title: Cloning and expression of a truncated pigeon circovirus capsid protein suitable for antibody detection in infected pigeons.
abstract: Infections with pigeon circovirus (PiCV) (also termed columbid circovirus) occur in meat and racing pigeons (Columba livia) of all ages and have been reported worldwide. A PiCV infection is associated with immunosuppression and the development of young pigeon disease syndrome. An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of virus-specific serum antibody was developed for research purposes. In the absence of a method to propagate PiCV in cell culture, the assay was based on a recombinant truncated capsid protein (rCapPiCV) produced by overexpression in Escherichia coli. A 6xHis-Tag was fused to the N-terminus of the protein to facilitate purification by metal affinity chromatography and detection by anti-His antibody. PiCV-negative and PiCV-positive control sera were generated by inoculation of pigeons with tissue homogenate containing PiCV, followed by five weekly blood sample collections. Western blotting of the immune serum revealed a specific protein band of approximately 32 kDa, which was absent in the pre-immune sera. Using rCapPiCV as antigen in an indirect ELISA, PiCV-specific antibody was detected in sera of the experimentally PiCV-infected pigeons collected at 1 to 5 weeks post infection. By testing 118 field sera collected in the years 1989, 1991, 1994 and 2008 in the rCapPiCV ELISA, virus-specific antibody was detected in 89 (75%) of the sera. The results obtained demonstrate that the rCapPiCV-based indirect ELISA is able to detect PiCV-specific antibodies in pigeon sera and may be a useful tool for PiCV serodiagnosis.
authors.affiliation: Klinik fur Vogel, University of Munich, Munich, Germany. iris.daum@lah.de
authors.forename: Iris
authors.initials: I
authors.lastname: Daum
authors.forename: Tim
authors.initials: T
authors.lastname: Finsterbusch
authors.forename: Stefan
authors.initials: S
authors.lastname: Härtle
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Göbel
authors.forename: Annette
authors.initials: A
authors.lastname: Mankertz
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Korbel
authors.forename: Christian
authors.initials: C
authors.lastname: Grund