Association Between High NK-Cell Count and Remission of Primary Membranous Nephropathy: A Retrospective Chart Review and Pilot Study.

Purpose: Primary membranous nephropathy (PMN) is the most frequent cause of nephrotic syndrome in adults. Rituximab monotherapy has emerged as a front-line treatment for patients with PMN, but potential markers for predicting the response to rituximab are unknown.

Methods: In this single-arm retrospective pilot study, 48 patients with PMN without previous immunosuppressive therapy were enrolled.

DNA binding protein YB-1 is a part of the neutrophil extracellular trap mediation of kidney damage and cross-organ effects.

Open-heart surgery is associated with high morbidity, with acute kidney injury (AKI) being one of the most commonly observed postoperative complications. Following open-heart surgery, in an observational study we found significantly higher numbers of blood neutrophils in a group of 13 patients with AKI compared to 25 patients without AKI (AKI: 12.9±5.

YB-1 Interferes with TNFα-TNFR Binding and Modulates Progranulin-Mediated Inhibition of TNFα Signaling.

Inflammation and an influx of macrophages are common elements in many diseases. Among pro-inflammatory cytokines, tumor necrosis factor α (TNFα) plays a central role by amplifying the cytokine network. Progranulin (PGRN) is a growth factor that binds to TNF receptors and interferes with TNFα-mediated signaling.

Reevaluation of Lung Injury in TNF-Induced Shock: The Role of the Acid Sphingomyelinase.

Tumor necrosis factor (TNF) is a well-known mediator of sepsis. In many cases, sepsis results in multiple organ injury including the lung with acute respiratory distress syndrome (ARDS). More than 20-year-old studies have suggested that TNF may be directly responsible for organ injury during sepsis.

The nucleic acid binding protein YB-1-controlled expression of CXCL-1 modulates kidney damage in liver fibrosis.

Acute kidney injury is a common complication of advanced liver disease and increased mortality of these patients. Here, we analyzed the role of Y-box protein-1 (YB-1), a nucleic acid binding protein, in the bile duct ligation model of liver fibrosis and monitored liver and subsequent kidney damage. Following bile duct ligation, both serum levels of liver enzymes and expression of hepatic extracellular matrix components such as type I collagen were significantly reduced in mice with half-maximal YB-1 expression (Yb1) as compared to their wild-type littermates.

The YB-1:Notch-3 axis modulates immune cell responses and organ damage in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease and lupus nephritis is a major risk factor for morbidity and mortality. Notch-3 signaling induced by membrane-bound or soluble ligands such as YB-1 constitutes an evolutionarily conserved pathway that determines major decisions in cell fate. Mass spectrometry of extracellular YB-1 in sera from patients with SLE and lupus-prone mice revealed specific post-translational guanidinylation of two lysine residues within the highly conserved cold-shock domain of YB-1 (YB-1-G).

High-fat diet-induced obesity causes an inflammatory microenvironment in the kidneys of aging Long-Evans rats.

Background: Obesity is a risk factor for chronic kidney disease (CKD). While the exact mechanisms remain unclear, inflammation may be a consequence of obesity that directly impacts the kidneys. The aim of this study was to examine the inflammatory status of the kidneys and potential ongoing renal damage, i.

Identification of platelet-derived growth factor C as a mediator of both renal fibrosis and hypertension.

Platelet-derived growth factors (PDGF) have been implicated in kidney disease progression. We previously found that PDGF-C is upregulated at sites of renal fibrosis and that antagonism of PDGF-C reduces fibrosis in the unilateral ureteral obstruction model. We studied the role of PDGF-C in collagen 4A3 ("Alport") mice, a model of progressive renal fibrosis with greater relevance to human kidney disease.

YB-1 increases glomerular, but decreases interstitial fibrosis in CNI-induced nephropathy.

