Characterization of immune response in Staphylococcus aureus chronically infected bovine mammary glands during active involution

• Published in: Comparative immunology, microbiology and infectious diseases Vol. 54; pp. 51 - 60
• Main Authors: Andreotti, Carolina S., Baravalle, Celina, Sacco, Sofía C., Lovato, Melisa, Pereyra, Elizabet A.L., Renna, María S., Ortega, Hugo H., Calvinho, Luis F., Dallard, Bibiana E.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2017; Elsevier Science Ltd
• Subjects: Active control; Adaptive Immunity; Animals; Antibodies, Bacterial - immunology; Antibody Specificity; Cattle; Chronic infection; Cytokines; Dairy cattle; Female; Immune response; Immune system; Immunity, Innate; Immunohistochemistry; Interleukin 17; Interleukin-17 - analysis; Interleukin-1alpha - analysis; Involution; Lactation; Lactoferrin; Lymphocytes; Lymphocytes - immunology; Lymphocytes B; Lymphocytes T; Macrophages; Macrophages - immunology; Mammary gland; Mammary glands; Mammary Glands, Animal - cytology; Mammary Glands, Animal - immunology; Mammary Glands, Animal - microbiology; Mastitis; Mastitis, Bovine - immunology; Mastitis, Bovine - microbiology; Milking; Monocytes; Protein expression; Proteins; Staphylococcal Infections - immunology; Staphylococcal Infections - veterinary; Staphylococcus aureus; Staphylococcus aureus - immunology; Staphylococcus infections; TLR2 protein; TLR4 protein; Toll-Like Receptor 2 - analysis; Toll-like receptors; Tumor Necrosis Factor-alpha - analysis; Tumor necrosis factor-α; Mastitis; Involution; Immune response; Staphylococcus aureus
• ISSN: 0147-9571; 1878-1667
• DOI: 10.1016/j.cimid.2017.08.005

•Protein expression of TLR2 and 4 was increased in chronically S. aureus-infected mammary glands.•TNF-α, IL-1α and IL-17 protein expression were increased in chronically S. aureus-infected glands.•Number of macrophages, T and B cells were increased in chronically S. aureus-infected glands.•Chronic S. aureus IMI induced a sustained and exacerbated immune response during involution. The aim of this study was to characterize the immune response in Staphylococcus aureus chronically infected bovine mammary glands during active involution. Twenty-one Holstein non-pregnant cows in late lactation either uninfected or with chronic naturally acquired S. aureus intramammary infections (IMI) were included in this study. Cows were slaughtered at 7, 14 and 21 d after cessation of milking and samples for immunohistochemical analysis were taken. Protein expression of toll-like receptor 2 (TLR2) and TLR4 was significantly higher in S. aureus-infected quarters than in uninfected controls at the three involution stages studied. Protein expression of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1α and IL-17 was significantly affected by IMI; being higher in S. aureus-infected than uninfected quarters during all evaluated stages. In S. aureus-infected and uninfected quarters protein expression of lactoferrin increased from day 7–14 of involution, decreasing significantly to day 21 in mammary quarters with chronic infections. The number of monocytes-macrophages was significantly higher in S. aureus-infected than in uninfected control quarters at 7 and 21 d of involution. The number of T lymphocytes was significantly higher in S. aureus-infected than in uninfected quarters at 7 and 14 d of involution while the number of B lymphocytes was significantly higher in S. aureus-infected than in uninfected quarters during all evaluated stages, showing a progressive increase as involution advanced. These results demonstrated a sustained and exacerbated innate and adaptive immune response during chronic S. aureus IMI, playing a critical role in the infection control during active involution.