Search

Abstract As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, a series of vaccines, antibodies and drugs have been developed to combat coronavirus disease 2019 (COVID-19). High specific antibodies are powerful tool for the development of immunoassay and providing passive immunotherapy against SARS-CoV-2 and expected with large scale production. SARS-CoV-2 S1 protein was expressed in E. coli BL21 and purified by immobilized metal affinity chromatography, as antigen used to immunize hens, the specific IgY antibodies were extracted form egg yolk by PEG-6000 precipitation, and the titer of anti-S1 IgY antibody reached 1:10,000. IgY single chain variable fragment antibody (IgY-scFv) was generated by using phage display technology and the IgY-scFv showed high binding sensitivity and capacity to S1 protein of SARS-CoV-2, and the minimum detectable antigen S1 protein concentration was 6 ng/µL. The docking study showed that the multiple epitopes on the IgY-scFv interacted with multiple residues on SARS-CoV-2 S1 RBD to form hydrogen bonds. This preliminary study suggests that IgY and IgY-scFv are suitable candidates for the development of immunoassay and passive immunotherapy for COVID-19 to humans and animals.

Abstract Antibody mimetics may be used for various biomedical applications, especially those for which conventional antibodies are ineffective. In this study, we developed a smaller molecular chicken IgY mimetic peptide (IgY-peptide) based on the complementarity-determining regions (CDRs) of the anti-canine parvovirus (CPV) IgY-scFv prepared previously. The mimetic peptide showed no cross-reactivity with canine distemper virus (CDV) and canine coronavirus (CCV) and showed excellent protective properties for Crandell-Rees Feline Kidney (CRFK) cells against CPV. This study is the first attempt to develop a mimetic IgY-peptide and demonstrates the ease and feasibility in generating such a novel antibody-like functional molecule for biomedical purposes.

ABSTRACT: Egg yolk immunoglobulin (IgY) is a class of antibody that is produced in birds against pathogens. Therefore, hyperimmunization of birds can produce a specific antibody in the egg against target antigen for a wide range of applications in diagnostic, prophylactic or treatment in human and veterinary medicine which is known today as IgY technology. Until now, the number of articles, patents and clinical studies on IgY technology has increased significantly. Hence, there is a fact that scientometric studies are needed to gain a deeper understanding of the research for the commercialization of IgY technology. Until now, no scientometric research has been directed toward IgY technology. In view of this, we conducted scientometric analysis in the WoS database. A total of 1,029 IgY-related papers were obtained including 981 journal articles and 48 reviews. The visualization of this literature showed an increasing trend in the number of IgY-related publications over the 4 decades, especially after 2008 to 2021. China, the United States, Canada, Japan, and Germany had the largest number of publications, with 220, 148, 91, 76, and 72, respectively. Among all the research institutions, Dalian University of Technology, Alberta University and Northwest Agriculture and Forestry University published the most of the articles, respectively. Among authors, Dr. Xiaoying Zhang had the highest number of publications with 21. The top most cited publications were from Dr. da Silva with 38 citations. Keywords co-occurrence network analysis showed that the correlation between different keywords is large, especially IgY, antibodies and immunoglobulin which is consistent with the rapid increase in the number of publications. Finally, through this data analysis, we hope that our result could help IgY technology to more maturity toward industrialization and commercialization.

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, a series of vaccines, antibodies and drugs have been developed to combat coronavirus disease 2019 (COVID-19). High specific antibodies are powerful tool for the development of immunoassay and providing passive immunotherapy against SARS-CoV-2 and expected with large scale production. SARS-CoV-2 S1 protein was expressed in E. coli BL21 and purified by immobilized metal affinity chromatography, as antigen used to immunize hens, the specific IgY antibodies were extracted form egg yolk by PEG-6000 precipitation, and the titer of anti-S1 IgY antibody reached 1:10,000. IgY single chain variable fragment antibody (IgY-scFv) was generated by using phage display technology and the IgY-scFv showed high binding sensitivity and capacity to S1 protein of SARS-CoV-2, and the minimum detectable antigen S1 protein concentration was 6 ng/µL. The docking study showed that the multiple epitopes on the IgY-scFv interacted with multiple residues on SARS-CoV-2 S1 RBD to form hydrogen bonds. This preliminary study suggests that IgY and IgY-scFv are suitable candidates for the development of immunoassay and passive immunotherapy for COVID-19 to humans and animals. [ABSTRACT FROM AUTHOR]

