Simple and efficient protocol for immunoglobulin Y purification from chicken egg yolk

A comparison between different chemical fractionation methods for immunoglobulin preparation

BACKGROUND

Application of antibodies in therapeutics and diagnostics are growing Continually. Herein, we aimed to find the most qualified immunoglobulin (Ig) chemical preparation method.

METHODS

A rabbit was immunized against recombinant SARS-CoV-2 nucleocapsid (NP) and reactive polyclonal antibodies were prepared using the ammonium sulfate (AS), caprylic acid (CA), polyethylene glycol (PEG), and caprylic acid/ammonium sulfate (CA/AS) methods. Different antibody solutions were analyzed by SDS-PAGE and subsequently quantified by ImageJ software for further analysis in terms of Ig purity, Ig recovery, and albumin impurity. Ultimately, the prepared antibodies were assessed via Western blotting and ELISA to evaluate their ability to bind NP.

RESULTS

Prepared Ig solutions via the CA/AS method had the highest Ig purity (followed by CA, PEG, and AS) and lowest albumin impurity (followed by CA, AS, and PEG). The PEG method had the highest recovery followed by AS, CA, and CA/AS methods. Moreover, antibodies prepared via different methods demonstrated comparable binding capacities to NP in ELISA and Western blotting.

CONCLUSIONS

CA/AS, closely followed by CA, proved to be the most qualified method for the preparation of Ig yielding the highest Ig purity while the PEG method resulted in the highest Ig recovery rate.

Comparison of immunoglobulin Y antibody production in new and spent laying hens

Background and Aim

Immunoglobulin (Ig)Y, a specific type of Ig found in chicken eggs, has potential use in the diagnosis of human and animal diseases. This study assessed the feasibility of using spent laying hens to produce IgY. In addition, the effects of antigen injection on egg and antibody production in new and spent laying hens were compared.

Materials and Methods

Hens were intramuscularly injected with three booster shots of antigens. IgY was extracted from egg yolks using polyethylene glycol 6000 precipitation followed by dialysis.

Results

Spent laying hens (83 weeks) consistently showed lower egg production than new laying hens (27 weeks) throughout the study. Post-immunization, a further decline in egg production was observed in spent laying hens, and egg production stopped after the second antigen injection. Eggs from spent laying hens were less dense than eggs from new hens. Despite lower IgY levels in eggs from spent laying hens, the heavy-to-light chain ratio remained consistent in both groups. Notably, IgY from spent and new laying hens demonstrated effective hemagglutination against cat erythrocytes in the A blood group.

Conclusions

This study demonstrated the potential of using spent laying hens to produce IgY, with significant implications for future research, immunotherapy, and diagnostic applications, despite the observed reduction in egg production compared with new laying hens.

Effects of feeding chicken egg yolk antibodies on intestinal cell apoptosis, oxidative stress and microbial flora of tilapia (Oreochromis niloticus) infected with Streptococcus agalactiae

Streptococcosis, the most common bacterial disease of fish in recent years, is highly infectious and lethal, and has become an important factor hindering the healthy and sustainable development of aquaculture. Chicken egg yolk antibody (IgY) has the advantages of high antigen specificity, inexpensive and easy to obtain, simple preparation, no toxic side effects, and in line with animal welfare, which is a green and safe alternative to antibiotics. In this study, the potential of specific IgY in the treatment of gastrointestinal pathogens was explored by observing the effects of specific IgY on intestinal flora, pathological tissue, apoptosis, oxidative stress, and inflammatory response of tilapia. We used the specific IgY prepared in the early stage to feed tilapia for 10 days, and then the tilapia was challenged with Streptococcus agalactiae. The results showed that feeding IgY before challenge had a small effect on the intestinal flora, and after challenge specific IgY decreased the proportion of Streptococcus and increased the diversity of the intestinal flora; in histopathology, specific IgY decreased tissue damage and maintained the integrity of tissue structure. Further study found that specific IgY can reduce intestinal epithelial cell apoptosis and reduce caspase activity; at the same time, the content of MDA was decreased, and the activities of SOD, CAT, GSH-Px and GR were increased. In addition, specific IgY can down-regulate the expression levels of IL-8 and TNF-α genes and up-regulate the expression levels of IL-10 and TGF-β. The results of this study showed that specific IgY could improve the intestinal flora of tilapia infected with Streptococcus agalactiae, reduce intestinal cell apoptosis, oxidative stress injury and inflammatory response, thereby reducing tissue damage and protecting the health of tilapia. Overall, specific IgY can be further explored as a potential antibiotic alternative for gastrointestinal pathogen infections.

