Interleukin (IL) 16: a candidate urinary biomarker for proliferative lupus nephritis

Identification of molecular and cellular infection response biomarkers associated with anthrax infection through comparative analysis of gene expression data

Bacillus anthracis, a gram-positive bacillus capable of forming spores, causes anthrax in mammals, including humans, and is recognized as a potential biological weapon agent. The diagnosis of anthrax is challenging due to variable symptoms resulting from exposure and infection severity. Despite the availability of a licensed vaccines, their limited long-term efficacy underscores the inadequacy of current human anthrax vaccines, highlighting the urgent need for next-generation alternatives. Our study aimed to identify molecular biomarkers and essential biological pathways for the early detection and accurate diagnosis of human anthrax infection. Using a comparative analysis of Bacillus anthracis gene expression data from the Gene Expression Omnibus (GEO) database, this cost-effective approach enables the identification of shared differentially expressed genes (DEGs) across separate microarray datasets without additional hybridization. Three microarray datasets (GSE34407, GSE14390, and GSE12131) of B. anthracis-infected human cell lines were analyzed via the GEO2R tool to identify shared DEGs. We identified 241 common DEGs (70 upregulated and 171 downregulated) from cell lines treated similarly to lethal toxins. Additionally, 10 common DEGs (5 upregulated and 5 downregulated) were identified across different treatments (lethal toxins and spores) and cell lines. Network meta-analysis identified JUN and GATAD2A as the top hub genes for overexpression, and NEDD4L and GULP1 for underexpression. Furthermore, prognostic analysis and SNP detection of the two identified upregulated hub genes were carried out in conjunction with machine learning classification models, with SVM yielding the best classification accuracy of 87.5 %. Our comparative analysis of Bacillus anthracis infection revealed striking similarities in gene expression 241 profiles across diverse datasets, despite variations in treatments and cell lines. These findings underscore how anthrax infection activates shared genes across different cell types, emphasizing this approach in the discovery of novel gene markers. These markers offer insights into pathogenesis and may lead to more effective therapeutic strategies. By identifying these genetic indicators, we can advance the development of precise immunotherapies, potentially enhancing vaccine efficacy and treatment outcomes.

Systemic inflammatory regulators are associated with two common types of neuropathic pain: A bidirectional Mendelian randomization study

BACKGROUND

Currently, there is limited and inconsistent evidence regarding the causal relationship between systemic inflammatory regulators and two common types of neuropathic pain, namely, postherpetic neuralgia (PHN) and trigeminal neuralgia (TN). This study employed a Mendelian randomization (MR) approach to investigate the causal relationship between systemic inflammatory regulators and these two common neuropathic pain conditions.

METHODS

In this study, 41 single-nucleotide polymorphisms (SNPs) associated with PHN and TN were selected as instrumental variables (IVs) representing systemic inflammatory regulators. Genetic associations of systemic inflammatory regulators were derived from recent genome-wide association studies (GWAS) on the human proteome and cytokines. Genetic data related to PHN and TN were obtained from the FinnGen. The primary analytical method utilized inverse variance weighting (IVW) and various sensitivity analyses.

RESULTS

Prior to applying the false discovery rate (FDR) correction, our bidirectional MR analysis revealed that increased levels of IFNγ (OR: 0.46, 95% CI: 0.24-0.87, PIVW: 0.016) and MCP3 (OR: 0.52, 95% CI: 0.35-0.77, PIVW: 0.001) were associated with a reduced risk of PHN, and increased levels of IL-16 (OR: 0.81, 95% CI: 0.67-0.98, PIVW: 0.026) were causally associated with a reduced risk of TN. In discussing the impact of PHN and TN on systemic inflammatory regulator levels, we observed the following findings: The BETA for CTACK was -0.07 (95% CI: -0.13 to -0.01, PIVW: 0.015), the BETA for FGFBasic was -0.04 (95% CI: -0.08 to -0.01, PIVW: 0.020), and the BETA for IL-17 was -0.04 (95% CI: -0.08 to -0.01, PIVW: 0.019). These results indicate that patients with PHN tend to have lower levels of CTACK, FGFBasic, and IL-17. Conversely, the BETA for IFNγ was -0.09 (95% CI: -0.18 to 0.00, PIVW: 0.046), suggesting that patients with TN tend to have lower levels of IFN γ. However, after FDR correction, only the association between MCP3 and PHN remained statistically significant (PFDR: 0.044).

CONCLUSION

This study found that certain systemic inflammatory regulators are associated with PHN and TN to some extent. However, further research is needed to explore the specific mechanisms underlying these connections.

