Abstract:

 Endometritis is one of the three severe diseases in dairy cows, which has serious impact on the development of dairy industry. Gram-positive bacteria are the major pathogens of endometritis. Lipoteichoic acid (LTA) is important component of the cell wall of Gram-positive bacteria. Toll-like receptor 2 (TLR2) is the main receptor of innate immune system, which recognizes pathogenic microorganisms and plays significant role in innate immune reaction. TLR2 has close relationship with endometritis caused by Gram-positive bacteria. In this study, mice were used as model, and uterus infusion was taken with different concentration of LTA. Meanwhile, endometrial epithelia cell culture was stimulated with different concentration of LTA in vitro. Pathological histological changes of endometrial tissue in mice were observed, and expression level of TLR2 and inflammatory cytokine TNF-α, IL-6 in endometrial tissue of mice was analyzed. The results could provide some basis for inflammatory signal pathway mediated by TLR2. The results indicated that infusion of different concentration of LTA led to acute endometritis, and inflammatory cells increased in endometrial tissues. Expression of TLR2, TNF-α, IL-6 mRNA in endometrial tissues and epithelial cells increased significantly after different concentrations of LTA stimulation. The expression level changed depending on LTA concentration. Low concentration led to high level expression, however, high concentration decreased expression level.