Description
Background: Udder infections with environmental pathogens like Escherichia coli are a serious problem for the diary industry. Reduction of incidence and severity of mastitis is desirable and mild priming of the immune system either through vaccination or with low doses of an immune stimulant like lipopolysaccharide LPS was previously found to dampen detrimental effects of a subsequent infection. Monocytes / macrophages are known to develop tolerance to the endotoxin (ET) LPS as adaptation strategy to prevent exuberant inflammation. We have recently observed that application of 1 g of LPS/udder quarter effectively protects the cow for several days from an experimentally elicited mastitis. We have modelled this process in primary cultures of Mammary Epithelial Cells (MEC) from the cow. This is by far the most abundant cell type in the udder coming into contact with invading pathogens and little is known about the role of MEC in establishing ET in the udder.