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Aim: We explored the concentrations of urinary neutrophil gelatinase-associated lipocalin (NGAL) in healthy adults in the Jiangsu region in Eastern China and established a reference interval using latex-enhanced immunoturbidimetry to provide important guidelines for the interpretation and application of urinary NGAL in clinical practice. Methods: In total, 1970 eligible subjects from four regions were included in this study. The urinary NGAL levels were measured using an AU5800 automatic biochemical analyzer with its matched reagents. The urinary NGAL reference interval was established using the one-sided percentile method (95th percentile). Results: The urinary NGAL data were non-normally distributed. The urinary NGAL levels were not significantly different by sex or age. Therefore, the urinary NGAL reference interval in healthy adults in the Jiangsu region in Eastern China was

Purpose: To investigate the clinical value of urine interleukin-18 (IL-8), neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) for the early diagnosis of acute kidney injury (AKI) in patients with ureteroscopic lithotripsy (URL) related urosepsis. Methods: A retrospective study was carried out in 157 patients with urosepsis after URL. The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8, NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0, 4, 12, 24 and 48 h after the surgery. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI. Results: The level of urine IL-8, NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4, 12, 24 and 48 h (p

Lipocalins are important carriers of preferentially hydrophobic molecules, but they can also bind other ligands, like highly polar siderophores or intact proteins. Consequently, they are involved in a variety of physiological processes in many species. Since lipocalins are mainly extracellular proteins, they have to interact with cell receptors to exert their biological effects. In contrast to the large number of lipocalins identified in the last years, the number of receptors known is still limited. Nevertheless, some novel findings concerning the molecules involved in cellular uptake or signaling effects of lipocalins have been made recently. This review presents a detailed overview of the receptors identified so far. The methods used for isolation or identification are described and structural as well as functional information on these proteins is presented essentially in chronological order of their initial discovery.

OBJECTIVES To review urinary protein biomarkers as potential non-invasive, easily obtainable, early diagnostic tools in renal cell carcinoma (RCC). METHODS A PubMed database search was performed up to the year 2020 to identify primary studies reporting potential urinary protein biomarkers for RCC. Separate searches were conducted to identify studies describing appropriate methods of developing cancer screening programmes and detection of cancer biomarkers. RESULTS Several urinary protein biomarkers are under validation for RCC diagnostics, e.g. aquaporin-1, perilipin-2, carbonic anhydrase-9, Raf-kinase inhibitory protein, nuclear matrix protein-22, 14-3-3 Protein β/α and neutrophil gelatinase-associated lipocalin. However, none has yet been validated or approved for clinical use due to low sensitivity or specificity, inconsistencies in appropriate study design, or lack of external validation. CONCLUSIONS Evaluation of biomarkers' feasibility, sample preparation and storage, biomarker validation, and the application of novel technologies may provide a solution that maximises the potential for a truly non-invasive biomarker in early RCC diagnostics.

Neutrophil gelatinase-associated lipocalin (NGAL) is an acute phase protein that has been reported as a potential marker for pre-dementia stages of Alzheimer's disease (AD). Longitudinal studies for its association with the conversion of mild cognitive impairment to AD is still lacking. This study included n = 268 study participants with subjective cognitive decline (SCD) (n = 82), mild cognitive impairment (MCI) (n = 98) and AD dementia (n = 88) at baseline and two-year follow-up clinical assessments. Serum and cerebrospinal fluid (CSF)NGAL, CSF amyloid beta(1-42), total-Tau, and phospho-Tau levels were measured with ELISA analysis. CSF NGAL levels were significantly lower in MCI participants compared to people with SCD at baseline. Lower baseline CSF NGAL levels predicted MCI converters to AD dementia vs. non-converters after 2-years follow-up. A positive correlation between CSF NGAL and amyloid beta(1-42) was found particularly in MCI participants at baseline. NGAL in CSF holds potential to be used as a predictive marker for the conversion of MCI to AD dementia and may reflect pathophysiological processes of prodromal AD neuropathology. (C) 2021 The Authors. Published by Elsevier Inc.

Increased neutrophil gelatinase-associated lipocalin (NGAL) levels are associated with toxic or ischemic renal injury.This study aimed to assess the usefulness of serial NGAL measurements with a point-of-care assay in patients with left ventricular systolic dysfunction (LVSD) for earlier detection of contrast-induced nephropathy (CIN).A total of 84 patients with LVSD patients referred for coronary angiography were consecutively enrolled in the study. The study population was divided into two groups as the CIN and the non-CIN groups according to the CIN's determination. The serum creatinine levels were calculated 24 h before the procedure and at the 48th and 72nd h after the cardiac catheterization. The plasma NGAL concentration was measured before and at 4 and 24 h after the cardiac catheterization.Baseline and serial NGAL levels were significantly higher in patients with CIN compared to the patients without CIN. NGAL 24th h levels after the index procedure were found to be an independent and significant predictor of CIN in multivariate analysis.Serial point-of-care NGAL measurements might help earlier detection of CIN in patients with heart failure after coronary angiography.

Chronic (neuro)inflammation plays an important role in many age-related central nervous system (CNS) diseases, including Alzheimer's disease, Parkinson's disease and vascular dementia. Inflammation also characterizes many conditions that form a risk factor for these CNS disorders, such as physical inactivity, obesity and cardiovascular disease. Lipocalin 2 (Lcn2) is an inflammatory protein shown to be involved in different age-related CNS diseases, as well as risk factor conditions thereof. Lcn2 expression is increased in the periphery and the brain in different age-related CNS diseases and also their risk factor conditions. Experimental studies indicate that Lcn2 contributes to various neuropathophysiological processes of age-related CNS diseases, including exacerbated neuroinflammation, cell death and iron dysregulation, which may negatively impact cognitive function. We hypothesize that increased Lcn2 levels as a result of age-related risk factor conditions may sensitize the brain and increase the risk to develop age-related CNS diseases. In this review we first provide a comprehensive overview of the known functions of Lcn2, and its effects in the CNS. Subsequently, this review explores Lcn2 as a potential (neuro)inflammatory link between different risk factor conditions and the development of age-related CNS disorders. Altogether, evidence convincingly indicates Lcn2 as a key constituent in ageing and age-related brain diseases.

Background Current methods of processing and storing urine samples have not been compared systematically to determine optimal conditions for advancing research on urinary biomarkers. Often, preanalytical handling is nonideal, especially considering the COVID-19 pandemic; consequently, we compared the effects of different short-term storage and processing methods on urinary biomarker measurements. Methods Spot urine samples were collected via a Foley catheter from 20 hospitalized patients from the Yale New Haven Hospital within 48 hours postcardiac surgery. The effects of 3 urine storage and processing methods on biomarkers were tested: (a) 48-hour temporary storage at 4 °C prior to freezing at −80 °C, (b) 48-hour temporary storage at 25 °C prior to freezing at −80 °C, and (c) no centrifugation and immediate storage at −80 °C. Established Meso-Scale Device assay methods were used to measure the urine concentrations of 18 biomarkers: interferon gamma (IFN-ɣ), interleukin (IL)-10, IL-12p70, IL-13, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-18, tumor necrosis factor alpha (TNF-α), epidermal growth factor (EGF), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin (OPN), uromodulin (UMOD), kidney injury molecule-1 (KIM-1), monocyte chemoattractant protein-1 (MCP-1), and chitinase-3-like protein 1 (YKL-40). Results Measurements of most biomarkers investigated remained stable after temporary storage at 4 °C. IL-6, IL-8, KIM-1, MCP-1, YKL-40, EGF, and NGAL were stable across all 3 processing conditions. IL-12p70 and IL-4 demonstrated significant differences in all tested conditions compared to the reference standard. Conclusions We identified several notable biomarkers that are robust to variations in preanalytical techniques and can be reliably investigated with nonideal handling conditions.

