Detection of Autoantibodies Against the Acetylcholine Receptor, Evaluation of Commercially Available Methodologies: Fixed Cell-Based Assay, Radioimmunoprecipitation Assay and Enzyme-Linked Immunosorbent Assay1.

Background/objective: Myasthenia Gravis (MG) is an autoimmune disorder characterized by pathogenic autoantibodies (AAbs) targeting nicotinic acetylcholine receptors (AChR), disrupting neuromuscular communication. RadioImmunoPrecipitation Assay (RIPA) is recommended to detect AChR AAbs, but its complexity and radioactive requirements limit widespread use. We compare non-RIPA anti-AChR immunoassays, including Cell-Based Assay (CBA) and two ELISA kits, against the gold standard RIPA.

The Role of Autoantibody Testing in Modern Personalized Medicine.

Personalized medicine (PM) aims individualized approach to prevention, diagnosis, and treatment. Precision Medicine applies the paradigm of PM by defining groups of individuals with akin characteristics. Often the two terms have been used interchangeably.

Antinuclear antibodies (ANA) as a criterion for classification and diagnosis of systemic autoimmune diseases.

The classification and diagnosis of systemic autoimmune diseases are frequently based on a collection of criteria composed of clinical, laboratory, imaging, and pathology elements that are strongly associated with the respective disease. Autoantibodies are a distinctive hallmark and have a prominent position in the classification criteria of many autoimmune diseases. The indirect immunofluorescence assay on HEp-2 cells (HEp-2 IFA), historically known as the antinuclear antibody test, is a method capable of detecting a wide spectrum of autoantibodies.

Infusion of anti-DFS70 antibodies prolonged survival of lupus-prone mice.

Background: Systemic-lupus-nephritis is a chronic autoimmune disease characterized by immune complex deposition and a flare of autoantibodies and leading to renal injury.

Objectives: To expose anti-Dense-Fine-Speckled-70 (DFS70)-antibodies to genetically-prone-lupus-mice.

Methods: NZBXW/F1 female mice were monitored for the onset of glomerulonephritis by proteinuria upon infusion of anti-DFS70 (40 μg/mouse), commercial-human-IgG (cIgG) or phosphate-buffered-saline (PBS) as controls.

Evolving liver inflammation in biochemically normal individuals with anti-mitochondria antibodies.

Background: Anti-mitochondria autoantibodies (AMA) occur in > 95% primary biliary cholangitis (PBC) patients. Biochemically normal AMA-positive (BN/AMA+) individuals, occasionally noticed by indirect immunofluorescence (IIF) on HEp-2 cells and confirmed in AMA-specific assays, may represent early stages of PBC. The Enhanced Liver Fibrosis (ELF) score is a surrogate marker for liver fibrosis.

Ribavirin induces widespread accumulation of IMP dehydrogenase into rods/rings structures in multiple major mouse organs.

Ribavirin (RBV) is a guanosine analogue triazole most commonly used in the treatment of chronic hepatitis C (HCV) infection. Although its mechanism of action is a matter of debate, several possibilities have been proposed, including depletion of guanine nucleotides through inhibition of inosine monophosphate dehydrogenase (IMPDH). IMPDH has been shown to assemble into micron-scale rod- and ring-shaped structures (rods/rings or RR), also called "IMPDH filaments," both in vitro and in vivo.

Absence of mycobacterial DNA in peripheral blood and artery specimens in patients with Takayasu arteritis.

The objective of this study was to demonstrate the presence of mycobacterial nucleic acid sequences in peripheral blood and arteries from patients with Takayasu arteritis (TA). Polymerase chain reaction was performed to detect mycobacterial DNA from three different nucleic acid sequences including the insertion sequence (IS) 6110, the 65-kDa heat shock protein gene (HSP65), and the 16S ribosomal RNA (rRNA) gene in peripheral blood from 32 TA patients and in arterial specimens from 10 TA patients. Twenty-eight HIV-negative patients with pulmonary tuberculosis prior to therapy were tested for IS6110 in peripheral blood as positive controls, and 24 blood donors were evaluated as healthy controls (HC).

