Previous Article | Next Article ![]()
Clinical and Vaccine Immunology, October 2007, p. 1274-1278, Vol. 14, No. 10
1071-412X/07/$08.00+0 doi:10.1128/CVI.00095-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, Washington 99164-6630,1 Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164-7730,2 U.S. Sheep Experiment Station, Agricultural Research Service, U.S. Department of Agriculture, Dubois, Idaho 834233
Received 26 February 2007/ Returned for modification 22 April 2007/ Accepted 9 August 2007
Ovine progressive pneumonia virus (OPPV) infects at least one sheep in 81% of U.S. sheep flocks, as determined by serology, and can cause viral mastitis, arthritis, dyspnea, and cachexia. Diagnostic tests that quantify OPPV proviral load in peripheral blood leukocytes (PBL) provide an additional method for identification of infected sheep and may help to further understanding of the pathogenesis of OPPV-induced disease. In this study, we compared a new OPPV real-time quantitative PCR (qPCR) assay specific for the transmembrane region of the envelope gene (tm) with a competitive inhibition enzyme-linked immunosorbent assay (cELISA) using 396 PBL samples and sera from Idaho sheep. The OPPV qPCR had a positive concordance of 96.2% ± 2.3% and a negative concordance of 97.7% ± 2.5% compared to the cELISA, with a kappa value of 0.93, indicating excellent agreement between the two tests. In addition, the presence of tm in the three OPPV qPCR-positive and cELISA-negative sheep and in 15 sheep with different OPPV proviral loads was confirmed by cloning and sequencing. These data indicate that the OPPV qPCR may be used as a supplemental diagnostic tool for OPPV infection and for measurement of viral load in PBLs of infected sheep.
Published ahead of print on 15 August 2007.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»