Philip M Murphy

University of Cambridge, Cambridge, England, United Kingdom

Are you Philip M Murphy?

Claim your profile

Publications (190)1369.33 Total impact

  • [Show abstract] [Hide abstract] ABSTRACT: WHIM syndrome is an autosomal dominant immunodeficiency disease caused by mutations affecting the carboxy-terminus of CXCR4. To characterize novel genetic causes of the syndrome, we recruited a pediatric patient with possible WHIM syndrome, performed CXCR4 gene sequencing and compared his clinical phenotype and CXCR4 tail amino acid sequences with other patients with WHIM syndrome carrying CXCR4 R334X mutations. We identified and biochemically characterized a heterozygous 5 base pair deletion (nucleotides 986–990) located in the portion of the open reading frame (ORF) of CXCR4 that encodes the carboxy-terminal domain of the receptor. This CXCR4 L329fs mutation causes a frame-shift at codon 329 resulting in replacement of the final 24 predicted amino acids of the receptor with 12 missense amino acids. Like previously reported WHIM mutations, this frame-shift mutation CXCR4 L329fs decreased receptor downregulation in response to the CXCR4 agonist CXCL12 in patient PBMCs as well as in transfected K562 and HEK 293 cells, but increased calcium flux responses in K562 cells to CXCL12 stimulation. Thus, CXCR4 L329fs appears to be a de novo autosomal dominant frame-shift gain-of-function mutation that like other carboxy-terminus mutations causes WHIM syndrome. The same CXCR4 L329fs frame-shift variant has been reported to occur in tumor cells from a patient with Waldenström’s Macroglobulemia (WM), but is caused by a distinct genetic mechanism: insertion of a single nucleotide in the L329 codon, providing additional evidence that the carboxy-terminus of CXCR4 is a genetic hotspot for mutation.
    No preview · Article · Apr 2016 · Journal of Clinical Immunology
  • [Show abstract] [Hide abstract] ABSTRACT: Infectious agents are often considered potential triggers for chronic inflammatory disease, including autoimmunity; however, direct evidence is usually lacking. Here we show that following control of acute infection of mice with the myotropic Colombiana strain of Trypanosoma cruzi, parasites persisted in tissue at low levels associated with development of systemic necrotizing vasculitis. Lesions occurred in many but not all organs and tissues, with skeletal muscle arteries most severely affected, associated with myositis, atrophy, paresis/paralysis and death. Histopathology showed fibrinoid vascular necrosis, rare amastigote nests within skeletal muscle myocytes, and massive leukocyte infiltrates composed mainly of inflammatory monocytes, F4/80+ macrophages and T. cruzi tetramer-specific CD8+ T lymphocytes capable of producing IFNγ and TNFα, but not IL-17. T. cruzi-specific IgG was detected in serum from infected mice, but antibody deposits and neutrophilic inflammation were not features of the lesions. Thus, T. cruzi infection of mice may be a specific infectious trigger of paralyzing systemic necrotizing vasculitis most severely affecting skeletal muscle, driven by pathogen-specific Type I immune responses.
    No preview · Article · Feb 2016 · Infection and Immunity
  • Source
    David H. McDermott · Ji-Liang Gao · Philip M. Murphy
    [Show abstract] [Hide abstract] ABSTRACT: We recently reported a 59 year old female, designated WHIM-09, who was born with the rare immunodeficiency disease WHIM syndrome but underwent spontaneous phenotypic reversion as an adult. The causative WHIM mutation CXCR4 (R334X) was absent in her myeloid and erythroid lineage, but present in her lymphoid lineage and in epithelial cells, defining her as a somatic genetic mosaic. Genomic and hematologic analysis revealed chromothripsis (chromosome shattering) on one copy of chromosome 2, which deleted 164 genes including CXCR4 (R334X) in a single haematopoietic stem cell (HSC) (Fig. 1). Experiments in mice indicated that deleting one copy of Cxcr4 is sufficient to confer a selective advantage for engraftment of transplanted HSCs, suggesting a mechanism for clinical cure in WHIM-09. Genome editing may allow autologous transplantation of HSCs lacking one copy of CXCR4 without bone marrow conditioning as a general cure strategy in WHIM syndrome, safely recapitulating the outcome in patient WHIM-09. Figure 1.Chromothripsis (chromosomal shattering) resulted in clinical cure of a patient with a rare immunodeficiency (WHIM syndrome) by deleting the mutant copy of CXCR4.
    Full-text · Article · Aug 2015
  • Zhanzhuo Li · Xin Xu · Ido D Weiss · Orit Jacobson · Philip M Murphy
