29,911 results match your criteria neutralization test

Convalescent plasma therapy in patients with moderate-to-severe COVID-19: A study from Indonesia for clinical research in low- and middle-income countries.

EClinicalMedicine 2021 Jun 4:100931. Epub 2021 Jun 4.

Eijkman Institute for Molecular Biology, Jl. Diponegoro 69, Jakarta 10430, Indonesia.

Background: We explored the outcome of convalescent plasma (CP) treatment in patients with moderate and severe coronavirus disease 2019 (COVID-19) and investigated variables for the design of further trials in Indonesia.

Methods: Hospitalised patients with moderate ( = 5) and severe ( = 5) COVID-19 were recruited and transfused with CP from donors who recovered from mild ( = 5), moderate ( = 5), or severe ( = 1) COVID-19. Neutralising antibodies (NAbs) to the virus were measured at the end of the study using a surrogate virus neutralisation test as an alternative to the plaque reduction assay. Read More

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Function is more reliable than quantity to follow up the humoral response to the Receptor Binding Domain of SARS- CoV-2 Spike protein after natural infection or COVID-19 vaccination.

medRxiv 2021 Jun 3. Epub 2021 Jun 3.

On this work we report that despite of a decline in the total anti-Spike antibodies the neutralizing antibodies remains at a similar level for an average of 98 days in a longitudinal cohort of 59 Hispanic/Latino exposed to SARS-CoV-2. We are also reporting that the percentage of neutralization correlates with the IgG titers and that in the first collected samples, IgG1 was the predominant isotype (62.71%), followed by IgG4 (15. Read More

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The application of laboratory-based analytical tools and techniques for the quality assessment and improvement of commercial antivenoms used in the treatment of snakebite envenomation.

Drug Test Anal 2021 Jun 5. Epub 2021 Jun 5.

Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, 784028, Assam, India.

Snakebite envenomation is a public health problem of high impact, particularly for the developing world. Antivenom, that contains whole or protease-digested immunoglobulin G, purified from the plasma of hyper-immunized animals (mainly horses), is the mainstay for the treatment of snakebite envenomation. The success of antivenom therapy depends upon its ability to abrogate or reduce the local and systemic toxicity of envenomation. Read More

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Marked increase in avidity of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) antibodies 7-8 months after infection is not diminished in old age.

J Infect Dis 2021 Jun 4. Epub 2021 Jun 4.

Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria.

The kinetics of IgG avidity maturation during severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection obtained from 217 participants of the Ischgl cohort, Austria, was studied 0.5-1.5 (baseline) and 7-8 months (follow up) after infection. Read More

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IMMUNO-COV v2.0: Development and Validation of a High-Throughput Clinical Assay for Measuring SARS-CoV-2-Neutralizing Antibody Titers.

mSphere 2021 Jun 2:e0017021. Epub 2021 Jun 2.

Imanis Life Sciences, Rochester, Minnesota, USA.

Neutralizing antibodies are key determinants of protection from future infection, yet well-validated high-throughput assays for measuring titers of SARS-CoV-2-neutralizing antibodies are not generally available. Here, we describe the development and validation of IMMUNO-COV v2.0, a scalable surrogate virus assay, which titrates antibodies that block infection of Vero-ACE2 cells by a luciferase-encoding vesicular stomatitis virus displaying SARS-CoV-2 spike glycoproteins (VSV-SARS2-Fluc). Read More

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Evidence of neutralizing antibodies against SARS-CoV-2 in domestic cats living with owners with a history of COVID-19 in Lima - Peru.

bioRxiv 2021 May 26. Epub 2021 May 26.

SARS-CoV-2 can infect a variety of wild and domestic animals worldwide. Of these, domestic cats are highly susceptible species and potential viral reservoirs. As such, it is important to investigate disease exposure in areas with active community transmission and high disease prevalence. Read More

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Kinetics of Neutralizing Antibodies of COVID-19 Patients Tested Using Clinical D614G, B.1.1.7, and B 1.351 Isolates in Microneutralization Assays.

Viruses 2021 05 26;13(6). Epub 2021 May 26.

Department of Virology, Faculty of Medicine, University of Helsinki, 00290 Helsinki, Finland.

