Production and Characterization of IgY Polyclonal Antibodies Specific to Human Interleukin-6 and Their Neutralization Potential for Anti-inflammatory Responses.

Background: Interleukin-6 plays an essential role in cytokine storm and cytokine release syndrome, which occur in response to pathogen infection or tissue injury and are associated with severe symptoms. Neutralizing IL-6 can help reduce symptom severity. Chicken eggs serve as an excellent alternative antibody source compared to mammalian serum. The immunoglobulin Y (IgY) in the chicken's blood is transferred to and deposited within the egg yolk in large amounts. Several IgY products have been developed for therapeutic applications in various diseases. This study focuses on producing anti-human IL-6 (IL-6) IgY antibodies to support therapeutic advancements. Methods: Anti-IL-6 IgY was generated by immunizing three hens with recombinant IL-6 protein mixed with alum adjuvant, immunized four times at three-week intervals. Then, IgY was extracted from egg yolks. The specificity of IgY was determined by Western blot. The neutralizing activity against secreted IL-6 was demonstrated by Human Coronavirus OC43 (HCoV-OC43)-infected cells and Lipopolysaccharide (LPS)-stimulated human lung fibroblast MRC-5 cells. Results: The specific anti-IL-6 was detected starting from day 10 to day 90 after immunization. The average yield of total IgY was 17.97±15.66 mg per egg. The extracted anti-IL6 IgY antibody exhibited efficient neutralizing effects against secreted IL-6 in the HCoV-OC43-infected or LPS-stimulated cells in a dose-dependent manner. Conclusion: This study highlights the ease of production and the satisfactory yield of anti-IL-6 IgY derived from chicken eggs. The antibody demonstrates an in vitro inhibitory effect on IL-6, with potential applications in therapeutic development.