Anti-VGLUT2 autoantibodies in neurological diseases.

Autoantibodies are important biomarkers for the diagnosis of autoimmune diseases that help to determine treatment strategies and to understand disease pathology. Despite the increasing numbers of neuronal autoantibody discoveries, there are still patients presenting with neurological autoimmune diseases and so far uncharacterized autoantibodies. Between 12/2016 and 06/2024, we collected sera of 314 patients with a distinct uncharacterized IgG pattern in neuronal tissue indirect immunofluorescence assay (IIFA).

Identification of nuclear valosin-containing-protein-like as a target of anti-nuclear autoantibodies in systemic sclerosis.

Objective: To identify the target antigen of an anti-nuclear autoantibody (ANA) from a patient with a suspected systemic autoimmune disease and to study the autoantibody's clinical association.

Methods: The index patient serum was screened for autoantibodies using indirect immunofluorescence assay (IFA) and line blots (membrane strips coated with parallel lines of different purified antigens). Immunoprecipitation with fixed HEp-2 cells followed by SDS-PAGE and MALDI-TOF mass spectrometry was used to identify the autoantigen, which was verified by competitive inhibition experiments, recombinant HEK293 cell-based IFA, and Western and line blots based on the recombinant antigen.

Identification of DAGLA as an autoantibody target in cerebellar ataxia.

Background: We aimed to investigate the clinical, imaging and fluid biomarker characteristics in patients with antidiacylglycerol lipase alpha (DAGLA)-autoantibody-associated cerebellitis.

Methods: Serum and cerebrospinal fliud (CSF) samples from four index patients were subjected to comprehensive autoantibody screening by indirect immunofluorescence assay (IIFA). Immunoprecipitation, mass spectrometry and recombinant protein assays were used to identify the autoantigen.

Bullous pemphigoid induced by IgG targeting type XVII collagen non-NC16A/NC15A extracellular domains is driven by Fc gamma receptor- and complement-mediated effector mechanisms and is ameliorated by neonatal Fc receptor blockade.

Bullous pemphigoid (BP) is an autoimmune blistering disease characterized by autoantibodies targeting type XVII collagen (Col17) with the noncollagenous 16A (NC16A) ectodomain representing the immunodominant site. The role of additional extracellular targets of Col17 outside NC16A has not been unequivocally demonstrated. In this study, we showed that Col17 ectodomain-reactive patient sera depleted in NC16A IgG induced dermal-epidermal separation in a cryosection model indicating the pathogenic potential of anti-Col17 non-NC16A extracellular IgG.

Septin-3 autoimmunity in patients with paraneoplastic cerebellar ataxia.

Background: Septins are cytoskeletal proteins with filament forming capabilities, which have multiple roles during cell division, cellular polarization, morphogenesis, and membrane trafficking. Autoantibodies against septin-5 are associated with non-paraneoplastic cerebellar ataxia, and autoantibodies against septin-7 with encephalopathy with prominent neuropsychiatric features. Here, we report on newly identified autoantibodies against septin-3 in patients with paraneoplastic cerebellar ataxia.

Allele-dependent interaction of LRRK2 and NOD2 in leprosy.

Leprosy, caused by Mycobacterium leprae, rarely affects children younger than 5 years. Here, we studied a multiplex leprosy family that included monozygotic twins aged 22 months suffering from paucibacillary leprosy. Whole genome sequencing identified three amino acid mutations previously associated with Crohn's disease and Parkinson's disease as candidate variants for early onset leprosy: LRRK2 N551K, R1398H and NOD2 R702W.

Inflammatory Monocyte Counts Determine Venous Blood Clot Formation and Resolution.

Background: Monocytes are thought to be involved in venous thrombosis but the role of individual monocyte subpopulations on thrombus formation, clot inflammation, and degradation is an important unresolved issue. We investigate the role of inflammatory Ly6C monocytes in deep vein thrombosis and their potential therapeutic impact.

Methods: Frequencies and compositions of blood monocytes were analyzed by flow cytometry in CCR2 (C-C chemokine receptor type 2) and wild-type mice of different ages and after treatment with the NR4A1 (nuclear receptor group 4 family A member 1, Nur77) agonist CnsB (cytosporone B).

Identification of novel proteins and mRNAs differentially bound to the Leishmania Poly(A) Binding Proteins reveals a direct association between PABP1, the RNA-binding protein RBP23 and mRNAs encoding ribosomal proteins.

