0.154). There were no difference in the levels of uIL-17 between patients and control group on G-197A gene polymorphism of IL-17A (p = 0.682). Also, there were no significant differences in G-197A gene polymorphism of IL-17A toward the degree of nephritis (p = 0.300). In silico investigation showed that G197A gene polymorphism of IL-17A resulted in changes of the pattern of IRF-4 binding to the promoter, thereby affecting its activity. In conclusion, the levels of uIL-17 in LN patients were significantly higher than those in the control group, but G-197A gene polymorphism of IL-17A did not cause varying levels of IL-17 and did not influence the degree of renal abnormalities in LN.

Urinary Neutrophil Gelatinase-Associated Lipocalin to Monitor Lupus Nephritis Disease Activity.

Background This study was conducted to determine whether there is an association between urinary neutrophil gelatinase-associated lipocalin (uNGAL) and urinary transforming growth factor-β1 (uTGF-β1) with lupus nephritis (LN) disease activity. Methods Urine samples from 18 LN patients were collected every month for six months then examined for uNGAL, uTGF-β1, and renal domain Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score. Results The uNGAL levels were significantly different between active and inactive LN (P < 0.05). uTGF-β1 levels were not different between active and inactive LN (P > 0.05). There was a significant correlation between uNGAL levels and renal domain SLEDAI score (r= 0.417, P < 0.05). There was no correlation between uTGF-β1 levels and renal domain SLEDAI score (r = 0.031, P > 0.05). Conclusion uNGAL is better than uTGF-β1 for differentiation of active and inactive LN. uNGAL can be considered as a biomarker to monitor LN disease activity.