| 3. |
- Pujato, N., et al.
(författare)
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Evaluation of the humoral immune response to a multicomponent recombinant vaccine against S-aureus in healthy pregnant heifers
- 2018
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Ingår i: The Veterinary Journal. - : Elsevier. - 1090-0233 .- 1532-2971. ; 235, s. 47-53
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Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus aureus is a worldwide pathogen that causes mastitis in dairy herds. Shortcomings in control programs have encouraged the development of vaccines against this pathogen. This study evaluated the vaccine candidate VacR, which included recombinant S. aureus protein clumping factor A (rClf), fibronectin binding protein A (rFnBP) and hemolysin beta (rBt), formulated with a novel immune-stimulating complex. Comparisons were made between healthy pregnant heifers that received either VacR (n = 8; VacR group) or phosphate buffered saline (PBS) plus adjuvant (control group) SC in the supramammary lymph node area on days 45 and 15 before the expected calving date. Blood and foremilk samples were collected from 7 to 60 days post-calving. After calving, heifers in the VacR group produced higher total IgG (IgG(total)) titers against each component, in both serum (rBt, 3.4 x 10(5); rClf, 3.1 x 10(5); rFnBP, 2.3 x 10(5)) and milk (rBt, 2.6 x 10(4); rClf, 1.3 x 10(4); rFnBP, 1.1 x 10(4)), than control heifers (P < 0.0001). There were increased concentrations of IgG(1), and IgG(2) in VacR group (P < 0.05), in both serum and milk. Humoral responses remained high throughout the period most susceptible to intramammary infections (P < 0.01). Antibodies produced against S. aureus rClf and rFnBP reduced bacterial adherence to fibronectin and fibrinogen by 73% and 67%, respectively (P < 0.001). Milk antibodies against these adhesins inhibited S. aureus invasion of a mammary epithelial cell line (MAC-T), resulting in 15.7% of bacteria internalized (P < 0.0001). There was an approximately 6-fold reduction in the hemolysis titer for the native hemolysin in the VacR group compared to the control group (P < 0.0001) and a significantly increase in the proportion of positive neutrophils (VacR, 29.7%; PBS, 13.1%) and the mean fluorescent index (VacR, 217.4; PBS, 152.6; P < 0.01) in the VacR group. The results suggest that VacR is a valuable vaccine candidate against S. aureus infections, and merits further field trials and experimental challenges. (C) 2018 Elsevier Ltd. All rights reserved.
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| 4. |
- Camussone, Cecilia M., et al.
(författare)
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Immune response of heifers against a Staphylococcus aureus CP5 whole cell and lysate vaccine formulated with ISCOM Matrix adjuvant
- 2014
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Ingår i: Research in Veterinary Science. - : Elsevier BV. - 0034-5288 .- 1532-2661. ; 96:1, s. 86-94
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Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus aureus is the most frequently isolated pathogen from bovine intramammary infections worldwide. Commercially available vaccines for mastitis control are composed either of S. aureus lysates or whole-cells formulated with traditional adjuvants. We recently showed the ability of a S. aureus CP5 whole-cell vaccine adjuvanted with ISCOM Matrix to increase specific antibodies production in blood and milk, improving opsonic capacity, compared with the same vaccine formulated with Al(OH)(3). However, there is no information about the use of ISCOM Matrix for the formulation of bacterial lysates. The aim of this study was to characterize the innate and humoral immune responses induced by a S. aureus CP5 whole-cell or lysate vaccine, formulated with ISCOM Matrix after immunization of pregnant heifers. Both immunogens stimulated strong humoral immune responses in blood and milk, raising antibodies that increased opsonic capacity. Lysate formulation generated a higher and longer lasting antibody titer and stimulated a higher expression of regulatory and pro-inflammatory cytokines compared with the whole-cell vaccine. (C) 2013 Elsevier Ltd. All rights reserved.
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