Pros and cons of a missing chemokine receptor—Comments on “Is the European spatial distribution of the HIV-1-resistant CCR5-Δ32 allele formed by a breakdown of the pathocenosis due to the historical Roman expansion?” by Eric Faure and Manuela Royer-Carenzi (2008)

Introduction: Blocking Human Immunodeficiency Virus type 1 (HIV-1) entry via C-C chemokine receptor 5 (CCR5) inhibition has remained an essential strategy in HIV drug discovery. This underlies the development of CCR5 blockers, such as Maraviroc, which, however, elicits undesirable side effects despite its potency. Background: Recent lead optimization efforts led to the discovery of novel 1-heteroaryl-1,3-propanediamine derivatives; Compd-21 and -34, which were ~3 times more potent than Maraviroc, with improved pharmacokinetics. However, atomistic molecular interaction mechanism of how slight structural variance between these inhibitors significantly affects their binding profiles have not been elucidated. Method: This study employed explicit lipid bilayer molecular dynamics (MD) simulations, and advance analyses to explore these inhibitory discrepancies. Results: Findings revealed that the thiophene moiety substitution common to Compd-21 and -34 enhanced their CCR5- inhibitory activities due to complementary high-affinity interactions with Trp862.60, Tyr1083.32, Tyr2516.51, Glu2837.39. These cumulatively accounted for their ΔGbind which were higher than Maraviroc. Binding dynamics further revealed that the compounds mediated direct competitive inhibition at CCR5 by blocking the gp120 V3 loop. Furthermore, constituent tropane and triazole moieties in the compounds commonly engaged in interactions with Glu2837.39 and Trp862.60, respectively. Structural analyses also revealed that both Compd-21 and -34 elicited distinct internal dynamic effect on CCR5 relative to Maraviroc. Conclusion: Structural modifications at the thiophene substituent and the addition of new functional groups to the triazole ring may enhance inhibitor competition with gp120 V3-loop. Findings herein highlighted would contribute to future structure-based design of inhibitors of HIV-1 CCR5 with improved potencies.

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Combined Genotypes of CCR5, CCR2, SDF1, and HLA Genes Can Predict the Long-Term Nonprogressor Status in Human Immunodeficiency Virus-1–Infected Individuals

Blood ◽

10.1182/blood.v93.3.936 ◽

1999 ◽

Vol 93 (3) ◽

pp. 936-941 ◽

Cited By ~ 151

Author(s):

Magdalena Magierowska ◽

Ioannis Theodorou ◽

Patrice Debré ◽

Françoise Sanson ◽

Brigitte Autran ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Chemokine Receptor ◽

Multivariate Logistic Regression Model ◽

Hla B27 ◽

Hla Alleles ◽

Immunodeficiency Virus ◽

Combined Genotypes ◽

Hiv 1

Abstract Human immunodeficiency virus (HIV)-1–infected long-term nonprogressors (LT-NP) represent less than 5% of HIV-1–infected patients. In this work, we tried to understand whether combined genotypes of CCR5-▵32, CCR2-64I, SDF1-3′A and HLA alleles can predict the LT-NP status. Among the chemokine receptor genotypes, only the frequency of the CCR5-▵32 allele was significantly higher in LT-NP compared with the group of standard progressors. The predominant HLA alleles in LT-NP were HLA-A3, HLA-B14, HLA-B17, HLA-B27, HLA-DR6, and HLA-DR7. A combination of both HLA and chemokine receptor genotypes integrated in a multivariate logistic regression model showed that if a subject is heterozygous for CCR5-▵32 and homozygous for SDF1 wild type, his odds of being LT-NP are increased by 16-fold, by 47-fold when a HLA-B27 allele is present with HLA-DR6 absent, and by 47-fold also if at least three of the following alleles are present: HLA-A3, HLA-B14, HLA-B17, HLA-DR7. This model allowed a correct classification of 70% of LT-NPs and 81% of progressors, suggesting that the host’s genetic background plays an important role in the evolution of HIV-1. The chemokine receptor and chemokine genes along with the HLA genotype can serve as predictors of HIV-1 outcome for classification of HIV-1–infected subjects as LT-NPs or progressors.

