- I.A. Gardner (1)
- J. Gavalchin (1)
- J.F.T. Griffin (1)
- E. Gruys (1)
- B. Harris (1)
- A. Hoek van (1)
- A.D. Hughes (1)
- A. Koets (1)
- S. Liggett (1)
- J.E. Lombard (1)
- C.G. Mackintosh (1)
- F. Mil van (1)
- K. Muller (1)
- S.S. Nielsen (1)
- V. Rutten (1)
- D.R. Smith (1)
- S. Sreevatsan (1)
- R. Sweeney (1)
- R.J. Whittington (1)
Consensus based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants.
Gardner, I.A. ; Nielsen, S.S. ; Whittington, R.J. ; Collins, M.T. ; Bakker, D. ; Harris, B. ; Sreevatsan, S. ; Lombard, J.E. ; Sweeney, R. ; Smith, D.R. ; Gavalchin, J. ; Eda, S. - \ 2011
Preventive Veterinary Medicine 101 (2011)1-2. - ISSN 0167-5877 - p. 18 - 34.
avium subsp-paratuberculosis - linked-immunosorbent-assay - pooled fecal culture - real-time pcr - mycobacterium-avium - johnes-disease - dairy-cattle - ovine paratuberculosis - bovine-paratuberculosis - serological tests
The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and sampling designs, and the widespread lack of an ante-mortem reference standard with high sensitivity and specificity. The objective of the present study was to develop a modified version of STARD relevant to paratuberculosis (Johne's disease) in ruminants. Examples and elaborations for each of the 25 items were developed by a panel of experts using a consensus-based approach to explain the items and underlying concepts. The new guidelines, termed STRADAS-paraTB (Standards for Reporting of Animal Diagnostic Accuracy Studies for paratuberculosis), should facilitate improved quality of reporting of the design, conduct and results of paratuberculosis test accuracy studies which were identified as "poor" in a review published in 2008 in Veterinary Microbiology
Efficacy of novel lipid-formulated whole bacterial cell vaccines against Mycobacterium avium subsp paratuberculosis in sheep
Griffin, J.F.T. ; Hughes, A.D. ; Liggett, S. ; Farquhar, P.A. ; Mackintosh, C.G. ; Bakker, D. - \ 2009
Vaccine 27 (2009)6. - ISSN 0264-410X - p. 911 - 918.
johnes-disease - oral vaccination - bovis bcg - ovine paratuberculosis - pulmonary tuberculosis - brushtail possums - calmette-guerin - resistance - infection - protection
Mycobacterium avium subsp. paratuberculosis [MAP], the Causative agent of enteric Johne's disease, incurs significant economic losses to the livestock industry. Prophylactic vaccination can be employed as a control means, however mineral oil-based vaccines Currently in practice have limited efficacy, produce strong antibody responses that confound serological diagnostic testing, and cause severe injection site reactions. In the present study, the safety and efficacy of a commercial mineral oil-adjuvanted vaccine (Gudair (TM)) was compared with novel parenteral-route vaccines in sheep: these comprised live or heat-killed (HK) whole cell preparations of MAP strain 316F, formulated into a food-grade lipid vaccine delivery matrix. Subcutaneous administration of lipid-formulated live or I HK 316F-induced significantly fewer adverse injection site reactions than Gudair (TM); adverse injection site reactions were eliminated altogether by intraperitoneal (i.p.) injection of lipid-formulated live 316F Injections of lipid-formulated 316F-induced significant peripheral blood cell-mediated immune (CMI) responses in the absence of antibody, while Gudair (TM)-induced strong antibody and CMI reactivity. Vaccinated and non-vaccinated control sheep were challenged via oral inoculation of a virulent MAP isolate, and disease progress was monitored for 16 months, followed by necropsy. All vaccine regimes reduced the overall pathological grading of biopsied intestinal tract (IT) tissues; among these, only Gudair (TM) promoted a significant reduction in the incidence of histopathological IT lesions, while only i.p. injection of lipid-formulated live 316F significantly reduced the incidence of gross IT lesions. All lipid-formulated vaccines (but not Gudair (TM)) significantly reduced the incidence of bacteriological culture-confirmed MAP infection. This study identifies a new vaccination strategy against Johne's disease in sheep using conventional MAP vaccine strains formulated in a metabolisable lipid delivery matrix. (C) 2008 Published by Elsevier Ltd.
Progressive bovine paratuberculosis is associated with local loss of CD4(+) T cells, increased frequency of gamma delta T cells, and related changes in T-cell function
Koets, A. ; Rutten, V. ; Hoek, A. van; Mil, F. van; Muller, K. ; Bakker, D. ; Gruys, E. ; Eden, W. van - \ 2002
Infection and Immunity 70 (2002)7. - ISSN 0019-9567 - p. 3856 - 3864.
blood mononuclear-cells - lymphoblast proliferative capacity - johnes-disease - monoclonal-antibodies - mycobacterium-paratuberculosis - para-tuberculosis - lymphocytes-t - ovine paratuberculosis - lymph-node - alpha-beta
Bovine paratuberculosis is caused by the infection of young calves with Mycobacterium avium subsp. paratuberculosis, resulting in a chronic granulomatous infection of predominantly the ileum. After an incubation period of 2 to 5 years, the disease becomes progressive in some of the chronically infected, but asymptomatic cows. This results in a protein-losing enteropathy that will ultimately be fatal. A loss of cell-mediated immune responses in symptomatic animals has been described, but no information is available concerning immune reactivity in the intestine. We sought to investigate putative disease status-associated lymphocyte subset distributions and antigen-specific functional characteristics of mononuclear cells isolated from blood, gut-associated lymphoid tissue, and the intestinal walls of 22 cows in different stages of disease and in control animals. The results demonstrated a significant decrease in CD4+ T-cell frequency and a significant increase in TcR1-N12+ T-cell frequency in ileum lamina propria lymphocytes of symptomatic animals compared to the asymptomatic shedders. Immunohistology revealed that there was also an absolute decrease in the number of CD4+ T cells in sections of the lesional ileum. Our findings also indicated that both peripheral and intestinal cell-mediated responses are decreased in symptomatic animals compared to asymptomatic animals. We conclude that the decrease in cell-mediated responses is likely related to a loss of antigen-specific CD4+ T cells, which is most prominent in the lesional ileum from symptomatic animals, thus contributing to the progressive nature of bovine paratuberculosis