Calcineurin inhibitors (CNIs) are a cornerstone of the current treatment in solid organ transplantation and autoimmune disease. However, CNIs also bear deleterious effects as they cause glomerular and tubulointerstitial fibrosis in the kidney. We recently identified Y-box protein-1 (YB-1) as a novel downstream effector of CNI-signaling in the cytoplasm of glomerular cells.

Complement C5a receptors C5L2 and C5aR in renal fibrosis.

Complement factor C5a has two known receptors, C5aR, which mediates proinflammatory effects, and C5L2, a potential C5a decoy receptor. We previously identified C5a/C5aR signaling as a potent profibrotic pathway in the kidney. Here we tested for the first time the role of C5L2 in renal fibrosis.

YB-1 orchestrates onset and resolution of renal inflammation via IL10 gene regulation.

The Y-box-binding protein (YB)-1 plays a non-redundant role in both systemic and local inflammatory response. We analysed YB-1-mediated expression of the immune regulatory cytokine IL-10 in both LPS and sterile inflammation induced by unilateral renal ischaemia-reperfusion (I/R) and found an important role of YB-1 not only in the onset but also in the resolution of inflammation in kidneys. Within a decisive cis-regulatory region of the IL10 gene locus, the fourth intron, we identified and characterized an operative YB-1 binding site via gel shift experiments and reporter assays in immune and different renal cells.

Therapeutic nuclear shuttling of YB-1 reduces renal damage and fibrosis.

Virtually all chronic kidney diseases progress towards tubulointerstitial fibrosis. In vitro, Y-box protein-1 (YB-1) acts as a central regulator of gene transcription and translation of several fibrosis-related genes. However, it remains to be determined whether its pro- or antifibrotic propensities prevail in disease.

Cold shock protein YB-1 is involved in hypoxia-dependent gene transcription.

Hypoxia-dependent gene regulation is largely orchestrated by hypoxia-inducible factors (HIFs), which associate with defined nucleotide sequences of hypoxia-responsive elements (HREs). Comparison of the regulatory HRE within the 3' enhancer of the human erythropoietin (EPO) gene with known binding motifs for cold shock protein Y-box (YB) protein-1 yielded strong similarities within the Y-box element and 3' adjacent sequences. DNA binding assays confirmed YB-1 binding to both, single- and double-stranded HRE templates.

IL-6 Trans-Signaling Drives Murine Crescentic GN.

The role of IL-6 signaling in renal diseases remains controversial, with data describing both anti-inflammatory and proinflammatory effects. IL-6 can act via classic signaling, engaging its two membrane receptors gp130 and IL-6 receptor (IL-6R). Alternatively, IL-6 trans-signaling requires soluble IL-6R (sIL-6R) to act on IL-6R-negative cells that express gp130.

Calcineurin-mediated YB-1 dephosphorylation regulates CCL5 expression during monocyte differentiation.

Y-box (YB) protein-1 serves as a master regulator in gene transcription and mRNA translation. YB-1 itself is regulated at various levels, e.g.

Gp130-dependent signaling in the podocyte.

Renal inflammation, in particular glomerular, is often characterized by increased IL-6 levels. The in vivo relevance of IL-6 signaling in glomerular podocytes, which play central roles in most glomerular diseases, is unknown. Here, we show that in normal mice, podocytes express gp130, the common signal-transducing receptor subunit of the IL-6 family of cytokines.

High prevalence of Y-box protein-1/p18 fragment in plasma of patients with malignancies of different origin.

Background: Expression of the cold shock protein Y-box protein 1 (YB-1) is associated with deleterious outcome in various malignant diseases. Our group recently showed that the detection of an 18 kDa YB-1 fragment (YB-1/p18) in human plasma identifies patients with malignant diseases. We now tested the prevalence, clinical, and diagnostic value of YB-1/p18 detection in common tumors.

Cold shock Y-box protein-1 proteolysis autoregulates its transcriptional activities.

