ARS | Publication request: Compromised neutrophil function and severe bovine E.coli mastitis: is C5a the missing link?

Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Literature Review
Publication Acceptance Date: July 9, 2012
Publication Date: July 16, 2012
Repository URL: http://handle.nal.usda.gov/10113/56532
Citation: Stevens, M.G., Speigeleer, B., Peelmean, L., Boulougouris, X., Capuco, A.V., Burvenich, C. 2012. Compromised neutrophil function and severe bovine E.coli mastitis: is C5a the missing link?. Veterinary Immunology and Immunopathology. 149:151-156.

Technical Abstract: Around the periparturient period and during early lactation dairy cows have an elevated risk for clinical mastitis. The severity of Gram-negative infections during these periods has been correlated with reduced neutrophil functions. In this review we focus on the potential role of C5a in the development of severe inflammatory responses in immune compromised animals. Substantial evidence has been published that high concentrations of C5a have an immune suppressive effect on neutrophils. We present a hypothesis about C5a dependent immune suppression of neutrophils and the subsequent development of a severe immune response. In addition, crosstalk between C5a signalling and TLR4 signalling could result in a positive feedback mechanism which may be involved in the pathogenesis of a severe mastitis response. Finally, interference with the C5a signalling pathway could be an important strategy in the treatment of severe gram-negative mastitis in dairy cattle.