Cross-reactivity of a pathogenic autoantibody to a tumor antigen in GABAA receptor encephalitis

Encephalitis associated with antibodies against the neuronal gamma-aminobutyric acid A receptor (GABAA-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 GABAA-R encephalitis. We expressed the antibody produced by it and showed by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry that it recognizes the GABAA-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 clinical disease symptoms. Hybridization to a protein array revealed the cross-reactive protein LIM-domain-only protein 5 (LMO5), which is related to cell-cycle regulation and tumor growth. We confirmed LMO5 recognition by immunoprecipitation and ELISA and showed that cerebrospinal fluid samples from two other patients with GABAA-R encephalitis also recognized LMO5. This suggests that cross-reactivity between GABAA-R and LMO5 is frequent in GABAA-R encephalitis and supports the hypothesis of a paraneoplastic etiology.

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DETECTION OF CASPASE-3, NEURON SPECIFIC ENOLASE, AND HIGH-AENSITIVITY C-REACTIVE PROTEIN LEVELS IN BOTH CEREBROSPINAL FLUID AND SERUM OF PATIENTS AFTER ANEURYSMAL SUBARACHNOID HEMORRHAGE

Neurosurgery ◽

10.1227/01.neu.0000255394.77538.bb ◽

2007 ◽

Vol 60 (4) ◽

pp. 674-680 ◽

Cited By ~ 19

Author(s):

Tibet Kacira ◽

Rahsan Kemerdere ◽

Pinar Atukeren ◽

Hakan Hanimoglu ◽

Galip Zihni Sanus ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Subarachnoid Hemorrhage ◽

Caspase 3 ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Neuron Specific Enolase ◽

Enzyme Linked Immunosorbent Assay ◽

Prospective Clinical Study ◽

C Reactive Protein ◽

Reactive Protein ◽

Number Of Patients

Abstract OBJECTIVE The purpose of this study is to explore whether or not the levels of caspase-3 (Casp3), neuron-specific enolase (NSE), and high-sensitivity C-reactive protein (hsCRP) were elevated in cerebrospinal fluid (CSF) and serum of patients after aneurysmal subarachnoid hemorrhage (SAH). METHODS This prospective clinical study consisted of 20 patients who experienced recent aneurysmal SAH and 15 control patients who experienced hydrocephalus without any other central nervous system disease. CSF and serum samples obtained within the first 3 days, and on the fifth and seventh days of SAH were assayed for Casp3, NSE, and hsCRP by using enzyme-linked immunosorbent assay. RESULTS Levels of Casp3, NSE, and hsCRP in the CSF (P = 0.00001, P = 0.00001, and P <0.003, respectively) and in the serum (P = 0.00001, P <0.01, and P = 0.00001, respectively) of SAH patients were found to be elevated when compared with controls with normal pressure hydrocephalus. CONCLUSION The authors have demonstrated the synchronized elevation of Casp3, NSE, and hsCRP in both CSF and serum of patients with aneurysmal SAH. Further studies with a large number of patients are recommended to more accurately determine the roles of these molecules in aneurysmal SAH.

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Noradrenaline, Serotonin, GABA, and Glycine in Cerebrospinal Fluid during Labor Pain: A Cross-Sectional Prospective Study

Pain Research and Management ◽

10.1155/2017/2752658 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Pornpan Chalermkitpanit ◽

Atikun Thonnagith ◽

Phatthanaphol Engsusophon ◽

Somrat Charuluxananan ◽

Sittisak Honsawek

Keyword(s):

Cerebrospinal Fluid ◽

Rating Scale ◽

Visceral Pain ◽

Numerical Rating Scale ◽

Labor Pain ◽

Enzyme Linked Immunosorbent Assay ◽

Control Group ◽

Gamma Aminobutyric Acid ◽

Cross Sectional ◽

Pain Scores

Background and Aims. The inhibitory pathways that play a role in spinal modulation include local interneurons and descending control. Clinical data regarding the role of these pathways in acute pain is lacking. Accordingly, the aim of this study was to evaluate cerebrospinal fluid (CSF) levels of noradrenaline, serotonin, gamma-aminobutyric acid (GABA), and glycine in parturients with labor pain compared to those without labor pain.Methods. One hundred term uncomplicated pregnant women receiving spinal anesthesia for cesarean section were enrolled in this prospective cross-sectional study. CSF noradrenaline, serotonin, GABA, and glycine levels were analyzed by enzyme-linked immunosorbent assay. Labor pain score was assessed by numerical rating scale.Results. Median CSF serotonin concentration in parturients with labor pain was significantly lower than in those without pain (p<0.001). Median CSF glycine level in the labor pain group was significantly higher than in the control group (p<0.001). There were no significant differences in median CSF level of noradrenaline or GABA between parturients with and without labor pain. Subsequent analysis showed labor pain scores to be negatively correlated with CSF serotonin (r=-0.217,p=0.04) but positively correlated with CSF glycine (r=0.415,p<0.001).Conclusion. CSF serotonin and glycine were significantly correlated with labor pain scores. These findings suggest that the serotonergic and glycinergic systems may play a role in spinal modulation of visceral pain.

