Widespread expression of avian and human influenza A virus receptors in bovine mammary glands
Researchers from the University of Copenhagen in Denmark and St. Jude's Children's Research Hospital in Memphis, Tennessee, analyzed the expression of avian and human influenza A virus receptors in the bovine mammary gland in a new study published in bioRxiv. This study sheds light on the presence of sialic acid receptors in cattle, which may have implications for host tropism and virus transmission. The widespread expression of sialic acid receptors in the bovine mammary gland has significant implications for influenza A virus (IAV) infection in cattle. This finding suggests that the mammary gland could serve as a potential site for viral replication and shedding, leading to the presence of the virus in milk from infected cows.
The co-expression of both human and avian receptors in the mammary glands indicates susceptibility to viruses of both swine/human and avian origin, raising concerns about zoonotic transmission and the potential for cattle to act as a mixing vessel for novel IAV generation. Furthermore, the high levels of H5N1 virus reported in infected bovine milk may be attributed to local viral replication in the mammary gland due to the high affinity of the virus for the receptors present.