Inflammatory breast cancer (IBC) is an aggressive form of primary breast cancer characterized by rapid onset and high risk of metastasis and poor clinical outcomes. The biological basis for the aggressiveness of IBC is still not well understood and no IBC‐specific targeted therapies exist. In this study, we report that lipocalin 2 (LCN2), a small secreted glycoprotein belonging to the lipocalin superfamily, is expressed at significantly higher levels in IBC vs non‐IBC tumors, independently of molecular subtype. LCN2 levels were also significantly higher in IBC cell lines and in their culture media than in non‐IBC cell lines. High expression was associated with poor‐prognosis features and shorter overall survival in IBC patients. Depletion of LCN2 in IBC cell lines reduced colony formation, migration, and cancer stem cell populations in vitro and inhibited tumor growth, skin invasion, and brain metastasis in mouse models of IBC. Analysis of our proteomics data showed reduced expression of proteins involved in cell cycle and DNA repair in LCN2‐silenced IBC cells. Our findings support that LCN2 promotes IBC tumor aggressiveness and offer a new potential therapeutic target for IBC., In this study, the authors demonstrate that lipocalin 2 (LCN2) is highly upregulated in inflammatory breast cancer (IBC), a rare, rapidly‐progressing and aggressive variant of primary breast cancer. Depletion of LCN2 in IBC cell lines reduced colony formation, migration, and cancer stem cell populations in vitro and inhibited tumor growth, skin invasion, and brain metastasis in mouse models of IBC.

Introduction and objectives: With increasing pet allergies among pediatric patients, the need for precise environmental care is increasing. We investigated the clinical, immunological, and environmental characteristics of pediatric patients sensitized to a dog to evaluate the cross-antigenicity of canine lipocalin Can f 1 with feline lipocalin Fel d 1 and Syrian hamsterextract.Materials and methods: The protein fractions of the processed and commercial Syrian hamster extracts were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). An enzyme-linked immunosorbent assay (ELISA) inhibition test was performed on Can f 1, Fel d 1, and processed Syrian hamster extract, and the antigen-specific immunoglobulin E (IgE)-binding capacity for each antigen was analyzed using serum samples from patients.Results: Twelve of 19 patients with a median age of 40.5 months were symptomatic when exposed to dogs. Eleven (91.7%) patients showed a positive IgE response to Can f 1. Two patients were positive for Fel d 1-specific IgE antibody, and one was positive for hamster-specific IgE antibody. SDS-PAGE confirmed the presence of different patterns of protein bandsbetween the commercial and processed hamster extracts. There was no cross-antigenicity among Can f 1, Fel d 1, and processed Syrian hamster extract.Conclusions: Since the standard commercial hamster extract did not contain Syrian hamster antigens that were diverse enough, caution should be taken when using it. In children allergic to cats and dogs, sensitization to isolated Can f 1 or Fel d 1 is unlikely to cause cross-reactivity to Syrian hamster hair and epithelium.

BACKGROUND To explore the value of serum soluble fms-like tyrosine kinase 1 (sFlt-1), CXC chemokine ligand 16 (CXCL16), and lipocalin 2 (LCN-2) in the diagnosis and grading of preeclampsia (PE). METHODS A total of 186 patients with PE diagnosed and treated in our hospital were included. According to the disease severity, the patients were divided into the mild PE group (99 cases) and the severe PE group (87 cases). A total of 72 healthy pregnant women who underwent antenatal care were selected as the healthy control group. The levels of serum sFlt-1, CXCL16, and LCN-2 before medication were compared among the patients, and the diagnosis and grading value of the above 3 indicators were analyzed. RESULTS For PE patients vs. healthy controls, the levels of sFlt-1 (132.71±14.49 vs. 68.43±9.28 µg/L), CXCL16 (2.15±0.35 vs. 0.61±0.12 µg/L), and LCN-2 (70.81±8.25 vs. 19.22±3.14 µg/L) were all significantly higher in PE patients than in the healthy controls (P

The exact role of adipokines in the pathogenesis of gestational diabetes mellitus (GDM) still remains not fully clear, and multiple studies have analyzed their potential contribution to the pathophysiology of this pregnancy complication. This study is aimed at evaluating serum chemerin, lipocalin 2, and apelin concentrations in GDM and healthy pregnant patients, assessing the correlation between these adipokines, and suggesting the potential role of these cytokines in the diagnosis and pathophysiology of GDM. The study comprised 237 pregnant women: 153 with GDM and 84 with physiological pregnancy. Serum concentrations of chemerin, lipocalin 2, and apelin were obtained at 24–29 weeks of gestation. The mean concentrations of chemerin and lipocalin 2 were significantly higher in the GDM group. The concentration of apelin was slightly higher in the GDM group, but not statistically significant. The strong positive correlation between chemerin and lipocalin 2 concentrations was noticed in both groups. Our data suggest that maternal chemerin and lipocalin 2 may play a significant role in the pathophysiology of GDM. We imply that these adipokines could potentially be established as novel biomarkers for the early identification of GDM. However, more studies are needed to analyze the effect of these adipokines on glucose metabolism during early pregnancy.

Background The inflammatory process in juvenile idiopathic arthritis (JIA) involves both the innate and the adaptive immune system. The turnover and activity of neutrophil granulocytes may be reflected by proteins secreted from primary or secondary granules and from the cytoplasm of sequestered cells. Our primary aim was to compare the levels of the secondary neutrophil granule protein human neutrophil lipocalin (HNL), in JIA patients and controls, and to explore a possible priming of neutrophils through parallel analyses in plasma and serum. A secondary aim was to relate the levels of HNL to two other well-studied leukocyte proteins, S100A8/A9 and myeloperoxidase (MPO), as well as to clinical aspects of JIA. Methods The concentrations of the three biomarkers in serum, two of them also in plasma, were measured using enzyme-linked immunosorbent assay in 37 children with JIA without medical treatment, in high disease activity based on juvenile arthritis disease activity score 27 (JADAS27), 32 children on medical treatment, mainly in lower disease activity, and 16 healthy children. We assessed for differences between two groups using the Mann-Whitney U test, and used the Kruskal-Wallis test for multiple group comparisons. Spearman rank correlation, linear and multiple regression analyses were used for evaluation of associations between biomarker concentrations and clinical scores. Results The concentrations of HNL and MPO in serum were significantly increased in children with JIA (p p = 0.002) compared with healthy children, but we found no difference in the plasma levels of HNL and MPO between children with JIA and controls. The serum concentrations of MPO and HNL were unaffected by medical treatment, but S100A8/A9 was reduced by medical treatment and correlated with JADAS27 in both univariate (r = 0.58, p Conclusions Neutrophil granulocytes in children with JIA are primed to release primary and secondary granule proteins, without relation to medical treatment, whereas signs of increased turnover and sequestration of neutrophil granulocytes are reduced by treatment. Levels of neutrophil-originating proteins in serum most likely reflect underlying disease activities of JIA.

Acute kidney injury (AKI) is increasingly being seen in patients with acute coronary syndromes (ACS) and it is associated with higher short-term and long-term morbidity and mortality. Therefore, it is of paramount importance to identify those ACS patients at risk for the development of AKI. The objective of this study was to evaluate two different plasma biomarkers calprotectin and neutrophil gelatinase-associated lipocalin (NGAL) in early detecting the development of AKI in ACS patients.172 ACS patients admitted to the Coronary Care Unit in Yantai Yuhuangding Hospital were prospectively enrolled. Their blood samples were obtained on admission and subjected to enzyme-linked immunosorbent assay to determine the levels of novel biomarkers. The clinical data and biomarkers were recorded and analyzed.In this study, 23 (13.4%) patients had a diagnosis of AKI. Statistical analysis demonstrated that in ACS patients with AKI, the following two biomarkers were significantly higher than these without AKI: plasma calprotectin (5942.26 ± 1955.88 ng/mL vs. 3210.29 ± 1833.60 ng/mL, p 0.001) and plasma NGAL (164.91 ± 43.63 ng/mL vs. 122.48 ± 27.33 ng/mL, p 0.001). Plasma calprotectin and NGAL could discriminate the development of AKI respectively with an area under the ROC curve (AUC) of 0.864 and 0.850. A combination of the two plasma biomarkers calprotectin and NGAL could early discriminate AKI in ACS patients with an AUC of 0.898.This study demonstrated a promising panel of plasma calprotectin and NGAL as early diagnostic biomarkers for AKI in ACS patients.