Increasing evidence suggests that some newly emerged SARS-CoV-2 variants of concern (VoCs) resist neutralization by antibodies elicited by the early-pandemic wild-type virus. We applied neutralization tests to paired recoveree sera ( = 38) using clinical isolates representing the first wave (D614G), VoC1, and VoC2 lineages (B.1. Read More

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Evidence of West Nile Virus Circulation in Lebanon.

Viruses 2021 May 26;13(6). Epub 2021 May 26.

Laboratory of Immunology and Vector-Borne Diseases, Faculty of Public Health, Lebanese University, Fanar 6573/14, Lebanon.

West Nile virus (WNV) has never been reported from Lebanon. Yet, this country is located on the flyway of migratory birds in the Middle East region. Serological screening was conducted to assess the potential circulation of this virus. Read More

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Effectiveness of the SA 14-14-2 Live-Attenuated Japanese Encephalitis Vaccine in Myanmar.

Vaccines (Basel) 2021 May 31;9(6). Epub 2021 May 31.

Department of Virology, Institute of Tropical Medicine and Leading Program, Nagasaki University, Nagasaki 852-8523, Japan.

Myanmar is an endemic country for the Japanese encephalitis virus (JEV), and the SA-14-14-2 live-attenuated JEV vaccine was first introduced as a catch-up vaccination campaign in 2017. To determine the effectiveness of vaccination by means of neutralizing antibody titers against JEV, a cross-sectional descriptive study was conducted among five to 15-year-old monastic school children in Mandalay, Myanmar. A total of 198 students who had received vaccines were recruited, and single-time investigation of anti-JEV IgG and neutralizing antibodies against wild-type JEV were determined using anti-JEV IgG ELISA and plaque reduction neutralization tests (PRNT). Read More

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A Virus-Like Particle-Based Vaccine Candidate against the Tick-Borne Powassan Virus Induces Neutralizing Antibodies in a Mouse Model.

Pathogens 2021 May 31;10(6). Epub 2021 May 31.

American Type Culture Collection (ATCC®), ATCC Federal Solutions, 10801 University Boulevard, Manassas, VA 20110, USA.

Powassan virus (POWV) is a tick-borne flavivirus circulating in North America and the Russian Far East that can cause severe neuroinvasive diseases, including encephalitis, meningitis, and meningoencephalitis. The reported neuroinvasive case fatality is about 10%, and approximately 50% of the survivors from the neuroinfection exhibit long-lasting or permanent neurological sequelae. Currently, treatment of POWV infection is supportive, and no FDA-approved vaccines or specific therapeutics are available. Read More

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Antimicrobial and Anti-Biofilm Peptide Octominin for Controlling Multidrug-Resistant .

Int J Mol Sci 2021 May 19;22(10). Epub 2021 May 19.

National Marine Biodiversity Institute of Korea (MABIK), 75, Jangsan-ro 101 beon-gil, Janghang-eup, Seochun-gun, Chungchungnam-do 33662, Korea.

is a serious nosocomial pathogen with multiple drug resistance (MDR), the control of which has become challenging due to the currently used antibiotics. Our main objective in this study is to determine the antibacterial and antibiofilm activities of the antimicrobial peptide, Octominin, against MDR and derive its possible modes of actions. Octominin showed significant bactericidal effects at a low minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of 5 and 10 µg/mL, respectively. Read More

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Utility of Different Surrogate Enzyme-Linked Immunosorbent Assays (sELISAs) for Detection of SARS-CoV-2 Neutralizing Antibodies.

J Clin Med 2021 May 14;10(10). Epub 2021 May 14.

Institute for Medical Virology, University Hospital, Goethe University Frankfurt am Main, 60596 Frankfurt, Germany.

The plaque reduction neutralization test (PRNT) is a preferred method for the detection of functional, SARS-CoV-2 specific neutralizing antibodies from serum samples. Alternatively, surrogate enzyme-linked immunosorbent assays (ELISAs) using ACE2 as the target structure for the detection of neutralization-competent antibodies have been developed. They are capable of high throughput, have a short turnaround time, and can be performed under standard laboratory safety conditions. Read More

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Bacteriostatic Behavior of PLA-BaTiO Composite Fibers Synthesized by Centrifugal Spinning and Subjected to Aging Test.

