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Methods in Molecular Biology (Clifton,... 2020The hemagglutination inhibition (HI) assay for influenza A virus has been used since the 1940s. The assay may be utilized to detect or quantify antibodies to influenza A...
The hemagglutination inhibition (HI) assay for influenza A virus has been used since the 1940s. The assay may be utilized to detect or quantify antibodies to influenza A viruses and can be used to characterize differences in antigenic reactivity between influenza isolates. In addition, data from HI assays are routinely used for antigenic cartography, influenza virus surveillance, epidemiology, and vaccine-seed strain selection. For antibody quantification, the HI assay is a fast and inexpensive method; other than a source of red blood cells, no expensive or unusual lab equipment is needed, and results can be obtained within a few hours. Historically, the HI assay has also served as a primary method of subtype identification and is still used widely. However, as gene sequencing technology has evolved to be cheaper and faster, it is replacing the HI assay for this purpose.
Topics: Animals; Antibodies, Viral; Antibody Specificity; Antigens, Viral; Chickens; Erythrocytes; Hemagglutination Inhibition Tests; Immune Sera
PubMed: 32170677
DOI: 10.1007/978-1-0716-0346-8_2 -
PloS One 2016Immunity to human influenza A virus (IAV) infection is only partially understood. Broadly non-neutralizing antibodies may assist in reducing disease but have not been...
BACKGROUND
Immunity to human influenza A virus (IAV) infection is only partially understood. Broadly non-neutralizing antibodies may assist in reducing disease but have not been well characterized.
METHODS
We measured internalization of opsonized, influenza protein-coated fluorescent beads and live IAV into a monocytic cell line to study antibody-dependent phagocytosis (ADP) against multiple influenza hemagglutinin (HA) subtypes. We analyzed influenza HA-specific ADP in healthy human donors, in preparations of intravenous immunoglobulin (IVIG), and following IAV infection of humans and macaques.
RESULTS
We found that both sera from healthy adults and IVIG preparations had broad ADP to multiple seasonal HA proteins and weak cross-reactive ADP to non-circulating HA proteins. The ADP in experimentally influenza-infected macaque plasma and naturally influenza-infected human sera mediated phagocytosis of both homologous and heterologous IAVs. Further, the IAV phagocytosed in an antibody-mediated manner had reduced infectivity in vitro.
CONCLUSION
We conclude that IAV infections in humans and macaques leads to the development of influenza-specific ADP that can clear IAV infection in vitro. Repeated exposure of humans to multiple IAV infections likely leads to the development of ADP that is cross-reactive to strains not previously encountered. Further analyses of the protective capacity of broadly reactive influenza-specific ADP is warranted.
Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; Cell Line; Cross Protection; Cross Reactions; Fluorescent Dyes; Hemagglutination Inhibition Tests; Hemagglutinin Glycoproteins, Influenza Virus; Humans; Immobilized Proteins; Immune Sera; Immunity, Humoral; Immunoglobulins, Intravenous; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Macaca nemestrina; Microspheres; Monocytes; Orthomyxoviridae Infections; Phagocytosis
PubMed: 27124730
DOI: 10.1371/journal.pone.0154461 -
Methods in Molecular Biology (Clifton,... 2015Polyclonal antibodies are relatively easy to produce and may supplement monoclonal antibodies for some applications or even have some advantages. The choice of species...
Polyclonal antibodies are relatively easy to produce and may supplement monoclonal antibodies for some applications or even have some advantages. The choice of species for production of (peptide) antisera is based on practical considerations, including availability of immunogen (vaccine) and animals. Two major factors govern the production of antisera: the nature of adaptive immune responses, which take place over days/weeks and ethical guidelines for animal welfare. Here, simple procedures for immunization of mice, rabbits, sheep, goats, pigs, horses, and chickens are presented.
Topics: Animals; Antibody Formation; Antigens; Chickens; Horses; Immune Sera; Immunization; Immunoassay; Mice; Peptides; Rabbits; Sheep; Swine
PubMed: 26424267
DOI: 10.1007/978-1-4939-2999-3_11 -
Cold Spring Harbor Protocols May 2017This assay facilitates the immunometric determination of assay-associated reagents including the capture and detection antibodies as well as the analyte (i.e., antigen...
This assay facilitates the immunometric determination of assay-associated reagents including the capture and detection antibodies as well as the analyte (i.e., antigen or antibody). It can precede the development of a sandwich enzyme-linked immunosorbent assay (ELISA) in which optimal antibody concentrations are applied for the quantitative measurement of the antigen. This protocol describes the materials and equipment required for the measurement of chromogenic substrate development; however, it can be adapted for use with chemiluminescent- and fluorescent-labeled reporters.
