The switch from proteasome to immunoproteasome is increased in circulating cells of patients with fast progressive immunoglobulin A nephropathy and associated with defective CD46 expression.

The proteasome to immunoproteasome (iPS) switch consists of β1, β2 and β5 subunit replacement by low molecular weight protein 2 (LMP2), LMP7 and multicatalytic endopeptidase-like complex-1 (MECL1) subunits, resulting in a more efficient peptide preparation for major histocompatibility complex 1 (MHC-I) presentation. It is activated by toll-like receptor (TLR) agonists and interferons and may also be influenced by genetic variation. In a previous study we found an iPS upregulation in peripheral cells of patients with immunoglobulin A nephropathy (IgAN).

Defective gene expression of the membrane complement inhibitor CD46 in patients with progressive immunoglobulin A nephropathy.

Background: Complement is thought to play a role in immunoglobulin A nephropathy (IgAN), though the activating mechanisms are unknown. This study focused on the gene expression of CD46 and CD55, two key molecules for regulating C3 convertase activity of lectin and alternative complement pathways at a cellular level.

Methods: The transcriptional expression in peripheral white blood cells (WBCs) of CD46 and CD55 was investigated in 157 patients enrolled by the Validation of the Oxford Classification of IgAN group, looking for correlations with clinical and pathology features and estimated glomerular filtration rate (eGFR) modifications from renal biopsy to sampling.

HERV-K and W expression in peripheral mononuclear cells of children with Henoch-Schönlein purpura and relation with TLR activation.

Background: HERVs expression seems impaired in several diseases, ranging from autoimmune to neoplastic disorders. However, various stimuli may re-activate HERVs transcription. Henoch-Schönlein purpura is the most common cause of vasculitis in children.

A novel TaqMAMA assay for allelic discrimination of immunoproteasome subunit PSMB8 in pediatric patients.

Background: A more recent improvement in MAMA was made when the allele selectivity of MAMA primers was combined with the 5' fluorogenic exonuclease (TaqMan) assay. This strategy referred to as TaqMAMA.

Methods: A SNP rs9357155 at the PSMB8 locus (GenBank access number NM_148919.

Toll-like receptors are essential for the control of endogenous retrovirus expression in Idiopathic Nephrotic Syndrome.

Background: Idiopathic nephrotic syndrome (INS) in children is a continuum of clinical disorders characterized by severe proteinuria, dyslipidemia, hypoalbuminemia, and hypercoagulability. It has been hypothesized that toll-like receptors (TLRs) in peripheral blood mononuclear cell might be involved in INS disease. Infections appear to be involved in the onset of INS.

Standard and immunoproteasome expression in pediatric tonsillectomy patients.

Background: Pro-inflammatory cytokines including TNF-α and IFN-γ, play an important role during the recurrent tonsillitis illness and proteasome and immunoproteasome stimulation.

Methods: mRNA expression analysis of proteasome and immunoproteasome subunits was performed by PBMC whole blood isolation from children tonsillectomy patients. Total RNA was extracted from PBMC and retro-transcribed in cDNA.

Development of a degenerated TaqMan real-time Q-PCR for detection of bacteria-free DNA in dialysis fluid.

Bacterial-derived DNA fragments (BDNAs) have been shown to be present in a dialysis fluid, to pass through dialyzer membranes, and to induce interleukin 6 (IL-6) in mononuclear cells. DNA fragments are thought to be derived from microorganisms inhabiting hemodialysis water and fluid. The primary aim of the present study was to develop two degenerated TaqMan real-time quantitative-PCR (Q-PCR) for detection of a broad range of bacterial DNA that specifically detect 16S ribosomal DNA (rDNA) (862 and 241 bp) and evaluate the efficiency of the Bellco Selecta resin to capture the BDNAs in the dialysis fluid.

Evaluation of IFN-γ polymorphism+874 T/A in patients with recurrent tonsillitis by PCR real time mismatch amplification mutation assay (MAMA real time PCR).

Interferon gamma (IFN-γ) is an important cytokine that plays a crucial role in the balance between normal and pathological immune response. Defect of IFN-γ can give a predisposition to infectious disease, autoimmune pathologies and tumours. Different polymorphisms in this gene have been described, in particular the single nucleotide polymorphism (SNP)+874∗T/A that may affect IFN-γ gene expression.

