Inflammatory effect of cleaved bovine lactoferrin by elastase on staphylococcal mastitis

Area of Science:

• Veterinary Immunology
• Biochemistry
• Molecular Biology

Background:

• Staphylococcal mastitis is a significant challenge in bovine health.
• Bovine lactoferrin (bLf) is an important immune-modulating protein in milk.
• The role of bLf modifications during mastitis requires further elucidation.

Purpose of the Study:

• To investigate the effect of elastase on bLf during bovine staphylococcal mastitis.
• To determine the inflammatory potential of elastase-modified bLf.

Main Methods:

• Detection of elastase activity and Concanavalin A (Con A) low-affinity bLf in mammary secretions.
• Treatment of bLf with elastase and analysis via Con A two-dimensional immunoelectrophoresis.
• Confirmation and synthesis of specific bLf peptides.
• Assessment of inflammatory gene expression (IL-6, TNFα, IL-8, MCP-1) in bovine mammary epithelial cells.

Main Results:

• Elastase activity and low Con A affinity bLf correlated with clinical mastitis severity.
• Elastase treatment of bLf produced smaller molecules with similar immunoelectrophoresis profiles to mastitic bLf.
• Four common bLf peptides were identified in elastase-treated and mastitic bLf.
• Low Con A affinity bLf and a specific synthetic peptide (GQRDLLFKDSAL) induced strong expression of inflammatory genes.

Conclusions:

• Elastase cleaves bLf in mastitic mammary glands, altering its physical properties and function.
• Elastase-induced low Con A affinity bLf, including the GQRDLLFKDSAL peptide, contributes to the inflammatory process in staphylococcal mastitis.