Vet. Res. 35 (2004) 189-197
DOI: 10.1051/vetres:2004003

Detection of bovine respiratory syncytial virus in experimentally infected balb/c mice

Renata Servan Almeida, Helena Gallicchio Domingues, Lia Treptow Coswig, Regina Celia Freitas D'Arce, Rodrigo Franco de Carvalho and Clarice Weis Arns

Laboratório de Virologia Animal, Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, 13081-970 Campinas, SP, Brazil
(Received 4 March 2003; accepted 18 September 2003)

Abstract - The present study used an RT-nested-PCR and an immunohistochemistry assay to detect bovine respiratory syncytial virus in tissues from experimentally infected balb/c mice. As a first step, Chicken Embryo Related (CER) cell monolayers infected with the BRSV-25-BR strain isolated in Brazil were used for antigen production. Then, the infected lung and tracheal tissues of female balb/c mice were collected on 3, 5, 7 and 10 days post-infection and submitted to both techniques. Primers specific to F and G genes that amplify fragments of 481 bp and 371 bp, respectively, were used. The BRSV detection was not successful in all of the animals tested. The genomic fragment of the G gene from the organs of some infected mice on all analyzed post-infection days was amplified. However, in the RT-nested-PCR corresponding to the F gene, it was not possible to observe any amplified fragment. This was probably due to the higher sensitivity of the developed technique to amplify the fragment corresponding to the G gene compared to the F gene. Moreover, only three of the lungs collected five days post-infection were positive by immunohistochemistry. To the author's knowledge, this is the first study reporting bovine respiratory syncytial virus detection in balb/c mice after experimental inoculation.

Key words: bovine respiratory syncytial virus / RT-nested-PCR / immunohistochemistry / mice / experimental infection

Corresponding author: Clarice Weis Arns arns@obelix.unicamp.br

© INRA, EDP Sciences 2004