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HIV-1 gp120 and chemokine activation of Pyk2 and mitogen-activated protein kinases in primary macrophages mediated by calcium-dependent, pertussis toxin–insensitive chemokine receptor signaling

Blood ◽

10.1182/blood.v98.10.2909 ◽

2001 ◽

Vol 98 (10) ◽

pp. 2909-2916 ◽

Cited By ~ 97

Author(s):

Manuela Del Corno ◽

Qing-Hua Liu ◽

Dominique Schols ◽

Erik de Clercq ◽

Sandra Gessani ◽

...

Keyword(s):

Protein Kinase ◽

Pertussis Toxin ◽

Chemokine Receptor ◽

Calcium Release ◽

Mitogen Activated Protein Kinase ◽

Macrophage Infection ◽

Amino Terminal ◽

Crac Channels ◽

Mitogen Activated Protein ◽

Hiv 1

Abstract Human immunodeficiency virus type 1 (HIV-1) uses the chemokine receptors CCR5 and CXCR4 as coreceptors for entry. It was recently demonstrated that HIV-1 glycoprotein 120 (gp120) elevated calcium and activated several ionic signaling responses in primary human macrophages, which are important targets for HIV-1 in vivo. This study shows that chemokine receptor engagement by both CCR5-dependent (R5) and CXCR4-dependent (X4) gp120 led to rapid phosphorylation of the focal adhesion-related tyrosine kinase Pyk2 in macrophages. Pyk2 phosphorylation was also induced by macrophage inflammatory protein-1β (MIP-1β) and stromal cell–derived factor-1α, chemokine ligands for CCR5 and CXCR4. Activation was blocked by EGTA and by a potent blocker of calcium release–activated Ca++(CRAC) channels, but was insensitive to pertussis toxin (PTX), implicating CRAC-mediated extracellular Ca++ influx but not Gαi protein-dependent mechanisms. Coreceptor engagement by gp120 and chemokines also activated 2 members of the mitogen-activated protein kinase (MAPK) superfamily, c-Jun amino-terminal kinase/stress-activated protein kinase and p38 MAPK. Furthermore, gp120-stimulated macrophages secreted the chemokines monocyte chemotactic protein-1 and MIP-1β in a manner that was dependent on MAPK activation. Thus, the gp120 signaling cascade in macrophages includes coreceptor binding, PTX-insensitive signal transduction, ionic signaling including Ca++ influx, and activation of Pyk2 and MAPK pathways, and leads to secretion of inflammatory mediators. HIV-1 Env signaling through these pathways may contribute to dysregulation of uninfected macrophage functions, new target cell recruitment, or modulation of macrophage infection.

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IL-8 responsiveness defines a subset of CD8 T cells poised to kill

Blood ◽

10.1182/blood-2004-03-1067 ◽

2004 ◽

Vol 104 (12) ◽

pp. 3463-3471 ◽

Cited By ~ 56

Author(s):

Christoph Hess ◽

Terry K. Means ◽

Patrick Autissier ◽

Tonia Woodberry ◽

Marcus Altfeld ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Chemokine Receptor ◽

Cd8 T Cells ◽

Molecular Mechanisms ◽

Cell Subset ◽

Cd8 T Cell ◽

Effector Memory ◽

Immune System Activation ◽

Hiv 1

CD8 T cells play a key role in host defense against intracellular pathogens. Efficient migration of these cells into sites of infection is therefore intimately linked to their effector function. The molecular mechanisms that control CD8 T-cell trafficking into sites of infection and inflammation are not well understood, but the chemokine/chemokine receptor system is thought to orchestrate this process. Here we systematically examined the chemokine receptor profile expressed on human CD8 T cells. Surprisingly, we found that CXC chemokine receptor 1 (CXCR1), the predominant neutrophil chemokine receptor, defined a novel interleukin-8/CXC ligand 8 (IL-8/CXCL8)–responsive CD8 T-cell subset that was enriched in perforin, granzyme B, and interferon-γ (IFNγ), and had high cytotoxic potential. CXCR1 expression was down-regulated by antigen stimulation both in vitro and in vivo, suggesting antigen-dependent shaping of the migratory characteristics of CD8 T cells. On virus-specific CD8 T cells from persons with a history of Epstein-Barr virus (EBV) and influenza infection, CXCR1 expression was restricted to terminally differentiated effector memory cells. In HIV-1 infection, CXCR1-expressing HIV-1–specific CD8 T cells were present only in persons who were able to control HIV-1 replication during structured treatment interruptions. Thus, CXCR1 identifies a subset of CD8 T cells poised for immediate cytotoxicity and early recruitment into sites of innate immune system activation.

