Previous Article | Next Article ![]()
Journal of Virology, September 2001, p. 8752-8760, Vol. 75, No. 18
Department of Microbiology and Myles H. Thaler Center for
AIDS and Human Retrovirus Research, University of Virginia,
Charlottesville, Virginia 22908,1 and
Millennium Pharmaceuticals, Cambridge, Massachusetts
021392
Received 1 September 2000/Accepted 18 June 2001
The presence or absence of the receptor CD4 and the coreceptors
CCR5 and CXCR4 restrict the cell tropism of human immunodeficiency virus type 1 (HIV-1). Despite the importance of thymic infection by
HIV-1, conflicting reports regarding the expression of HIV-1 coreceptors on human thymocytes have not been resolved. We assayed the
expression and function of the major HIV-1 coreceptors, CCR5 and CXCR4,
as well as CCR4 and CCR7 as controls, on human thymocytes. We detected
CCR5 on 2.5% of thymocytes, CXCR4 on 53% of the cells, and CCR4 on
16% and CCR7 on 11% of human thymocytes. Moreover, infection by R5
HIV-1 did not significantly induce expression of CCR5. We found that
two widely used anti-CCR5 monoclonal antibodies cross-reacted with
CCR8, which may account for discrepancies among published reports of
CCR5 expression on primary cells. This cross-reactivity could be
eliminated by deletion of amino acids 2 through 4 of CCR8. Chemotaxis
assays showed that SDF-1, which binds CXCR4; MDC, which
binds CCR4; and ELC, which binds CCR7, mediated significant chemotaxis of thymocytes. In contrast, MIP-1
0022-538X/01/$04.00+0 DOI: 10.1128/JVI.75.18.8752-8760.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Expression and Function of Chemokine Receptors on
Human Thymocytes: Implications for Infection by Human Immunodeficiency
Virus Type 1
, whose receptor is CCR5, did not induce significant chemotaxis. Our results indicate that CXCR4, CCR4, CCR7, and their chemokine ligands may be involved in
thymocyte migration during development in the thymus. CCR5 and its
ligands, however, are likely not involved in these processes. Furthermore, the pattern of CCR5 and CXCR4 expression that we found may
explain the greater susceptibility of human thymocytes to infection by
HIV-1 isolates capable of using CXCR4 in cell entry compared to those
that use only CCR5.
*
Corresponding author. Mailing address: Department of
Microbiology and Myles H. Thaler Center for AIDS and Human Retrovirus Research, University of Virginia, Charlottesville, VA 22908. Phone: (804) 982-1597. Fax: (804) 982-1590. E-mail:
dc9b{at}virginia.edu.
This article has been cited by other articles:
| J. Bacteriol. | Mol. Cell. Biol. | Microbiol. Mol. Biol. Rev. |
|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|