    [Show abstract] [Hide abstract] ABSTRACT: Hematopoietic chimerism established by allogeneic bone marrow transplantation is known to promote donor-specific organ allograft tolerance; however, clinical application is limited by the need for toxic host conditioning and "megadoses" of donor bone marrow cells. A potential solution to this problem has been suggested by the observation that recipient bone marrow mobilization by the CXCR4 antagonist AMD3100 promotes chimerism in congenic bone marrow transplantation experiments in mice. Here we report that a single subcutaneous dose of 10 mg/kg AMD3100 in recipient C57BL/6 mice was able to enhance hematopoietic chimerism when complete MHC-mismatched BALB/c donor bone marrow cells were transplanted one hour after drug dosing. However, levels of chimerism measured 30 days post-transplantation were not sustained when mice were reexamined on day 90 post transplantation. Moreover, transient chimerism induced by this protocol did not support robust donor-specific skin allograft tolerance. Using the same transient immunosuppression protocol, we confirmed that "megadoses" of donor bone marrow cells could induce durable chimerism associated with donor-specific skin allograft tolerance without AMD3100 pre-treatment. We conclude that in this protocol AMD3100 pretreatment may empty bone marrow niches that become reoccupied by allogeneic donor hematopoietic progenitor cells but not by true long-lived donor hematopoietic stem cells, resulting in short-lived chimerism and failure to support durable donor-specific allograft tolerance. Copyright © 2015. Published by Elsevier B.V.
    No preview · Article · Jul 2015 · Transplant Immunology
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: We examined gene expression levels of multiple chemokines and chemokine receptors during Pneumocystis murina infection in wild-type and immunosuppressed mice, using microarrays and qPCR. In wild-type mice, expression of chemokines that are ligands for Ccr2, Cxcr3, Cxcr6, and Cxcr2 increased at days 32 to 41 post-infection, with a return to baseline by day 75 to 150. Concomitant increases were seen in Ccr2,Cxcr3, and Cxcr6, but not in Cxcr2 expression. Induction of these same factors also occurred in CD40-ligand and CD40 knockout mice but only at a much later time-point, during uncontrolled Pneumocystis pneumonia (PCP). Expression of CD4 Th1 markers was increased in wild-type mice during clearance of infection. Ccr2 and Cx3cr1 knockout mice cleared Pneumocystis infection with kinetics similar to wild-type mice, and all animals developed anti-Pneumocystis antibodies. Upregulation of Ccr2, Cxcr3, and Cxcr6 and their ligands supports an important role for T helper cells and mononuclear phagocytes in the clearance of Pneumocystis infection. However, based on the current and prior studies, no single chemokine receptor appears to be critical to the clearance of Pneumocystis. Copyright © 2015. Published by Elsevier Masson SAS.
    Full-text · Article · Jun 2015 · Microbes and Infection
  • Source
    Philip M. Murphy
    Preview · Article · Jun 2015 · Frontiers in Immunology
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Cx3cr1, the receptor for the chemokine Cx3cl1 (fractalkine), has been implicated in the progression and severity of Alzheimer's disease-like pathology in mice, but the underlying mechanisms remain unclear. A complicating factor is that Cx3cr1 has been demonstrated in both neurons and microglia. Here, we have dissected the differences between neuronal and microglial Cx3cr1, specifically by comparing direct amyloid-β-induced toxicity in cultured, mature, microglia-depleted hippocampal neurons from wild-type and Cx3cr1-/- mice. Wild-type neurons expressed both Cx3cl1 and Cx3cr1 and released Cx3cl1 in response to amyloid-β. Knockout of neuronal Cx3cr1 abated amyloid-β-induced lactate dehydrogenase release. Furthermore, amyloid-β differentially induced depression of pre- and postsynaptic components of miniature excitatory postsynaptic currents, in a peptide conformation-dependent manner. Knockout of neuronal Cx3cr1 abated effects of both amyloid-β conformational states, which were differentiable by aggregation kinetics and peptide morphology. We obtained similar results after both acute and chronic treatment of cultured neurons with the Cx3cr1 antagonist F1. Thus, neuronal Cx3cr1 may impact Alzheimer's disease-like pathology by modulating conformational state-dependent amyloid-β-induced synaptotoxicity.
    Full-text · Article · Jun 2015 · PLoS ONE
  • No preview · Article · Jun 2015
  • [Show abstract] [Hide abstract] ABSTRACT: Chemokines, and their receptors, are essential regulators of in vivo leukocyte migration and, some years ago, a systematic nomenclature system was developed for the chemokine receptor family. Chemokine receptor biology and biochemistry was recently extensively reviewed (Bachelerie et al., 2014). In this review we also highlighted a new component to the nomenclature system that incorporates receptors previously known as 'scavenging', or 'decoy', chemokine receptors on the basis of their lack of classical signaling responses to ligand binding and their general ability to scavenge, or sequester, their cognate chemokine ligands. These molecules are now collectively referred to as 'atypical chemokine receptors', or ACKRs, and play fundamental roles in regulating in vivo responses to chemokines. This commentary highlights this new addition to the chemokine receptor nomenclature system and provides brief information on the four receptors currently covered by this nomenclature. This article is protected by copyright. All rights reserved.
    No preview · Article · May 2015 · British Journal of Pharmacology
