Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity

Characterization of anti-soybean agglutinin (SBA) IgY antibodies: a new strategy for neutralization of the detrimental biological activity of SBA

Anti-soybean agglutinin (SBA) IgY was produced, and its potential to neutralize the haemagglutinating activity of SBA in vitro was tested. Thirty-five-week-old hens [treatment (n = 5) and control (n = 5)] were immunized with SBA or injected with saline 4 times every 15 days. Eggs were collected after the last immunization, and IgY was extracted using the polyethylene glycol (PEG) method. Serum anti-SBA IgY titres in immunized hens increased after the first immunization and reached a plateau between days 45 and 60. In contrast, specific IgY titres in the control group remained at basal levels throughout the evaluation. Average IgY titres were significantly higher in the treatment group on days 15, 30, 45, and 60. Total IgY content in the egg yolk extract was 38.7 ± 1.6 and 37.7 ± 1.5 mg/ml for the treatment and control groups, respectively. The specific anti-SBA IgY titer detected in the egg yolk extract was significantly higher (p < 0.001) for hens in the treatment group compared to the control group, with OD450nm values of 0.98 ± 0.05 and 0.058 ± 0.02, respectively. The specificity of anti-SBA IgY was confirmed by the Western blotting, and the inhibition of SBA-induced haemagglutination in vitro was compared with D-galactose, a known molecule that binds to SBA and blocks its binding to erythrocytes. The inhibition of SBA-induced haemagglutination by the anti-SBA IgY reached 512 units of haemagglutination inhibition (UHI), compared to 8 or 256 UHI, respectively, when IgY from control chickens or D-galactose was used. Thus, anti-SBA IgY antibodies were efficiently produced in large quantities and effectively inhibited SBA-induced haemagglutination in vitro.

IgY Antibodies from Birds: A Review on Affinity and Avidity

IgY antibodies are found in the blood and yolk of eggs. Several studies show the feasibility of utilising IgY for immunotherapy and immunodiagnosis. These antibodies have been studied because they fulfil the current needs for reducing, replacing, and improving the use of animals. Affinity and avidity represent the strength of the antigen-antibody interaction and directly influence antibody action. The aim of this review was to examine the factors that influence the affinity and avidity of IgY antibodies and the methodologies used to determine these variables. In birds, there are few studies on the maturation of antibody affinity and avidity, and these studies suggest that the use of an adjuvant-type of antigen, the animal lineage, the number of immunisations, and the time interfered with the affinity and avidity of IgY antibodies. Regarding the methodologies, most studies use chaotropic agents to determine the avidity index. Studies involving the solution phase and equilibrium titration reactions are also described. These results demonstrate the need for the standardisation of methodologies for the determination of affinity and avidity so that further studies can be performed to optimise the production of high avidity IgY antibodies.

IgY antibodies: The promising potential to overcome antibiotic resistance

Antibiotic resistant bacteria are a growing threat to global health security. Whilst the emergence of antimicrobial resistance (AMR) is a natural phenomenon, it is also driven by antibiotic exposure in health care, agriculture, and the environment. Antibiotic pressure and inappropriate use of antibiotics are important factors which drive resistance. Apart from their use to treat bacterial infections in humans, antibiotics also play an important role in animal husbandry. With limited antibiotic options, alternate strategies are required to overcome AMR. Passive immunization through oral, nasal and topical administration of egg yolk-derived IgY antibodies from immunized chickens were recently shown to be effective for treating bacterial infections in animals and humans. Immunization of chickens with specific antigens offers the possibility of creating specific antibodies targeting a wide range of antibiotic-resistant bacteria. In this review, we describe the growing global problem of antimicrobial resistance and highlight the promising potential of the use of egg yolk IgY antibodies for the treatment of bacterial infections, particularly those listed in the World Health Organization priority list.

Immunoglobulin Y for Potential Diagnostic and Therapeutic Applications in Infectious Diseases

Antiviral, antibacterial, and antiparasitic drugs and vaccines are essential to maintaining the health of humans and animals. Yet, their production can be slow and expensive, and efficacy lost once pathogens mount resistance. Chicken immunoglobulin Y (IgY) is a highly conserved homolog of human immunoglobulin G (IgG) that has shown benefits and a favorable safety profile, primarily in animal models of human infectious diseases. IgY is fast-acting, easy to produce, and low cost. IgY antibodies can readily be generated in large quantities with minimal environmental harm or infrastructure investment by using egg-laying hens. We summarize a variety of IgY uses, focusing on their potential for the detection, prevention, and treatment of human and animal infections.

Egg yolk antibodies (IgY) and their applications in human and veterinary health: A review

Egg yolk constitutes a relevant alternative source of antibodies. It presents some advantages over mammalian serum immunoglobulins regarding productivity, animal welfare and specificity. The main immunoglobulin present in avian blood (IgY) is transmitted to their offspring and accumulates in egg yolks, which enables the non-invasive harvesting of high amounts of antibodies. Moreover, due to structural differences and phylogenetic distance, IgY is more suitable for diagnostic purposes than mammalian antibodies, since it does not react with certain components of the human immune system and displays greater avidity for mammalian conserved proteins. IgY has been extensively used in health researches, as both therapeutic and diagnostic tool. This article aims to review its applications in both human and veterinary health.

How Can the Value and Use of Egg Yolk Be Increased?

The major driving force for the egg consumption in the United States over the past few decades was processed egg. However, the consumption of egg through the processed egg reached the plateau in recent years because of the imbalance in the demands between the egg white and yolk products. The consumer demands for egg white products are very high while those for the egg yolk, the co-product of dried egg white, are low because of the negative perceptions on egg yolk. Two key approaches that can be used to increase the value and use of egg yolk are: (1) developing new commodity products by fractionating egg yolk and apply them in various food processing, and (2) separating functional proteins and lipids from yolk and use them as is or further develop functional peptides and functional lipids and use them as pharmaceutical, nutraceutical, and cosmeceutical agents. These approaches can diversify the use of egg yolk, which eventually will help increase the consumption of egg. This review (1) discusses the current use of egg yolk products and the development of new functional commodity products from egg yolk, (2) review the important functional components in egg yolk and overview the current separation methods and their applications, (3) discuss the production of functional peptides and lipids using the separated egg proteins and lipids, and (4) suggest the future directions for the best use of egg yolk components. Development of scale-up production methods, which is vital for the practical applications, is discussed when appropriate.

The complementarity-determining region sequences in IgY antivenom hypervariable regions

The data presented in this article are related to the research article entitled "Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity" (da Rocha et al., 2017) [1]. Complementarity-determining region (CDR) sequences are variable antibody (Ab) sequences that respond with specificity, duration and strength to identify and bind to antigen (Ag) epitopes. B lymphocytes isolated from hens immunized with Bitis arietans (Ba) and anti-Crotalus durissus terrificus (Cdt) venoms and expressing high specificity, affinity and toxicity neutralizing antibody titers were used as DNA sources. The VLF1, CDR1, CDR2, VLR1 and CDR3 sequences were validated by BLASTp, and values corresponding to IgY V_L and V_H anti-Ba or anti-Cdt venoms were identified, registered [Gallus gallus IgY Fv Light chain (GU815099)/Gallus gallus IgY Fv Heavy chain (GU815098)] and used for molecular modeling of IgY scFv anti-Ba. The resulting CDR1, CDR2 and CDR3 sequences were combined to construct the three - dimensional structure of the Ab paratope.