The cytokine markers in Staphylococcus aureus mastitis of bovine mammary gland

TaqMan® real time PCR was used to study the transcriptional activity of the bovine IL-2, IL-6, IL-12p40, IFN-γ, TNF-α and granulocyte-monocyte colony stimulating factor of whole milk cells in bovine mammary gland experimentally infected with Staphylococcus aureus. Cytokine transcriptional activity was monitored at 7, 24 and 32 h Post-infection (Pi). IL-12 and TNF-α levels were significantly elevated at 24 h Pi followed by sharp decrease at 32 h pi. IL-2 level was decreased at 32 h pi. IL-12 and IFN-γ showed a significant interaction at 24 h pi. The significant elevations of the IL-12 and TNF-α transcriptional level most likely indicate their important role in regulation of the immune responses of bovine mammary gland in S. aureus infection. Depression of IL-2 could reflect the suppressive nature of the S. aureus mastitis.