Antibody mimetics may be used for various biomedical applications, especially those for which conventional antibodies are ineffective. In this study, we developed a smaller molecular chicken IgY mimetic peptide (IgY-peptide) based on the complementarity-determining regions (CDRs) of the anti-canine parvovirus (CPV) IgY-scFv prepared previously. The mimetic peptide showed no cross-reactivity with canine distemper virus (CDV) and canine coronavirus (CCV) and showed excellent protective properties for Crandell-Rees Feline Kidney (CRFK) cells against CPV. This study is the first attempt to develop a mimetic IgY-peptide and demonstrates the ease and feasibility in generating such a novel antibody-like functional molecule for biomedical purposes. [ABSTRACT FROM AUTHOR]

Background: Hot start can greatly improve specificity, sensitivity and yield of PCR. Non-specific amplification can occur in PCRwhen reaction mixture is prepared at roomtemperature, because Taq DNA polymerase is active and the primers can hybridize non-specifically. Hot start Taq DNA polymerases remain inactive at roomtemperature and are activated after heating at 95°C preventing non-specific amplification.Monoclonal antibodies against Taq DNA polymerase is the first line of reagents used for turn on regular Taq DNA polymerase into Hot start one. The goal of this research was to produce and evaluate Hot Start antibodies derived from chicken eggs. Results: We performed affinity purification of yolk immunoglobulin (IgY) and obtained polyclonal Hot Start antibodies. The yield of specific antibodies was 0.36 mg per egg or 0.2% of total yolk antibodies. The protocol for real time measurement and Hot start IgY activity assessment was developed. We found that Hot start IgY can reversibly block Taq DNA polymerase activity at 50°C and have no negative impact neither on the Taq DNA polymerase activity after denaturation nor on the reverse transcriptase. We estimated that 1.0 μg of Hot start IgY effectively blocks 5 U activity of Taq DNA polymerase. Conclusions: Egg derived Hot Start polyclonal antibodies are the cheapest source of Hot start antibodies, fromone immune egg we can isolate 0.36 mg IgY, this quantity is enough for producing 1800 U activity of Hot start Taq DNA Polymerase. [ABSTRACT FROM AUTHOR]

Rabbit and chicken (IgY) polyclonal antibodies were compared with respect to their performance in competitive enzyme linked immunoassays (ELISA) for the determination of opioid peptide β-casomorphin 7 (BCM-7) released from variant A1 of bovine β-casein. To obtain antibodies, the animals (four rabbits and four hens) were immunized (with similar regimes) with BCM-7 conjugated to bovine serum albumin. Comparison of the binding curves of biotinylated BCM-7 obtained with affinity-purified mammalian and avian antibodies immobilized on the surface of polystyrene microtiter immunoplates via passive adsorption (in optimal conditions) showed that rabbit antibodies captured biotinylated antigen 100 times more efficiently than hen antibodies within the given antibody panel. The most efficient rabbit antibodies were used to construct a highly sensitive, competitive ELISA for the detection of BCM-7 (the minimal detection limit was 0.2 ng/mL). The chicken antibodies proved unsuitable for such use due to their low affinity. These results indicate that it is necessary to make comparisons with methods based on mammalian antibodies in the construction of quantitative ELISA based on chicken polyclonal antibodies. [ABSTRACT FROM AUTHOR]

Egg yolk immunoglobulin (IgY) is a class of antibody that is produced in birds against pathogens. Therefore, hyperimmunization of birds can produce a specific antibody in the egg against target antigen for a wide range of applications in diagnostic, prophylactic or treatment in human and veterinary medicine which is known today as IgY technology. Until now, the number of articles, patents and clinical studies on IgY technology has increased significantly. Hence, there is a fact that scientometric studies are needed to gain a deeper understanding of the research for the commercialization of IgY technology. Until now, no scientometric research has been directed toward IgY technology. In view of this, we conducted scientometric analysis in the WoS database. A total of 1,029 IgY-related papers were obtained including 981 journal articles and 48 reviews. The visualization of this literature showed an increasing trend in the number of IgY-related publications over the 4 decades, especially after 2008 to 2021. China, the United States, Canada, Japan, and Germany had the largest number of publications, with 220, 148, 91, 76, and 72, respectively. Among all the research institutions, Dalian University of Technology, Alberta University and Northwest Agriculture and Forestry University published the most of the articles, respectively. Among authors, Dr. Xiaoying Zhang had the highest number of publications with 21. The top most cited publications were from Dr. da Silva with 38 citations. Keywords co-occurrence network analysis showed that the correlation between different keywords is large, especially IgY, antibodies and immunoglobulin which is consistent with the rapid increase in the number of publications. Finally, through this data analysis, we hope that our result could help IgY technology to more maturity toward industrialization and commercialization. [ABSTRACT FROM AUTHOR]