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753. Performance Characteristics of Diagnostic Assays in Blastomycosis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.943 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S424-S424

Author(s):

Timothy O’Dowd ◽

Jack McHugh ◽

Nancy Wengenack ◽

Elitza Theel ◽

Paschalis Vergidis

Keyword(s):

Granulomatous Inflammation ◽

Cross Reactivity ◽

Performance Characteristics ◽

Enzyme Linked Immunosorbent Assay ◽

Fungal Culture ◽

Noninvasive Test ◽

Serum Antigen ◽

Urine Antigen ◽

Antigen Tests ◽

Urine And Serum

Abstract Background Blastomycosis has historically been a difficult diagnosis to establish, often initially misdiagnosed as bacterial pneumonia. Serologic assays and polymerase chain reaction (PCR) tests are available, but their performance is not well defined. The objective of this study was to characterize their performance. Methods Subjects were identified via chart review of patients diagnosed with blastomycosis from 2005 to 2020. A definitive diagnosis was based on fungal culture, histopathology, or cytology. Performance characteristics of the Blastomyces antibody enzyme linked immunosorbent assay (ELISA), immunodiffusion (ID), complement fixation (CF), urine and serum antigen ELISAs, and PCR were evaluated in patients with confirmed blastomycosis. Data on patient demographics, location of disease, and mortality was also collected. Results We identified 193 patients with blastomycosis. The mean age was 51.8 years (range, 11-84) and 73.6% of patients were male. 42.5% resided in Minnesota, 18.1% in Wisconsin, and 12.9% in Iowa. Diagnosis was based on culture in 142 (73.2%) or histopathology/cytology in 67 (34.7%) patients. Granulomatous inflammation was present in 73.1% (38/52) while 21.2% (41/193) had evidence of extrapulmonary dissemination. The antibody, ID, and CF assays were positive in 43.5% (37/85), 35.1% (33/94) and 20.5% (8/39) of patients, respectively. Sensitivity of Blastomyces PCR was 40% (4/10) in sputum and 75% (21/28) in bronchoalveolar lavage (BAL) fluid. Blastomyces urine and serum antigen tests were positive in 68% (34/50) and 50% (9/18) of cases, respectively, while the urine antigen was positive in 63.6% (7/11) of disseminated cases. Patients had a positive Histoplasma urine antigen test in 54.1% (20/37) and Aspergillus galactomannan in BAL in 34.8% (8/23) of cases. Serum beta-D-glucan test was positive in 16.7% (2/12). 90-day mortality was 21/193 (10.9%) and median time from diagnosis to death was 18 days. Conclusion In this cohort, Blastomyces urine antigen was the most sensitive noninvasive test, with similar performance in pulmonary and disseminated disease. However, its utility is limited by poor specificity due to cross-reactivity. Blastomyces PCR from BAL fluid demonstrated the highest sensitivity. Blastomyces antibody, ID, and CF had poor sensitivity. Disclosures All Authors: No reported disclosures

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Characterization of the Diagnostic Performance of a Novel COVID-19 PETIA in Comparison to Four Routine N-, S- and RBD-Antigen Based Immunoassays

Diagnostics ◽

10.3390/diagnostics11081332 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1332

Author(s):

Alexander Spaeth ◽

Thomas Masetto ◽

Jessica Brehm ◽

Leoni Wey ◽

Christian Kochem ◽

...

