43,318 results match your criteria antibody titers

Predicting the efficacy of COVID-19 convalescent plasma donor units with the Lumit Dx anti-receptor binding domain assay.

PLoS One 2021 26;16(7):e0253551. Epub 2021 Jul 26.

Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States of America.

Background: The novel coronavirus SARS-CoV2 that causes COVID-19 has resulted in the death of more than 2.5 million people, but no cure exists. Although passive immunization with COVID-19 convalescent plasma (CCP) provides a safe and viable therapeutic option, the selection of optimal units for therapy in a timely fashion remains a barrier. Read More

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Immunogenicity and safety of a recombinant fusion protein vaccine (V-01) against coronavirus disease 2019 in healthy adults: a randomized, double-blind, placebo-controlled, phase II trial.

Chin Med J (Engl) 2021 Jul 22. Epub 2021 Jul 22.

Guangdong Provincial Institute of Biological Products and Materia Medica, Guangzhou, Guangdong 510440, China Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong 511430, China Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China National Institutes for Food and Drug Control, Beijing 100050, China Gaozhou Center for Disease Control and Prevention, Maoming, Guangdong 525000, China Livzon Bio Inc., Zhuhai, Guangdong 519045, China Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital, Shenzhen, Guangdong 518112, China.

Background: Innovative coronavirus disease 2019 (COVID-19) vaccines, with elevated global manufacturing capacity, enhanced safety and efficacy, simplified dosing regimens, and distribution that is less cold chain-dependent, are still global imperatives for tackling the ongoing pandemic. A previous phase I trial indicated that the recombinant COVID-19 vaccine (V-01), which contains a fusion protein (IFN-PADRE-RBD-Fc dimer) as its antigen, is safe and well tolerated, capable of inducing rapid and robust immune responses, and warranted further testing in additional clinical trials. Herein, we aimed to assess the immunogenicity and safety of V-01, providing rationales of appropriate dose regimen for further efficacy study. Read More

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Humoral Response of Renal Transplant Recipients to the BNT162b2 SARS-CoV-2 mRNA Vaccine Using Both RBD IgG and Neutralizing Antibodies.

Transplantation 2021 Jul 6. Epub 2021 Jul 6.

Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.

Background: Data about SARS-CoV-2 vaccines efficacy in renal transplant recipients (RTR) is lacking.

Methods: To reveal predictors for humoral response to BNT162b2 vaccine among RTR, patients were divided to positive (N=42) and negative (N=78) response groups based on receptor-binding domain (RBD) IgG >= 1.1 and neutralizing antibodies (NA) >= 16 dilution versus RBD IgG < 1. Read More

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Increasing numbers of CD19 + CD24CD38 regulatory B cells and pre-germinal center B cells reflect activated autoimmunity and predict future treatment response in patients with untreated immune thrombocytopenia.

Int J Hematol 2021 Jul 26. Epub 2021 Jul 26.

Hematology, Graduate School of Medicine, Osaka City University, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.

The pathophysiology of immune thrombocytopenia (ITP) is poorly understood, particularly aspects regarding abnormal homeostasis and dysregulation of B cells. In this study, we analyzed peripheral lymphocyte subsets in patients with untreated ITP and healthy controls, and examined correlations between cell percentages/counts and titers of serum cytokines and antibodies. We also compared ITP patients who later required second-line therapies and those who did not. Read More

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Impact of SARS-CoV-2 variant-associated RBD mutations on the susceptibility to serum antibodies elicited by COVID-19 infection or vaccination.

Clin Infect Dis 2021 Jul 26. Epub 2021 Jul 26.

State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, People's Republic of China.

Background: Several SARS-CoV-2 lineages with mutations at the spike protein receptor binding domain (RBD) have reduced susceptibility to antibody neutralization, and have been classified as Variants of Concern (VOCs) or Variants of Interest (VOIs). Here, we systematically compared the neutralization susceptibility and RBD binding of different VOCs/VOIs, including B.1. Read More

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Convalescent Plasma Reduces Endogenous Antibody Response in COVID-19: A Retrospective Cross-Sectional Study.

Turk J Haematol 2021 Jul 26. Epub 2021 Jul 26.

Yıldırım Bayezıt University, School of Medicine, Department of Internal Medicine, Division of Rheumatology, Ankara, Turkey.

Objective: Aim of this study is to investigate post-COVID-19 antibody titers in patients who received convalescent plasma (CP) in addition to standard of care.

Materials And Methods: Hospitalized COVID-19 patients who received CP in addition to standard of care were retrospectively investigated. Patients who received CP with a recorded total COVID-19 antibody test result after treatment were included. Read More

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Sputnik V Vaccine Elicits Seroconversion and Neutralizing Capacity to SARS CoV-2 after a Single Dose.