Poly(A) Binding Proteins (PABPs) are major eukaryotic RNA-binding proteins (RBPs) with multiple roles associated with mRNA stability and translation and characterized mainly from multicellular organisms and yeasts. A variable number of PABP homologues are seen in different organisms however the biological reasons for multiple PABPs are generally not well understood. In the unicellular Leishmania, dependent on post-transcriptional mechanisms for the control of its gene expression, three distinct PABPs are found, with yet undefined functional distinctions.

Factors predicting failure of internal fixations of fractures of the lower limbs: a prospective cohort study.

Background: We assessed predictive factors of patients with fractures of the lower extremities caused by trauma. We examined which factors are associated with an increased risk of failure. Furthermore, the predictive factors were set into context with other long-term outcomes, concrete pain and physical functioning.

A new Trypanosoma cruzi genotyping method enables high resolution evolutionary analyses.

Background: Trypanosoma cruzi is an important human pathogen in Latin America with nearly seven million people infected. It has a large degree of genetic diversity, classified into six discrete typing units (DTUs), which probably influences its physiological behavior and clinical manifestations. Several genotyping methods are available, with distinct performance on easiness, cost, resolution and applicability; no method excels in all parameters.

Pathogenic Activation and Therapeutic Blockage of FcαR-Expressing Polymorphonuclear Leukocytes in IgA Pemphigus.

Pathomechanisms in IgA pemphigus are assumed to rely on Fc-dependent cellular activation by antigen-specific IgA autoantibodies; however, models for the disease and more detailed pathophysiologic data are lacking. In this study, we aimed to establish in vitro models of disease for IgA pemphigus, allowing us to study the effects of the interaction of anti-keratinocyte IgA with cell surface FcαRs. Employing multiple in vitro assays, such as a skin cryosection assay and a human skin organ culture model, in this study, we present mechanistic data for the pathogenesis of IgA pemphigus, mediated by anti-desmoglein 3 IgA autoantibodies.

Differential Binding of Autoantibodies to MOG Isoforms in Inflammatory Demyelinating Diseases.

Objective: To analyze serum immunoglobulin G (IgG) antibodies to major isoforms of myelin oligodendrocyte glycoprotein (MOG-alpha 1-3 and beta 1-3) in patients with inflammatory demyelinating diseases.

Methods: Retrospective case-control study using 378 serum samples from patients with multiple sclerosis (MS), patients with non-MS demyelinating disease, and healthy controls with MOG alpha-1-IgG positive (n = 202) or negative serostatus (n = 176). Samples were analyzed for their reactivity to human, mouse, and rat MOG isoforms with and without mutations in the extracellular MOG Ig domain (MOG-ecIgD), soluble MOG-ecIgD, and myelin from multiple species using live cell-based, tissue immunofluorescence assays and ELISA.

Autoantibodies Against the Purkinje Cell Protein RGS8 in Paraneoplastic Cerebellar Syndrome.

Objective: To describe the identification of regulator of G-protein signaling 8 (RGS8) as an autoantibody target in patients with cerebellar syndrome associated with lymphoma.

Methods: Sera of 4 patients with a very similar unclassified reactivity against cerebellar Purkinje cells were used in antigen identification experiments. Immunoprecipitations with cerebellar lysates followed by mass spectrometry identified the autoantigen, which was verified by recombinant immunofluorescence assay, immunoblot, and ELISA with the recombinant protein.

GTPase Regulator Associated with Focal Adhesion Kinase 1 (GRAF1) Immunoglobulin-Associated Ataxia and Neuropathy.

Background: To date, 10 patients with GTPase Regulator Associated with Focal Adhesion Kinase 1/Rho GTPase Activating Protein 26-Immunoglobulin (GRAF1/ARHGAP26-IgG) associated neurological disorders have been described, most with ataxia.

Objective: To report the clinical, oncological, and radiological associations of GRAF1 autoantibodies.

Methods: We identified 17 patients whose serum and/or cerebrospinal fluid IgG was confirmed to target GRAF1/ARHGAP26-IgG by both tissue-based immunofluorescence and transfected cell-based assay.

Elective removal vs. retaining of hardware after osteosynthesis in asymptomatic patients-a scoping review.

Background: Osteosynthesis is the internal fixation of fractures or osteotomy by mechanical devices (also called hardware). After bone healing, there are two options: one is to remove the hardware, the other is to leave it in place. The removal of the hardware in patients without medical indication (elective) is controversially discussed.

