Peripheral immunophenotype and viral promoter variants during the asymptomatic phase of feline immunodeficiency virus infection.

Abstract

Feline immunodeficiency virus (FIV)-infected cats enter a clinically asymptomatic phase during chronic infection. Despite the lack of overt clinical disease, the asymptomatic phase is characterized by persistent immunologic impairment. In the peripheral blood obtained from cats experimentally infected with FIV-C for approximately 5 years, we identified a persistent inversion of the CD4/CD8 ratio. We cloned and sequenced the FIV-C long terminal repeat containing the viral promoter from cells infected with the inoculating virus and from in vivo-derived peripheral blood mononuclear cells and CD4 T cells isolated at multiple time points throughout the asymptomatic phase. Relative to the inoculating virus, viral sequences amplified from cells isolated from all of the infected animals demonstrated multiple single nucleotide mutations and a short deletion within the viral U3, R and U5 regions. A transcriptionally inactivating proviral mutation in the U3 promoter AP-1 site was identified at multiple time points from all of the infected animals but not within cell-associated viral RNA. In contrast, no mutations were identified within the sequence of the viral dUTPase gene amplified from PBMC isolated at approximately 5 years post-infection relative to the inoculating sequence. The possible implications of these mutations to viral pathogenesis are discussed.

• Authors: B Murphy, C Hillman, S McDonnel
• Journal: Virus research (Virus Res) Vol. 179 Pg. 34-43 (Jan 22 2014) ISSN: 1872-7492 [Electronic] Netherlands
• PMID: 24291288 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier B.V. All rights reserved.

Topics

• Animals
• Asymptomatic Diseases
• CD4-Positive T-Lymphocytes (virology)
• Cats
• Disease Progression
• Feline Acquired Immunodeficiency Syndrome (immunology, pathology, virology)
• Immunodeficiency Virus, Feline (genetics, physiology)
• Promoter Regions, Genetic
• Proviruses (genetics, physiology)