Cell Rep Med 2021 Jul 9:100359. Epub 2021 Jul 9.

Hospital Interzonal Especializado de Agudos y Crónicos San Juan de Dios, Provincia de Buenos Aires, Argentina.

Massive vaccination offers great promise for halting the global COVID-19 pandemic. However, limited supply and uneven vaccine distribution create an urgent need to optimize vaccination strategies. We evaluate SARS-CoV-2-specific antibody responses after Sputnik V vaccination of healthcare workers in Argentina, measuring IgG anti-spike titers and neutralizing capacity after one and two doses in a cohort of naïve or previously infected volunteers. Read More

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Safety and Immunogenicity of a DNA SARS-CoV-2 vaccine (ZyCoV-D): Results of an open-label, non-randomized phase I part of phase I/II clinical study by intradermal route in healthy subjects in India.

EClinicalMedicine 2021 Aug 17;38:101020. Epub 2021 Jul 17.

Zydus Discovery DMCC, Dubai, United Arab Emirates.

Background: ZyCoV-D is a DNA vaccine candidate, which comprises a plasmid DNA carrying spike-S gene of SARS-CoV-2 virus along with gene coding for signal peptide. The spike(S) region includes the receptor-binding domain (RBD), which binds to the human angiotensin converting Enzyme (ACE)-2 receptor and mediates the entry of virus inside the cell.

Methods: We conducted a single-center, open-label, non-randomized, Phase 1 trial in India between July 2020 and October 2020. Read More

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Cognitive Impact by Blood Circulating Anti-NMDAR1 Autoantibodies.

Xianjin Zhou

J Psychiatr Brain Sci 2021 28;6. Epub 2021 Jun 28.

Department of Psychiatry, University of California San Diego, La Jolla, 92093, California, USA.

Antibodies persist months and years in blood. Chronic presence of low titers of blood circulating anti-NMDAR1 autoantibodies are sufficient to impair cognitive function in the integrity of the BBB in mice, suggesting potential cognitive damaging effects of low titers of blood circulating anti-NMDAR1 autoantibodies in the general human population and psychiatric patients. Investigation of anti-NMDAR1 autoantibodies against individual NMDAR1 antigenic epitopes may potentially provide risk biomarkers and therapeutic targets for development of immunotherapy as a precision medicine for psychiatric patients in the future. Read More

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Metastatic Malignant Struma Ovarii and Graves' Disease: A Rare Occurrence.

AACE Clin Case Rep 2021 Jul-Aug;7(4):243-246. Epub 2021 Jan 6.

Tan Tock Seng Hospital, Department of Endocrinology, Novena, Singapore.

Objective: Malignant struma ovarii (SO) is a rare condition. Although there have been a few reported cases of malignant SO with coexisting Graves' disease (GD), the exact incidence of metastasis in these cases is not known. We report a rare case of metastatic malignant SO coexisting with GD. Read More

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January 2021

Case Report: Hodgkin Lymphoma and Refractory Systemic Lupus Erythematosus Unveil Activated Phosphoinositide 3-Kinase-δ Syndrome 2 in an Adult Patient.

Front Pediatr 2021 8;9:702546. Epub 2021 Jul 8.

Pediatric Unit, Istituti di Ricovero e Cura a Carattere Scientifico Azienda Ospedaliero-Universitaria di Bologna, University of Bologna, Bologna, Italy.

Activated phosphoinositide 3-kinase-δ syndrome 2 (APDS2) is a rare primary immune regulatory disorder caused by heterozygous gain of function mutation in the gene encoding PI3Kδ regulatory p85α subunit and resulting in PI3Kδ hyperactivation. Clinical features range from recurrent infections to manifestations of immune dysregulation like autoimmunity, inflammation, systemic lymphoproliferation, and increased risk of cancer. We describe a new dominant mutation causing APDS2 presenting with lymphoma and systemic refractory autoimmunity. Read More

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Factors affecting recurrent positive RT-PCR results in clinically cured COVID-19 patients: a multicenter study.

Am J Transl Res 2021 15;13(6):6191-6199. Epub 2021 Jun 15.

Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University Wuhan 430060, Hubei, P. R. China.

The aim of this study was to evaluate factors affecting the recurrence of positive RT-PCR results. By performing a retrospective analysis, we evaluated the clinical data of recurrent positive coronavirus disease 2019 (COVID-19) patients in multiple medical institutions in Wuhan. We recruited COVID-19 patients who were hospitalized from January 1 to March 10, 2020, in three tertiary hospitals in Wuhan, met the discharge criteria and received at least one additional nucleic acid test before leaving the hospital. Read More

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Auto-Antibody Production During Experimental Atherosclerosis in Mice.