Molecules 2021 May 14;26(10). Epub 2021 May 14.

Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto 606-8585, Japan.

The present work investigated the effect of Polylactic acid (PLA) fibers produced by centrifugal spinning with incorporated BaTiO particles to improve their bacteriostatic behavior. The PLA matrix and three composites, presenting three different amounts of fillers, were subjected to UV/O treatment monitoring the possible modifications that occurred over time. The morphological and physical properties of the surfaces were characterized by different microscopic techniques, contact angle, and surface potential measurements. Read More

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Serological Evidence of Human Orthohantavirus Infections in Barbados, 2008 to 2016.

Pathogens 2021 May 8;10(5). Epub 2021 May 8.

Best-dos Santos Public Health Laboratory, Enmore #6, Lower Collymore Rock, St. Michael BB11155, Barbados.

Background: Hantavirus pulmonary syndrome (HPS) is well-known in South and North America; however, not enough data exist for the Caribbean. The first report of clinical orthohantavirus infection was obtained in Barbados, but no other evidence of clinical orthohantavirus infections among adults in the Caribbean has been documented.

Methods: Using enzyme linked immunosorbent assay (ELISA) tests followed by confirmatory testing with immunofluorescent assays (IFA), immunochromatographic (ICG) tests, and pseudotype focus reduction neutralization tests (pFRNT), we retrospectively and prospectively detected orthohantavirus-specific antibodies among patients with febrile illness in Barbados. Read More

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Scalable, Micro-Neutralization Assay for Assessment of SARS-CoV-2 (COVID-19) Virus-Neutralizing Antibodies in Human Clinical Samples.

Viruses 2021 05 12;13(5). Epub 2021 May 12.

Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA.

As the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic expanded, it was clear that effective testing for the presence of neutralizing antibodies in the blood of convalescent patients would be critical for development of plasma-based therapeutic approaches. To address the need for a high-quality neutralization assay against SARS-CoV-2, a previously established fluorescence reduction neutralization assay (FRNA) against Middle East respiratory syndrome coronavirus (MERS-CoV) was modified and optimized. The SARS-CoV-2 FRNA provides a quantitative assessment of a large number of infected cells through use of a high-content imaging system. Read More

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Prevalence of Neutralizing Antibodies to Canine Distemper Virus and Response to Vaccination in Client-Owned Adult Healthy Dogs.

Viruses 2021 May 20;13(5). Epub 2021 May 20.

Clinic of Small Animal Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany.

Re-vaccinations against canine distemper virus (CDV) are commonly performed in 3-year intervals. The study's aims were to determine anti-CDV antibodies in healthy adult dogs within 28 days of vaccination against CDV, and to evaluate factors associated with the presence of pre-vaccination antibodies and with the antibody response to vaccination. Ninety-seven dogs, not vaccinated within 1 year before enrollment, were vaccinated with a modified live CDV vaccine. Read More

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Investigating the Presence of SARS CoV-2 in Free-Living and Captive Animals.

Pathogens 2021 May 21;10(6). Epub 2021 May 21.

Virology Department, Croatian Veterinary Institute, Savska Cesta 143, 10000 Zagreb, Croatia.

Due to SARS CoV-2 recombination rates, number of infected people and recent reports of environmental contamination, the possibility of SARS CoV-2 transmission to animals can be expected. We tested samples of dominant free-living and captive wildlife species in Croatia for the presence of anti-SARS CoV-2 antibodies and viral RNA. In total, from June 2020 until February 2021, we tested blood, muscle extract and fecal samples of 422 free-living wild boars (), red foxes () and jackals (); blood and cloacal swabs of 111 yellow-legged gulls () and fecal samples of 32 zoo animals. Read More

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Low Seroprevalence of Aichi Virus Infection in Taiwan.

Pathogens 2021 May 3;10(5). Epub 2021 May 3.

Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei 11490, Taiwan.

Aichi virus (AiV) belongs to the genus of the family Picornaviridae; it is a single-stranded positive-sense RNA virus without an envelope. AiV causes acute gastroenteritis, abdominal pain, nausea, vomiting, and fever. Low incidence and high seroprevalence of AiV infections have been reported in several regions of the world; however, little was known on the prevalence of AiV infections in Taiwan. Read More

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A Reliable Indirect ELISA Protocol for Detection of Human Antibodies Directed to SARS-CoV-2 NP Protein.