Contactin-1 autoimmunity: Serologic, neurologic, and pathologic correlates.

Objective: To determine serologic characteristics, frequency, phenotype, paraneoplastic associations, and electrodiagnostic and histopathologic features accompanying contactin-1 autoimmunity.

Methods: Archived sera known to produce synaptic tissue-based immunofluorescence patterns were reevaluated, and contactin-1 specificity was confirmed by recombinant protein assays. Screening of 233 chronic/relapsing demyelinating neuropathies for additional cases was performed.

Evaluating the re-identification risk of a clinical study report anonymized under EMA Policy 0070 and Health Canada Regulations.

Background: Regulatory agencies, such as the European Medicines Agency and Health Canada, are requiring the public sharing of clinical trial reports that are used to make drug approval decisions. Both agencies have provided guidance for the quantitative anonymization of these clinical reports before they are shared. There is limited empirical information on the effectiveness of this approach in protecting patient privacy for clinical trial data.

International multicenter examination of MOG antibody assays.

Objective: To compare the reproducibility of 11 antibody assays for immunoglobulin (Ig) G and IgM myelin oligodendrocyte glycoprotein antibodies (MOG-IgG and MOG-IgM) from 5 international centers.

Methods: The following samples were analyzed: MOG-IgG clearly positive sera (n = 39), MOG-IgG low positive sera (n = 39), borderline negative sera (n = 13), clearly negative sera (n = 40), and healthy blood donors (n = 30). As technical controls, 18 replicates (9 MOG-IgG positive and 9 negative) were included.

Multicenter prospective study on multivariant diagnostics of autoimmune bullous dermatoses using the BIOCHIP technology.

Background: The current standard in the serologic diagnosis of autoimmune bullous diseases (AIBD) is a multistep procedure sequentially applying different assays. In contrast, the BIOCHIP Mosaic technology combines multiple substrates for parallel analysis by indirect immunofluorescence.

Methods: Sera from 749 consecutive, prospectively recruited patients with direct immunofluorescence-positive AIBD from 13 international study centers were analyzed independently and blinded by using (1) a BIOCHIP Mosaic including primate esophagus, salt-split skin, rat bladder, monkey liver, monkey liver with serosa, recombinant BP180 NC16A, and gliadin GAF3X, as well as HEK293 cells expressing recombinant desmoglein 1, desmoglein 3, type VII collagen, and BP230 C-terminus and (2) the conventional multistep approach of the Department of Dermatology, University of Lübeck.

Serological Diagnosis of Autoimmune Bullous Skin Diseases.

Autoimmune bullous dermatoses (AIBD) encompass a variety of organ-specific autoimmune diseases that manifest with cutaneous and/or mucosal blisters and erosions. They are characterized by autoantibodies targeting structural proteins of the skin, which are responsible for the intercellular contact between epidermal keratinocytes and for adhesion of the basal keratinocytes to the dermis. The autoantibodies disrupt the adhesive functions, leading to splitting and blister formation.

GABA receptor autoimmunity: A multicenter experience.

Objective: We sought to validate methods for detection and confirmation of GABA receptor (R)-IgG and clinically characterize seropositive cases.

Methods: Archived serum and CSF specimens (185 total) suspected to harbor GABAR-IgG were evaluated by indirect immunofluorescence assay (IFA). Twenty-six specimens from 19 patients appeared suspicious for GABAR-IgG positivity by IFA, based on prior reports and comparison with commercial GABAR antibody staining.

Risk factors for complications and adverse outcomes in polytrauma patients with associated upper extremity injuries.

Background: In terms of upper extremity fractures by patients with multiple injuires, a lot of studies have assessed the functional outcome following trauma to have less favorable outcomes in regards to functional recovery. We tested the hypothesis that differences in clinical outcome occur between shaft and articular injuries of the upper extremity, when patients that sustained neurologic deficits (e.g.

High prevalence of bacteria in clinically aseptic non-unions of the tibia and the femur in tissue biopsies.

Purpose: There are several hints that bacterial colonization might be an often overseen cause of non-union. Modern procedures like PCR have been reported to diagnose bacterial colonization with a high degree of accuracy. While PCR is not ubiquitously available, we hypothesize that biopsies from the non-union site are comparable to PCR results reported in the literature.