title: Effect of intramammary infusion of recombinant bovine GM-CSF and IL-8 on CMT score, somatic cell count, and milk mononuclear cell populations in Holstein cows with Staphylococcus aureus subclinical mastitis.
abstract: The effect of intramammary infusion of recombinant bovine granulocyte-macrophage colony-stimulating factor (rbGM-CSF) and interleukin-8 (rbIL-8) on mononuclear cell populations in quarters, somatic cell count (SCC) and the California Mastitis Test (CMT) score were investigated. From the selected cows with naturally occurring Staphylococcus aureus subclinical mastitis, one quarter of each cow were selected for the infusions of rbGM-CSF (400 μg/5 mL/quarter, n = 9), rbIL-8 (1 mg/5 mL/quarter, n = 9), and phosphate-buffered saline (5 mL/quarter, n = 7). The CMT score of both cytokines post infusion temporarily increased between days 0 and 1 and significantly decreased between days 7 and 14 compared to the preinfusion level. The SCC on day 14 after infusions of rbGM-CSF tended to be lower than that of the control group. The percentage of CD14+ cells increased on days 1 and 2 post infusion of rbGM-CSF. The percentage of CD4+ and CD8+ cells also increased on days 2 and 3, suggesting that the infusion of rbGM-CSF enhanced cellular immunity in the mammary gland. In contrast, the percentage of CD14+ cells decreased on days 0.25 and 1 post infusion of rbIL-8. No significant changes in the percentages of CD4+ and CD8+ cells in milk after infusion of rbIL-8 were evident during the experimental period, which suggested that rbIL-8 had little effect on the function of T cells in the mammary gland. These results indicated that rbGM-CSF and rbIL-8 decreased the CMT score by a different mechanism and may have a potential as therapeutic agents for subclinical mastitis.
authors.affiliation: Hokkaido Research Station, National Institute of Animal Health, NARO, 4 Hitsujigaoka, Toyohira, Sapporo, Hokkaido, 062-0045, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kiku
authors.affiliation: National Institute of Animal Health, NARO, Tsukuba, Ibaraki, 305-0856, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Ozawa
authors.affiliation: National Institute of Animal Health, NARO, Tsukuba, Ibaraki, 305-0856, Japan.|Japan Association for Techno-innovation in Agriculture, Forestry and Fisheries, Tsukuba, Ibaraki, 305-8601, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: NARO Institute of Livestock and Grassland Science, Tsukuba, Ibaraki, 305-0901, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Kushibiki
authors.affiliation: National Institute of Animal Health, NARO, Tsukuba, Ibaraki, 305-0856, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Inumaru
authors.affiliation: NARO Institute of Livestock and Grassland Science, Tsukuba, Ibaraki, 305-0901, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shingu
authors.affiliation: Hokkaido Research Station, National Institute of Animal Health, NARO, 4 Hitsujigaoka, Toyohira, Sapporo, Hokkaido, 062-0045, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Nagasawa
authors.affiliation: Hokkaido Research Station, National Institute of Animal Health, NARO, 4 Hitsujigaoka, Toyohira, Sapporo, Hokkaido, 062-0045, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Watanabe
authors.affiliation: Hokkaido Research Station, National Institute of Animal Health, NARO, 4 Hitsujigaoka, Toyohira, Sapporo, Hokkaido, 062-0045, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Hata
authors.affiliation: Hokkaido Research Station, National Institute of Animal Health, NARO, 4 Hitsujigaoka, Toyohira, Sapporo, Hokkaido, 062-0045, Japan. hayatomo@affrc.go.jp.
authors.forename: Tomohito
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D000818:Animals; D058345:Asymptomatic Infections; D002417:Cattle; D002452:Cell Count / Q000662:veterinary; D005260:Female; D005434:Flow Cytometry; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000008:administration & dosage / Q000627:therapeutic use*; D016209:Interleukin-8 / Q000008:administration & dosage / Q000627:therapeutic use*; D007958:Leukocyte Count / Q000662:veterinary; D008321:Mammary Glands, Animal / Q000382:microbiology; D008414:Mastitis, Bovine / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D011994:Recombinant Proteins / Q000627:therapeutic use; D013203:Staphylococcal Infections / Q000382:microbiology / Q000662:veterinary*
chemical_list: D016209:Interleukin-8; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor
keywords: Bovine; CMT; GM-CSF; IL-8; Mastitis; Milk mononuclear cell population