The Second Extracellular Loop of CCR5 Is the Major Determinant of Ligand Specificity*

The chemokine receptor CCR5 binds macrophage inflammatory protein (MIP)-1α, MIP-1β, and regulated on activation, normal T-cell expressed and secreted (RANTES), and constitutes the major co-receptor allowing infection of CD4+ T lymphocytes, macrophages, and microglial cells by macrophage-tropic strains of human and simian immunodeficiency virus. CCR5 is most closely related to CCR2b, another chemokine receptor that responds to monocyte chemoattractant protein (MCP)-1, MCP-2, MCP-3, and MCP-4. We have investigated by mutagenesis the regions of CCR5 and CCR2b involved in the specificity of binding and functional response to their respective ligands. We demonstrate that the key region of CCR5 involved in its specific interaction with MIP-1α, MIP-1β, and RANTES, and its subsequent activation, lies within the second extracellular loop (and possibly the adjacent transmembrane segments). Conversely, the NH2-terminal domain of CCR2b is responsible for the high affinity binding of MCP-1, but is not sufficient to confer activation of the intracellular cascades. Extracellular loops of the receptor, among which the second loop plays a prominent role, are necessary to achieve efficient signaling of the receptor. These data complement our previous mapping of CCR5 domains functionally involved in the fusion process with the human immunodeficiency virus envelope, and will help in the development of agents able to interfere with the early steps of viral infection.

[1]  P. Gray,et al.  Molecular Cloning and Functional Characterization of a Novel Human CC Chemokine Receptor (CCR5) for RANTES, MIP-1β, and MIP-1α* , 1996, The Journal of Biological Chemistry.

[2]  M. Goldsmith,et al.  Multiple Extracellular Elements of CCR5 and HIV-1 Entry: Dissociation from Response to Chemokines , 1996, Science.

[3]  Marc Parmentier,et al.  Regions in β-Chemokine Receptors CCR5 and CCR2b That Determine HIV-1 Cofactor Specificity , 1996, Cell.

[4]  Jennifer C. Lee,et al.  CXC Chemokines Bind to Unique Sets of Selectivity Determinants That Can Function Independently and Are Broadly Distributed on Multiple Domains of Human Interleukin-8 Receptor B , 1996, The Journal of Biological Chemistry.

[5]  M. Baggiolini,et al.  HIV blocked by chemokine antagonist , 1996, Nature.

[6]  J. Sanes,et al.  The encephalomyocarditis virus internal ribosome entry site allows efficient coexpression of two genes from a recombinant provirus in cultured cells and in embryos , 1991, Molecular and cellular biology.

[7]  Stephen C. Peiper,et al.  Identification of a major co-receptor for primary isolates of HIV-1 , 1996, Nature.

[8]  Marc Parmentier,et al.  A Dual-Tropic Primary HIV-1 Isolate That Uses Fusin and the β-Chemokine Receptors CKR-5, CKR-3, and CKR-2b as Fusion Cofactors , 1996, Cell.

[9]  William C. Olson,et al.  CD4-dependent, antibody-sensitive interactions between HIV-1 and its co-receptor CCR-5 , 1996, Nature.

[10]  Marc Parmentier,et al.  Resistance to HIV-1 infection in Caucasian individuals bearing mutant alleles of the CCR-5 chemokine receptor gene , 1996, Nature.

[11]  Paul E. Kennedy,et al.  HIV-1 Entry Cofactor: Functional cDNA Cloning of a Seven-Transmembrane, G Protein-Coupled Receptor , 1996, Science.

[12]  Steven M. Wolinsky,et al.  Relative resistance to HIV–1 infection of CD4 lymphocytes from persons who remain uninfected despite multiple high–risk sexual exposures , 1996, Nature Medicine.

[13]  Richard A Koup,et al.  Homozygous Defect in HIV-1 Coreceptor Accounts for Resistance of Some Multiply-Exposed Individuals to HIV-1 Infection , 1996, Cell.

[14]  B. Dewald,et al.  Interleukin-8 and related chemotactic cytokines--CXC and CC chemokines. , 1994, Advances in immunology.