Topics: Antibodies; Antigens; Enzyme-Linked Immunosorbent Assay; Immune Sera; Indicators and Reagents
PubMed: 28461658
DOI: 10.1101/pdb.prot093708 -
Immunohematology Sep 2016Reagent-dependent reactivity can be described as agglutination of red blood cells (RBCs) in serologic testing that is not related to the interaction of RBC antigens and... (Review)
Review
Reagent-dependent reactivity can be described as agglutination of red blood cells (RBCs) in serologic testing that is not related to the interaction of RBC antigens and antibodies that the test system is intended to detect. In other words, reagent-dependent reactivity results in false-positive agglutination reactions in serologic testing. These false-positive reactions can cause confusion in antigen typing and RBC antibody detection and identification procedures, and may result in delays in patient transfusion. It is imperative that reagent-dependent reactivity is recognized and resolved during the investigation of ABO discrepancies, positive RBC antibody screens and antibody identification panels, and crossmatch reactivity.
Topics: Agglutination Tests; Antibody Specificity; Artifacts; Automation; Blood Grouping and Crossmatching; Erythrocytes; False Positive Reactions; High-Throughput Screening Assays; Humans; Immune Sera; Indicators and Reagents; Isoantibodies; Preservatives, Pharmaceutical; Product Labeling
PubMed: 27834481
DOI: No ID Found -
The Keio Journal of Medicine Dec 2017Blood serum from immunized humans or animals (e.g., horses) contains relevant antibodies and has been used as serum therapy to treat many diseases or envenomation... (Review)
Review
Blood serum from immunized humans or animals (e.g., horses) contains relevant antibodies and has been used as serum therapy to treat many diseases or envenomation events. The effectiveness of blood serum was initially discovered in 1890 when Kitasato and von Behring observed the effectiveness of this type of therapy against diphtheria and tetanus. Serum therapies played an important role in the advancement of modern medicine prior to the development of penicillin and steroids. At present, several types of serum therapy remain in clinical use. However, some physicians have a limited understanding of the nature and the benefits of serum therapy and the factors that require particular attention. In this review, we set out to clarify the benefits, cautions, and potential applications of serum therapy in the context of conditions such as gas gangrene, diphtheria, botulism, and tetanus and bites from three snake species (mamushi, habu, and yamakagashi) and the redback spider. It is hoped that this review will help clinicians to learn about clinical serum therapies and become familiar with their applications.
Topics: Animals; Antitoxins; Antivenins; Botulism; Diphtheria; Gas Gangrene; Horses; Humans; Immune Sera; Immunization, Passive; Snake Bites; Spider Bites; Tetanus
PubMed: 28450682
DOI: 10.2302/kjm.2016-0017-IR -
Archives of Virology Aug 2022Earlier studies have shown that Tembusu virus (TMUV) can elicit high levels of neutralizing antibodies, but the ability of antibodies to protect against TMUV-associated...
Earlier studies have shown that Tembusu virus (TMUV) can elicit high levels of neutralizing antibodies, but the ability of antibodies to protect against TMUV-associated disease and to inhibit replication of TMUV in vivo remains to be investigated. Here, we tested the prophylactic efficacy of TMUV immune serum directly using a 2-day-old Pekin duck model. Passive administration of the immune serum prior to challenge protected ducklings against morbidity and mortality, substantially reduced TMUV-caused tissue injury, and significantly decreased TMUV levels in the periphery and central nervous system. These findings demonstrate that antibodies play a dominant protective role in controlling TMUV-associated disease.
Topics: Animals; Ducks; Flavivirus; Flavivirus Infections; Immune Sera; Poultry Diseases
PubMed: 35639191
DOI: 10.1007/s00705-022-05460-4 -
Viruses Jun 2020As of June 2020, the number of people infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) continues to skyrocket, with more than 6.7 million cases...
As of June 2020, the number of people infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) continues to skyrocket, with more than 6.7 million cases worldwide. Both the World Health Organization (WHO) and United Nations (UN) has highlighted the need for better control of SARS-CoV-2 infections. However, developing novel virus-specific vaccines, monoclonal antibodies and antiviral drugs against SARS-CoV-2 can be time-consuming and costly. Convalescent sera and safe-in-man broad-spectrum antivirals (BSAAs) are readily available treatment options. Here, we developed a neutralization assay using SARS-CoV-2 strain and Vero-E6 cells. We identified the most potent sera from recovered patients for the treatment of SARS-CoV-2-infected patients. We also screened 136 safe-in-man broad-spectrum antivirals against the SARS-CoV-2 infection in Vero-E6 cells and identified nelfinavir, salinomycin, amodiaquine, obatoclax, emetine and homoharringtonine. We found that a combination of orally available virus-directed nelfinavir and host-directed amodiaquine exhibited the highest synergy. Finally, we developed a website to disseminate the knowledge on available and emerging treatments of COVID-19.