Diagnostics (Basel) 2021 May 2;11(5). Epub 2021 May 2.

Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 128442, Jeddah 21362, Saudi Arabia.

A few months ago, the availability of a reliable and cost-effective testing capacity for COVID-19 was a concern for many countries. With the emergence and circulation of new SARS-CoV-2 variants, another layer of challenge can be added for COVID-19 testing at both molecular and serological levels. This is particularly important for the available tests principally designed to target the S gene/protein where multiple mutations have been reported. Read More

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Antibody Responses One Year after Mild SARS-CoV-2 Infection.

J Korean Med Sci 2021 May 31;36(21):e157. Epub 2021 May 31.

Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.

Understanding the long-term kinetics of antibodies in coronavirus disease 2019 (COVID-19) is essential in interpreting serosurvey data. We investigated the antibody response one year after infection in 52 mildly symptomatic patients with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, using three commercial immunoassays and a surrogate virus neutralization test (sVNT) kit. Anti-N pan-immunoglobulin (Ig), anti-S IgG, and anti-S1 IgG were detected in 43 (82. Read More

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Immune response to SARS-CoV-2 variants of concern in vaccinated individuals.

Nat Commun 2021 05 25;12(1):3109. Epub 2021 May 25.

NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany.

SARS-CoV-2 is evolving with mutations in the receptor binding domain (RBD) being of particular concern. It is important to know how much cross-protection is offered between strains following vaccination or infection. Here, we obtain serum and saliva samples from groups of vaccinated (Pfizer BNT-162b2), infected and uninfected individuals and characterize the antibody response to RBD mutant strains. Read More

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A field study evaluating the humoral immune response in Mongolian sheep vaccinated against sheeppox virus.

Transbound Emerg Dis 2021 May 25. Epub 2021 May 25.

The Pirbright Institute, Ash Road, Pirbright, GU24 0NF, UK.

Sheeppox is a transboundary disease of small ruminants caused by infection with the capripoxvirus sheeppox virus (SPPV). Sheeppox is found in Africa, the Middle East and Asia and is characterised by fever, multifocal cutaneous raised lesions, and death. Vaccination with live attenuated capripoxvirus (CPPV) strains is an effective and widely used strategy to contol sheeppox outbreaks, however there are few reports of post-vaccination field surveillance studies. Read More

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Acid rain leaching behavior of Zn-contaminated soils solidified/stabilized using cement-soda residue.

Chemosphere 2021 May 17;281:130916. Epub 2021 May 17.

School of Resource and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China.

Cement-soda residue (CSR) has been proven to be an effective binder for treating heavy metal-contaminated soils, and the durability is its most important characteristic. In this study, the effects of acid rain (AR) on the leaching behavior of CSR-solidified/stabilized, zinc-contaminated soils were investigated using flexible-wall soil column leaching tests. After leaching, some parameters were determined such as the unconfined compressive strength (UCS) and permeability coefficient of the samples, the concentrations of Zn and Ca in the filtrate. Read More

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A Serosurvey of Tick-Borne Encephalitis Virus in Sweden: Different Populations and Geographical Locations.

Vector Borne Zoonotic Dis 2021 May 21. Epub 2021 May 21.

Department of Laboratory Medicine and Lund University, Skåne University Hospital, Lund, Sweden.

New risk areas for tick-borne encephalitis (TBE) are emerging and the spread of disease and vaccine coverage is unclear in Sweden. We wanted to study the prevalence and levels of TBE-virus (TBEV) antibodies in southern Sweden, and to investigate whether there were individuals with undiagnosed TBE. Two cohorts of sera were collected: One group of anonymous individuals in rural areas (AIRA) in Skåne and one group of volunteers who often got tick-bites (tick-bitten individuals [TBI]). Read More

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Comparison of hemagglutination inhibition and hemagglutinin pseudovirus neutralization titres in relation to protection against influenza in a mouse model.

Lett Appl Microbiol 2021 May 24. Epub 2021 May 24.