[15]  C. Combadière,et al.  Cloning and functional expression of CC CKR5, a human monocyte CC chemokine receptor selective for MIP‐1α, MIP‐1β, and RANTES , 1996, Journal of leukocyte biology.

[16]  P. Proost,et al.  Monocyte chemoattractant protein-3, but not monocyte chemoattractant protein-2, is a functional ligand of the human monocyte chemoattractant protein-1 receptor. , 1995, Journal of immunology.

[17]  R. Mark,et al.  Amino terminus of the interleukin-8 receptor is a major determinant of receptor subtype specificity. , 1992, The Journal of biological chemistry.

[18]  Robin A. Weiss,et al.  The T4 gene encodes the AIDS virus receptor and is expressed in the immune system and the brain , 1986, Cell.

[19]  I. Charo,et al.  The amino-terminal extracellular domain of the MCP-1 receptor, but not the RANTES/MIP-1alpha receptor, confers chemokine selectivity. Evidence for a two-step mechanism for MCP-1 receptor activation. , 1996, The Journal of biological chemistry.

[20]  T. Schwartz,et al.  Potent inhibition of HIV-1 infectivity in macrophages and lymphocytes by a novel CCR5 antagonist. , 1997, Science.

[21]  S. Coughlin,et al.  Molecular cloning and functional expression of two monocyte chemoattractant protein 1 receptors reveals alternative splicing of the carboxyl-terminal tails. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[22]  R. Horuk.  The interleukin-8-receptor family: from chemokines to malaria. , 1994, Immunology today.

[23]  M. Parmentier,et al.  Stable expression of the human TSH receptor in CHO cells and characterization of differentially expressing clones. , 1990, Biochemical and biophysical research communications.

[24]  R. Horuk,et al.  Partial functional mapping of the human interleukin-8 type A receptor. Identification of a major ligand binding domain. , 1993, The Journal of biological chemistry.

[25]  Ying Sun,et al.  The β-Chemokine Receptors CCR3 and CCR5 Facilitate Infection by Primary HIV-1 Isolates , 1996, Cell.

[26]  Virginia Litwin,et al.  HIV-1 entry into CD4+ cells is mediated by the chemokine receptor CC-CKR-5 , 1996, Nature.

[27]  Joseph Sodroski,et al.  CD4-induced interaction of primary HIV-1 gp120 glycoproteins with the chemokine receptor CCR-5 , 1996, Nature.

[28]  R. Horuk,et al.  The Promiscuous Chemokine Binding Profile of the Duffy Antigen/Receptor for Chemokines Is Primarily Localized to Sequences in the Amino-terminal Domain (*) , 1995, The Journal of Biological Chemistry.

[29]  B. Chesebro,et al.  Failure of human immunodeficiency virus entry and infection in CD4-positive human brain and skin cells , 1990, Journal of virology.

[30]  C. Broder,et al.  The block to HIV-1 envelope glycoprotein-mediated membrane fusion in animal cells expressing human CD4 can be overcome by a human cell component(s). , 1993, Virology.

[31]  S. Arya,et al.  Identification of RANTES, MIP-1α, and MIP-1β as the Major HIV-Suppressive Factors Produced by CD8+ T Cells , 1995, Science.

[32]  J. W. Parce,et al.  Biosensors based on the energy metabolism of living cells: the physical chemistry and cell biology of extracellular acidification. , 1992, Biosensors & bioelectronics.

[33]  G Vassart,et al.  Molecular cloning and functional expression of a new human CC-chemokine receptor gene. , 1996, Biochemistry.

[34]  C. Broder,et al.  Differential utilization of CCR5 by macrophage and T cell tropic simian immunodeficiency virus strains. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[35]  K. Matsushima,et al.  Properties of the novel proinflammatory supergene "intercrine" cytokine family. , 1991, Annual review of immunology.

[36]  J J Goedert,et al.  Genetic Restriction of HIV-1 Infection and Progression to AIDS by a Deletion Allele of the CKR5 Structural Gene , 1996, Science.

[37]  C. Broder,et al.  CC CKR5: A RANTES, MIP-1α, MIP-1ॆ Receptor as a Fusion Cofactor for Macrophage-Tropic HIV-1 , 1996, Science.