Avian antibodies (IgY) against Trypanosoma cruzi: Purification and characterization studies

Avian Antibodies as Potential Therapeutic Tools

Immunoglobulin Y (IgY) is the primary antibody found in the eggs of chicken (Gallus domesticus), allowing for large-scale antibody production with high titers, making them cost-effective antibody producers. IgY serves as a valuable alternative to mammalian antibodies typically used in immunodiagnostics and immunotherapy. Compared to mammalian antibodies, IgY offers several biochemical advantages, and its straightforward purification from egg yolk eliminates the need for invasive procedures like blood collection, reducing stress in animals. Due to the evolutionary differences between birds and mammals, chicken antibodies can bind to a broader range of epitopes on mammalian proteins than their mammalian counterparts. Studies have shown that chicken antibodies bind 3-5 times more effectively to rabbit IgG than swine antibodies, enhancing the signal in immunological assays. Additionally, IgY does not interact with rheumatoid factors or human anti-mouse IgG antibodies (HAMA), helping to minimize interference from these factors. IgY obtained from egg yolk of hens immunized against Pseudomonas aeruginosa has been used in patients suffering from cystic fibrosis and chronic pulmonary colonization with this bacterium. Furthermore, IgY has been used to counteract streptococcus mutans in the oral cavity and for the treatment of enteral infections in both humans and animals. However, the use of avian antibodies is limited to pulmonary, enteral, or topical application and should, due to immunogenicity, not be used for systemic administration. Thus, IgY expands the range of strategies available for combating pathogens in medicine, as a promising candidate both as an alternative to antibiotics and as a valuable tool in research and diagnostics.

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.

Avian anti-HBV immunoglobulin: New tool to improve hepatitis B diagnosis methods

Immunoglobulin Y (IgY) could be used in serological diagnosis focused on several infectious agents. This study aims to produce IgY anti-hepatitis B virus surface antigen (anti-HBs) and to assess its use in enzyme immunoassays. Antibodies were produced by immunizing chickens with Hepatitis B vaccine associated (group A), or not, with adjuvant CpG-ODN (group B). Eggs were collected for 20 weeks, yolks were purified based on using polyethylene glycol and affinity chromatography. IgY anti-HBs was featured based on SDS-PAGE and Western Blot techniques. Total protein concentration was measured through spectrophotometry. In-house ELISA used to detect HBsAg was developed based on using IgG/HRP conjugate and IgY-anti-HBs sensitized microplates. Thus, IgY anti-HBs were confirmed through molecular pattern based on SDS-PAGE, whereas specificity of anti-HBs was confirmed through Western Blot. Mean total protein reached 3.27 ± 3.00 mg/mL and 3.11 ± 3.12 mg/mL in groups A and B, respectively. In-house ELISA was developed based on using a panel of HBV positive and negative serum samples; it recorded 100 % sensitivity and 78.9 % specificity to detect HBsAg. In conclusion, it was possible producing anti-HBs IgY by immunizing chickens with HBV vaccine; this molecule could be used as capture antibody to help detecting HBsAg in-house ELISA.

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.

Hyperimmunized Chickens Produce Neutralizing Antibodies against SARS-CoV-2

The novel severe acute respiratory syndrome (SARS) coronavirus, SARS-CoV-2, is responsible for the global COVID-19 pandemic. Effective interventions are urgently needed to mitigate the effects of COVID-19 and likely require multiple strategies. Egg-extracted antibody therapies are a low-cost and scalable strategy to protect at-risk individuals from SARS-CoV-2 infection. Commercial laying hens were hyperimmunized against the SARS-CoV-2 S1 protein using three different S1 recombinant proteins and three different doses. Sera and egg yolk were collected at three and six weeks after the second immunization for enzyme-linked immunosorbent assay and plaque-reduction neutralization assay to determine antigen-specific antibody titers and neutralizing antibody titers, respectively. In this study we demonstrate that hens hyperimmunized against the SARS-CoV-2 recombinant S1 and receptor binding domain (RBD) proteins produced neutralizing antibodies against SARS-CoV-2. We further demonstrate that antibody production was dependent on the dose and type of antigen administered. Our data suggests that antibodies purified from the egg yolk of hyperimmunized hens can be used as immunoprophylaxis in humans at risk of exposure to SARS-CoV-2.

