Feasibility of polyclonal avian immunoglobulins (IgY) as prophylaxis against human norovirus infection

Background: Human norovirus (HuNoV) is the leading viral cause of diarrhea, with GII.4 as the predominant genotype of HuNoV outbreaks globally. However, new genogroup variants emerge periodically, complicating the development of anti-HuNoV vaccines; other prophylactic or therapeutic medications specifically for HuNoV disease are lacking. Passive immunization using oral anti-HuNoV antibodies may be a rational alternative. Here, we explore the feasibility of using avian immunoglobulins (IgY) for preventing HuNoV infection in vitro in a human intestinal enteroid (HIE) model. Methods: Hens were immunized with virus-like particles (VLP) of a GII.4 HuNoV strain (GII.4/CHDC2094/1974/US) by intramuscular injection. The resulting IgY was evaluated for inhibition of binding to histo-blood group antigens (HBGA) and viral neutralization against representative GII.4 and GII.6 clinical isolates, using an HIE model. Results: IgY titers were detected by three weeks following initial immunization, persisting at levels of 1:221 (1:2,097,152) from 9 weeks to 23 weeks. Anti-HuNoV IgY significantly (p < 0.05) blocked VLP adhesion to HBGA up to 1:12,048 dilution (0.005 mg/mL), and significantly (p < 0.05) inhibited replication of HuNoV GII.4[P16] Sydney 2012 in HIEs up to 1:128 dilution (0.08 mg/mL). Neutralization was not detected against genotype GII.6. Conclusions: We demonstrate the feasibility of IgY for preventing infection of HIE by HuNoV GII.4. Clinical preparations should cover multiple circulating HuNoV genotypes for comprehensive effects. Plans for animal studies are underway.Instituto de VirologíaFil: Artman, Chad. Scaled Microbiomics; Estados UnidosFil: Idegwu, Nnebuefe. Scaled Microbiomics; Estados UnidosFil: Brumfield, Kyle D. College Park Campus. University of Maryland. Maryland Pathogen Research Institute; Estados UnidosFil: Brumfield, Kyle D. College Park Campus. University of Maryland. University of Maryland Institute for Advanced Computer Studies; Estados UnidosFil: Lai, Ken. University of Saskatchewan. Vaccine and Infectious Disease Organization; CanadáFil: Hauta, Shirley. University of Saskatchewan. Vaccine and Infectious Disease Organization; CanadáFil: Falzarano, Darryl. University of Saskatchewan. Vaccine and Infectious Disease Organization; CanadáFil: Falzarano, Darryl. University of Saskatchewan. Western College of Veterinary Medicine. Department of Veterinary Microbiology; CanadáFil: Parreño, Gladys Viviana. Virginia-Maryland College of Veterinary Medicine. Department of Biomedical Sciences and Pathobiology; Estados UnidosFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). INCUINTA. Instituto de Virologia e Innovaciones Tecnologicas (IVIT); ArgentinaFil: Yuan, Lijuan. Virginia-Maryland College of Veterinary Medicine. Department of Biomedical Sciences and Pathobiology; Estados UnidosFil: Geyer, James D. University of Alabama. College of Community Health Science. Institute for Rural Health Research; Estados UnidosFil: Goepp, Julius G. Scaled Microbiomics; Estados Unido