OBJECTIVES People living with HIV (PLWH) have a high risk of kidney injury. Measurement of serum creatinine, along with proteinuria, is not sensitive to detect early kidney injury. Here, we investigated novel urinary biomarkers of early renal injury in PLWH. METHODS We performed a cross-sectional study of 166 antiretroviral-naive PLWH and 99 HIV-negative persons who all had an estimated glomerular filtration rate > 90 mL/min/1.73 m2 . We compared the levels of seven urinary biomarkers between the two groups using the propensity score matching (PSM) approach and explored the risk factors associated with elevated urinary biomarkers in PLWH. RESULTS Eighty-three pairs were successfully matched based on PSM. Compared with the HIV-negative group, the HIV-positive group had higher ratios of N-acetyl-β-D-glucosaminidase (NAG) to urine creatinine (UCr), alpha1-microglobulin (α1-M) to UCr, kidney injury marker-1 (KIM-1) to UCr, neutrophil gelatinase-associated lipocalin to UCr, and epidermal growth factor to UCr, whereas the Tamm-Horsfall protein to UCr ratio and the abnormal albumin to UCr ratio were not significantly different. Positive correlations were observed between HIV RNA level and NAG: UCr (rs = 0.32; P

Acute kidney injury (AKI) is characterized by a sudden decrease in kidney function. Children with congenital heart disease are a special group at risk of developing AKI. We performed a systematic review of the literature to search for studies reporting the usefulness of novel urine, serum, and plasma biomarkers in the diagnosis and progression of AKI and their association with clinical outcomes in children undergoing pediatric cardiac surgery. In thirty studies, we analyzed the capacity to predict AKI and poor outcomes of five biomarkers: Cystatin C, Neutrophil gelatinase-associated lipocalin, Interleukin-18, Kidney injury molecule-1, and Liver fatty acid-binding protein. In conclusion, we suggest the need for further meta-analyses with the availability of additional studies.

Background: Multiple different pathophysiologic processes can contribute to worsening renal function (WRF) in acute heart failure.Methods and Results: We retrospectively analyzed 787 patients with acute heart failure for the relationship between changes in serum creatinine and biomarkers including brain natriuretic peptide, high sensitivity cardiac troponin I, galectin 3, serum neutrophil gelatinase-associated lipocalin, and urine neutrophil gelatinase-associated lipocalin. WRF was defined as an increase of greater than or equal to 0.3 mg/dL or 50% in creatinine within first 5 days of hospitalization. WRF was observed in 25% of patients. Changes in biomarkers and creatinine were poorly correlated (r < 0.21) and no biomarker predicted WRF better than creatinine. In the multivariable Cox analysis, brain natriuretic peptide and high sensitivity cardiac troponin I, but not WRF, were significantly associated with the 1-year composite of death or heart failure hospitali-zation. WRF with an increasing urine neutrophil gelatinase-associated lipocalin predicted an increased risk of heart failure hospitalization.Conclusions: Biomarkers were not able to predict WRF better than creatinine. The 1-year outcomes were associated with biomarkers of cardiac stress and injury but not with WRF, whereas a kidney injury bio-marker may prognosticate WRF for heart failure hospitalization.

Background/Aims: We investigated whether serum neutrophil gelatinase-associ ated lipocalin (NGAL) can predict mortality in patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). Methods: This study enrolled 169 patients who underwent serum NGAL testing at CRRT initiation from June 2017 to January 2019. The predictive power of se rum NGAL level for 28-day mortality was compared to the Acute Physiology and Chronic Health Evaluation-II (APACHE-II) score and Sequential Organ Failure Assessment (SOFA) score via area under the receiver operating characteristic curve (AuROC) value. Results: There were 55 survivors and 114 non-survivors at 28 days post-CRRT ini tiation. Median serum NGAL level was significantly higher in the non-survivor group than in the survivor group (743.0 ng/mL vs. 504.0 ng/mL, p = 0.003). The AuROC value of serum NGAL level was 0.640, which was lower than APACHE-II score and SOFA score values (0.767 and 0.715, respectively). However, in the low APACHE-II score group (< 27.5), AuROC value of serum NGAL was significantly increased (0.698), and it was an independent risk factor for 28 day-mortality (haz ard ratio, 2.405; 95% confidence interval, 1.209 to 4.783; p = 0.012). Conclusions: In patients with AKI requiring CRRT, serum NGAL levels may be useful for predicting short-term mortality in those with low APACHE-II scores.

Introduction: Acute kidney injury (AKI) is a frequent complication among patients in the intensive care unit (ICU). The limitations of serum Cr (sCr) in timely detecting AKI are well known. Beta-trace protein (BTP) is emerging as a novel endogenous glomerular filtration rate marker. The aim of this study was to explore the role of BTP as a marker of AKI. Methods: Patients admitted to the ICU undergoing surgery were included. BTP, sCr, Cystatin C (CysC), and neutrophil gelatinase-associated lipocalin (NGAL) were measured preoperatively, postoperatively (post-op), and at the first (D1) and second (D2) post-op day. AKI was defined as an increase of sCr to ≥1.5-fold from baseline within 2 days after surgery. Results: Of the 52 patients studied, 10 patients (19%) developed AKI. Patients with AKI were older (69.6 ± 10.7 vs. 58.1 ± 16.7 years, p = 0.043) and had a longer length of ICU stay (13 [IQR 6–49] vs. 6 [IQR 5–8] days, p = 0.032). Between the 2 groups, the evolution of BTP, sCr, CysC, and NGAL over time differed significantly, with overall higher values in the AKI group. ROC analysis for the detection of AKI within 2 days after surgery showed a great accuracy for BTP. The area under the curve (AUC) for BTP post-op; D1; and D2 was, respectively, 0.869 ± 0.049; 0.938 ± 0.035; and 0.943 ± 0.032. The discriminative power of a BTP measurement on D1 was superior in detecting AKI compared to NGAL (adjusted p value = 0.027). We could not detect a significant difference between the AUCs of other biomarkers (NGAL, sCr, and CysC). Conclusion: Serum BTP is a promising marker for diagnosing AKI in ICU patients undergoing surgery.

To investigate the role of neutrophil gelatinase-associated lipocalin in the evaluation of renal function, nutrition, anemia and inflammation in patients with chronic kidney diseases.A total of 302 patients with chronic kidney diseases were selected, and their clinical data, blood neutrophil gelatinase-associated lipocalin levels, renal function, nutrition, anemia, inflammation and calcium, and phosphorus metabolism were analyzed.Serum neutrophil gelatinase-associated lipocalin level increased with the progression of chronic kidney diseases. Higher neutrophil gelatinase-associated lipocalin levels were observed in patients with chronic kidney diseases stage 3b compared with healthy individuals (P0.05), while the patients with chronic kidney diseases stage 5 showed higher levels compared with other chronic kidney diseases stages (P0.01). Moreover, the ROC curve showed that neutrophil gelatinase-associated lipocalin had a better diagnostic performance from the chronic kidney diseases stage 3b to 5 (P0.05). In addition, the serum neutrophil gelatinase-associated lipocalin levels in patient with chronic kidney diseases were negatively correlated with body mass index, number of red blood cells, hemoglobin, transferrin, the estimatedglomerular filtration rate (eGFR), serum calcium (P0.01); and were positively correlated with mean arterial blood pressure, blood BUN, SCr and alpha 1 microglobulin, beta 2 microglobulin, urinary inhibition C, homocysteine, PTH levels, neutrophils ratio, free serum ferritin and c-reactive protein (P0.01); while no significant correlation was found with gender, and age (P0.05).Serum neutrophil gelatinase-associated lipocalin levels are closely related to renal function injury, inflammatory response and anemia-related indicators in patients with chronic kidney diseases, and thus could be used as a diagnostic biomarker for evaluating the degree of renal injury and related complications in patients with chronic kidney diseases.