Topics: Amodiaquine; Animals; Antiviral Agents; Betacoronavirus; COVID-19; Caco-2 Cells; Cell Line, Tumor; Chlorocebus aethiops; Coronavirus Infections; Drug Therapy, Combination; Emetine; HEK293 Cells; HT29 Cells; Homoharringtonine; Humans; Immune Sera; Immunization, Passive; Indoles; Nelfinavir; Neutralization Tests; Pandemics; Pneumonia, Viral; Pyrans; Pyrroles; SARS-CoV-2; Vero Cells; COVID-19 Serotherapy
PubMed: 32545799
DOI: 10.3390/v12060642 -
Journal of Biomedical Science Jun 2023Flavivirus causes many serious public health problems worldwide. However, licensed DENV vaccine has restrictions on its use, and there is currently no approved ZIKV...
BACKGROUND
Flavivirus causes many serious public health problems worldwide. However, licensed DENV vaccine has restrictions on its use, and there is currently no approved ZIKV vaccine. Development of a potent and safe flavivirus vaccine is urgently needed. As a previous study revealed the epitope, RCPTQGE, located on the bc loop in the E protein domain II of DENV, in this study, we rationally designed and synthesized a series of peptides based on the sequence of JEV epitope RCPTTGE and DENV/ZIKV epitope RCPTQGE.
METHODS
Immune sera were generated by immunization with the peptides which were synthesized by using five copies of RCPTTGE or RCPTQGE and named as JEV-NTE and DV/ZV-NTE Immunogenicity and neutralizing abilities of JEV-NTE or DV/ZV-NTE-immune sera against flavivirus were evaluated by ELISA and neutralization tests, respectively. Protective efficacy in vivo were determined by passive transfer the immune sera into JEV-infected ICR or DENV- and ZIKV-challenged AG129 mice. In vitro and in vivo ADE assays were used to examine whether JEV-NTE or DV/ZV-NTE-immune sera would induce ADE.
RESULTS
Passive immunization with JEV-NTE-immunized sera or DV/ZV-NTE-immunized sera could increase the survival rate or prolong the survival time in JEV-challenged ICR mice and reduce the viremia levels significantly in DENV- or ZIKV-infected AG129 mice. Furthermore, neither JEV -NTE- nor DV/ZV-NTE-immune sera induced antibody-dependent enhancement (ADE) as compared with the control mAb 4G2 both in vitro and in vivo.
CONCLUSIONS
We showed for the first time that novel bc loop epitope RCPTQGE located on the amino acids 73 to 79 of DENV/ZIKV E protein could elicit cross-neutralizing antibodies and reduced the viremia level in DENV- and ZIKV-challenged AG129 mice. Our results highlighted that the bc loop epitope could be a promising target for flavivirus vaccine development.
Topics: Animals; Mice; Mice, Inbred ICR; Antibodies, Neutralizing; Viremia; Zika Virus Infection; Zika Virus; Immune Sera; Epitopes; Transcription Factors
PubMed: 37316861
DOI: 10.1186/s12929-023-00938-y -
Emerging Microbes & Infections Dec 2023Since the first human case in 2013, H7N9 avian influenza viruses (AIVs) have caused more than 1500 human infections with a mortality rate of approximately 40%. Despite...
Since the first human case in 2013, H7N9 avian influenza viruses (AIVs) have caused more than 1500 human infections with a mortality rate of approximately 40%. Despite large-scale poultry vaccination regimes across China, the H7N9 AIVs continue to persist and evolve rapidly in poultry. Recently, several strains of H7N9 AIVs have been isolated and shown the ability to escape vaccine-induced immunity. To assess the zoonotic risk of the recent H7N9 AIV isolates, we rescued viruses with hemagglutinin (HA) and neuraminidase (NA) from these H7N9 AIVs and six internal segments from PR8 virus and characterized their receptor binding, pH of fusion, thermal stability, plaque morphology and virus replication. We also assessed the cross-reactivity of the viruses with human monoclonal antibodies (mAbs) against H7N9 HA and ferret antisera against H7N9 AIV candidate vaccines. The H7N9 AIVs from the early epidemic waves had dual sialic acid receptor binding characteristics, whereas the more recent H7N9 AIVs completely lost or retained only weak human sialic acid receptor binding. Compared with the H7N9 AIVs from the first epidemic wave, the 2020/21 viruses formed larger plaques in Madin-Darby canine kidney (MDCK) cells and replicated to higher titres , demonstrating increased acid stability but reduced thermal stability. Further analysis showed that these recent H7N9 AIVs had poor cross-reactivity with the human mAbs and ferret antisera, highlighting the need to update the vaccine candidates. To conclude, the newly emerged H7N9 AIVs showed characteristics of typical AIVs, posing reduced zoonotic risk but a heightened threat for poultry.
Topics: Animals; Dogs; Humans; Influenza A Virus, H7N9 Subtype; Ferrets; Hemagglutinins; Poultry; Risk Assessment; Immune Sera; Influenza, Human; Influenza in Birds; Hemagglutinin Glycoproteins, Influenza Virus
PubMed: 36714929
DOI: 10.1080/22221751.2023.2172965