Evaluation of UL99 transcript as a target for antiviral treatment efficacy.

Human cytomegalovirus (HCMV) is a virus belonging to the Beta Herpes virus family. Its genome contains many different genes clustered in immediate early, early and late genes. This last cluster includes UL99, a late gene that encodes for a tegument protein called pp28.

Can tonsillectomy modify the innate and adaptive immunity pathways involved in IgA nephropathy?

The benefits of tonsillectomy in IgA nephropathy (IgAN) are still debated. Tonsillectomy may remove pathogen sources and reduce the mucosal associated lymphoid tissue (MALT), limiting degalactosylated IgA1 (deGal-IgA1) production, which is considered to be the initiating pathogenetic event leading to IgA glomerular deposition. In the European network VALIGA, 62/1147 IgAN patients underwent tonsillectomy (TxIgAN).

Toll-like receptors, immunoproteasome and regulatory T cells in children with Henoch-Schönlein purpura and primary IgA nephropathy.

Background: Henoch-Schönlein purpura (HSP) nephritis and primary IgA nephropathy (pIgAN) present with glomerular IgA deposits, but differ with regard to clinical features. The suspected involvement of different immune system pathways is largely unknown.

Methods: This study was aimed at investigating some of the immunological features including Toll-like receptors (TLR), proteasome (PS)/immunoproteasome (iPS) switch, and the regulatory T cell system (Treg/Th17 cells) in 63 children with HSP with/without renal involvement and in 25 with pIgAN.

Saquinavir in steroid-dependent and -resistant nephrotic syndrome: a pilot study.

Background: Some difficult cases of idiopathic nephrotic syndrome (NS) have been treated with a HIV protease inhibitor provided with proteasome-inhibiting activity. The objective of this study was to limit nuclear factor κB (NF-κB) activation which is up-regulated in these patients, aiming at decreasing proteinuria and prednisone need.

Methods: Ten cases with long-lasting (up to 15 years) history of NS with steroid dependence (six cases, of which three with secondary steroid resistance) or resistance to steroids (four cases) unsuccessfully treated with multiple immunosuppressive drugs, accepted a treatment with the protease inhibitor saquinavir.

Oxidative stress and galactose-deficient IgA1 as markers of progression in IgA nephropathy.

Background And Objectives: We assessed the activation of the oxidative stress pathway in patients with IgA nephropathy (IgAN), while evaluating the classic marker of the disease (galactose-deficient serum IgA1).

Design, Setting, Participants, & Measurements: Sera from 292 patients and 69 healthy controls from Italy and the United States were assayed for advanced oxidation protein products (AOPPs), free sulfhydryl groups on albumin (SH-Alb), and IgA1 with galactose-deficient hinge-region O-glycans (Gd-IgA1). Gd-IgA1 was detected by binding to Helix aspersa agglutinin (HAA) and expressed as total Gd-IgA1 or as degree of galactose deficiency relative to a standard Gd-IgA1 myeloma protein (%HAA).

Aberrantly glycosylated IgA1 induces mesangial cells to produce platelet-activating factor that mediates nephrin loss in cultured podocytes.

The reaction of mesangial cells with aberrantly glycosylated IgA1 has been implicated in the etiology of IgA nephropathy (IgAN). Tumor necrosis factor, which is assumed to mediate the interaction between mesangial cells and podocytes, also induces the expression of platelet-activating factor (PAF). In this study, we determined whether PAF affects the expression of nephrin (an adhesion molecule critical to glomerular permselectivity) and cytoskeletal F-actin organization in podocytes.

Effect of glucose degradation products, glucose-containing dialysate and icodextrin on AQP1 and eNOS expression in cultured endothelial cells.

Background: Aquaporin-1 (AQP1) and endothelial NO synthase (eNOS) expression on the endothelium of peritoneal vessels modulates ultrafiltration during peritoneal dialysis (PD) by different mechanisms. Protracted eNOS activation may, in the long term, be deleterious for peritoneal functioning. We aimed at examining the effect of peritoneal dialysis solutions (PDSs) and glucose degradation products (GDPs) on the expression of AQP1 and eNOS in cultured endothelial cells.