LCN2 (Lipocalins) was first identified as iron transporter through associating with its siderophores and also involved in many cancer metastases, but its function is still paradoxical. We questioned that whether LCN2 might also associate exogenous iron chelator as does in inherent way and the association may influence their respective function. To address this issue, we investigated the effect of LCN2 on action of DpdtC (2,2′-dipyridine ketone hydrazone dithiocarbamte), an iron chelator in proliferation and metastasis-related gene expression. The results showed that exogenous LCN2 and DpdtC could inhibit growth of HepG2 cells, while the combination treatment enhanced their inhibitory effect both in proliferation and colony formation. This encouraged us to investigate the effect of the interaction on metastasis-related gene expression. The results revealed that both LCN2 and DpdtC impaired the wound healing of HepG2, but the inhibitory effect of DpdtC was significantly enhanced upon association with LCN2. Undergoing epithelium-mesenchymal transition (EMT) is a crucial step for cancer metastasis, LCN2 and DpdtC had opposite effects on EMT markers, the binding of DpdtC to LCN2 significantly weakened the regulation of it (or its iron chelate) on EMT markers. To insight into the interaction between LCN2 and DpdtC–iron, fluorescence titration and molecular docking were performed to obtain the association constant (~ 104 M−1) and thermodynamic parameters (ΔG = − 26.10 kJ/mol). Importantly this study provided evidence that siderophores-loading state of LCN2 may influence its function, which be helpful for understanding the contradictory role of LCN2 in the metastasis of cancer.

In patients with ST-elevation myocardial infarction (STEMI) the immune system is activated with an inflammatory response to follow. In STEMI patients with a severe inflammatory response, risk of development of cardiogenic shock (CS) seems increased. Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a glycoprotein released from mature neutrophils and plasma concentration may increase immediately after STEMI. We therefore aimed to assess whether admission NGAL plasma concentration in patients with STEMI was associated with CS development after leaving the catheterization laboratory (late CS) and 30-day all-cause mortality. PATIENTS AND METHODS: From 1,892 consecutive patients with STEMI 1,626 (86%) had plasma NGAL concentration measured upon hospital admission before angiography throughout a 1-year period at two tertiary heart centers in Denmark. Patients were stratified according to NGAL quartiles (Q1-4). To assess late CS development, we adjusted for the Observatoire Régional Breton sur l'Infarctus risk score for late CS. For mortality assessment, we adjusted for gender, age, post-PCI culprit Thrombolysis in myocardial infarction flow, left ventricular ejection fraction (LVEF), kidney dysfunction, and being comatose after cardiac arrest. RESULTS: Increasing NGAL concentration was associated with higher age, more comorbidities, and more critical patient conditions including lower blood pressure and LVEF. When adjusted for factors associated with poor outcome, NGAL remained independently associated with both late CS development (Q4 vs. Q1-3) (OR (95% CI) 3.64 (1.79-7.41) and 30-day mortality (HR (95% CI) 3.18 (1.73-5.84)). CONCLUSION: Admission plasma concentration of NGAL in STEMI patients is independently associated with 30-day all-cause mortality and predictive of late CS development.

Dienogest (DNG), is an effective and widely used progestin used in the treatment of endometriosis, yet clinically, a subset of cases show resistance to DNG treatment. During a previous investigation on the effect of DNG of cytokines and growth factor production, we incidentally found that endometriotic cyst fluid did not demonstrate inhibitory effects to DNG in a subset of cases. To clarify the mechanisms of this resistance to DNG, we performed proteomics analysis to compare the protein expression between DNG-sensitive and resistant cases. Based upon our results, several proteins were extracted that relate to neutrophil granulocyte activation marker (myeloperoxidase, lactotransferrin), inflammation (azurocidin, neutrophil gelatinase-associated lipocalin, etc.), and others biological processes reflecting the clinical environment of the endometriotic cyst. Among these proteins, azurocidin (AZU) is perhaps most interesting one as azurocidin is a protease that cleaves insulin-like growth factor-1 (IGFBP-1) associated with clear cell carcinoma of the ovary. We propose that the proteins extracted in the present study warrant further investigation in their relationship to carcinogenesis of endometrioma.

Background Acute myeloid leukemia (AML) is a malignancy arising within the bone marrow (BM), in which leukemic cells proliferate uncontrollably in association with a disruption of normal hematopoiesis.Aim of the work to evaluate the expression of LCN and BCL2L2, in newly diagnosed bone marrow samples from adult with AML and to correlate their expression levels with clinical and Laboratory data of the patients especially that known to have a prognostic feature. Methods This study was carried out on 87 consecutive newly diagnosed adult AML patients of which 75 are evaluated for both LCN, BCL2L12 (All 87 are evaluated for LCN). In addition, 20 donors of matched age and sex healthy individuals from donors for bone marrow transplantation were included as a control group. Results No statistical significant correlation was found between LCN over-expression and the control group , there was no statistical significance between its expression and age, sex, hepatomegally, splenomegally and lymphadenopathy, also there was no statistical significance regarding peripheral blood and bone marrow findings, immunophenotyping, cytogenetics or molecular findings and MRD at day 15.No statistical significance was found between BCL2L12 expression and the control group again there was no statistical significance between its expression and age, sex, hepatomegally, splenomegally and lymphadenopathy, also there was no statistical significance regarding peripheral blood and bone marrow findings, immunophenotyping, cytogenetics or molecular findings and MRD at day 15. Conclusion LCN and BCL2L12 were found to be expressed with non significant difference in AML as in normal subjects; however studies on large number of cases are needed to confirm our finding. The role of LCN and BCL2L12 need to be verified by further large-scale sample and further studies. .

Introduction It has been demonstrated that urinary neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin are helpful biomarkers in the differentiation of intrinsic and prerenal acute kidney injury. Objective The present cross-sectional study investigates, whether urinary biomarkers are able to differentiate primarily inflammatory from non-inflammatory entities in chronic kidney disease (CKD). Methods Urinary calprotectin, NGAL, and kidney injury molecule-1 (KIM-1) concentrations were assessed in a study population of 143 patients with stable CKD and 29 healthy controls. Stable renal function was defined as an eGFR fluctuation ≤5 ml/min/1.73 m2 in the past 12 months. Pyuria, metastatic carcinoma, and renal transplantation were regarded as exclusion criteria. Diabetic nephropathy, hypertensive nephropathy, and polycystic kidney disease were categorized as ‘primarily non-inflammatory renal diseases’ (NIRD), whereas glomerulonephritis and vasculitis were regarded as ‘primarily inflammatory renal diseases’ (IRD). Results Urinary calprotectin and NGAL concentrations significantly differed between CKD and healthy controls (p 0.05 each). Albumin exceeds the diagnostic power of the investigated biomarkers by far. Conclusions The urinary biomarkers calprotectin, NGAL, and KIM-1 have no diagnostic value in the differentiation of primarily inflammatory vs. non-inflammatory etiologies of CKD.

Many hypotheses underlie the pathogenesis of preeclampsia. This study aims to evaluate Neutrophil gelatinase-associated lipocalin (a marker of immune hypothesis) and Neutrophil / Lymphocyte ratio (a marker of inflammation) in the diagnosis of preeclampsia and its severity and to determine the correlation between them.Study design : This randomized case-control study involved 132 pregnant women ; 88 were diagnosed with PE (divided into non-severe and severe groups), and 44 healthy pregnant women as a control group. Results : The mean serum level of NGL was significantly higher in PE (535.37 ± 158.61 ng / ml for severe PE, 522.5 ± 106.3 ng / ml for non-severe PE, and 161.96 ± 17.48 ng / ml for the control group). The ROC Curve NGL criteria of more than 204.4 ng / ml showed 100% sensitivity and specificity in both severe and non-severe cases versus control. The N / L ratio showed a significant difference (5.81 ± 5.24 for severe PE, 4.1 ± 3.41 for non-severe PE, and 3.89 ± 1.79 for the control group), but the ROC curve criterion was not significant. Both showed a non-significant positive correlation. Conclusion : NGL is an excellent diagnostic factor, whereas N / L might have lower diagnostic performance compared with NGL. Both are related independently to the pathophysiology of PE. J. Med. Invest. 68 : 321-325, August, 2021.

