Mastitis is defined as an inflammatory response triggered by bacterial invasion of the mammary gland. It occurs frequently in lactating women and dairy cows. In the dairy industry, mastitis causes substantial economic losses worldwide each year. Bovine mammary epithelial cells serve as the first line of defense against exogenous mammary infections and play a vital role in initiating timely immune responses by recognizing pathogens. Escherichia coli can induce severe acute inflammatory reactions. As a major outer membrane component of Gram-negative bacteria such as Escherichia coli, lipopolysaccharide (LPS) exerts a decisive function in intracellular signal transduction activated by Gram-negative pathogens.

Balb/c mice (male and female, approximately 20 g)
Modeling method: LPS was injected through the mammary duct, and the mastitis model was successfully established 24 hours later.
Evaluation index: HE staining

Breast hematoxylin-eosin (HE) staining