Research Note: A novel method for preparation of egg yolk immunoglobulin Y against Porphyromonas gingivalis

Porphyromonas gingivalis (P. gingivalis, P. g) is the main pathogen of periodontal disease, which is treated with egg yolk immunoglobulin Y (IgY) against P. gingivalis. In order to quickly obtain IgY, 30 hens were immunized with inactivated P. gingivalis. The purification of IgY was carried out by the oleic acid (OA) method and the classical method (AS), respectively. The IgY antibody characteristics and antibacterial effects in HPDLF cells were detected by SDS-PAGE, indirect ELISA, Western blot and viability/toxicity assays. SDS-PAGE and Western blot analysis showed that IgY molecules which were rapidly purified by OA method were complete and specific to P. gingivalis. In addition, the results of crystal violet staining and bacterial staining indicated that IgY could agglutinate with P. gingivalis, inhibiting bacterial invasion of host cells. This study is the first to rapidly and efficiently purify IgY by OA method, and the purified IgY is expected to be used in the detection and treatment of P. gingivalis.

IgYs: on her majesty's secret service

There has been an increasing interest in using Immunoglobulin Y (IgY) antibodies as an alternative to "classical" antimicrobials. Unlike traditional antibiotics, they can be utilized on a continual basis without leading to the development of resistance. The veterinary IgY antibody market is growing because of the demand for minimal antibiotic use in animal production. IgY antibodies are not as strong as antibiotics for treating infections, but they work well as preventative agents and are natural, nontoxic, and easy to produce. They can be administered orally and are well tolerated, even by young animals. Unlike antibiotics, oral IgY supplements support the microbiome that plays a vital role in maintaining overall health, including immune system function. IgY formulations can be delivered as egg yolk powder and do not require extensive purification. Lipids in IgY supplements improve antibody stability in the digestive tract. Given this, using IgY antibodies as an alternative to antimicrobials has garnered interest. In this review, we will examine their antibacterial potential.

Study on functional improvement of freeze-thaw egg yolk pellet by enzymatic hydrolysis

Freeze-thaw egg yolk pellet (FYP) could be produced as a by-product in the process of egg yolk immunoglobulin (IgY) extraction. The FYP contained many superior nutritional components like fresh egg yolk, but it has poor functionalities because of protein denaturation resulted from freezing treatment during IgY extraction. For the purpose of comprehensive utilization of egg yolk resources, FYP was subjected to enzymatic hydrolysis with alcalase to produce FYP hydrolysates (FYPh) with four enzyme concentrations of 250, 500, 1000 and 2000 U/g for improved functional properties. And then FYPh was spray dried to obtain hydrolyzed egg yolk pellet powder (HYP). Solubility, emulsifying property and surface hydrophobicity of HYP were investigated. The results showed that enzymatic hydrolysis could lead to noticeable changes in surface hydrophobicity, microstructure, solubility and emulsifying properties of HYP compared with the control group without enzymatic hydrolysis treatment. Solubility and emulsification stability index generally increased from 19 g/100 g, 12.33 to 87 g/100 g, 76.63 with increasing degree of hydrolyze, respectively. This study demonstrated that the functional properties of FYP could be effectively improved when the enzyme addition amount reached 1000 U/g. HYP prepared under this condition owes desirable solubility and emulsification, and has the potential of application in food industry.

IgY Antibodies as Biotherapeutics in Biomedicine

Since the discovery of antibodies by Emil Von Behring and Shibasaburo Kitasato during the 19th century, their potential for use as biotechnological reagents has been exploited in different fields, such as basic and applied research, diagnosis, and the treatment of multiple diseases. Antibodies are relatively easy to obtain from any species with an adaptive immune system, but birds are animals characterized by relatively easy care and maintenance. In addition, the antibodies they produce can be purified from the egg yolk, allowing a system for obtaining them without performing invasive practices, which favors the three “rs” of animal care in experimentation, i.e., replacing, reducing, and refining. In this work, we carry out a brief descriptive review of the most outstanding characteristics of so-called “IgY technology” and the use of IgY antibodies from birds for basic experimentation, diagnosis, and treatment of human beings and animals.

Exploring the potential usefulness of IgY for antiviral therapy: A current review

Immunoglobulin yolk (IgY) is therapeutic antibodies presented in yolk eggs of birds, reptiles, and amphibians. These proteins produced by the immune system of the animal, are capable of neutralizing antigenic molecules, including viral antigens, fulfilling a role in the body defense. The specificity of these antibodies and the facility for their production, make these molecules capable of being used as tools for diagnosis and immunotherapy. Regarding this last aspect, it is common knowledge that the field of virology, is racing against time in the development of new drugs and vaccines to try to contain pandemics and local epidemics and, in counterproposal, avian antibodies are neutralizing molecules that can help in the control and spread of disease. These molecules have been explored for years and currently chicken eggs are produced in large quantities from the animal's immunization against a specific pathogen. Thus, on this subject, this review made a survey of these researches and presents a summary of all the successful cases and perspectives in the use of IgYs as tools for viral immunization.

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.