title: Association between endogenous feline leukemia virus loads and exogenous feline leukemia virus infection in domestic cats.
abstract: Recently, we demonstrated that endogenous feline leukemia virus (enFeLV) loads may vary among cats of different populations and that FeLV-infected cats have higher enFeLV loads than uninfected cats. Thus, we hypothesized that enFeLV might influence the pathogenesis and outcome of FeLV infection. No significant difference in the infection outcome (regressive versus progressive infection) was observed between groups of cats with high or low enFeLV loads following FeLV-A challenge. However, cats with high enFeLV loads showed higher viral replication (plasma viral RNA and p27 antigen levels) than cats with low enFeLV loads in the early phase of the infection. The enFeLV transcription level varied at different time points, but no clear-cut pattern was observed. In conclusion, our results demonstrated an association between enFeLV loads and FeLV replication but not outcome of infection. enFeLV should be considered as an important confounder in experimental FeLV infection or vaccination studies.
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
authors.forename: Ravi
authors.initials: R
authors.lastname: Tandon
authors.forename: Valentino
authors.initials: V
authors.lastname: Cattori
authors.forename: Andrea C
authors.initials: AC
authors.lastname: Pepin
authors.forename: Barbara
authors.initials: B
authors.lastname: Riond
authors.forename: Marina L
authors.initials: ML
authors.lastname: Meli
authors.forename: Mike
authors.initials: M
authors.lastname: McDonald
authors.forename: Marcus G
authors.initials: MG
authors.lastname: Doherr
authors.forename: Hans
authors.initials: H
authors.lastname: Lutz
authors.forename: Regina
authors.initials: R
authors.lastname: Hofmann-Lehmann
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000097:blood; D002415:Cats / Q000821:virology*; D020077:Endogenous Retroviruses / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D005256:Leukemia Virus, Feline / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D008297:Male; D011533:Proviruses; D012367:RNA, Viral / Q000235:genetics; D012192:Retroviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D014412:Tumor Virus Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D019562:Viral Load; D014779:Virus Replication
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D012367:RNA, Viral