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Mechanistic Evaluation of the Pros and Cons of Digital RT-LAMP for HIV-1 Viral Load Quantification on a Microfluidic Device and Improved Efficiency via a Two-Step Digital Protocol

Analytical Chemistry ◽

10.1021/ac3037206 ◽

2013 ◽

Vol 85 (3) ◽

pp. 1540-1546 ◽

Cited By ~ 58

Author(s):

Bing Sun ◽

Feng Shen ◽

Stephanie E. McCalla ◽

Jason E. Kreutz ◽

Mikhail A. Karymov ◽

...

Keyword(s):

Viral Load ◽

Microfluidic Device ◽

Pros And Cons ◽

Viral Load Quantification ◽

Hiv 1

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Small molecule inhibitor of HIV-1 cell fusion blocks chemokine receptor-mediated function

Journal of Leukocyte Biology ◽

10.1002/jlb.64.1.6 ◽

1998 ◽

Vol 64 (1) ◽

pp. 6-13 ◽

Cited By ~ 33

Author(s):

O. M. Z. Howard ◽

Thomas Korte ◽

Nadya I. Tarasova ◽

Michael Grimm ◽

Jim A. Turpin ◽

...

Keyword(s):

Cell Fusion ◽

Small Molecule ◽

Chemokine Receptor ◽

Small Molecule Inhibitor ◽

Molecule Inhibitor ◽

Hiv 1

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A V3 Loop-Dependent gp120 Element Disrupted by CD4 Binding Stabilizes the Human Immunodeficiency Virus Envelope Glycoprotein Trimer

Journal of Virology ◽

10.1128/jvi.02587-09 ◽

2010 ◽

Vol 84 (7) ◽

pp. 3147-3161 ◽

Cited By ~ 53

Author(s):

Shi-Hua Xiang ◽

Andrés Finzi ◽

Beatriz Pacheco ◽

Kevin Alexander ◽

Wen Yuan ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Receptor Binding ◽

Chemokine Receptor ◽

Chemokine Receptors ◽

Envelope Glycoproteins ◽

V3 Loop ◽

Virus Envelope ◽

Hydrophobic Patch ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Human immunodeficiency virus (HIV-1) entry into cells is mediated by a trimeric complex consisting of noncovalently associated gp120 (exterior) and gp41 (transmembrane) envelope glycoproteins. The binding of gp120 to receptors on the target cell alters the gp120-gp41 relationship and activates the membrane-fusing capacity of gp41. Interaction of gp120 with the primary receptor, CD4, results in the exposure of the gp120 third variable (V3) loop, which contributes to binding the CCR5 or CXCR4 chemokine receptors. We show here that insertions in the V3 stem or polar substitutions in a conserved hydrophobic patch near the V3 tip result in decreased gp120-gp41 association (in the unliganded state) and decreased chemokine receptor binding (in the CD4-bound state). Subunit association and syncytium-forming ability of the envelope glycoproteins from primary HIV-1 isolates were disrupted more by V3 changes than those of laboratory-adapted HIV-1 envelope glycoproteins. Changes in the gp120 β2, β19, β20, and β21 strands, which evidence suggests are proximal to the V3 loop in unliganded gp120, also resulted in decreased gp120-gp41 association. Thus, a gp120 element composed of the V3 loop and adjacent beta strands contributes to quaternary interactions that stabilize the unliganded trimer. CD4 binding dismantles this element, altering the gp120-gp41 relationship and rendering the hydrophobic patch in the V3 tip available for chemokine receptor binding.

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