Unravelling proteomic changes of primary bovine endometrial epithelial cells to lipopolysaccharide and lipoteichoic acid bacterial ligand stimulation.

Uterine health is essential for the reproductive success of dairy cows because endometritis is an important cause of infertility. Infections, particularly those caused by bacterial pathogens, lead to inflammatory responses in the uterus and economics losses to the dairy industry. This study aimed to investigate the proteomic alterations in bovine endometrial epithelial cells (bEECs) in response to bacterial ligands, specifically lipoteichoic acid (LTA) and lipopolysaccharide (LPS), and to identify potential biomarkers for the early diagnosis of endometritis. Gel-free mass spectrometry analysis revealed significant differential protein expression in bEECs stimulated with LTA and LPS compared to untreated control cells. Key proteins such as CXCL6 and Serum Amyloid A (SAA) were upregulated by 3.5-fold and 2.8-fold, respectively, in the LPS treatment group. Additionally, proteins like CCAAT/enhancer-binding protein β and oxidized low-density lipoprotein were significantly elevated by 2.2-fold and 1.9-fold in the LPS/LTA treatment group. This study underscores the importance of proteomic changes in bEECs in mediating immune responses to bacterial infection. The identified proteins, including CXCL6, SAA, and CCAAT/enhancer-binding protein β, play key roles in endometrial inflammation, tissue remodeling and repair, suggesting their potential as candidate biomarkers for the early detection of endometritis, that warrant further targeted validation. These findings could lead to more effective management strategies for improving reproductive health and fertility in dairy cows.