Previous Article | Next Article ![]()
J. Virol., Sep 1997, 6407-6415, Vol 71, No. 9
BJ Willett, L Picard, MJ Hosie, JD Turner, K Adema and PR Clapham
Feline immunodeficiency virus (FIV) induces a disease state in the domestic
cat that is similar to AIDS in human immunodeficiency virus (HIV)-infected
individuals. As with HIV, FIV can be divided into primary and cell
culture-adapted isolates. Adaptation of FIV to replicate and form syncytia
in the Crandell feline kidney (CrFK) cell line is accompanied by an
increase in the net charge of the V3 loop of the envelope glycoprotein,
mirroring the changes observed in the V3 loop of HIV gp120 with the switch
from a non-syncytium-inducing phenotype to a syncytium-inducing phenotype.
These data suggest a common mechanism of infection with FIV and HIV. In
this study, we demonstrate that cell culture-adapted strains of FIV are
able to use the alpha-chemokine receptor CXCR4 for cell fusion. Following
ectopic expression of human CXCR4 on nonpermissive human cells, the cells
are able to fuse with FIV-infected feline cells. Moreover, fusion between
FIV-infected feline cells and CXCR4-transfected human cells is inhibited by
both anti-CXCR4 and anti-FIV antibodies. cDNAs encoding the feline CXCR4
homolog were cloned from both T-lymphoblastoid and kidney cell lines.
Feline CXCR4 displayed 94.9% amino acid sequence identity with human CXCR4
and was found to be expressed widely on cell lines susceptible to infection
with cell culture-adapted strains FIV. Ectopic expression of feline CXCR4
on human cells rendered the cells susceptible to FIV-dependent fusion.
Moreover, feline CXCR4 was found to be as efficient as human CXCR4 in
supporting cell fusion between CD4- expressing murine fibroblast cells and
either HIV type 1 (HIV-1) or HIV- 2 Env-expressing human cells. Previous
studies have demonstrated that feline cells expressing human CD4 are not
susceptible to infection with HIV-1; therefore, further restrictions to
HIV-1 Env-dependent fusion may exist in feline cells. As feline and human
CXCR4 support both FIV- and HIV-dependent cell fusion, these results
suggest a close evolutionary link between FIV and HIV and a common
mechanism of infection involving an interaction between the virus and a
member of the seven-transmembrane domain chemokine receptor family of
molecules.
Copyright © 1997, American Society for Microbiology
Shared usage of the chemokine receptor CXCR4 by the feline and human immunodeficiency viruses
Department of Veterinary Pathology, University of Glasgow Veterinary School, United Kingdom. b.willett@vet.gla.ac.uk
This article has been cited by other articles:
| J. Bacteriol. | Mol. Cell. Biol. | Microbiol. Mol. Biol. Rev. |
|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|