Methylation of selected CpG islands involved in the transcription of myeloperoxidase and superoxide dismutase 2 in neutrophils of periparturient and mid-lactation cows.

It is generally accepted that intracellular killing of microorganisms by production of reactive oxygen species (ROS) in the phagosome of the neutrophil is an important arm of innate defense. High-producing dairy cows are prone to periparturient metabolic and infectious diseases. Both myeloperoxidase (MPO) activity and ROS production decrease the day of parturition.

Reactive oxygen species generation by bovine blood neutrophils with different CXCR1 (IL8RA) genotype following Interleukin-8 incubation.

Background: Associations between polymorphisms in the bovine CXCR1 gene, encoding the chemokine (C-X-C motif) receptor 1 (IL8RA), and neutrophil traits and mastitis have been described. In the present study, blood neutrophils were isolated from 20 early lactating heifers with different CXCR1 genotype at position 735 or 980. The cells were incubated with different concentrations of recombinant bovine IL-8 (rbIL-8) for 2 or 6 h and stimulated with phorbol 12-myristate 13-acetate (PMA) or opsonized zymosan particles (OZP).

Compromised neutrophil function and bovine E. coli mastitis: is C5a the missing link?

During early lactation, dairy cow are prone to developing severe mastitis in responses to intramammary Escherichia coli infections. These severe inflammatory responses have been correlated with reduced neutrophil function during the periparturient period. However, the causative mechanism of neutrophil dysfunction has not been elucidated.