Dynamics of scFv-targeted VAP2 correlating with IL-16, MIF and IL-1Ra in ANCA-associated vasculitis

BACKGROUND AND HYPOTHESIS

Using a mouse model of MPA with microvascular lesion with a clone (VasSF) of recombinant single chain fragments of the variable region of human IgG, we previously showed that vasculitis-associated apolipoprotein A2 (VAP2) may be a therapeutic target for vasculitis. The present study estimated the target molecules for VasSF and the association between VAP2 and cytokine levels in patient sera in terms of microvascular lesion severity.

METHODS

Sera and clinical information were collected from patients with microscopic polyangiitis and granulomatosis with polyangiitis (MPA/GPA) and infectious disease. Neutrophil counts, levels of C-reactive protein (CRP), creatinine, total cholesterol associated with microvascular lesion, HDL cholesterol, low-density lipoprotein cholesterol, triglycerides, glomerular filtration rate (eGFR), and cytokines were estimated. Serum VAP2 signals were determined with Western blotting.

RESULTS

VasSF bound to a 24 kDa molecule in the serum of active MPA/GPA patients. Anti-AP2 antibody also bound with the same 24 kDa molecule, named VAP2, because of size difference from normal APOA2. The VAP2 signal was significantly stronger in the active-disease group but significantly weakened in remission. The signal correlated positively with eGFR but not with the Birmingham Vasculitis Activity Score, CRP, MPO-ANCA, or PR3-ANCA levels. It correlated negatively with MPO activity, IL-16, MIF, and IL-1Ra. Moreover, VasSF bound to a 17 kDa molecule in the remission phase.

CONCLUSION

The 24 kDa VAP2 molecule may be associated with neutrophil functions because of its inverse correlation with MPO activity, IL-16, MIF, and IL-1Ra, suggesting that VAP2-APOA1 formation in HDL triggers microvascular injury. VasSF may reverse the injury by removing APOA1-VAP2 heterodimers from peripheral blood vessels.

Noninvasive biomarkers for lupus nephritis

Lupus nephritis (LN) is one of the most severe clinical manifestations of systemic lupus erythematosus (SLE). Notably, the clinical manifestations of LN are not always consistent with the histopathological findings. Therefore, the diagnosis and activity monitoring of this disease are challenging and largely depend on invasive renal biopsy. Renal biopsy has side effects and is associated with the risk of bleeding and infection. There is a growing interest in the development of novel noninvasive biomarkers for LN. In this review, we summarize most of the LN biomarkers discovered so far by correlating current knowledge with future perspectives. These biomarkers fundamentally reflect the biological processes of kidney damage and repair during disease. Furthermore, this review highlights the role of urinary cell phenotype detection in the diagnosis, monitoring, and treatment of LN and summarizes the limitations and countermeasures of this test.

Interleukins in Urine and Blood as Markers of Infection and as Risk Factors for Systemic Conditions

Interleukins are a diverse group of cytokines that play a crucial role in controlling immune responses and have potential as biomarkers. This mini review evaluates 12 recent papers linking urinary interleukins to both urinary infection and systemic diseases. While measurement of serum interleukins can indicate systemic inflammation, urinary interleukins provide more specific insights into renal or urinary tract inflammation. Urinary interleukins such as IL-8, IL-18, and IL-1β show promise for diagnosing urinary tract infections and other conditions. However, their diagnostic utility is complicated by their wide distribution in the body and patient-related factors. Advances in analytical techniques have enhanced the sensitivity and speed of interleukin measurement, improving their clinical utility. PATIENT SUMMARY: This review highlights research showing that measurement of molecules associated with the immune system in urine samples can help in diagnosing and monitoring disease affecting the urinary tract and kidneys. These urine tests can provide more specific information about infections than blood tests can.

Hyperalgesic Effect Evoked by il-16 and its Participation in Inflammatory Hypernociception in Mice

The systemic administration of interleukin-16 (IL-16, 3-30 ng/kg) induced thermal hyperalgesia in mice, that was prevented by the acute injection of an anti-CD4 antibody (1 µg/kg), the depletion of circulating white blood cells by cyclophosphamide or the specific reduction of circulating CD4+ cells provoked by a high dose of an anti-CD4 antibody (30 µg/mouse, 24 h before). IL-16-induced hyperalgesia was locally inhibited after intraplantar (i.pl.) administration of the non-selective cyclooxygenase (COX) inhibitor diclofenac, the COX-1 inhibitor SC-560, the COX-2 inhibitor celecoxib, the TRPV1 antagonist capsazepine or the TRPA1 antagonist HC030031, thus demonstrating that prostaglandins and TRP channels are involved in this effect. The i.pl. administration of low doses of IL-16 (0.1-1 ng) evoked local hyperalgesia suggesting the possibility that IL-16 could participate in hypernociception associated to local tissue injury. Accordingly, IL-16 concentration measured by ELISA was increased in paws acutely inflamed with carrageenan or chronically inflamed with complete Freund´s adjuvant (CFA). This augmentation was reduced after white cell depletion with cyclophosphamide or neutrophil depletion with an anti-Ly6G antibody. Immunofluorescence and flow cytometry experiments showed that the increased concentration of IL-16 levels found in acutely inflamed paws is mainly related to the infiltration of IL-16+ neutrophils, although a reduced number of IL-16+ lymphocytes was also detected in paws inflamed with CFA. Supporting the functional role of IL-16 in inflammatory hypernociception, the administration of an anti-IL-16 antibody dose-dependently reduced carrageenan- and CFA-induced thermal hyperalgesia and mechanical allodynia. The interest of IL-16 as a target to counteract inflammatory pain is suggested.