Background/Aims: Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis, inflammation, hepatocellular injury, and fibrosis. We aimed to investigate the usefulness of a key biomarker, lipocalin-2 (LCN2), for the detection of NASH progression.Methods: A mouse NASH model was established using a high-fat diet and a high-sugar drinking water. Gene expression profile of the NASH model was analyzed using RNA sequencing. Moreover, 360 NAFLD patients (steatosis, 83; NASH, 277), 40 healthy individuals, and 87 patients with alcoholic fatty liver disease were recruited.Results: Inflammatory infiltration, focal necrosis in the leaflets, steatosis, and fibrosis were documented in the mouse liver. In total, 504 genes were differentially expressed in the livers of NASH mice, and showed significant functional enrichment in the inflammation-related category. Upregulated liver LCN2 was found to be significantly interactive with various interleukins and toll-like receptors. Serum LCN2 levels were significantly increased in NAFLD patients. Serum LCN2 levels were correlated with steatosis, intralobular inflammation, semiquantitative fibrosis score, and nonalcoholic fatty liver disease activity score. The area under the curve of serum LCN2 was 0.987 with a specificity of 100% and a sensitivity of 93.5% for NASH diagnosis, and 0.977 with almost the same specificity and sensitivity for steatosis.Conclusions: LCN2 might be involved in the transition from NAFL to NASH by mediating inflammation. Serum LCN2 levels might be a novel biomarker for the diagnosis of NASH.

Myocardial infarction (MI) is associated with renal alterations resulting in poor outcomes in patients with MI. Renal fibrosis is a potent predictor of progression in patients and is often accompanied by inflammation and oxidative stress; however, the mechanisms involved in these alterations are not well established. Endoplasmic reticulum (ER) plays a central role in protein processing and folding. An accumulation of unfolded proteins leads to ER dysfunction, termed ER stress. Since the kidney is the organ with highest protein synthesis fractional rate, we herein investigated the effects of MI on ER stress at renal level, as well as the possible role of ER stress on renal alterations after MI. Patients and MI male Wistar rats showed an increase in the kidney injury marker neutrophil gelatinase-associated lipocalin (NGAL) at circulating level or renal level respectively. Four weeks post-MI rats presented renal fibrosis, oxidative stress and inflammation accompanied by ER stress activation characterized by enhanced immunoglobin binding protein (BiP), protein disulfide-isomerase A6 (PDIA6) and activating transcription factor 6-alpha (ATF6α) protein levels. In renal fibroblasts, palmitic acid (PA; 50-200 µM) and angiotensin II (Ang II; 10−8 to 10−6M) promoted extracellular matrix, superoxide anion production and inflammatory markers up-regulation. The presence of the ER stress inhibitor, 4-phenylbutyric acid (4-PBA; 4 µM), was able to prevent all of these modifications in renal cells. Therefore, the data show that ER stress mediates the deleterious effects of PA and Ang II in renal cells and support the potential role of ER stress on renal alterations associated with MI.

Purpose of review Urinary biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and N-acetyl-B-D-glucosamindase (NAG) are recognised as being useful for the detection of kidney tubular damage but their role in the diagnosis and prognosis of kidney stone disease (KSD) is still unknown. To clarify this, we performed a systematic review of literature in accordance with Cochrane methodology from inception to September 2020. Recent findings Twelve studies were included and a variety of urinary biomarkers (KIM-1, NGAL, NAG, proteins/peptides, cytokines, CA19-9) were measured in a total of 998 patients with KSD. Despite some contradicting studies, majority of the biomarkers studied showed a significant rise in patients with KSD compared to healthy controls, with levels decreasing after their surgical management, noticed as early as 4 h postprocedure. There was limited evidence of correlation with stone burden and elevated levels were also associated with hydronephrosis and superimposed infections. Summary Urinary biomarkers could be used in the diagnosis, prognosis and stone-treatment response in patients with KSD. However, as novel indicators, they may not be reliable as the sole diagnostic or prognostic tool for KSD as they are readily confounded by other causes of kidney injury. Further studies are needed to determine their ability to separate KSD from other causes of obstructive uropathy and acute renal injury.

Novel urinary protein biomarkers have recently been identified and qualified in rats for the early detection of renal injury in drug development studies. However, there are few reports on the utility of these renal biomarkers in mice, another important and widely used preclinical animal species for drug development studies. The purpose of this study was to assess the value of these recently qualified biomarkers for the early detection of drug-induced kidney injury (DIKI) in different strains of mice using multiple assay panels. To this end, we evaluated biomarker response to kidney injury induced by several nephrotoxic agents including amphotericin B, compound X, and compound Y. Several of the biomarkers were shown to be sensitive to DIKI in mice. When measured, urinary albumin and neutrophil gelatinase-associated lipocalin were highly sensitive to renal tubular injury, regardless of the assay platforms, mouse strain, and nephrotoxic agents. Depending on the type of renal tubular injury, kidney injury molecule-1 was also highly sensitive, regardless of the assay platforms and mouse strain. Osteopontin and cystatin C were modestly to highly sensitive to renal tubular injury, but the assay type and/or the mouse strain should be considered before using these biomarkers. Calbindin D28 was highly sensitive to injury to the distal nephron in mice. To our knowledge, this is the first report that demonstrates the utility of novel urinary biomarkers evaluated across multiple assay platforms and nephrotoxicants in different mice strains with DIKI. These results will help drug developers make informed decisions when selecting urinary biomarkers for monitoring DIKI in mice for toxicology studies.

Aim: An advanced proteomics platform for protein biomarker discovery in diabetic chronic kidney disease (DKD) was developed, validated and implemented. Materials & methods: Three Type 2 diabetes mellitus patients and three control subjects were enrolled. Urinary peptides were extracted, samples were analyzed on a hybrid LTQ-Orbitrap Velos Pro instrument. Raw data were searched using the SEQUEST algorithm and integrated into Proteome Discoverer platform. Results & discussion: Unique peptide sequences, resulted sequence coverage, scoring of peptide spectrum matches were reported to albuminuria and databases. Five proteins that can be associated with early DKD were found: apolipoprotein AI, neutrophil gelatinase-associated lipocalin, cytidine deaminase, S100-A8 and hemoglobin subunit delta. Conclusion: Urinary proteome analysis could be used to evaluate mechanisms of pathogenesis of DKD.

Objectives Elevated neutrophil gelatinase-associated lipocalin (NGAL) is a promising marker for severe acute pancreatitis (SAP) and multiple organ failure, suggesting systemic and local contributions during pancreatitis. We investigated the role of NGAL locally on acinar cell biology. Methods Western blot, reverse transcriptase-polymerase chain reaction, and immunohistochemistry analysis were performed to analyze the levels of NGAL receptors, apoptotic and regeneration markers, and 4-hydroxynonenal (4HNE) levels, 3-[4,5-Dimethylthiazole-2-yl]-2, 5-diphenyltetrazolium bromide assay, and annexin V/propidium iodide staining were used to evaluate cell viability, and effect on endothelial cells was accessed by endothelial permeability assay. Results Cerulein treatment at 20 μM for 12 hours significantly reduced acinar cell viability by 40%, which was rescued by NGAL at 800 and 1600 ng/mL concentrations, observed during mild and SAP, respectively. Mechanistically, NGAL significantly reduced the levels of reactive oxygen species and 4HNE adduct formation in a 24p3R-dependent manner and upregulated the expression of acinar cell regeneration markers, like CDK-2, CDK-4, and C-myc. However, SAP levels of NGAL significantly increased endothelial permeability and downregulated the levels of ZO-1, and cerulein treatment in NGAL knockout mice showed increased levels of 4HNE adducts. Conclusions Neutrophil gelatinase-associated lipocalin rescues intracellular reactive oxygen species during pancreatitis and promotes survival and regeneration of acinar cells.