Front Immunol 2021 9;12:695220. Epub 2021 Jul 9.

Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD, United States.

Current models stipulate that B cells and antibodies function during atherosclerosis in two distinct ways based on antibody isotype, where IgM is protective and IgG is inflammatory. To examine this model, we generated mice, which are unable to produce IgG antibodies due to the absence of activation-induced deaminase (AID) but maintain high plasma cholesterol due to the absence of apolipoprotein E (APOE). We saw a dramatic decrease in plaque formation in mice compared to mice. Read More

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Pathogenic Role of Circulating Citrullinated Antigens and Anti-Cyclic Monoclonal Citrullinated Peptide Antibodies in Rheumatoid Arthritis.

Front Immunol 2021 30;12:692242. Epub 2021 Jun 30.

Clinical Immunology and Stem Cell Laboratory (CiSTEM) Laboratory, Catholic Induced Pluripotent Stem Cell (iPSC) Research Center, College of Medicine, The Catholic University of Korea, Seoul, South Korea.

We examined whether it is possible to directly detect citrullinated antigens in the serum of rheumatoid arthritis (RA) patients using a monoclonal antibody (mAb) designed to be specific for citrullinated peptides. In order to confirm the potential of the mAb as a direct arthritis-inducing substance through experimental model of RA, a monoclonal antibody (mAb) 12G1 was generated using by immunization of mice with a challenging cyclic citrullinated peptide. Immunohistochemical analysis of RA-affected synovial tissue showed that our mAb 12G1 could indeed detect citrullinated proteins in target tissues. Read More

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Impact of Thyroid Autoimmunity on Fertilization/Intracytoplasmic Sperm Injection Outcomes and Fetal Weight.

Front Endocrinol (Lausanne) 2021 8;12:698579. Epub 2021 Jul 8.

Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China.

Several studies have reported the association between thyroid autoimmunity (TAI) and fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes. However, the findings remain controversial. We performed a large-scale retrospective cohort study to verify the effect of the presence of thyroid antibodies on IVF/ICSI outcomes and fetal growth and to evaluate the association between the types and titers of thyroid antibodies and adverse IVF/ICSI outcomes. Read More

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An enveloped virus-like particle vaccine expressing a stabilized prefusion form of the SARS-CoV-2 spike protein elicits highly potent immunity.

Vaccine 2021 Jul 16. Epub 2021 Jul 16.

VBI Vaccines, 201-310 Hunt Club Road, Ottawa, ON K1V 1C1, Canada.

We evaluated enveloped virus-like particles (eVLPs) expressing various forms of the Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike protein and several adjuvants in an effort to identify a highly potent Coronavirus disease 2019 (COVID-19) vaccine candidate. eVLPs expressing a modified prefusion form of SARS-CoV-2 spike protein were selected as they induced high antibody binding titers and neutralizing activity after a single injection in mice. Formulation of SARS-CoV-2 S eVLPs with aluminum phosphate resulted in balanced induction of IgG2 and IgG1 isotypes and antibody binding and neutralization titers were undiminished for more than 3 months after a single immunization. Read More

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Humoral immune responses during SARS-CoV-2 mRNA vaccine administration in seropositive and seronegative individuals.

BMC Med 2021 Jul 26;19(1):169. Epub 2021 Jul 26.

Genomic Medicine Center, Children's Mercy Research Institute, Children's Mercy Kansas City, Kansas City, MO, 64108, USA.

Background: The global pandemic of coronavirus disease 2019 (COVID-19) is caused by infection with the SARS-CoV-2 virus. Currently, there are three approved vaccines against SARS-CoV-2 in the USA, including two based on messenger RNA (mRNA) technology that has demonstrated high vaccine efficacy. We sought to characterize humoral immune responses, at high resolution, during immunization with the BNT162b2 (Pfizer-BioNTech) vaccine in individuals with or without prior history of natural SARS-CoV-2 infection. Read More

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Evaluation of a multiplexed coronavirus antigen array for detection of SARS-CoV-2 specific IgG in COVID-19 convalescent plasma.

J Immunol Methods 2021 Jul 22:113104. Epub 2021 Jul 22.

