Inhibition of ErbB kinase signalling promotes resolution of neutrophilic inflammation.

Neutrophilic inflammation with prolonged neutrophil survival is common to many inflammatory conditions, including chronic obstructive pulmonary disease (COPD). There are few specific therapies that reverse neutrophilic inflammation, but uncovering mechanisms regulating neutrophil survival is likely to identify novel therapeutic targets. Screening of 367 kinase inhibitors in human neutrophils and a zebrafish tail fin injury model identified ErbBs as common targets of compounds that accelerated inflammation resolution.

Effect of belimumab on proteinuria and anti-phospholipase A2 receptor autoantibody in primary membranous nephropathy.

Background: Immunosuppressant drugs reduce proteinuria and anti-phospholipase A2 receptor autoantibodies (PLA2R-Ab) in primary membranous nephropathy (PMN) with varying success and associated toxicities. This study aimed to evaluate the effect of belimumab on proteinuria and PLA2R-Ab in participants with PMN.

Methods: In this prospective, open-label, experimental medicine study, 14 participants with PMN and persistent nephrotic-range proteinuria received up to 2 years belimumab monotherapy (10 mg/kg, every 4 weeks).

Target engagement and cellular fate of otelixizumab: a repeat dose escalation study of an anti-CD3ε mAb in new-onset type 1 diabetes mellitus patients.

Aims: This paper describes the pharmacological findings from a study where otelixizumab, an anti-CD3ɛ mAb, was dosed in new onset Type 1 diabetes mellitus (NOT1DM) patients. This is the first time that the full dose-response of an anti-CD3ɛ mAb has been investigated in the clinic. The data have been validated using a previously developed pharmacokinetic/pharmacodynamic (PK/PD) model of otelixizumab to simulate the interplay between drug administration, CD3ɛ target engagement and downmodulation.

Belimumab in kidney transplantation: an experimental medicine, randomised, placebo-controlled phase 2 trial.

Background: B cells produce alloantibodies and activate alloreactive T cells, negatively affecting kidney transplant survival. By contrast, regulatory B cells are associated with transplant tolerance. Immunotherapies are needed that inhibit B-cell effector function, including antibody secretion, while sparing regulators and minimising infection risk.

Expression and regulation of drug transporters in vertebrate neutrophils.

There remains a need to identify novel pro-resolution drugs for treatment of inflammatory disease. To date, there are no neutrophil-specific anti-inflammatory treatments in clinical use, perhaps due to our lack of understanding of how drugs access this complex cell type. Here we present the first comprehensive description and expression of both major classes of drug transporters, SLC and ABC, in resting human blood neutrophils.

A distinct plasmablast and naïve B-cell phenotype in primary immune thrombocytopenia.

Primary immune thrombocytopenia is an autoimmune disorder in which platelet destruction is a consequence of both B- and T-cell dysregulation. Flow cytometry was used to further characterize the B- and T-cell compartments in a cross-sectional cohort of 26 immune thrombocytopenia patients including antiplatelet antibody positive (n=14) and negative (n=12) patients exposed to a range of therapies, and a cohort of matched healthy volunteers. Markers for B-cell activating factor and its receptors, relevant B-cell activation markers (CD95 and CD21) and markers for CD4(+) T-cell subsets, including circulating T-follicular helper-like cells, were included.

Skewed Fc glycosylation profiles of anti-proteinase 3 immunoglobulin G1 autoantibodies from granulomatosis with polyangiitis patients show low levels of bisection, galactosylation, and sialylation.

Granulomatosis with polyangiitis (GPA) is associated with circulating immunoglobulin (Ig) G anti-proteinase 3 specific (anti-PR3) anti-neutrophil cytoplasm antibodies (ANCA), which activate cytokine primed neutrophils via Fcgamma receptors. ANCA are class switched IgG antibodies implying T cell help in their production. Glycosylation of IgG Fc, under the control of T cell cytokines, determines the interaction between IgG and its receptors.