Office of Biostatistics and Epidemiology, FDA Center for Biologics Evaluation and Research, Silver Spring, MD, USA.

The hemagglutination inhibition (HI) test has long been used as a standard measure of antibody response for inactivated influenza vaccines. However, the HI test has limitations, such as insensitivity when using some H3N2 virus strains and failure to detect neutralizing antibodies that target regions distant from the receptor binding site. We therefore examined a hemagglutinin pseudovirus neutralization (PVN) test as a possible supplement or alternative to the HI test. Read More

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Genetic Characterization of Feline Parvovirus Isolate Fe-P2 in Korean Cat and Serological Evidence on Its Infection in Wild Leopard Cat and Asian Badger.

Front Vet Sci 2021 7;8:650866. Epub 2021 May 7.

Department of Microbiology, College of Natural Science, Chungbuk National University, Cheongju, South Korea.

Feline parvovirus (FPV) is a small, non-enveloped, single-stranded DNA virus that infects cats. We recently isolated a feline parvovirus Fe-P2 strain from a dead stray cat in Iksan, 2017. Its partial genomic sequence (4,643 bases) was obtained, and phylogenetic analysis based on the VP2 nucleotide sequence showed that the FPV Fe-P2 strain was closely related to the FPV isolate Gigucheon in cat, 2017 (MN400978). Read More

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Influence of adjuvants on the amount, specificity and functional activity of antibody response to human influenza vaccine in mice.

Mol Immunol 2021 Jul 20;135:398-407. Epub 2021 May 20.

Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Av. Universidad 3000, CP 04510, Ciudad de México, Mexico. Electronic address:

It's been almost a century since immunologists started using adjuvants as tools to develop more effective vaccines. Despite the rising number of adjuvanted vaccines in the last decades, we still lack knowledge of the adjuvants' effects on antibody response. This study was aimed to test the effect of immunizing mice with the human Inactivated Influenza vaccine (IIV), either alone or combined with different widely used adjuvants on the specific antibody response induced. Read More

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Safety and immunogenicity of a purified inactivated Zika virus vaccine candidate in healthy adults: an observer-blind, randomised, phase 1 trial.

Lancet Infect Dis 2021 May 18. Epub 2021 May 18.

Clinical Development, Takeda Pharmaceuticals International, Zurich, Switzerland.

Background: Zika virus, a flavivirus transmitted by Aedes aegypti and Aedes albopictus mosquitoes, is associated with cases of congenital malformations and neurological complications. Absence of specific treatment makes a prophylactic Zika virus vaccine an unmet medical need. We assessed safety and immunogenicity of three doses of a purified, inactivated, Zika virus vaccine candidate in healthy flavivirus-naive and flavivirus-primed adults. Read More

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Epigallocatechin Gallate Inhibits the Uridylate-Specific Endoribonuclease Nsp15 and Efficiently Neutralizes the SARS-CoV-2 Strain.

J Agric Food Chem 2021 Jun 21;69(21):5948-5954. Epub 2021 May 21.

Department of Agricultural Biotechnology, Center for Food and Bioconvergence, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.

SARS-CoV-2, the coronavirus strain that initiated the COVID-19 pandemic, and its subsequent variants present challenges to vaccine development and treatment. As the coronavirus evades the host innate immune response at the initial stage of infection, the disease can have a long nonsymptomatic period. The uridylate-specific endoribonuclease Nsp15 processes the viral genome for replication and cleaves the polyU sequence in the viral RNA to interfere with the host immune system. Read More

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Baseline Asymptomatic Malaria Infection and Immunogenicity of rVSVΔG-ZEBOV-GP Vaccine: The Sierra Leone Trial to Introduce a Vaccine Against Ebola (STRIVE).

J Infect Dis 2021 May 20. Epub 2021 May 20.

Centers for Disease Control and Prevention, Atlanta, GA, 30329-4027 USA.

Background: The effect of malaria infection on rVSVΔG-ZEBOV-GP (ERVEBO®) immunogenicity is unknown.

Methods: The Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE) vaccinated 7998 asymptomatic adults with rVSVΔG-ZEBOV-GP during the 2014-6 Ebola epidemic. In STRIVE's immunogenicity sub-study, participants provided blood samples at baseline, 1, 6, and 9-12 months. Read More

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