Investigating the value of urinary biomarkers in relation to lupus nephritis histopathology: present insights and future prospects

Lupus nephritis (LN), a leading cause of death in Systemic Lupus Erythematosus (SLE) patients, presents significant diagnostic and prognostic challenges. Although renal pathology offers critical insights regarding the diagnosis, classification, and therapy for LN, its clinical utility is constrained by the invasive nature and limited reproducibility of renal biopsies. Moreover, the continuous monitoring of renal pathological changes through repeated biopsies is impractical. Consequently, there is a growing interest in exploring urine as a non-invasive, easily accessible, and dynamic "liquid biopsy" alternative to guide clinical management. This paper examines novel urinary biomarkers from a renal pathology perspective, encompassing cellular components, cytokines, adhesion molecules, auto-antibodies, soluble leukocyte markers, light chain fragments, proteins, small-molecule peptides, metabolomics, urinary exosomes, and ribonucleic acids. We also discuss the application of combined models comprising multiple biomarkers in assessing lupus activity. These innovative biomarkers and models offer insights into LN disease activity, acute and chronic renal indices, fibrosis, thrombotic microangiopathy, podocyte injury, and other pathological changes, potentially improving the diagnosis, management, and prognosis of LN. These urinary biomarkers or combined models may serve as viable alternatives to traditional renal pathology, potentially revolutionizing the method for future LN diagnosis and observation.

Urine proteomic signatures of histological class, activity, chronicity, and treatment response in lupus nephritis

Lupus nephritis (LN) is a pathologically heterogenous autoimmune disease linked to end-stage kidney disease and mortality. Better therapeutic strategies are needed as only 30%-40% of patients completely respond to treatment. Noninvasive biomarkers of intrarenal inflammation may guide more precise approaches. Because urine collects the byproducts of kidney inflammation, we studied the urine proteomic profiles of 225 patients with LN (573 samples) in the longitudinal Accelerating Medicines Partnership in RA/SLE cohort. Urinary biomarkers of monocyte/neutrophil degranulation (i.e., PR3, S100A8, azurocidin, catalase, cathepsins, MMP8), macrophage activation (i.e., CD163, CD206, galectin-1), wound healing/matrix degradation (i.e., nidogen-1, decorin), and IL-16 characterized the aggressive proliferative LN classes and significantly correlated with histological activity. A decline of these biomarkers after 3 months of treatment predicted the 1-year response more robustly than proteinuria, the standard of care (AUC: CD206 0.91, EGFR 0.9, CD163 0.89, proteinuria 0.8). Candidate biomarkers were validated and provide potentially treatable targets. We propose these biomarkers of intrarenal immunological activity as noninvasive tools to diagnose LN and guide treatment and as surrogate endpoints for clinical trials. These findings provide insights into the processes involved in LN activity. This data set is a public resource to generate and test hypotheses and validate biomarkers.

Single cell spatial transcriptomic profiling of childhood-onset lupus nephritis reveals complex interactions between kidney stroma and infiltrating immune cells

Children with systemic lupus erythematosus (SLE) are at increased risk of developing kidney disease, termed childhood-onset lupus nephritis (cLN). Single cell transcriptomics of dissociated kidney tissue has advanced our understanding of LN pathogenesis, but loss of spatial resolution prevents interrogation of in situ cellular interactions. Using a technical advance in spatial transcriptomics, we generated a spatially resolved, single cell resolution atlas of kidney tissue (>400,000 cells) from eight cLN patients and two controls. Annotated cells were assigned to 35 reference cell types, including major kidney subsets and infiltrating immune cells. Analysis of spatial distribution demonstrated that individual immune lineages localize to specific regions in cLN kidneys, including myeloid cells trafficking to inflamed glomeruli and B cells clustering within tubulointerstitial immune hotspots. Notably, gene expression varied as a function of tissue location, demonstrating how incorporation of spatial data can provide new insights into the immunopathogenesis of SLE. Alterations in immune phenotypes were accompanied by parallel changes in gene expression by resident kidney stromal cells. However, there was little correlation between histologic scoring of cLN disease activity and glomerular cell transcriptional signatures at the level of individual glomeruli. Finally, we identified modules of spatially-correlated gene expression with predicted roles in induction of inflammation and the development of tubulointerstitial fibrosis. In summary, single cell spatial transcriptomics allows unprecedented insights into the molecular heterogeneity of cLN, paving the way towards more targeted and personalized treatment approaches.