Rituximab versus cyclophosphamide in ANCA-associated renal vasculitis: 2-year results of a randomised trial.

Objectives: The RITUXVAS trial reported similar remission induction rates and safety between rituximab and cyclophosphamide based regimens for antineutrophil cytoplasm antibody (ANCA)-associated vasculitis at 12 months; however, immunosuppression maintenance requirements and longer-term outcomes after rituximab in ANCA-associated renal vasculitis are unknown.

Methods: Forty-four patients with newly diagnosed ANCA-associated vasculitis and renal involvement were randomised, 3:1, to glucocorticoids plus either rituximab (375 mg/m(2)/week×4) with two intravenous cyclophosphamide pulses (n=33, rituximab group), or intravenous cyclophosphamide for 3-6 months followed by azathioprine (n=11, control group).

Results: The primary end point at 24 months was a composite of death, end-stage renal disease and relapse, which occurred in 14/33 in the rituximab group (42%) and 4/11 in the control group (36%) (p=1.

Podocytes regulate neutrophil recruitment by glomerular endothelial cells via IL-6-mediated crosstalk.

Stromal cells actively modulate the inflammatory process, in part by influencing the ability of neighboring endothelial cells to support the recruitment of circulating leukocytes. We hypothesized that podocytes influence the ability of glomerular endothelial cells (GEnCs) to recruit neutrophils during inflammation. To address this, human podocytes and human GEnCs were cultured on opposite sides of porous inserts and then treated with or without increasing concentrations of TNF-α prior to addition of neutrophils.

Serum and glucocorticoid-regulated kinase 1 regulates neutrophil clearance during inflammation resolution.

The inflammatory response is integral to maintaining health by functioning to resist microbial infection and repair tissue damage. Large numbers of neutrophils are recruited to inflammatory sites to neutralize invading bacteria through phagocytosis and the release of proteases and reactive oxygen species into the extracellular environment. Removal of the original inflammatory stimulus must be accompanied by resolution of the inflammatory response, including neutrophil clearance, to prevent inadvertent tissue damage.

Modulating the Adhesion of Haematopoietic Stem Cells with Chemokines to Enhance Their Recruitment to the Ischaemically Injured Murine Kidney.

Introduction: Renal disease affects over 500 million people worldwide and is set to increase as treatment options are predominately supportive. Evidence suggests that exogenous haematopoietic stem cells (HSCs) can be of benefit but due to the rarity and poor homing of these cells, benefits are either minor or transitory. Mechanisms governing HSC recruitment to injured renal microcirculation are poorly understood; therefore this study determined (i) the adhesion molecules responsible for HSC recruitment to the injured kidney, (ii) if cytokine HSC pre-treatment can enhance their homing and (iii) the molecular mechanisms accountable for any enhancement.

PR3 and elastase alter PAR1 signaling and trigger vWF release via a calcium-independent mechanism from glomerular endothelial cells.

Neutrophil proteases, proteinase-3 (PR3) and elastase play key roles in glomerular endothelial cell (GEC) injury during glomerulonephritis. Endothelial protease-activated receptors (PARs) are potential serine protease targets in glomerulonephritis. We investigated whether PAR1/2 are required for alterations in GEC phenotype that are mediated by PR3 or elastase during active glomerulonephritis.

Genetically distinct subsets within ANCA-associated vasculitis.

Background: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a severe condition encompassing two major syndromes: granulomatosis with polyangiitis (formerly known as Wegener's granulomatosis) and microscopic polyangiitis. Its cause is unknown, and there is debate about whether it is a single disease entity and what role ANCA plays in its pathogenesis. We investigated its genetic basis.

Neutrophil serine proteases mediate inflammatory cell recruitment by glomerular endothelium and progression towards dysfunction.

Background: Neutrophil recruitment into glomerular tissues and reduced capillary wall integrity has been implicated in the development of vasculitic glomerulonephritis (VGN). This study investigated the stages and mechanisms through which neutrophil serine proteases (SPs), proteinase 3 (PR3) or elastase contribute to endothelial dysfunction.