Keyword(s):

Immune Response ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Chemiluminescence Immunoassay ◽

Face To Face ◽

Comprehensive Comparison ◽

Broad Variety ◽

Viral Responses ◽

Novel Coronavirus ◽

High Consistency

In 2019, a novel coronavirus emerged in Wuhan in the province of Hubei, China. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) quickly spread across the globe, causing the neoteric COVID-19 pandemic. SARS-CoV-2 is commonly transmitted by droplet infection and aerosols when coughing or sneezing, as well as high-risk exposures to infected individuals by face-to-face contact without protective gear. To date, a broad variety of techniques have emerged to assess and quantify the specific antibody response of a patient towards a SARS-CoV-2 infection. Here, we report the first comprehensive comparison of five different assay systems: Enzyme-Linked Immunosorbent Assay (ELISA), Chemiluminescence Immunoassay (CLIA), Electro-Chemiluminescence Immunoassay (ECLIA), and a new Particle-Enhanced Turbidimetric Immunoassay (PETIA) for SARS-CoV-2. Furthermore, we also evaluated the suitability of N-, S1- and RBD-antigens for quantifying the SARS-CoV-2 specific immune response. Linearity and precision, overall sensitivity and specificity of the assays, stability of samples, and cross-reactivity of general viral responses, as well as common coronaviruses, were assessed. Moreover, the reactivity of all tests to seroconversion and different sample matrices was quantified. All five assays showed good overall agreement, with 76% and 87% similarity for negative and positive samples, respectively. In conclusion, all evaluated methods showed a high consistency of results and suitability for the robust quantification of the SARS-CoV-2-derived immune response.

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Early Inflammatory Cytokine Expression in Cerebrospinal Fluid of Patients with Spontaneous Intraventricular Hemorrhage

Biomolecules ◽

10.3390/biom11081123 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1123

Author(s):

Wendy C. Ziai ◽

Adrian R. Parry-Jones ◽

Carol B. Thompson ◽

Lauren H. Sansing ◽

Michael T. Mullen ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Intraventricular Hemorrhage ◽

Inflammatory Responses ◽

Obstructive Hydrocephalus ◽

External Ventricular Drainage ◽

Enzyme Linked Immunosorbent Assay ◽

Injury Reduction ◽

Positive Correlations ◽

Factor Α ◽

Perihematomal Edema

We investigated cerebrospinal fluid (CSF) expression of inflammatory cytokines and their relationship with spontaneous intracerebral and intraventricular hemorrhage (ICH, IVH) and perihematomal edema (PHE) volumes in patients with acute IVH. Twenty-eight adults with IVH requiring external ventricular drainage for obstructive hydrocephalus had cerebrospinal fluid (CSF) collected for up to 10 days and had levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-8, IL-10, tumor necrosis factor-α (TNFα), and C-C motif chemokine ligand CCL2 measured using enzyme-linked immunosorbent assay. Median [IQR] ICH and IVH volumes at baseline (T0) were 19.8 [5.8–48.8] and 14.3 [5.3–38] mL respectively. Mean levels of IL-1β, IL-6, IL-10, TNF-α, and CCL2 peaked early compared to day 9–10 (p < 0.05) and decreased across subsequent time periods. Levels of IL-1β, IL-6, IL-8, IL-10, and CCL2 had positive correlations with IVH volume at days 3–8 whereas positive correlations with ICH volume occurred earlier at day 1–2. Significant correlations were found with PHE volume for IL-6, IL-10 and CCL2 at day 1–2 and with relative PHE at days 7–8 or 9–10 for IL-1β, IL-6, IL-8, and IL-10. Time trends of CSF cytokines support experimental data suggesting association of cerebral inflammatory responses with ICH/IVH severity. Pro-inflammatory markers are potential targets for injury reduction.

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Cerebrospinal Fluid Chitinases as Biomarkers for Amyotrophic Lateral Sclerosis

Diagnostics ◽

10.3390/diagnostics11071210 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1210

Author(s):

Júlia Costa ◽

Marta Gromicho ◽

Ana Pronto-Laborinho ◽

Conceição Almeida ◽

Ricardo A. Gomes ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Cerebrospinal Fluid ◽

Motor Neurons ◽

Neurological Diseases ◽

Disease Diagnosis ◽

Enzyme Linked Immunosorbent Assay ◽

Progression Rate ◽

Therapeutic Trials ◽

Als Patients ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative neuromuscular disease that affects motor neurons controlling voluntary muscles. Survival is usually 2–5 years after onset, and death occurs due to respiratory failure. The identification of biomarkers would be very useful to help in disease diagnosis and for patient stratification based on, e.g., progression rate, with implications in therapeutic trials. Neurofilaments constitute already-promising markers for ALS and, recently, chitinases have emerged as novel marker targets for the disease. Here, we investigated cerebrospinal fluid (CSF) chitinases as potential markers for ALS. Chitotriosidase (CHIT1), chitinase-3-like protein 1 (CHI3L1), chitinase-3-like protein 2 (CHI3L2) and the benchmark marker phosphoneurofilament heavy chain (pNFH) were quantified by an enzyme-linked immunosorbent assay (ELISA) from the CSF of 34 ALS patients and 24 control patients with other neurological diseases. CSF was also analyzed by UHPLC-mass spectrometry. All three chitinases, as well as pNFH, were found to correlate with disease progression rate. Furthermore, CHIT1 was elevated in ALS patients with high diagnostic performance, as was pNFH. On the other hand, CHIT1 correlated with forced vital capacity (FVC). The three chitinases correlated with pNFH, indicating a relation between degeneration and neuroinflammation. In conclusion, our results supported the value of CHIT1 as a diagnostic and progression rate biomarker, and its potential as respiratory function marker. The results opened novel perspectives to explore chitinases as biomarkers and their functional relevance in ALS.