Clinical diagnostic value of IL-14, 1L-16 and SAA in periodontitis

OBJECTIVES

Periodontitis is a chronic infectious disease, which leads to inflammatory destruction of periodontal supporting tissues. Interleukin 14 (IL-14), Interleukin 16 (IL-16) and serum amyloid A (SAA) have been demonstrated to be abnormally expressed in inflammatory diseases. Therefore, this study was performed to analyzed the expression and potential clinical values of IL-14, 1L-16 and SAA in periodontitis.

MATERIALS AND METHODS

A total of 100 periodontitis patients and 100 healthy volunteers were recruited and the saliva and serum samples were collected. Then the C-reactive protein (CRP), procalcitonin (PCT), IL-14, 1L-16 and SAA levels in the saliva and serum of periodontitis patients were measured by Elisa kits. Besides, the significance of CRP, PCT, IL-14, 1L-16 and SAA in periodontitis patients were analyzed by receiver operating characteristic (ROC) analysis.

RESULTS

The results showed that CRP, PCT, IL-14, 1L-16 and SAA levels were significantly increased in the the saliva and serum of the periodontitis patients. Additionally, the area under the curve (AUC) of saliva CRP, PCT, IL-14, 1L-16 and SAA for the diagnosis of periodontitis were 0.9035, 0.9435, 0.9508, 0.9500 and 0.9467, respectively. The AUC of serum CRP, PCT, IL-14, 1L-16 and SAA for the diagnosis of periodontitis were 0.9035, 0.9435, 0.9508, 0.9500 and 0.9467, respectively. What's more, the diagnostic value of IL-14, 1L-16 and SAA were enhanced when combining with CRP and PCT.

CONCLUSION AND CLINICAL RELEVANCE

This study demonstrated that IL-14, IL-16 and SAA expressions were upregulated in periodontitis patients and exhibited a significant significance for periodontitis diagnosis.

Advanced methods and novel biomarkers in autoimmune diseases ‑ a review of the recent years progress in systemic lupus erythematosus

There are several autoimmune and rheumatic diseases affecting different organs of the human body. Multiple sclerosis (MS) mainly affects brain, rheumatoid arthritis (RA) mainly affects joints, Type 1 diabetes (T1D) mainly affects pancreas, Sjogren's syndrome (SS) mainly affects salivary glands, while systemic lupus erythematosus (SLE) affects almost every organ of the body. Autoimmune diseases are characterized by production of autoantibodies, activation of immune cells, increased expression of pro-inflammatory cytokines, and activation of type I interferons. Despite improvements in treatments and diagnostic tools, the time it takes for the patients to be diagnosed is too long, and the main treatment for these diseases is still non-specific anti-inflammatory drugs. Thus, there is an urgent need for better biomarkers, as well as tailored, personalized treatment. This review focus on SLE and the organs affected in this disease. We have used the results from various rheumatic and autoimmune diseases and the organs involved with an aim to identify advanced methods and possible biomarkers to be utilized in the diagnosis of SLE, disease monitoring, and response to treatment.

Pathogenic cellular and molecular mediators in lupus nephritis

Kidney involvement in patients with systemic lupus erythematosus - lupus nephritis (LN) - is one of the most important and common clinical manifestations of this disease and occurs in 40-60% of patients. Current treatment regimens achieve a complete kidney response in only a minority of affected individuals, and 10-15% of patients with LN develop kidney failure, with its attendant morbidity and considerable prognostic implications. Moreover, the medications most often used to treat LN - corticosteroids in combination with immunosuppressive or cytotoxic drugs - are associated with substantial side effects. Advances in proteomics, flow cytometry and RNA sequencing have led to important new insights into immune cells, molecules and mechanistic pathways that are instrumental in the pathogenesis of LN. These insights, together with a renewed focus on the study of human LN kidney tissue, suggest new therapeutic targets that are already being tested in lupus animal models and early-phase clinical trials and, as such, are hoped to eventually lead to meaningful improvements in the care of patients with systemic lupus erythematosus-associated kidney disease.