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741.
J. G. McDonald G. T. Kristjansson R. P. Singh P. J. Ellis W. B. McNab 《American Journal of Potato Research》1994,71(3):175-183
In a 1992 survey of potato fields in Canada for the tobacco veinal necrosis strain of potato virus Y (PVYN), initial enzyme-linked immunosorbent assay (ELISA) screening with one monoclonal antibody (MAb 295.5) followed by a second ELISA screening with a panel of several MAbs (4E7, Bioreba, 1F5 and 295.5) was assessed as a means of rapidly identifying positive samples prior to confirmation by bioassay. MAbs 4E7 and Bioreba were used in double antibody sandwich (DAS) ELISA, while MAbs 1F5 and 295.5 were used in triple antibody sandwich (TAS) ELISA. In the second ELISA, MAbs 4E7, 1F5 and Bioreba all enhanced test specificity relative to the retest with MAb 295.5. All the MAbs were found to react, to some degree, with isolates of the common strain of PVY (PVYO), but MAb 4E7 was the most specific widi no cross-reaction being observed at, or above, the signal to noise (S:N) threshold of 4:1. However, this MAb was also the least sensitive. At the S:N threshold of 4:1, its sensitivity was 68%, compared to a sensitivity of close to 100% for the other MAbs 相似文献
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One-day-old gnotobiotic piglets were inoculated intranasally with in vitro passaged porcine circovirus 1 (PCV-1), PCV-2, and porcine parvovirus (PPV) alone or in combination (PCV-1/PCV-2, PCV-1/PPV, and PCV-2/PPV). Piglets were evaluated for 1) the development of porcine postweaning multisystemic wasting syndrome (PMWS), 2) distribution of viral antigens by immunochemistry, and 3) viremia and the presence of viral DNA in nasal and ocular secretions and feces. All single agent-infected piglets and piglets infected with PCV-1/PCV-2 or PCV-1/PPV were clinically asymptomatic. They were transiently viremic and seroconverted to homologous virus(es). At termination of the study on postinfection day (PID) 35, microscopic lesions were restricted to focal inflammatory cell infiltrates in livers and myocardia. One piglet given PCV-1/PPV was PPV viremic for 2 weeks after infection and had lymphangiectasia of the spiral and descending colon associated with granulomatous inflammation. All four PCV-2/PPV-inoculated piglets developed PMWS, characterized by sudden onset of depression and anorexia, icterus, and submucosal edema. One piglet became moribund on PID 27, and the remaining three piglets were euthanatized between PID 27 and PID 30 because of severe disease. Lymph nodes were small and the livers were mottled. Disseminated angiocentric granulomatous inflammation was present in all tissues examined except the brain. Multiple lightly basophilic intracytoplasmic inclusion bodies were identified in macrophages and histiocytes. PCV-2 antigen was widely distributed within macrophages; PPV antigen was sparse. Hepatocellular necrosis and bile retention were prominent. PCV-2 DNA was identified in ocular, fecal, and nasal secretions. Terminal sera contained antibodies to PPV (4/4) and PCV-2 (3/ 4). Production of PMWS in gnotobiotic swine appears to require PCV-2 and additional infectious agents such as PPV for full disease expression in gnotobiotic piglets. 相似文献
745.
PMWS: experimental model and co-infections 总被引:12,自引:0,他引:12
Allan GM McNeilly F Ellis J Krakowka S Botner A McCullough K Nauwynck H Kennedy S Meehan B Charreyre C 《Veterinary microbiology》2004,98(2):165-168
Porcine circovirus type 2 (PCV2) is now recognised as the causal agent of porcine multisystemic wasting syndrome (PMWS), an economically important wasting disease of young pigs [J. Vet. Diagn. Invest. 12 (2000) 3]. Gross lesions of PMWS include generalised lymphadenopathy, hepatitis, nephritis and pneumonia and typical histological lesions include lymphocytic depletion and multinucleated giant cell formation in lymph nodes, degeneration and necrosis of hepatocytes, and multifocal lymphohistocytic interstitial pneumonia.This communication will review the results of experimental infections of gnotobiotic (GN), colostrum-deprived (CD) and colostrum-fed (CF) pigs within our group, and elsewhere, with PCV2 and the conclusions that can be drawn from this work. 相似文献