Biology subjects

Vaillant, A. A. J.

Publications and source records attributed to Vaillant, A. A. J..

5 recordsLinked to original sources

bioRxiv2021

In vivo administration of anti-HIV hyper-immune eggs induces anti-anti-idiotypic antibodies against HIV gp120 peptides (fragments 308-331 and 421-438) and against HIV gp41 peptide (fragment 579-601) which have demonstrable protective capacity.

Isolation of antibodies from the egg yolk of chickens is of particular interest as a source of specific antibodies for oral administration to prevent infections and use them as immunodiagnostic reagents. The use of birds in antibody production results in a reduction in the use of laboratory animals. Immunized chickens produce larger quantities of antibodies (2000 mg IgY/month) than rodents (200 mg IgG/month) in the laboratory. According to Jernes network theory, it is possible to produce an antibody against the antigen-binding site of another antibody. This study assessed the hypothesis that immunization with viral peptides (immunogens) could provide a potent immune response that could be evaluated in chicken eggs. Human immunodeficiency virus 1(HIV-1) is used as an immunogen. The second hypothesis was that an orally administered antibody stimulates the production of a complementary antibody, the so-called anti-idiotypic antibody, which can potentially be therapeutical. This study reports and analyzes the use of eggs as therapeutic agents. We wanted to test the hypothesis that feeding chicks with hyperimmune eggs stimulates the production of anti-anti-idiotypic antibodies that neutralize the original HIV antigen fragments 308-331 or 421-438 of gp120 or fragment 579-601 of gp41. Future research could entail an anti-idiotype strategy for prophylactic vaccines. It is vital to note that it may need an anti-idiotype response to prime immunity against an HIV viral epitope, which may be used as a secondary element. The use of anti-idiotype immune responses in infected individuals may shift the balance of the immune system, allowing the organism to manage HIV infection. Therefore, it may be an avenue for immunotherapy to improve the fight against HIV infections. However, more studies and clinical trials are required to demonstrate similar human immune responses as observed in birds.

immunology↗

bioRxiv2021

Production of antibodies in egg whites of chickens.

BackgroundIgM, which participates in the primary immune response, is the primary antibody in egg whites. There is scant information about the production of antibodies in egg whites. This study describes the preparation of antibodies against bacterial antigens. MethodsEnzyme-linked immunosorbent assay (ELISA) was used to detect the presence of anti-egg white antibodies. The antibodies were purified using affinity chromatography. Statistical analyses were performed using SPSS version 22. Statistical significance was set at P<0.05. ResultsLarge amounts of anti-protein A antibodies were produced in chicken egg whites. The generation of anti-SpA antibodies was demonstrated by affinity chromatography from 9 d post-immunization egg white samples. Inhibition of agglutination was observed in samples containing anti-SpA antibodies, and agglutination at the bottom of the wells was observed in the negative samples. ConclusionAnti-protein A antibodies (IgM) were produced in the egg whites of the immunized hens. Bacterial growth in blood agar plates was observed only in specimens plated with egg whites from pre-immunized birds. Protein A-affinity chromatography was helpful for the characterization of anti-protein A antibodies. Inhibition of these antibodies was observed in vitro.

immunology↗

bioRxiv2020

Universal enzyme-linked immunosorbent assays (ELISA) and utility in the immunodiagnosis of Salmonellosis

