Dataset Information

Egg yolk immunoglobulin (IgY) targeting SARS-CoV-2 S1 as potential virus entry blocker.

ABSTRACT:

Aims

COVID-19 pandemic caused by SARS-CoV-2 has become a public health crisis worldwide. In this study, we aimed at demonstrating the neutralizing potential of the IgY produced after immunizing chicken with a recombinant SARS-CoV-2 spike protein S1 subunit.

Methods and results

E. coli BL21 carrying plasmid pET28a-S1 was induced with IPTG for the expression of SARS-CoV-2 S1 protein. The recombinant His-tagged S1 was purified and verified by SDS-PAGE, Western blot and biolayer interferometry (BLI) assay. Then S1 protein emulsified with Freund's adjuvant was used to immunize layer chickens. Specific IgY against S1 (S1-IgY) produced from egg yolks of these chickens exhibited a high titer (1:25,600) and a strong binding affinity to S1 (K_D = 318 nmol L^-1 ). The neutralizing ability of S1-IgY was quantified by a SARS-CoV-2 pseudotyped virus-based neutralization assay with an IC₅₀ value of 0.99 mg ml^-1 . In addition, S1-IgY exhibited a strong ability in blocking the binding of SARS-CoV-2 S1 to hACE2, and it could partially compete with hACE2 for the binding sites on S1 by BLI assays.

Conclusions

We demonstrated here that after immunization of chickens with our recombinant S1 protein, IgY neutralizing antibodies were generated against the SARS-CoV-2 spike protein S1 subunit; therefore, showing the potential use of IgY to block the entry of this virus.

Significance and impact of the study

IgY targeting S1 subunit of SARS-CoV-2 could be a promising candidate for pre- and post-exposure prophylaxis or treatment of COVID-19. Administration of IgY-based oral preparation, oral or nasal spray may have profound implications for blocking SARS-CoV-2.

SUBMITTER: Bao L

PROVIDER: S-EPMC8657347 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundEnterotoxigenic Escherichia coli K88 (E. coli K88) are considered as a major cause of diarrhea and death in newly weaned piglets. Oral passive immunization with chicken egg yolk immunoglobulins (IgY) have attracted considerable attention for treatment of gastrointestinal infection due to its high specificity. In this study it was estimated the protective effect of anti-K88 fimbriae IgY against E. coli K88 adhesion to piglet intestinal mucus in vitro and to investigate the potential use of IgY for controlling E. coli-induced diarrhea in weaned piglets in vivo.ResultsE. coli K88 was incubated with IgY for 24?h, and the bacterial growth profiles showed that specific IgY with a concentration higher than 5?mg/mL was observed to significantly inhibit the growth of E. coli K88 compared to nonspecific yolk powder in a liquid medium. Moreover, pretreatment with 50?mg/mL of IgY was found to significantly decrease the adhesion ability of E. coli K88 to porcine jejunal and ileal mucus, further supported by the observations from our immunofluorescence microscopic analysis. In vivo, administration of IgY successfully protected piglets from diarrhea caused by E. coli K88 challenge. Additionally, IgY treatment efficiently alleviated E. coli-induced intestinal inflammation in piglets as the gene expression levels of inflammatory cytokines TNF-?, IL-22, IL-6 and IL-1? in IgY-treated piglets remained unchanged after E. coli K88 infection. Furthermore, IgY significantly prevented E. coli K88 adhering to the jejunal and ileal mucosa of piglets with E. coli infection and significantly decreased E. coli and enterotoxin expression in colonic contents.ConclusionOutcome of the study demonstrated that IgY against the fimbrial antigen K88 was able to significantly inhibit the growth of E. coli K88, block the binding of E. coli to small intestinal mucus, and protect piglets from E. coli-induced diarrhea. These results indicate that passive immunization with IgY may be useful to prevent bacterial colonization and to control enteric diseases due to E. coli infection. The study has great clinical implication to provide alternative therapy to antibiotics in E coli induced diarrhea.

Project description:Drugs that are commonly used in poultry farms can potentially cause a detrimental effect on meat consumers as a result of chemical residues. Therefore, seeking a natural alternative is crucial for the health of the consumers. The egg yolk immunoglobulin Y (IgY) is a promising natural replacement for antibiotics in the broilers' diet. There is a scarce focus on the influence of probiotics and IgY on the quality and the nutritive values of broiler meat and whether it can efficiently displace the anti-microbial power of antibiotics. Herein we used 40 Ross chicks (1.2 ± 0.43 days old) and separated them into four groups with variant feed additives (basal diet "control," probiotic, IgY, and probiotic + IgY). Our findings showed that the combination of probiotic and IgY supplementation enhanced the carcass quality traits and decreased the pH values that could retard spoilage due to bacteria and improve shelf life and meat quality. The same group also achieved a significant reduction in thiobarbituric acid value, indicating an improvement of meat quality. Moreover, color, shear force, water holding capacity, and cooking loss were most acceptable in broiler meat supplemented with IgY, which confirmed the highest carcass quality. Notably, the weight gain in the combination group has been greatly increased. Also, the protein percentage was the highest (22.26 ± 0.29, P < 0.001) in this combined supplementation group, which revealed the highest nutritive values. Staphylococcus aureus and Escherichia coli could not be detected in the meat of the probiotics group and/or in the combined treatment group. Interestingly, the IgY group showed an evidence of the killing power (log colony-forming units per milliliter) of S. aureus and Listeria monocytogenes at 1,500 μg/ml. Our findings, in vitro as well as in vivo, revealed that the combination group had antimicrobial bioactivity and enhanced the chickens' immunity. Therefore, IgY, a novel trend of feed additives, can be used to limit drugs. Additionally, the mortality percentage recorded was zero in all groups that received feed supplementation, while the combination group reached the best financial advantages. We concluded that feeding IgY powder with probiotic is a frontier to improve the productivity, immunity, and meat quality of broilers.

Project description:BackgroundIgY antibodies are serum immunoglobulin in birds, reptiles and amphibians, and are transferred from serum to egg yolk to confer passive immunity to their embryos and offspring. Currently, the oral passive immunization using chicken IgY has been focused as an alternative to antibiotics for the treatment and control of diarrhea in animals and humans. This systematic review was focused to determine the effect of IgY in controlling and preventing diarrhea in domesticated animals including Piglets, Mice, Poultry and Calves.Methods and resultsPrevious research reports focused on treatment effect of Chicken IgY against diarrhea were retrieved from different electronic data bases (MEDLINE, EMBASE, SPRINGER-LINK, WILEY, AGRICOLA, MEDWELL Journals, Scientific Publish, Chinese articles from Core periodicals in 2012). A total of 61 studies in 4 different animal classes met the inclusion criteria. Data on study characteristics and outcome measures were extracted. The pooled relative risk (RR) of 49 studies of different animals [Piglets--22; Mice--14; Poultry--7 and Calves--6] in meta-analyses revealed that, IgY significantly reduced the risk of diarrhea in treatment group when compare to the placebo. However, the 95% confidence intervals of the majority of studies in animal class piglets and calves embrace RR of one. The same results were obtained in sub group analyses (treatment regiment--prophylactic or therapeutic; pathogen type--bacterial or viral). Perhaps, this inconsistency in the effect of IgY at the individual study level and overall effect measures could be influenced by the methodological heterogeneity.ConclusionThe present systematic review (SR) and meta-analysis demonstrated the beneficial effect of IgY. This supports the opinion that IgY is useful for prophylaxis and treatment. However, more intensive studies using the gold standard animal experiments with the focus to use IgY alone or in combination with other alternative strategies are indispensable.