High frequency of immunodeficiency-like states in systemic lupus erythematosus: a cross-sectional study in 300 consecutive patients.

Objective: To determine the frequency of immunodeficiency-like states in SLE and related clinical features.

Methods: Three hundred and fifteen SLE patients and 301 controls were evaluated for C4A and C4B gene copy number, immunoglobulin isotypes, IgG subclasses, total haemolytic complement (CH50), C2, C3 and neutrophil oxidative burst. C2 and C3 genes were sequenced in cases of low C2 or C3 levels.

Anti-rods/rings autoantibody generation in hepatitis C patients during interferon-α/ribavirin therapy.

Chronic inflammation associated with hepatitis C virus (HCV) infection can lead to disabling liver diseases with progression to liver cirrhosis and hepatocellular carcinoma. Despite the recent availability of more effective and less toxic therapeutic options, in most parts of the world the standard treatment consists of a weekly injection of pegylated interferon α (IFN-α) together with a daily dose of ribavirin. HCV patients frequently present circulating non-organ-specific autoantibodies demonstrating a variety of staining patterns in the indirect immunofluorescence assay for antinuclear antibodies (ANA).

Behçet's disease heterogeneity: cytokine production and oxidative burst of phagocytes are altered in patients with severe manifestations.

Objectives: To test the hypothesis that classical phagocytic functions are constitutively stimulated in patients with Behçet's disease (BD).

Methods: Four study groups were analysed: active BD (aBD; n=30), inactive BD (iBD; n=31); septic patients (SP; n=25); healthy controls (HC; n=30). Microbicide activity against Streptococcus pneumoniae, Streptococcus sanguinis and Candida albicans was determined by means of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction and absorbance read by ELISA.

High mobility group box 1 serum levels are increased in Behçet's disease, but not associated with disease activity or disease manifestations.

Objectives: High mobility group box 1 (HMGB1) is a nuclear protein that acts as an alarmin when released into the extracellular milieu. HMGB1 is a biomarker of active disease in several systemic autoimmune diseases. Behçet's disease (BD) is a systemic inflammatory disorder with a waxing/waning course.

Assembly of IMPDH2-based, CTPS-based, and mixed rod/ring structures is dependent on cell type and conditions of induction.

Inhibition of guanosine triphosphate (GTP) and cytidine triphosphate (CTP) biosynthetic pathways induces cells to assemble rod/ring (RR) structures, also named cytoophidia, which consist of the enzymes cytidine triphosphate synthase (CTPS) and inosine-5'-monophosphate dehydrogenase 2 (IMPDH2). We aim to explore the interaction of CTPS and IMPDH2 in the generation of RR structures. HeLa and COS-7 cells were cultured in normal conditions or in the presence of 6-diazo-5-oxo-L-norleucine (DON), ribavirin, or mycophenolic acid (MPA).

High mobility group box 1 levels in large vessel vasculitis are not associated with disease activity but are influenced by age and statins.

Introduction: Takayasu arteritis (TA) and giant cell arteritis (GCA) are large vessel vasculitides (LVV) that usually present as granulomatous inflammation in arterial walls. High mobility group box 1 (HMGB1) is a nuclear protein that acts as an alarmin when released by dying or activated cells. This study aims to evaluate whether serum HMGB1 can be used as a biomarker in LVV.

Microinjection of specific anti-IMPDH2 antibodies induces disassembly of cytoplasmic rods/rings that are primarily stationary and stable structures.

Background: Our laboratory previously reported interesting rods 3-10 μm long and rings 2-5 μm diameter (RR) in the cytoplasm of mammalian cells. Experimental evidence show that both inosine-5'-monophosphate dehydrogenase 2 (IMPDH2) and cytidine triphosphate synthetase (CTPS) are components of RR structures. Several cell types, including mouse embryonic stem cells, and cell lines, such as mouse 3 T3 and rat NRK, naturally present RR structures, while other cells can present RR when treated with compounds interfering with GTP/CTP biosynthetic pathways.

Temporal evolution of human autoantibody response to cytoplasmic rods and rings structure during anti-HCV therapy with ribavirin and interferon-α.