Department of Pediatrics, University of Colorado School of Medicine, USA; Children's Hospital, 13123 East 16(th) Avenue, Aurora, CO 80045, USA. Electronic address:

Mitigation of the COVID-19 pandemic requires an understanding of the antibody response to SARS-CoV-2. However, throughout the development of SARS-CoV-2 IgG antibody assays during the past year, cross-reactivity to other coronaviruses remained a question. To address these issues, we evaluated IgG in COVID-19 convalescent plasma samples for reactivity against three SARS-CoV-2 antigens including full-length spike, receptor binding domain, and the proximal extracellular fusion domain, and spike antigens from other coronaviruses (SARS-CoV, MERS-CoV, hCoV-HKU1, hCoV-OC43, hCoV-229E and hCoV-NL63) using the VaxArray Coronavirus SeroAssay which is a multiplexed antigen assay developed by InDevR Inc. Read More

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Durable antibody response one year after hospitalization for COVID-19: A longitudinal cohort study.

J Autoimmun 2021 Jul 20;123:102703. Epub 2021 Jul 20.

Infectious Diseases Unit, Hospital General Universitario de Elche, Alicante, Spain; Clinical Medicine Department, Universidad Miguel Hernández, Alicante, Spain. Electronic address:

Objectives: Durability of the humoral immune response to SARS-CoV-2 has yet to be defined. We longitudinally evaluated during a 12-month period the antibody responses to SARS-CoV-2, and analysed predictors of antibody titres decline and seroreversion.

Methods: Prospective study conducted in a cohort of patients hospitalized for microbiologically-confirmed COVID-19. Read More

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Neutralizing antibodies against SARS-CoV-2 variants induced by natural infection or vaccination: a systematic review and pooled meta-analysis.

Clin Infect Dis 2021 Jul 24. Epub 2021 Jul 24.

School of Public Health, Fudan University, Key Laboratory of Public Health Safety, Ministry of Education, Shanghai, China.

Recently emerged SARS-CoV-2 variants may pose a threat to immunity. A systematic landscape of neutralizing antibodies against emerging variants is needed. We systematically searched for studies that evaluated neutralizing antibodies titers induced by previous infection or vaccination against SARS-CoV-2 variants and collected individual data. Read More

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SARS-CoV-2 Neutralizing Antibody Responses towards Full-Length Spike Protein and the Receptor-Binding Domain.

J Immunol 2021 Jul 23. Epub 2021 Jul 23.

Copenhagen University Hospital, Copenhagen, Denmark.

Tools to monitor SARS-CoV-2 transmission and immune responses are needed. We present a neutralization ELISA to determine the levels of Ab-mediated virus neutralization and a preclinical model of focused immunization strategy. The ELISA is strongly correlated with the elaborate plaque reduction neutralization test ( = 0. Read More

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Effects of treatment of COVID-19 with convalescent plasma in 25 B-cell depleted patients.

Clin Infect Dis 2021 Jul 22. Epub 2021 Jul 22.

Department of Internal Medicine, Section of Infectious Diseases and department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.

25 B-cell depleted patients (24 following anti-CD19/20 therapy) diagnosed with COVID-19, had been symptomatic for a median of 26 days but remained antibody negative. All were treated with convalescent plasma with high neutralizing antibody titers. 21 (84%) recovered, indicating the potential therapeutic effects of this therapy in this particular population. Read More

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A Phase 1 study of the long-acting anti-IL-5 monoclonal antibody GSK3511294 in patients with asthma.

Br J Clin Pharmacol 2021 Jul 22. Epub 2021 Jul 22.

Affiliation at time of study: Clinical Pharmacology Modelling & Simulation, GSK, Brentford, Middlesex, UK.

Aims: GSK3511294 is a humanized anti-interleukin (IL)-5 monoclonal antibody (mAb) engineered for extended half-life and improved IL-5 affinity versus other anti-IL-5 mAbs. This study examined its safety, tolerability, pharmacokinetics (PK) and effect on blood eosinophil counts.

Methods: This was a double-blind, parallel-group, single-ascending-dose, multicenter, Phase 1 study (205722;NCT03287310) in patients with asthma and a blood eosinophil count ≥200 cells μL . Read More

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Dynamics of the Magnitude, Breadth and Depth of the Antibody Response at Epitope Level Following Dengue Infection.

Front Immunol 2021 5;12:686691. Epub 2021 Jul 5.

Department of Biomedical Sciences, Unit of Virology, Institute of Tropical Medicine, Antwerp, Belgium.

Dengue is a major public health problem in tropical and sub-tropical regions worldwide. Since the Zika epidemic and the increased co-circulation of other arboviruses, the serology-based diagnosis of dengue has become more problematic due to the high antigenic resemblance, especially among the flavivirus family. Therefore, a more comprehensive understanding of the diversity, specificity and temporal evolution of the antibody response following dengue infection is needed. Read More

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Novel methodology comparing two assay formats for the assessment of immunogenicity from clinical trial samples.