OBJECTIVE To evaluate the clinical significance of serum and urinary microRNA-423-5p in the prediction of acute kidney injury onset and survival in patients with acute decompensated heart failure. METHODS A total of 180 acute decompensated heart failure patients, including 57 acute kidney injury cases and 123 non-acute kidney injury cases, were included in this study. Serum and urinary neutrophil gelatinase-associated lipocalin, a biomarker of renal injury of acute kidney injury, was detected using an enzyme-linked immunosorbent assay. Expression of microRNA-423-5p in serum and urine samples was examined using quantitative real-time polymerase chain reaction. The clinical significance of microRNA-423-5p was evaluated using receiver operating characteristic curve and Kaplan-Meier survival analysis. RESULTS The levels of neutrophil gelatinase-associated lipocalin and microRNA-423-5p in serum and urine samples were elevated in patients with acute kidney injury compared with the non-acute kidney injury cases (all P

Although some progress has been achieved in understanding certain aspects of the allergenic mechanism of animal lipocalins, they still remain largely enigmatic. One possibility to unravel this property is to investigate their interaction with components of the immune system. Since these components are highly complex we intended to use a high-throughput technology for this purpose. Therefore, we used phage-display of a random peptide library for panning against the dog allergen Can f 1. By this method we identified a Can f 1 binding peptide corresponding to the antigen-binding site of a putative γδT-cell receptor. Additional biochemical investigations confirmed this interaction.

To evaluate and compare the efficacy of urinary carbohydrate antigen 19-9 (CA19-9), neutrophil gelatinase–associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1) biomarkers as predictive factors to determine the surgery requirement in patients with ureteropelvic junction obstruction. We obtained urine samples from 161 patients at diagnosis and evaluated their levels of the three biomarkers. The patients were under observation for 2 years; subsequently, they were divided into two groups based on their requirement of pyeloplasty. We determined the correlation between the urinary concentration of the biomarkers and surgical interventions, as well as the kidney function deterioration and sonography outcomes. The non-surgery group included 60 male and 22 female patients with mean age of 21 months. The surgery group comprised 58 boys and 21 girls with mean age of 26.9 months with no significant difference of age and gender between the two groups. The outcomes were indicative of higher efficacy of CA19-9 level with a sensitivity and specificity of 84.2% and 73.2% at the cutoff point of 59.09 U/ml. Also, a significant negative correlation was detected between the kidney function and the concentrations of CA19-9 and NGAL. Our evaluations demonstrate the higher efficacy of CA19-9 to predict the requirement of surgical intervention in comparison with the other biomarkers, as well as a significant correlation between kidney function deterioration and urinary CA19-9 and NGAL. The outcomes of this investigation could pave the way for more extensive clinical application of these urinary biomarkers, besides future research determining the association between markers and kidney fibrosis.

OBJECTIVE To screen for the presence of biomarkers involved in tubular injury and kidney damage in children with urolithiasis (RS), and to validate these proteins by ELISA. METHODS Prospective-controlled pilot study of children with urolithiasis and their age- and gender-matched controls (HC). Initial screening test was done by quantitative proteomic comparison of pooled urine from RS versus HC, using liquid chromatography-mass spectrometry. Proteins of interest were selected using the following criteria: (1) ≥5 spectral counts; (2) ≥2-fold difference in spectral counts; and (3) ≤.05 P value for the Fisher's Exact Test. Validation was performed by ELISA testing. Statistical analysis was performed by Student t-test and Mann-Whitney U test. RESULTS Proteomic analysis identified 3 proteins of interest, Cystatin C (CYTC), neutrophil gelatinase-associated lipocalin (NGAL) and lysozyme C that were significantly over-represented in RS group versus HC. ELISA analysis revealed significantly increased urinary levels of CYTC and NGAL, and nearly significantly increased urinary levels of lysozyme C in RS group (N = 24) compared to controls (N = 13). Subgroup analysis showed significantly higher urinary levels of CYTC in both hypercalciuria (N = 14) and hypocitraturia (N = 10) versus HC (P CONCLUSION Children with urolithiasis showed significant increase in urinary CYTC and NGAL irrespective of their normal serum creatinine. These biomarkers indicate tubular injury and early kidney damage and represent valid tools for early screening when traditional tests are normal.

Advanced fibrosis and portal hypertension influence short-term mortality. Lipocalin 2 (LCN2) regulates infection response and increases in liver injury. We explored the role of intrahepatic LCN2 in human alcoholic hepatitis (AH) with advanced fibrosis and portal hypertension and in experimental mouse fibrosis. We found hepatic LCN2 expression and serum LCN2 level markedly increased and correlated with disease severity and portal hypertension in patients with AH. In control human livers, LCN2 expressed exclusively in mononuclear cells, while its expression was markedly induced in AH livers, not only in mononuclear cells but also notably in hepatocytes. Lcn2−/− mice were protected from liver fibrosis caused by either ethanol or CCl4 exposure. Microarray analysis revealed downregulation of matrisome, cell cycle and immune related gene sets in Lcn2−/− mice exposed to CCl4, along with decrease in Timp1 and Edn1 expression. Hepatic expression of COL1A1, TIMP1 and key EDN1 system components were elevated in AH patients and correlated with hepatic LCN2 expression. In vitro, recombinant LCN2 induced COL1A1 expression. Overexpression of LCN2 increased HIF1A that in turn mediated EDN1 upregulation. LCN2 contributes to liver fibrosis and portal hypertension in AH and could represent a new therapeutic target.

Background. To evaluate the ratio of acute kidney injury (AKI) to chronic kidney disease (CKD) in sepsis-associated acute kidney injury (SA-AKI) patients of the intensive care unit (ICU) and predictive value of neutrophil gelatinase-associated lipocalin (NGAL) measured at the admission time in the progression of AKI to CKD. Methods. A study of 121 consecutive adult patients admitted to the intensive care unit (ICU) diagnosed as SA-AKI. AKI and CKD were defined based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Glomerular filtration rate (GFR) was calculated by the CKD-EPI formula. Serum and urine NGAL was measured using the BioVendor Human Lipocalin-2/NGAL ELISA with a blood sample taken at hospital admission time. Results. The ratio of AKI to CKD in SA-AKI patients was 22.3%. Mean concentration of serum and urine NGAL in AKI to the CKD group was 790.99 ng/ml and 885.72 ng/ml, higher significantly than those of recovery patients (351.86 ng/ml and 264.68 ng/ml), p<0.001. eGFR, both serum and urine NGAL had a predictive value for AKI to CKD (eGFR: AUC=0.857, Se=74.1%, Spe=92.6%, p<0.001. Serum NGAL: AUC=0.868, Se=77.8%, Spe=91.5%. Urine NGAL: AUC=0.869, Se=77.8%, Spe=92.6%, p<0.001. Conclusion. Serum and urine NGAL, measuring at hospital admission time, were good prognostic biomarkers of AKI to CKD in SA-AKI patients.

Objective Liver damage is a common manifestation and can be life-threatening in adult-onset Still’s disease (AOSD), an autoinflammatory disease. The hallmark of AOSD is activation of neutrophils, whose infiltration in liver is suspected to promote tissue injury. Here we aimed to identify a candidate biomarker and to validate its association with liver damage in AOSD. Methods Transcriptome analysis of neutrophils from treatment-naïve active AOSD patients and healthy donors was performed. Lipocalin-2 (LCN2) expression was assessed in neutrophils, plasma and liver biopsies of AOSD. The correlations of LCN2 with different variables and its ability to identify liver damage from AOSD patients were analysed. Results LCN2, a novel biomarker in hepatic inflammation, was found to be upregulated in AOSD neutrophils by RNA sequencing and confirmed at the mRNA and protein levels. Plasma levels of LCN2 were significantly higher in AOSD patients than healthy controls, RA and SLE patients. Plasma LCN2 levels were closely correlated with inflammatory markers, systemic score, HScore and cytokines. Moreover, LCN2 levels were increased in active AOSD with liver involvement and independently associated with liver dysfunction. Enhanced expression of LCN2 was detected in liver biopsies from three patients with ongoing liver injury. Furthermore, the area under the curve value of LCN2 for identifying AOSD with liver injury from other liver diseases was 0.9694. Conclusion Our results reveal that neutrophils-derived LCN2 is higher in plasma and liver tissue in AOSD patients than in healthy controls, and it could serve as a potent biomarker for identifying AOSD with systemic inflammation, especially liver damage caused by hyperinflammation.

