The COVID-19 pandemic has led to an increased interest in the study of IgY (Immunoglobulin Y) as a potential inhibitor of SARS-CoV-2, the causative agent of COVID-19. IgY is a type of antibody found in birds, and reptiles, and it is similar in structure and function to the mammalian immunoglobulin G (IgG) antibody. Therefore IgY would be a possible passive immunotherapeutic against SARS-CoV-2. In this study specific IgY antibodies were produced against the SARS-CoV-2 virus by vaccination of SPF laying hens. Babcock SPF laying hens were injected with a vaccine containing 10 μg SARS-CoV-2 S antigen mixed with water-in-oil type adjuvant. The first vaccination of the hens was accomplished at 18 weeks of age, then it was repeated three times. Subsequently an HCl-NH3SO4 precipitation technique was used to extract the IgY from egg yolk, and the purity was examined by SDS-PAGE. The SARS-CoV-2 inhibitory activity was tested using a virus neutralization assay. Syrian hamsters are considered a good model for studying SARS-CoV-2 as they are susceptible to the virus infection and develop symptoms that are similar to those seen in humans. Syrian hamsters received IgY or PBS (control) one hour before the virus infection, then every 8 hours in the first three days. Then from the fourth to the fifth day treatment was done twice a day. Oropharyngeal sampling was done every day once. Viral replication was analyzed with droplet-digital PCR. The majority of the samples in the IgY-treated group proved to be negative for SARS-CoV-2, while in the control group strong viral replication was measured. Furthermore, the control group developed severe pneumonia than the IgY-treated group. however, the virus was detected in some lung samples of the IgY-treated groups as well. Overall, our results indicate the potential use of IgY as a treatment for SARS-CoV-2, but further studies are needed to fully understand and confirm its efficacy.
Audience take away:
- Possible information on the protective effect of IgY against SARS 2 infection
- What is IgY antibodies (special knowledge)
- The audience could use the information for teaching or researching
- Pharmaceutical/industrial usability?