Bioanalysis 2021 Jul 22. Epub 2021 Jul 22.

Eli Lilly & Company, Indianapolis, IN 46285, USA.

We present a novel methodology to compare results between distinct immunogenicity assays, performed by two laboratories, for the same biotherapeutic. Human serum pools from clinical trials were generated to provide representative immunogenicity titers. Pools were evaluated at two laboratories in a blinded fashion to assess the effect of assay format and laboratory change on clinical interpretation of immunogenicity results. Read More

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Pore-forming alpha-hemolysin efficiently improves the immunogenicity and protective efficacy of protein antigens.

PLoS Pathog 2021 Jul 21;17(7):e1009752. Epub 2021 Jul 21.

National Engineering Research Center of Immunological Products & Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, PR China.

Highly immunogenic exotoxins are used as carrier proteins because they efficiently improve the immunogenicity of polysaccharides. However, their efficiency with protein antigens remains unclear. In the current study, the candidate antigen PA0833 from Pseudomonas aeruginosa was fused to the α-hemolysin mutant HlaH35A from Staphylococcus aureus to form a HlaH35A-PA0833 fusion protein (HPF). Read More

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Evaluation of cell-based and surrogate SARS-CoV-2 neutralization assays.

J Clin Microbiol 2021 Jul 21:JCM0052721. Epub 2021 Jul 21.

Vaccine and Infectious Diseases Division, Fred Hutch Cancer Research Center, Seattle WA.

Determinants of protective immunity against SARS-CoV-2 infection require the development of well-standardized, reproducible antibody assays. This need has led to the emergence of a variety of neutralization assays. Head-to-head evaluation of different SARS-CoV-2 neutralization platforms could facilitate comparisons across studies and laboratories. Read More

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Preventing Pyruvate Kinase Muscle (PKM) Expression in Chinese Hamster Ovary Cells Curbs Lactogenic Behavior by Altering Glycolysis, Gating Pyruvate Generation, and Increasing Pyruvate Flux into the TCA Cycle.

Biotechnol Prog 2021 Jul 20. Epub 2021 Jul 20.

Cell Culture and Bioprocess Operations Department, Genentech Inc., South San Francisco, CA.

Deletion of the pyruvate kinase muscle (PKM) gene, which is involved in conversion of phosphoenolpyruvate to pyruvate, has been shown to curb lactogenic behavior in Chinese hamster ovary (CHO) cells. This study describes generation of pyruvate kinase muscle isoforms 1&2 knockout (PKM-KO) and pyruvate kinase muscle isoform-1 knockout (PKM1-KO) CHO host cells to understand metabolic shifts that reduce lactate secretion in these cells. Glucose and amino acids uptake levels in wild type (WT), PKM-KO, and PKM1-KO stable cell lines, expressing two different antibodies, were analyzed in 14-day fed batch production assays using different vessels. Read More

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Diagnostic challenges in patients with temporal lobe seizures and features of autoimmune limbic encephalitis.

Eur J Neurol 2021 Jul 20. Epub 2021 Jul 20.

Department of Neurology, University Hospital Knappschaftskrankenhaus Bochum, Bochum, Germany.

Background: Consensus criteria for autoimmune limbic encephalitis (ALE) allow for a diagnosis even without neural antibodies (Abs), but it remains unclear which clinical features should prompt neural Ab screening in temporal lobe epilepsy patients.

Methods: We identified 47 patients from a tertiary epilepsy center with mediotemporal lobe seizures and additional features suggestive of limbic involvement, including either memory deficits, psychiatric symptoms, mediotemporal MRI hyperintensities or inflammatory CSF. Neuronal Ab testing was carried out at two independent reference laboratories (Bielefeld-Bethel, Germany, and Barcelona, Spain). Read More

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BCL6 BTB-specific inhibitor reversely represses T Cell activation, Tfh cells differentiation and germinal center reaction in vivo.

Eur J Immunol 2021 Jul 21. Epub 2021 Jul 21.

The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA.

Inhibition of the BCL6 BTB domain results in killing Diffuse Large B-cell Lymphoma (DLBL) cells, reducing the T-cell dependent germinal center (GC) reaction in mice, and reversing GC hyperplasia in nonhuman primates. The available BCL6 BTB-specific inhibitors are poorly water soluble thus limiting their absorption in vivo and our understanding of therapeutic strategy targeting GC. We synthesized a prodrug (AP-4-287) from a potent BCL6 BTB inhibitor (FX1) with improved aqueous solubility and pharmacokinetics (PK) in mice. Read More

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