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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Exotic & Emerging Avian Viral Diseases Research » Research » Publications at this Location » Publication #347920

Research Project: Intervention Strategies to Prevent and Control Disease Outbreaks Caused by Emerging Strains of Avian Influenza Viruses

Location: Exotic & Emerging Avian Viral Diseases Research

Title: Purported addition of N-glycosylation sites on the globular head of the hemagglutinin induced escape of a 2015 Mexican H7 HPAI strain from vaccinal immunity

item CRIADO, MIRIA - Consultant
item BERTRAN, KATERI - Consultant
item LEE, DONG-HUN - Orise Fellow
item Killmaster, Lindsay
item STEPHENS, CHRISTOPER - Orise Fellow
item Spackman, Erica
item ATKINS, EMILY - Boehringer Ingelheim
item SA E SILVA, MARIANA - Boehringer Ingelheim
item MEBATSION, TESHOME - Boehringer Ingelheim
item SMITH, ROBERT - Boehringer Ingelheim
item HUGHES, TROY - Boehringer Ingelheim
item WIDENER, JUSTIN - Boehringer Ingelheim
item PRITCHARD, NIKKI - Boehringer Ingelheim
item Swayne, David

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2018
Publication Date: 4/15/2018
Citation: Criado, M.F., Bertran, K., Lee, D., Killmaster, L.F., Stephens, C.B., Spackman, E., Atkins, E., Sa E Silva, M., Mebatsion, T., Smith, R., Hughes, T., Widener, J., Pritchard, N., Swayne, D.E. 2018.[abstract] Purported addition of N-glycosylation sites on the globular head of the hemagglutinin induced escape of a 2015 Mexican H7 HPAI strain from vaccinal immunity. Abstract book for 10th International Symposium on Avian Influenza, Brighton, United Kingdom, April 15-18, 2018. Paper No. 50.

Interpretive Summary:

Technical Abstract: In the past years, H7N3 highly pathogenic avian influenza (HPAI) has been reported in Mexico with a dramatic economic and ethical impact due to the high number of birds that have died or been culled. In the present study, one-day-old specific pathogen free (SPF) leghorn chickens were vaccinated with two different constructs of recombinant fowlpox virus vaccine (r-FPV-H7/3002 and r-FPV-H7/2155) containing a low pathogenic AI (LPAI) H7 hemagglutinin (HA) insert, and were then subsequently challenged with H7N3 HPAI virus (A/chicken/ Jalisco/37905/2015). The vaccine containing the HA closely related to recent H7 strains, r-FPV-H7/3002, conferred protection to all birds against mortality and morbidity, and significantly reduced virus shed titers from the gastrointestinal tract. In contrast, 100% sham and r-FPV-H7/2155 birds shed virus at high titers and died within 4 days. Pre- (15/20) and post- (20/20) challenge serum of birds vaccinated with r-FPV-H7/3002 showed HI antibodies. However, few birds (3/20) in the r-FPV-H7/2155 group had antibodies against challenge strain than that of homologous antigen (20/20). Interestingly, we identified in silico potential additional N-glycosylation sites on the globular head of the H7 HA in Jalisco/37905/2015, which are absent in previous strains from the same area. The acquisition of additional N-glycosylation sites can prevent neutralization by antibodies directed against previous strains and escape from vaccine-induced immunity elicited by heterologous vaccines. Although the genetic evolution in H7 AI virus isolates has not led to significant antigenic diversity, this study confirms the relevance of updating vaccines for control of H7 HPAI virus in combination with strict epidemiological surveillance and biosecurity measures.