Autoantibodies to inosine monophosphate dehydrogenase-2 (IMPDH2), an enzyme involved in de novo biosynthesis of guanine nucleotides, are observed in a subset of hepatitis C virus (HCV) patients receiving interferon alpha (IFN-α) plus ribavirin. Anti-IMPDH2 antibodies display a peculiar cytoplasmic "rod/ring" (RR) pattern in IIF-HEp-2. We examined the dynamics of anti-RR autoimmune response with respect to immunoglobulin isotypes, titer, avidity, and protein targets in 80 sequential samples from 15 HCV patients (plus 12 randomly selected anti-RR-positive, totalizing 92 samples) collected over an 18-month period, including samples collected before, during, and after IFN-α + ribavirin treatment.

Humoral autoimmune response heterogeneity in the spectrum of primary biliary cirrhosis.

Objective: To compare autoantibody features in patients with primary biliary cirrhosis (PBC) and individuals presenting antimitochondria antibodies (AMAs) but no clinical or biochemical evidence of disease.

Methods: A total of 212 AMA-positive serum samples were classified into four groups: PBC (definite PBC, n = 93); PBC/autoimmune disease (AID; PBC plus other AID, n = 37); biochemically normal (BN) individuals (n = 61); and BN/AID (BN plus other AID, n = 21). Samples were tested by indirect immunofluorescence (IIF) on rat kidney (IIF-AMA) and ELISA [antibodies to pyruvate dehydrogenase E2-complex (PDC-E2), gp-210, Sp-100, and CENP-A/B].

Longitudinal study of a human drug-induced model of autoantibody to cytoplasmic rods/rings following HCV therapy with ribavirin and interferon-α.

Background: A novel pattern in the indirect immunofluorescence antinuclear antibody assay on HEp-2 cells (IIF-HEp-2) characterized by cytoplasmic rods and rings (RR) was reported in HCV patients, but stringent disease specificity studies and longitudinal analysis are lacking. We investigated the clinical significance of anti-RR in an HCV cohort with up to a 12-month treatment follow up.

Methodology/results: 597 patients (342 HCV, 55 HCV/HIV, 200 non-HCV) were screened and titered for anti-RR.

IL-2, IL-5, TNF-α and IFN-γ mRNA expression in epidermal keratinocytes of systemic lupus erythematosus skin lesions.

Objective: To analyze cytokine gene expression in keratinocytes from patients with systemic lupus erythematosus (SLE).

Introduction: Keratinocytes represent 95% of epidermal cells and can secrete several cytokines.

Methods: Keratinocytes were obtained by laser microdissection from 21 patients with SLE (10 discoid and 11 acute lesions) at involved and uninvolved sites.

Is autoimmune hepatitis a frequent finding among HCV patients with intense interface hepatitis?

Aim: To evaluate the overlap of autoimmune hepatitis in hepatitis C virus (HCV)-infected patients with intense interface hepatitis.

Methods: Among 1759 patients with hepatitis C submitted to liver biopsy, 92 (5.2%) presented intense interface hepatitis.

Decreased recent thymus emigrant number is associated with disease activity in systemic lupus erythematosus.

Objective: T cell receptor excision circle (TREC) is produced during T cell maturation within the thymus, and the number of TREC-bearing cells reflects the proportion of recent thymic emigrants in the peripheral lymphocyte pool. We studied TREC levels in peripheral CD4+ and CD8+ lymphocytes in patients with systemic lupus erythematosus (SLE) with quiescent and with active disease and in age- and sex-matched healthy volunteers.

Methods: TREC levels in peripheral CD4+ and CD8+ lymphocytes were determined in 29 patients with quiescent SLE, in 22 with active disease, and in 31 age- and sex-matched healthy volunteers.

Identification and complete sequencing of novel human transcripts through the use of mouse orthologs and testis cDNA sequences.

The correct identification of all human genes, and their derived transcripts, has not yet been achieved, and it remains one of the major aims of the worldwide genomics community. Computational programs suggest the existence of 30,000 to 40,000 human genes. However, definitive gene identification can only be achieved by experimental approaches.