Methods: Protease-induced damage to endothelium and adhesion molecule upregulation was measured by viability assays and ELISA.

Biology of the renal pericyte.

Pericytes are cells of mesenchymal origin that are intimately involved in the development and stabilization of vascular networks. Novel studies of their role in inflammation have identified that pericytes are not only major contributors to the activated matrix depositing myofibroblast populations seen in progressive renal fibrosis but perhaps even more importantly, the detachment of renal pericytes from the vasculature contributes to the microvasculature rarefaction and subsequent hypoxia associated with chronic kidney disease. In this review, our current understanding of the functioning of renal pericytes will be considered and set in the context of the wider literature that is currently available on this neglected population of cells.

Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3) antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener's granulomatosis). Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system.

Pulse versus daily oral cyclophosphamide for induction of remission in ANCA-associated vasculitis: long-term follow-up.

Introduction: The previously reported randomised controlled trial of a consensus regimen of pulse cyclophosphamide suggested that it was as effective as a daily oral (DO) cyclophosphamide for remission induction of antineutrophil cytoplasm autoantibodies-associated systemic vasculitis when both were combined with the same glucocorticoid protocol (CYCLOPS study (Randomised trial of daily oral versus pulse Cyclophosphamide as therapy for ANCA-associated Systemic Vasculitis published de groot K, harper L et al Ann Int Med 2009)). The study had limited power to detect a difference in relapse. This study describes the long-term outcomes of patients in the CYCLOPS study.

Anti-neutrophil cytoplasmic antibodies stimulate release of neutrophil microparticles.

The mechanisms by which anti-neutrophil cytoplasmic antibodies (ANCAs) may contribute to the pathogenesis of ANCA-associated vasculitis are not well understood. In this study, both polyclonal ANCAs isolated from patients and chimeric proteinase 3-ANCA induced the release of neutrophil microparticles from primed neutrophils. These microparticles expressed a variety of markers, including the ANCA autoantigens proteinase 3 and myeloperoxidase.

Immune profile and Epstein-Barr virus infection in acute interstitial nephritis: an immunohistochemical study in 78 patients.

Background: Acute interstitial nephritis (AIN) is a common cause of acute kidney injury and is characterised by a dense interstitial cellular infiltrate, which has not been well defined. Previous studies have demonstrated a correlation between Epstein-Barr virus (EBV) infection and AIN. The purpose of our study was to define the nature of the interstitial immune infiltrate and to investigate the possibility of renal infection with EBV.

A dual role for diacylglycerol kinase generated phosphatidic acid in autoantibody-induced neutrophil exocytosis.

Dysregulated release of neutrophil azurophilic granules causes increased tissue damage and amplified inflammation during autoimmune disease. Antineutrophil cytoplasmic antibodies (ANCAs) are implicated in the pathogenesis of small vessel vasculitis and promote adhesion and exocytosis in neutrophils. ANCAs activate specific signal transduction pathways in neutrophils that have the potential to be modulated therapeutically to prevent neutrophil activation by ANCAs.

Recommendations for the use of rituximab in anti-neutrophil cytoplasm antibody-associated vasculitis.

Objectives: To perform a literature review and develop recommendations for the use of rituximab in ANCA-associated vasculitis.

Methods: A committee of experts (five rheumatologists, five nephrologists and one paediatrician) conducted a modified Delphi exercise to identify five topics for a systematic literature search. The evidence was then reviewed, categorized according to international criteria and assimilated to form five recommendations statements and a research agenda.

CD248+ stromal cells are associated with progressive chronic kidney disease.

Stromal fibroblasts are the primary cells of the kidney that produce fibrotic matrix. CD248 is a stromal marker expressed on fibroblasts and pericytes within the human kidney. Here, we tested whether CD248 expression in the kidney colocalizes with fibrosis and if it is associated with known determinants of chronic kidney disease (CKD).