Background: The Y-box protein-1 (YB-1) fulfills pleiotropic functions relating to gene transcription, mRNA processing, and translation. It remains elusive how YB-1 shuttling into the nuclear and cytoplasmic compartments is regulated and whether limited proteolysis by the 20S proteasome releases fragments with distinct function(s) and subcellular distribution(s).

Results: To address these questions, mapping of domains responsible for subcellular targeting was performed.

YB-1 is an early and central mediator of bacterial and sterile inflammation in vivo.

In vitro studies identified Y-box-binding protein (YB)-1 as a key regulator of inflammatory mediators. In this study, we observed increased levels of secreted YB-1 in sera from sepsis patients. This led us to investigate the in vivo role of YB-1 in murine models of acute peritonitis following LPS injection, in sterile renal inflammation following unilateral ureteral obstruction, and in experimental pyelonephritis.

Notch-3 receptor activation drives inflammation and fibrosis following tubulointerstitial kidney injury.

Kidney diseases impart a vast burden on affected individuals and the overall health care system. Progressive loss of renal parenchymal cells and functional decline following injury are often observed. Notch-1 and -2 receptors are crucially involved in nephron development and contribute to inflammatory kidney diseases.

Cold shock Y-box protein-1 participates in signaling circuits with auto-regulatory activities.

The cold shock protein Y-box (YB) binding-1 is an example of a highly regulated protein with pleiotropic functions. Besides activities as a transcription factor in the nucleus or regulator of translation in the cytoplasm, recent findings indicate extracellular effects and secretion via a non-classical secretion pathway. This review summarizes regulatory pathways in which YB-1 participates, all iterating auto-regulatory loops.

Role of cold shock Y-box protein-1 in inflammation, atherosclerosis and organ transplant rejection.

Chemokines (chemoattractant cytokines) are crucial regulators of immune cell extravasation from the bloodstream into inflamed tissue. Dysfunctional regulation and perpetuated chemokine gene expression are linked to progressive chronic inflammatory diseases and, in respect to transplanted organs, may trigger graft rejection. RANTES (regulated upon activation, normal T cell expressed and secreted (also known as CCL5)) is a model chemokine with relevance in numerous inflammatory diseases where the innate immune response predominates.

Induction of progressive glomerulonephritis by podocyte-specific overexpression of platelet-derived growth factor-D.

Platelet-derived growth factor-D (PDGF-D), normally expressed in podocytes, mediates mesangial cell proliferation in vivo. To study this further, we created transgenic mice with podocyte-specific overexpression of PDGF-D. Hemizygous mice were grossly indistinguishable from wild-type littermates through 11 months of age; however, hemizygous mice older than 4 weeks commonly exhibited increased cell proliferation within the glomerular tuft.

Y-box binding protein-1 mediates profibrotic effects of calcineurin inhibitors in the kidney.

The immunosuppressive calcineurin inhibitors (CNIs) cyclosporine A (CsA) and tacrolimus are widely used in transplant organ recipients, but in the kidney allograft, they may cause tubulointerstitial as well as mesangial fibrosis, with TGF-β believed to be a central inductor. In this study, we report that the cold-shock protein Y-box binding protein-1 (YB-1) is a TGF-β independent downstream effector in CsA- as well as in tacrolimus- but not in rapamycin-mediated activation of rat mesangial cells (rMCs). Intracellular content of YB-1 is several-fold increased in MCs following CNI treatment in vitro and in vivo in mice.

Extracellular YB-1 blockade in experimental nephritis upregulates Notch-3 receptor expression and signaling.

Background: Notch receptors are involved in kidney development and pathogenesis of inflammatory glomerular diseases. Given the secretion of Y-box (YB) protein-1 following cytokine stimulation and subsequent extracellular association with membrane receptor Notch-3 in vitro, we elucidated functional effects of YB-1 targeting on the Notch-3 signaling pathway.

Methods: Rat mesangial cells were challenged with a monoclonal anti-YB-1 antibody (YB-1-mAb) and analyzed for YB-1 and Notch-3 expression.