Project description:The 2024 outbreak of highly pathogenic avian influenza virus (HPAIV) H5N1 in U.S. dairy cattle presented an unprecedented scenario where the virus infected bovine mammary glands and was detected in milk, raising serious concerns for public health and the dairy industry. Unlike previously described subclinical influenza A virus (IAV) infections in cattle, H5N1 infection induced severe clinical symptoms, including respiratory distress, mastitis, and abnormal milk production. To understand the host immune responses and changes particularly in the mammary gland, we performed scRNA-seq analysis on bovine milk somatic cells (bMSC) in-vitro infected with H5N1 isolate from dairy farm. We identified ten distinct cell clusters and observed a shift toward type-2 immune responses, characterized by T-cells expressing IL13 and GATA3, and three different subtypes of epithelial cells based on expression of genes associated with milk production. Our study revealed temporal dynamics in cytokine expression, with a rapid decline in luminal epithelial cells and an increase in macrophages and dendritic cells, suggesting a role in increased antigen presentation. These findings indicate that bovine H5N1 infection triggers complex immune responses involving both pro-inflammatory and regulatory pathways. This research fills a critical gap in understanding the immune responses of bovine mammary glands to H5N1 infection and highlights the need for further investigation into therapeutic strategies for managing such outbreaks.
2025-04-08 | GSE294077 | GEO
Project description:H5N1 clade 2.3.4.4b experimental infection of lactating cows
Project description:The pathogenesis of avian influenza A H5N1 virus in human has not been clearly elucidated. There have been increasing evidence suggesting a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. However, the role of aberrant innate immune response in human lungs infected by avian influenza H5N1 virus has not been explored and direct evidence for inappropriate innate responses in lungs of avian influenza H5N1 virus infected patients is lacking.
Project description:Analysis of lung samples from mice infected with a severe H5N1 influenza virus (VN/1203/04/H5N1) or a mild H1N1 influenza virus (NYMC-X-179A) on day 3 and day 5 post-infection. Uninfected controls were used for comparison.
Project description:The emergence of influenza A viruses (IAV) from zoonotic reservoirs poses a great threat to human health. As seasonal vaccines are ineffective against zoonotic strains, and newly transmitted viruses can quickly acquire drug resistance, there remains a need for host- directed therapeutics against IAV. Here, we performed a genome-scale CRISPR/Cas9 knockout screen in human lung epithelial cells with a human isolate of an avian H5N1 strain. Several genes involved in sialic acid biosynthesis and related glycosylation pathways were highly enriched post-H5N1 selection, including SLC35A1, a sialic acid transporter essential for IAV receptor expression and thus viral entry. Importantly, we have identified capicua (CIC) as a negative regulator of cell intrinsic immunity, as loss of CIC resulted in heightened antiviral responses and restricted replication of multiple viruses. Therefore, our study demonstrates that the CRISPR/Cas9 system can be utilized for the discovery of host factors critical for the replication of intracellular pathogens.
Project description:Human disease caused by highly pathogenic avian influenza (HPAI) H5N1 can lead to a rapidly progressive viral pneumonia leading to acute respiratory distress syndrome. There is increasing evidence suggests a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. The key target cells for the virus in the lung are the alveolar epithelium and alveolar macrophages, and previous data has shown that compared to seasonal human influenza viruses, equivalent infecting doses of H5N1 viruses markedly up-regulate pro-inflammatory cytokines in both primary cell types in vitro. The dysregulation of H5N1-induced host responses is therefore important for understanding the viral pathogenesis. We used microarrays to analyze and compare the gene expression profiles in primary human macrophages after influenza A virus infection.