Search results for "autoantibody"

Cross-reactivity of a pathogenic autoantibody to a tumor antigen in GABA(A) receptor encephalitis

2021

Encephalitis associated with antibodies against the neuronal gamma-aminobutyric acid A receptor (GABA A -R) is a rare form of autoimmune encephalitis. The pathogenesis is still unknown but autoimmune mechanisms were surmised. Here we identified a strongly expanded B cell clone in the cerebrospinal fluid of a patient with GABA A -R encephalitis. We expressed the antibody produced by it and showed by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry that it recognizes the GABA A -R. Patch-clamp recordings revealed that it tones down inhibitory synaptic transmission and causes increased excitability of hippocampal CA1 pyramidal neurons. Thus, the antibody likely contributed to…

Autoimmunity seen through the SEREX-scope.

2003

Autoantibodies can be detected in autoimmune diseases with a long prodromal phase and may serve as early indicators of disease activity. Autoantibody-based screening methods are therefore potent tools for the identification of target antigens. The SEREX method (serological identification of antigens by recombinant expression cloning) has been developed for the serological definition of immunogenic tumor antigens. Recent studies indicate that the SEREX approach may also be utilized for the analysis of complex immune responses involved in autoimmune diseases.

Label-free piezoelectric biosensor for prognosis and diagnosis of Systemic Lupus Erythematosus

2017

[EN] An autoantigen piezoelectric sensor to quantify specific circulating autoantibodies in human serum is developed. The sensor consisted on a quartz crystal microbalance with dissipation monitoring (QCM-D) where TRIM21 and TROVE2 autoantigens were covalently immobilized, allowing the selective determination of autoantibodies for diagnosis and prognosis of Systemic Lupus Erythematosus (SLE). The sensitivity of the biosensor, measured as IC50 value, was 1.51 U/mL and 0.32 U/mL, for anti-TRIM21 and anti-TROVE2 circulating autoantibodies, respectively. The sensor is also able to establish a structural interaction fingerprint pattern or profile of circulating autoantibodies, what allows scorin…

Anti-C1q Autoantibodies in Lupus Nephritis: Prevalence and Clinical Significance

2005

Recently, anti-C1q autoantibodies have been proposed as a useful marker in systemic lupus erythematosus (SLE) since their occurrence correlates with renal involvement and, possibly, with nephritic activity. We aimed to evaluate the prevalence of anti-C1q antibodies in patients with SLE, with and without renal involvement, and to correlate these markers' presence and levels with the activity of the disease and nephropathy. We studied 61 patients with SLE, 40 of whom had biopsy-proven lupus nephritis; 35 patients with other connective tissue diseases; and 54 healthy controls. In addition, 18 lupus nephritis patients were followed up during the disease time course. Anti-C1q antibodies were mea…

Biosensor Analysis of β2-Glycoprotein I–Reactive Autoantibodies: Evidence for Isotype-Specific Binding and Differentiation of Pathogenic from Infecti…

2007

Abstract Background: For the laboratory diagnosis of the antiphospholipid syndrome (APS) we developed a biosensor with the ability to distinguish between disease-relevant anti-β2-glycoprotein I (β2GPI) autoantibodies (anti-β2GPI) and pathogen-specific β2GPI cross-reactive antibodies that occur transiently during infections. Methods: We used a surface plasmon resonance (SPR) biosensor device. For the detection of anti-β2GPI in serum samples, affinity-purified human β2GPI was covalently attached to a functionalized n-alkanethiol self-assembling monolayer on the biosensor chip. After verifying the specificity of the biosensor system with a panel of monoclonal antibodies to β2GPI, we analyzed s…

2004

Here we present a comprehensive molecular mapping of virus-induced autoimmune B cell responses obtained by serological identification of antigens by recombinant expression cloning analysis. Immunoscreening of cDNA expression libraries of various organs (lung, liver, and spleen) using sera from mice infected with cytopathic (vaccinia virus [VV]) or noncytopathic (lymphocytic choriomeningitis virus [LCMV]) viruses revealed a broad specificity of the elicited autoantibody response. Interestingly, the majority of the identified autoantigens have been previously described as autoantigens in humans. We found that induction of virus-induced autoantibodies of the immunoglobulin G class largely depe…

Identification of Tumor-Associated Autoantigens With SEREX

2004

Serological analysis of tumor antigens by recombinant cDNA expression cloning (SEREX) allows the systematic cloning of tumor antigens recognized by the spontaneous autoantibody repertoire of cancer patients. For SEREX, cDNA expression libraries are constructed from fresh tumor specimens, packaged into lambda-phage vectors, and expressed recombinantly in Escherichia coli. Recombinant proteins expressed during the lytic infection of bacteria are transferred onto nitrocellulose membranes to be probed with diluted autologous patient serum for identification of clones reactive with high-titered IgG antibodies. This chapter describes the SEREX technology in detail.

Evaluation of Clotting Factor Concentrates for Treatment of Thrombotic Thrombocytopenic Purpura.

2010

Abstract Abstract 3678 Introduction: Thrombotic thrombocytopenic purpura (TTP) is characterized by microthrombi, hemolytic anemia as well as thrombocytopenia. These symptoms are caused by a decreased activity of the protease ADAMTS13 which cleaves the von Willebrand Factor (VWF), due to mutation of the ADAMTS13-gene or autoantibodies. At the moment, the only available immediate therapy is plasmapheresis with Fresh Frozen Plasma (FFP) which may induce side effects. Therefore an alternative therapy might be the treatment with clotting factor concentrates. Methods: 40 plasma samples were tested, consisting of FFP and solvent/detergent treated plasma, four batches of each blood group; VWF/VIII …

Autoantibody Inhibitor Eradication In Acquired Hemophilia Associated with Cancer: a Retrospective Analysis

2010

Abstract Abstract 1418 Introduction: Acquired hemophilia (AH), a rare autoimmune disorder primarily of adults, is typically characterized by the presence of IgG oligoclonal antibodies to the clotting factor VIII protein (FVIII). About 10–15% of patients with AH have an underlying malignancy, but the etiologic relationship of cancer to formation of FVIII inhibitor is yet to be determined. To date, there have been no published, comprehensive reviews on the efficacy of various treatments for AH in the context of either solid tumor or hematologic malignancies. Therefore, we have systematically reviewed 86 patients with cancer-associated AH from our own cancer center and from the published liter…

Precise mapping of the Goodpasture epitope(s) using phage display, site-directed mutagenesis, and surface plasmon resonance.

2013

Goodpasture disease is an autoimmune disorder mediated by circulating autoantibodies against the noncollagenous-1 (NC1) domain of the alpha 3 chain of type IV collagen (alpha 3(IV)NC1). The structure of Goodpasture epitope(s) has been previously mapped into two main binding regions (E-A and E-B) of the alpha 3(IV)NC1 domain using a residue mutation approach on the highly related alpha 1(IV)NC1 domain. Here we combined phage display and surface plasmon resonance technology to more precisely localize the pathogenic binding sites. Peptides mimicking the Goodpasture epitope(s) were used to identify residues involved in autoantibody binding and found involvement of eight residues previously unre…