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Aptamer BC 007’s Affinity to Specific and Less-Specific Anti-SARS-CoV-2 Neutralizing Antibodies

Viruses ◽

10.3390/v13050932 ◽

2021 ◽

Vol 13 (5) ◽

pp. 932

Author(s):

Annekathrin Haberland ◽

Oxana Krylova ◽

Heike Nikolenko ◽

Peter Göttel ◽

Andre Dallmann ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Resonance Spectroscopy ◽

Plastic Plate ◽

Calorimetric Titration ◽

Background Signal ◽

High Background ◽

Specific Virus ◽

Binding Sequence

COVID-19 is a pandemic respiratory disease that is caused by the highly infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Anti-SARS-CoV-2 antibodies are essential weapons that a patient with COVID-19 has to combat the disease. When now repurposing a drug, namely an aptamer that interacts with SARS-CoV-2 proteins for COVID-19 treatment (BC 007), which is, however, a neutralizer of pathogenic autoantibodies in its original indication, the possibility of also binding and neutralizing anti-SARS-CoV-2 antibodies must be considered. Here, the highly specific virus-neutralizing antibodies have to be distinguished from the ones that also show cross-reactivity to tissues. The last-mentioned could be the origin of the widely reported SARS-CoV-2-induced autoimmunity, which should also become a target of therapy. We, therefore, used enzyme-linked immunosorbent assay (ELISA) technology to assess the binding of well-characterized publicly accessible anti-SARS-CoV-2 antibodies (CV07-209 and CV07-270) with BC 007. Nuclear magnetic resonance spectroscopy, isothermal calorimetric titration, and circular dichroism spectroscopy were additionally used to test the binding of BC 007 to DNA-binding sequence segments of these antibodies. BC 007 did not bind to the highly specific neutralizing anti-SARS-CoV-2 antibody but did bind to the less specific one. This, however, was a lot less compared to an autoantibody of its original indication (14.2%, range 11.0–21.5%). It was also interesting to see that the less-specific anti-SARS-CoV-2 antibody also showed a high background signal in the ELISA (binding on NeutrAvidin-coated or activated but noncoated plastic plate). These initial experiments suggest that the risk of binding and neutralizing highly specific anti-SARS CoV-2 antibodies by BC 007 should be low.

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Dogs as Sentinels for Flavivirus Exposure in Urban, Peri-Urban and Rural Hanoi, Vietnam

Viruses ◽

10.3390/v13030507 ◽

2021 ◽

Vol 13 (3) ◽

pp. 507

Author(s):

Long Pham-Thanh ◽

Thang Nguyen-Tien ◽

Ulf Magnusson ◽

Vuong Bui-Nghia ◽

Anh Bui-Ngoc ◽

...

Keyword(s):

Mosquito Control ◽

Risk Mitigation ◽

Significant Risk ◽

Cross Sectional Study ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Cross Sectional ◽

Major Health ◽

Household Level

Diseases caused by flaviviruses, including dengue fever and Japanese encephalitis, are major health problems in Vietnam. This cross-sectional study explored the feasibility of domestic dogs as sentinels to better understand risks of mosquito-borne diseases in Hanoi city. A total of 475 dogs serum samples from 221 households in six districts of Hanoi were analyzed by a competitive enzyme-linked immunosorbent assay (cELISA) for antibodies to the pr-E protein of West Nile virus and other flaviviruses due to cross-reactivity. The overall flavivirus seroprevalence in the dog population was 70.7% (95% CI = 66.4–74.8%). At the animal level, significant associations between seropositive dogs and district location, age, breed and keeping practice were determined. At the household level, the major risk factors were rural and peri-urban locations, presence of pigs, coil burning and households without mosquito-borne disease experience (p < 0.05). Mosquito control by using larvicides or electric traps could lower seropositivity, but other measures did not contribute to significant risk mitigation of flavivirus exposure in dogs. These results will support better control of mosquito-borne diseases in Hanoi, and they indicate that dogs can be used as sentinels for flavivirus exposure.

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