Avian antibodies (IgY) display some advantages in relation to the mammalian IgG antibodies due to its easy procedure for generation and purification and besides for its lower production cost. The objective of this work was to analyze the feasibility of binding IgY antibodies to polystyrene particles and to evaluate its performance in latex-agglutination tests in slide. For this purpose, the detection of hepatitis B surface antigen (HBsAg) was used as a model. Leghorn hens were immunized with the active pharmaceutical ingredient (MPA) used in the manufacturing of the Cuban recombinant vaccine Heberbiovac HB. The obtained antibodies were purified and used in the preparation of the latex particles (0.8 µm) for the detection of the HBsAg by agglutination. The performance of the test was evaluated with 50 serum samples against similar commercial reagent. The results obtained were satisfactory and demonstrated the feasibility of binding such avian antibodies to latex particles. These results open a perspective to the use of this type of assay for the rapid diagnostic of many diseases. [ABSTRACT FROM AUTHOR]

Abstract: Bovine respiratory syncytial virus (BRSV) and its counterpart in humans (HRSV) are two closely related virus, which are the leading cause of severe respiratory syndrome in calves and young children, respectively. Passive immunization can be a practical alternative to conventional vaccination in order to prevent the disease. In this report the production of chicken egg yolk IgY and its ability to neutralize BRSV in vitro were assessed. Purified IgY against BRSV specifically recognized BRSV in a dot blot assay and was able to neutralize the virus in a viral neutralization assay. These results demonstrate the potential use of IgY as a prophylactic treatment against RSV infection. [Copyright &y& Elsevier]

Abstract: Shiga toxins (Stx1 and Stx2) are the main virulence factors of enterohemorrhagic Escherichia coli (EHEC), a foodborne pathogen associated with diarrhea, hemorrhagic colitis and hemolytic uremic syndrome. The aim of this study was to evaluate the antibodies against Stx2 obtained from egg yolks of laying hens immunized with a recombinant Stx2B subunit. A high specific response in serum was observed 25 days after the first immunization and IgY antibodies were extracted from day 47th and purified from egg yolk. A concentration of 0.84 mg of total IgY/ml of egg yolk was obtained, of which 8% were antigen specific. The ability of anti-Stx2B IgY to recognize Stx2B and Stx2 either in solid-phase or in solution were evaluated and compared with anti-Stx2B rabbit antibodies by Western blotting and ELISA. The protective efficacy of IgY against Stx2 was determined by in vitro and in vivo experiments. The results show that IgY was able to recognize Stx2B and Stx2 in denatured conditions, attached to a solid-phase and free in solution. The anti-Stx2B IgY could effectively block the biological activity of Stx2 on Vero cells and protect mice from Stx2 challenge. The data suggest that immunization of hens with Stx2B could be a strategy to obtain at low cost a relatively high concentration of anti-Stx2 egg yolk IgY, able to neutralize Stx2 lethal activity. IgY technology could be an useful tool for research, diagnosis and therapy of EHEC infection. [Copyright &y& Elsevier]

The term "IgY technology" was introduced in the literature in the mid 1990s to describe a procedure involving immunization of avian species, mainly laying hens and consequent isolation of the polyclonal IgYs from the "immune" egg yolk (thus avoiding bleeding and animal stress). IgYs have been applied to various fields of medicine and biotechnology. The present article will deal with specific aspects of IgY technology, focusing on the currently reported methods for developing, isolating, evaluating and storing polyclonal IgYs. Other topics such as current information on isolation protocols or evaluation of IgYs from different avian species are also discussed. Specific advantages of IgY technology ( e.g. , novel antibody specificities that may emerge via the avian immune system) will also be discussed. Recent in vitro applications of polyclonal egg yolk-derived IgYs to the field of disease diagnosis in human and veterinary medicine through in vitro immunodetection of target biomolecules will be presented. Moreover, ethical aspects associated with animal well-being as well as new promising approaches that are relevant to the original IgY technology ( e.g. , development of monoclonal IgYs and IgY-like antibodies through the phage display technique or in transgenic chickens) and future prospects in the area will also be mentioned., Competing Interests: Conflict-of-interest statement: Authors declare no conflict of interest for this article., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)