RNA-seq analysis of different inflammatory reactions induced by lipopolysaccharide and lipoteichoic acid in bovine mammary epithelial cells

Lipopolysaccharide (LPS) and lipoteichoic acid (LTA) are key virulence factors of Escherichia coli and Staphylococcus aureus respectively, and both of them could cause inflammatory reaction in bovine mammary glands. In this study, we used bovine mammary epithelial cells (BMECs) as pattern recognition receptors and stimulated them with LPS or LTA to investigate the global transcriptional response variations of BMECs to these two different virulent factors through RNA-Seq analysis. We found 100 differentially expressed genes (DEGs) with 95 up-regulated and 5 down-regulated genes in LPS-treated group, whereas 24 DEGs with 12 up-regulated and 12 down-regulated genes in LTA-treated group compared to control. Although the number and expression changes of DEGs are significantly different between LPS vs Control and LTA vs Control, KEGG pathway enrichment analysis showed the majorities of DEGs in each pair were enriched on cytokine-cytokine receptor interaction, NF-kappa B signaling pathway, and NOD-like receptor signaling pathway, especially cytokines and chemokines. These results provided a comprehensive analysis of gene expression profiles elicited by LPS and LTA in BMECs, contributing to the understanding of early pathogen-host interactions during intramammary infections.