Influenza A virus receptor distribution in the lactating mammary gland of domesticated livestock in the US 9374

Abstract Description The spread of the Highly Pathogenic Avian Influenza (HPAI) H5N1 virus into dairy cattle, particularly affecting the mammary gland and milk, underscores the remarkable adaptability of Influenza A Viruses (IAV) to infect non-traditional species and facilitate cross-species transmission. Potential widespread transmission of HPAI H5N1 into other production mammalian species will have profound economic (> $30 billion) and agricultural impacts. A key innate immune factor influencing the susceptibility of these animals to HPAI H5N1 infection is the presence of sialic acid (SA) receptors that influenza viruses target. The presence and distribution of SA in the mammary glands of pigs, sheep, goats, and alpacas have not been characterized. The current study aimed at the spatial distribution of Sambucus nigra (specific for SA α2,6-Gal receptors) and Maackia amurensis (specific for SA α2,3-Gal receptors) lectin binding on the mammary glands of these production animals. The findings revealed that the mammary glands of pigs, sheep, goats, and alpacas are rich in SA α2,6-Gal receptors, which are crucial for mammalian-adapted IAV binding, while SA α2,3-Gal receptors (specific for avian-adapted IAV) were comparatively less. The receptors distribution in mammary tissue of beef cattle resembled dairy cattle. These findings are significant as they provide insights into the IAV binding ability and potential for virus replication, mutation, and transmission via the milk of other production animals. Funding Sources Internal Funding through Iowa State University, College of Veterinary Medicine Research Advisory Council using Mapes Wildlife Care, Education and Research Endowment funds. Topic Categories Veterinary and Comparative Immunology (VET)