Efficacy evaluation of anti- DEC-IgY against antibiotic- resistant diarrhoeagenic Escherichia coli

Introduction. The rise of multi- drug- resistant bacteria poses a global threat. In 2017, the World Health Organization identified 12 antibiotic- resistant 'priority pathogens', including Enterobacteriaceae, highlighting the menace of Gram- negative bacteria. Diarrhoeagenic Escherichia coli (DEC)- induced diarrhoea is particularly problematic for travellers and infants. In contrast to other antibiotic alternatives, passive immunotherapy is showing promise by providing immediate and precise protection. However, mammalian- sourced antibodies are costly, hindering large - scale production. Egg- laying chickenderived IgY antibodies present a cost- effective, high - yield solution, revolutionizing antibody - based therapeutics compared to mammalian IgG. Hypothesis/Gap Statement. This study hypothesized that developing anti- DEC- IgY could combat DEC infections effectively. Aim. The primary aim was to develop anti- DEC- IgY and assess its potential in DEC- induced diarrhoeal management. Method. Chickens were immunized with DEC antigens to induce an immune response. IgY antibodies were extracted from immune eggs and purified using ion- exchange column chromatography. Anti- DEC- IgY's ability to inhibit DEC growth was evaluated through growth inhibition assays. Anti- DEC- IgY's capacity to prevent E. coli adhesion was assessed using mice intestinal mucosa. In vivo experiments measured pathogen colonization reduction and infection severity reduction. P values were calculated to confirm statistical significance. Result. The antibacterial efficacy of anti- DEC- IgY by growth inhibition assay demonstrated that 25 mg ml-1 of IgY could inhibit the DEC growth. The anti- adherence- property was tested using mice intestinal mucosa and found that anti- DEC- IgY could prevent the E. coli adhesion. In vivo results suggest that 12 mg ml-1 of IgY will reduce the pathogen colonization in intestine and reduce the severity of the infection. The P values between the experimental groups confirm the statistical significance of the findings. Conclusion. The study findings suggest that IgY- based passive immunotherapy could be a potential strategy for managing the risks associated with antibiotic- resistant bacterial infections. Additionally, this study paves the way for the development of IgYrelated research and applications in India.