IgY technology: Methods for developing and evaluating avian immunoglobulins for the in vitro detection of biomolecules

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.

Tecnología IgY: Estrategia en el tratamiento de enfermedades infecciosas humanas

La aparición de microorganismos resistentes a antibióticos, el descubrimiento de nuevos agentes patógenos con potencial pandémico y el aumento de una población inmunocomprometida han dejado casi obsoleta la terapia antimicrobiana, terapia comúnmente usada para tratar enfermedades infecciosas. Por otro lado, las investigaciones acerca del uso del anticuerpo IgY para desarrollar inmunidad pasiva han demostrado el potencial que tiene la tecnología IgY para tratar enfermedades infecciosas víricas y bacterianas. Donde los anticuerpos IgY de aves se destacan por su alta especificidad, rendimiento y escalabilidad de producción a menor costo, con relación a los anticuerpos IgG de mamíferos. El objetivo de esta revisión es determinar la importancia del uso de los anticuerpos IgY como tratamiento terapéutico y profiláctico frente a los patógenos causantes de infecciones virales y bacterianas en humanos, mediante la recopilación de ensayos clínicos, productos comerciales y patentes registradas en el período de 2010-2021. Finalmente, con este estudio se estableció que la tecnología IgY es una herramienta biotecnológica versátil y eficaz para tratar y prevenir enfermedades infecciosas, al reducir los síntomas y la carga del patógeno.

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.

Chicken egg yolk antibody (IgY) as diagnostics and therapeutics in parasitic infections - A review

Early diagnosis and treatment of parasitic diseases are indispensable to combat parasites mediated morbidity and mortality in humans and animals. Mammalian sourced antibodies are being successfully used in immunotherapy and immunoassays. However, their increased conservation amongst mammals, involves them in unnecessary interaction and immune mediated pathologies, obstructing their applications in certain approaches in immunoassays. Further, the high production cost and difficulty to achieve high and stable antibody titer hampers their utility for therapeutic purposes. In recent years, chicken egg yolk immunoglobulin, termed as immunoglobulin Y (IgY) has attracted noticeable consideration since it poses greater advantages than mammalian IgG including high yield, low cost and convenience. IgY has unique properties which are being exploited in different aspects for its applications in research, diagnosis and therapy. This review gives an overview of the research outcomes pertaining to chicken IgY as diagnostics and therapeutics in parasitology.

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.

Ecto-enzymes activities in splenic lymphocytes of mice experimentally infected by Trypanosoma cruzi and treated with specific avian immunoglobulins: an attempt to improve the immune response

The aim of this study was to evaluate the therapeutic efficacy of specific avian polyclonal antibodies (IgY) against Trypanosoma cruzi and their interaction with ecto-enzymes of the purinergic system (NTPDase and adenosine deaminase (ADA) activities) in splenic lymphocytes. For this, mice were divided into six groups: three non-infected (A, B, and C) and three infected (D, E, and F). The groups A and D were composed by negative and positive controls, respectively; while the groups B and E were treated prophylactically with IgY (50 mg/kg), and the groups C and F were treated therapeutically with IgY (50 mg/kg). Treatment with IgY reduced parasitemia on day 6 post-infection (PI) compared to the infected control group, but it was similar on day 8 PI. Moreover, infected and treated animals (the groups E and F) did not show neither amastigotes in the cardiac tissue nor cardiac lesions when compared to the positive control group (the group D). The E-NTPDase (ATP and ADP as substrate) and ADA activities in splenic lymphocytes increased significantly in the positive control group (the group D) compared to the negative control group (the group A). The therapeutic treatment of IgY (the group F) was able to prevent the increase of E-NTPDase and E-ADA activities compared to the positive control group (the group D), but this finding was not observed in animals that received the prophylactic treatment (the group E). The therapeutic treatment of IgY may be considered an interesting approach to improve the immune response of mice experimentally infected by T. cruzi.