The aim of this study was to confirm the feasibility of using hybrid immunoglobulin-binding reagents in ELISAs for IgG/IgY detection and detection of specific antibodies against an infectious microorganism (Salmonella spp.) in various animal species using a universal diagnostic ELISA. Hybrid immunoglobulin-binding bacterial proteins (IBP), including recombinant protein LA, recombinant protein LG, and recombinant protein AG, have been produced to improve their binding affinity to a much larger number of immunoglobulins. Thus, this hybrid bacterial protein represents a powerful tool for the binding, detection, and purification of immunoglobulins and their fragments. However, SpLA-LG-peroxidase and SpLAG-anti-IgYperoxidase were produced using the periodate method. These compounds have been shown to be effective as reagents. Their binding affinity to immunoglobulins surpasses that of previously reported hybrid IgG-binding proteins, including the most known SpAG, SpLA, and SpLG. The IgY fraction was isolated from the egg yolks of various birds, including chicken, bantam hen, guinea hen, quail, goose, duck, wild and domestic pigeons, parakeets, cattle egrets, pheasants, and ostrich. The IgY fraction was isolated using the chloroform-polyethylene glycol (PEG) method. An ELISA for anti-Salmonella spp. antibodies was employed with some modifications to determine the presence of antibodies in humans, laying hens, geese, quails, and pigeons. Salmonella is a motile, flagellated, rod-shaped zoonotic pathogen that can survive in the presence or absence of oxygen. They belong to the family Enterobacteriaceae and are implicated in typhoid fever and food-borne illnesses. This pathogen is associated with several diseases, which may become fatal and negatively impact the health of individuals and various economies globally. The poultry industry is most vulnerable to the influence of this pernicious microbe. The authors concluded that universal enzyme-linked immunosorbent assays were effective and reproducible in detecting immunoglobulins from both avian and mammalian species, but ELISA using the SpLAG-anti-IgY-HRP conjugate only reacted with the whole panel of animal antibodies. This conjugate was further used to standardize a universal ELISA for the determination of anti-Salmonella antibodies, in which human and avian species were serologically assessed.

immunology↗

bioRxiv2020

Use of immunoglobulin-binding bacterial proteins in immunodetection.

One of the aim of this study was to make universal chimeric conjugates to react with both avian and mammalian immunoglobulins in enzyme-linked immunosorbent assays (ELISAs). The periodate method was used in the conjugation process of cross-linking horseradish peroxidase to immunoglobulin-binding proteins (IBP) including staphylococcal protein A (SpA), streptococcal protein G (SpG) and peptostreptococcal protein L (SpL). By mixing up these three conjugates another four hybrid protein conjugates were created including protein LA (SpLA), protein LG (SpLG), protein AG (SpAG) and protein LAG (PLAG). Thirty-five ELISAs were standardized by a probabilistic combination of these immunoreagents. By using a panel of mainly mammalian immunoglobulins their reproducibility was checked by the determination of coefficient of variations (CV) for each one of the IgG-IBP binding. The source of immunoglobulins was their purification by affinity chromatography using a commercially available kit (PURE-1A). The other aim was to immunize chicken with the peptide fragment 254-274 of gp120 to produce anti-HIV peptide hyper-immune egg. Cats and rats were fed these eggs for a determined period until they produced the anti-HIV peptide antibody, which was tested by an indirect SpLA-ELISA and dot blot analysis that corroborated the production of anti-HIV antibodies by the mammalian species including positive humans samples for HIV. We conclude that the single and hybrid immunoglobulin-binding protein were effective in their binding capacity to immunoglobulins from a variety of mammalian species. The potential use of this proteins is in the arena of immunodiagnosis and immunoglobulin detection. Dot blot analysis proves effective in the detection of HIV anti-gp120 antibodies in several animal species. These antibodies can be used as reagents in the development of immunodiagnostic tests or experimental vaccines.

immunology↗

bioRxiv2020

Immunogenicity studies of various experimental vaccines in chickens.

In this paper, the main objective was to raise chickens antibodies against three crucial public health microorganisms: the human immunodeficiency virus-1, Salmonella spp, and Staphylococcus aureus. Immunogens were prepared from the said microorganisms. Chickens were vaccinated either orally or intramuscularly. After a booster immunization, mostly eggs were collected and assess for the presence of specific antibodies. The most important results were the production of a large amount of anti-HIV antibodies in chickens eggs, and also the synthesis of anti-protein A antibodies with the ability to inhibit the growth of S. aureus in vitro and to serve as anti-anti-idiotypic antibodies with the capacity of neutralizing the original antigen. Enzyme-linked immune absorbent assays detected the presence of these antibodies as anti-Salmonella antibodies that were critical in reducing the bacterial load in the stomach and caeca compared with a control group. The vaccines were effective and safe, but more laboratory work, and economics have to be carried out to start a human trial.

immunology↗