Hypertension and chronic kidney disease (CKD) are serious interrelated public health problems. Despite the monitoring and control of high blood pressure, symptoms of CKD are not usually apparent in its early stages. Previously, we reported the utility of urinary vanin‐1 as an early biomarker of kidney injury in spontaneously hypertensive rats, but it remains unknown whether urinary vanin‐1 is associated with CKD in humans. In this study, we estimated associations between urinary vanin‐1 and parameters of kidney function in a cross‐sectional study of hypertensive patients. We measured concentrations of vanin‐1 using spot urine from 147 adult hypertensive patients (mean age, 72.8 years; 39.5% women). Patients were divided into 2 groups based on the median of the estimated glomerular filtration rate (eGFR). The group with eGFR

OBJECTIVE The aim of this study was to investigate the clinical course, selected biochemical parameters and concentrations of renal injury biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and liver-fatty acid binding protein (L-FABP) in patients with immunoglobulin A vasculitis (IgAV) to identify the markers associated with nephritis in the course of the disease (IgAVN). METHODS The study involved 29 children with IgAV and 34 healthy controls. Eleven (38%) patients had renal involvement (IgAV-N) and 18 (62%) did not exhibit nephritis (IgAV-noN). Initial laboratory tests, determining the concentrations of NGAL, KIM-1 and L-FABP in serum and urine, were conducted on children from the study group in an acute phase of IgAV as well as after an average of 6 months, during a follow-up visit. The interconnection between renal involvement, anthropometric measurements, epidemiological data, laboratory parameters and levels of examined biomarkers have been thoroughly evaluated. RESULTS The serum and urine levels of NGAL, KIM-1 and L-FABP were significantly higher in children with an acute phase of IgAV as compared to the control group (P

Background/aim In recent years, the diagnostic utility of urinary protein levels has been demonstrated for the early detection and progression of kidney disease. This study aimed to evaluate the associations of the non-albumin protein (NAP) with different urinary marker for tubular and glomerular damage in patients with type 2 diabetes (T2D). Methods In this observational cross-sectional study, 424 patients with T2D duration > 10 years were classified into two groups according to estimated glomerular filtration rate (eGFR). The ratios of different urinary markers (albumin, NAP, total protein, transferrin, retinol-binding protein (RBP), and neutrophil gelatinase-associated lipocalin (NGAL) to creatinine were analyzed. Results The levels of urinary biomarkers increased significantly with decrease in eGFR levels. In the group with moderately decreased eGFR, the albumin to-creatinine ratio (ACR), non-albumin protein-to-creatinine ratio (NAPCR), and total protein-to-creatinine ratio (PCR) were independently associated with all urinary markers after being adjusted for risk factors. The area under the receiver operating characteristics (ROC) curve for ACR and PCR had a better diagnostic value than other urinary biomarkers. Comparing ROC curve of NAPCR with other urinary biomarkers, it was significantly better than NGAL/Cr (p = 0.033). Conclusions The findings of the present study confirm that ACR and PCR are diagnostic biomarkers in T2D patients with decreased eGFR. NAPCR in these patients diagnostically only outperformed NGAL/Cr.

Significance Molecular ON-switches are important tools in chemical biology, enabling protein–protein interactions to be regulated by small molecules. However, currently available ON-switches that induce conditional heterodimerization are suboptimal for therapeutic applications. In this study, we present an ON-switch system based on human retinol binding protein 4 (hRBP4) and the orally available small molecule A1120. Two distinct protein scaffolds, FN3 and rcSso7d, were successfully engineered to bind to hRBP4 in a small molecule-dependent manner, demonstrating the flexibility of the system. The binders specifically associated with the drug-induced conformation of hRBP4. Our study demonstrates that lipocalin-based ON-switches can enable specific regulation of protein heterodimerization and provides proof of concept for potential applications in controlling the activity of human CAR T cells., Molecular ON-switches in which a chemical compound induces protein–protein interactions can allow cellular function to be controlled with small molecules. ON-switches based on clinically applicable compounds and human proteins would greatly facilitate their therapeutic use. Here, we developed an ON-switch system in which the human retinol binding protein 4 (hRBP4) of the lipocalin family interacts with engineered hRBP4 binders in a small molecule-dependent manner. Two different protein scaffolds were engineered to bind to hRBP4 when loaded with the orally available small molecule A1120. The crystal structure of an assembled ON-switch shows that the engineered binder specifically recognizes the conformational changes induced by A1120 in two loop regions of hRBP4. We demonstrate that this conformation-specific ON-switch is highly dependent on the presence of A1120, as demonstrated by an ∼500-fold increase in affinity upon addition of the small molecule drug. Furthermore, the ON-switch successfully regulated the activity of primary human CAR T cells in vitro. We anticipate that lipocalin-based ON-switches have the potential to be broadly applied for the safe pharmacological control of cellular therapeutics.

Background The exact mechanisms underlying neuroinflammation and how they contribute to amyotrophic lateral sclerosis (ALS) pathogenesis remain unclear. One possibility is the secretion of neurotoxic factors, such as lipocalin-2 (LCN2), that lead to neuronal death. Methods LCN2 levels were measured in human postmortem tissue using Western blot, quantitative real time polymerase chain reaction, and immunofluorescence, and in plasma by enzyme-linked immunosorbent assay. SH-SY5Y cells were used to test the pro-inflammatory effects of LCN2. Results LCN2 is increased in ALS postmortem motor cortex, spinal cord, and plasma. Furthermore, we identified several LCN2 variants in ALS patients that may contribute to disease pathogenesis. Lastly, while LCN2 treatment caused cell death and increased pro-inflammatory markers, treatment with an anti-LCN2 antibody prevented these responses in vitro. Conclusions LCN2 upregulation in ALS postmortem samples and plasma may be an upstream event for triggering neuroinflammation and neuronal death.

Background/aims Urinary tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been recently discovered and validated as sensitive biomarkers that can predict stage 2 or 3 acute kidney injury (AKI) development in high-risk patients. We aimed to assess whether these biomarkers could predict adverse outcomes and renal recovery in established AKI patients. Methods This was a single-center study prospectively enrolling 124 patients diagnosed with AKI. TIMP-2, IGFBP7, neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule 1 (KIM-1) levels were measured at the time of diagnosis and the predictive performance of short-term outcomes and renal recovery was assessed. Results Patients were divided into 4 quartiles according to the initial urinary TIMP-2/IGFBP7 levels. Stage 3 AKI (odds ratio [OR], 17.86), classified by the Kidney Disease Improving Global Outcomes (KDIGO), as well as the third and fourth quartiles of TIMP-2/IGFBP7 (OR, 5.75 and 44.98, respectively), were found to be independent predictors of renal replacement therapy at the time of AKI diagnosis. In addition, KDIGO stage 3 AKI (OR, 2.468) or the third of fourth quartiles of urinary TIMP-2/IGFBP7 (OR, 1.896 and 3.622, respectively) were also found to be useful in predicting nonrecovery of renal function. In a separate analysis of patients with renal recovery at discharge, initial urinary TIMP-2/IGFBP7 or urinary IGFBP7 at discharge could also predict new-onset or progressive chronic kidney disease (CKD). Conclusion In AKI patients, urine TIMP-2/IGFBP7 could serve as a biomarker for predicting adverse outcomes, renal recovery, or the development and progression of CKD.

Background Urinary neutrophil gelatinase-associated lipocalin is an established biomarker of acute kidney injury, however, the levels are affected by the number of white blood cells in the urine. As we suspected the portion of the urinary stream sampled could also have a significant influence on the urinary NGAL levels in female subjects, we investigated the influence of the urine sampling procedure on the urinary NGAL levels. Methods We collected 25-mL urinary specimens from each of initial-stream and midstream urinary specimens, including 28 healthy adult female volunteers without kidney diseases or UTI. Then we compared the WBC count, NGAL level, and creatinine level between these specimens. Results We observed that the urinary NGAL levels were significantly higher in the specimens obtained from initial-stream urinary samples than in midstream specimens, and that they were strongly correlated with the leukocyte esterase activity and WBC count. Moreover, the differences in the urinary NGAL levels between the initial- and midstream urine samples were greater for initial-stream samples with higher leukocyte esterase activities, with a significant difference even for the initial-stream samples with no detectable leukocyte esterase activity. Conclusion Therefore, midstream urine sampling is strongly recommended for accurate measurement of the urinary NGAL levels.

BACKGROUND AND OBJECTIVES: Oxidative stress is a hallmark and mediator of CKD. Diminished antioxidant defenses are thought to be partly responsible. However, there is currently no way to prospectively assess antioxidant defenses in humans. Tin protoporphyrin (SnPP) induces mild, transient oxidant stress in mice, triggering increased expression of select antioxidant proteins (e.g., heme oxygenase 1 [HO-1], NAD[P]H dehydrogenase [quinone] 1 [NQO1], ferritin, p21). Hence, we tested the hypothesis that SnPP can also variably increase these proteins in humans and can thus serve as a pharmacologic “stress test” for gauging gene responsiveness and antioxidant reserves. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A total of 18 healthy volunteers and 24 participants with stage 3 CKD (n=12; eGFR 30–59 ml/min per 1.73 m(2)) or stage 4 CKD (n=12; eGFR 15–29 ml/min per 1.73 m(2)) were injected once with SnPP (9, 27, or 90 mg). Plasma and/or urinary antioxidant proteins were measured at baseline and for up to 4 days post-SnPP dosing. Kidney safety was gauged by serial measurements of BUN, creatinine, eGFR, albuminuria, and four urinary AKI biomarkers (kidney injury molecule 1, neutrophil gelatinase-associated lipocalin, cystatin C, and N-acetyl glucosaminidase). RESULTS: Plasma HO-1, ferritin, p21, and NQO1 were all elevated at baseline in CKD participants. Plasma HO-1 and urine NQO1 levels each inversely correlated with eGFR (r=−0.85 to −0.95). All four proteins manifested statistically significant dose- and time-dependent elevations after SnPP injection. However, marked intersubject differences were observed. p21 responses to high-dose SnPP and HO-1 responses to low-dose SnPP were significantly suppressed in participants with CKD versus healthy volunteers. SnPP was well tolerated by all participants, and no evidence of nephrotoxicity was observed. CONCLUSIONS: SnPP can be safely administered and, after its injection, the resulting changes in plasma HO-1, NQO1, ferritin, and p21 concentrations can provide information as to antioxidant gene responsiveness/reserves in subjects with and without kidney disease. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: A Study with RBT-1, in Healthy Volunteers and Subjects with Stage 3–4 Chronic Kidney Disease, NCT0363002 and NCT03893799

The study aim is to determine whether serum and urine interleukin-6 (IL-6) and neutrophil gelatinase-associated lipocalin (NGAL) can be included in the early diagnostic algorithm for pediatric appendicitis. Prospective single-center cohort study included 92 children divided into control, acute complicated appendicitis (AcA) and acute uncomplicated appendicitis (AnA) groups. Serum and urine samples were assayed for IL-6 and NGAL preoperatively, and on the second and fifth postoperative days. Intraoperative and bacteriological findings divided the appendicitis patients. Average serum biomarker levels were higher in appendicitis patients versus the control, and the following values were produced via receiver operating characteristic (ROC) analysis. NGAL and IL-6 cutoff values were 113.95 ng/ml and 24.64 pg/ml, respectively, NGAL had 68.3% sensitivity and 65.5% specificity, while IL-6 had 72.6% and 86.2%. Comparing AcA and AnA, IL-6 was the only biomarker of significance yielding 77.4% sensitivity and 58.1% specificity with a 26.43 pg/ml cutoff value. Urine biomarkers were non-specific in differentiation appendicitis severity and ultimately, between infectious and non-infectious disease. Although NGAL provided measurable useful diagnostic information in evaluating children for appendicitis, its values were not sufficient for appendicitis severity. Serum IL-6 remains a strong biomarker for suspected acute appendicitis and has promising results predicting its severity.

Lipocalin-2 (LCN2) is a secreted glycoprotein involved in several chronic inflammatory processes. Metabolic syndrome (MetS) and adult growth hormone deficiency (GHD) are known as chronic inflammatory conditions. The primary objective of this observational cross-sectional study was to compare LCN2 plasmatic levels in these clinical settings, whereas the secondary objective was to investigate any possible correlation between LCN2 and BMI and/or indexes of insulin sensitivity/resistance. Seventy-four patients were divided as follows: Group A, MetS (18 patients, 13 females and 5 males, mean ± SEM age 45.1 ± 4.11 years, BMI 31.22 ± 1.73 kg/m2 ); Group B, total GHD (18 patients, 8 females and 10 males, age 52.44 ± 2.61 years, BMI 30.49 ± 1.87 kg/m2 ); Group C, Partial GHD (pGHD; 19 patients, 13 females and 6 males, age 48.63 ± 2.19 years, BMI 29.11 ± 1.85 kg/m2 ); Group D, Controls (19 patients, 13 females and 6males, age 40.26 ± 2.87 years, BMI 23.25 ± 0.95 kg/m2 ). They were evaluated for glucose and insulin, HOMA-index, QUICKI-index, Total/low-density lipoprotein/high-density lipoprotein cholesterol, triglycerides, uric acid, IGF-1, and LCN2. LCN2 plasmatic levels were significantly increased in MetS, while no significant differences with controls were found in total and pGHD. LCN2 levels did not correlate with BMI. A significant positive correlation between LCN2 and HOMA-index was found in controls, while a trend-like, yet not significant, a positive correlation was observed in pGHD. Our data show an increase in LCN2 plasmatic levels in MetS. Different inflammatory patterns characterize MetS and GHD. The correlation between HOMA index and LCN2 in normal subjects and possibly in pGHD ones suggests a modulatory action of LCN2 on insulin resistance.

Background The ability of urinary biomarkers to complement established clinical risk prediction models for postoperative adverse kidney events is unclear. We assessed the effect of urinary biomarkers linked to suspected pathogenesis of cardiac surgery-induced acute kidney injury (AKI) on the performance of the Cleveland Score, a risk assessment model for postoperative adverse kidney events. Methods This pilot study included 100 patients who underwent open-heart surgery. We determined improvements to the Cleveland Score when adding urinary biomarkers measured using clinical laboratory platforms (neutrophil gelatinase-associated lipocalin [NGAL], interleukin-6) and those in the preclinical stage (hepcidin-25, midkine, alpha-1 microglobulin), all sampled immediately post-surgery. The primary endpoint was major adverse kidney events (MAKE), and the secondary endpoint was AKI. We performed ROC curve analysis, assessed baseline model performance (odds ratios [OR], 95% CI), and carried out statistical reclassification analyses to assess model improvement. Results NGAL (OR [95% CI] per 20 concentration-units wherever applicable): (1.07 [1.01-1.14]), Interleukin-6 (1.51 [1.01-2.26]), midkine (1.01 [1.00-1.02]), 1-hepcidin-25 (1.08 [1.00-1.17]), and NGAL/hepcidin-ratio (2.91 [1.30-6.49]) were independent predictors of MAKE and AKI (1.38 [1.03-1.85], 1.08 [1.01-1.15], 1.01 [1.00-1.02], 1.09 [1.01-1.18], and 3.45 [1.54-7.72]). Category-free net reclassification improvement identified interleukin-6 as a model-improving biomarker for MAKE and NGAL for AKI. However, only NGAL/hepcidin-25 improved model performance for event- and event-free patients for MAKE and AKI. Conclusions NGAL and interleukin-6 measured immediately post cardiac surgery may complement the Cleveland Score. The combination of biomarkers with hepcidin-25 may further improve diagnostic discrimination.