  • [Show abstract] [Hide abstract] ABSTRACT: Atypical chemokine receptor 1 (Ackr1; previously known as the Duffy antigen receptor for chemokines or Darc) is thought to regulate acute inflammatory responses in part by scavenging inflammatory CC and CXC chemokines; however, evidence for a role in chronic inflammation has been lacking. Here we investigated the role of Ackr1 in chronic inflammation, in particular in the setting of atherogenesis, using the apolipoprotein E-deficient (ApoE(-/-)) mouse model. Ackr1(-/-)ApoE(-/-) and Ackr1(+/+)ApoE(-/-) littermates were obtained by crossing ApoE(-/-) mice and Ackr1(-/-) mice on a C57BL/6J background. Ackr1 (+/+)ApoE(-/-)mice fed a Western diet upregulated Ackr1 expression in the aorta and had markedly increased atherosclerotic lesion size compared with Ackr1(-/-)ApoE(-/-) mice. This difference was observed in both the whole aorta and the aortic root in both early and late stages of the model. Ackr1 deficiency did not affect serum cholesterol levels or macrophage, collagen or smooth muscle cell content in atherosclerotic plaques, but significantly reduced the expression of Ccl2 and Cxcl1 in the whole aorta of ApoE(-/-) mice. In addition, Ackr1 deficiency resulted in a modest decrease in inflammatory mononuclear phagocyte content in aorta and blood in the model. Ackr1 deficiency appears to be protective in the ApoE knockout model of atherogenesis, but is associated with only modest changes in cytokine and chemokine expression as well as T cell subset frequency and inflammatory macrophage content. Published by Oxford University Press on behalf of the European Society of Cardiology 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
    No preview · Article · Apr 2015 · Cardiovascular Research
  • [Show abstract] [Hide abstract] ABSTRACT: AMD3100 (plerixafor), is a specific CXCR4 antagonist approved by the FDA for mobilizing hematopoietic stem cells from bone marrow to blood for transplantation in cancer. AMD3100 also mobilizes most mature leukocyte subsets to blood; however, their source and trafficking potential have not been fully delineated. Here, we show that a single injection of AMD3100 10 mg/kg into C57Bl/6 mice rapidly mobilizes (peak ∼ 2.5 hours) the same leukocyte subsets to blood as in humans. Using this model, we found that AMD3100 mobilization of neutrophils, lymphocytes and monocytes to blood isn't reduced by splenectomy or by blockade of lymphocyte egress from lymph node with FTY720, but is coupled to i) reduced content of each of these cell types in the bone marrow; ii) reduced T-cell numbers in thymuses; iii) increased lymphocytes in lymph nodes; and iv) increased neutrophil and monocyte content in the lung. Direct intrathymic labeling showed that AMD3100 selectively mobilizes naïve thymic CD4(+) and CD8(+) T cells to blood. Finally, AMD3100-induced neutrophil mobilization to blood did not reduce neutrophil trafficking to thioglycollate-inflamed peritoneum. Thus, AMD3100 redistributes lymphocytes, monocytes and neutrophils from primary immune organs to secondary immune organs, peripheral tissues and blood, without compromising neutrophil trafficking to inflamed sites. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Mar 2015 · European Journal of Immunology
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Chromothripsis is a catastrophic cellular event recently described in cancer in which chromosomes undergo massive deletion and rearrangement. Here, we report a case in which chromothripsis spontaneously cured a patient with WHIM syndrome, an autosomal dominant combined immunodeficiency disease caused by gain-of-function mutation of the chemokine receptor CXCR4. In this patient, deletion of the disease allele, CXCR4(R334X), as well as 163 other genes from one copy of chromosome 2 occurred in a hematopoietic stem cell (HSC) that repopulated the myeloid but not the lymphoid lineage. In competitive mouse bone marrow (BM) transplantation experiments, Cxcr4 haploinsufficiency was sufficient to confer a strong long-term engraftment advantage of donor BM over BM from either wild-type or WHIM syndrome model mice, suggesting a potential mechanism for the patient's cure. Our findings suggest that partial inactivation of CXCR4 may have general utility as a strategy to promote HSC engraftment in transplantation. Copyright © 2015 Elsevier Inc. All rights reserved.
    Full-text · Article · Feb 2015 · Cell
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Atypical Chemokine Receptor 1 (ACKR1), previously known as Duffy Antigen Receptor for Chemokines, stands out among chemokine receptors for high selective expression on cerebellar Purkinje neurons. Although ACKR1 ligands activate Purkinje cells in vitro, evidence for ACKR1 regulation of brain function in vivo is lacking. Here we demonstrate that Ackr1 −/− mice have markedly impaired balance and ataxia on a rotating rod and increased tremor when injected with harmaline, which induces whole-body tremor by activating Purkinje cells. Ackr1 −/− mice also exhibited impaired exploratory behavior, increased anxiety-like behavior and frequent episodes of marked hypoactivity under low-stress conditions. Surprisingly, Ackr1 +/− had similar behavioral abnormalities, indicating pronounced haploinsufficiency. The behavioral phenotype of Ackr1 −/− mice was the opposite of mouse models of cerebellar degeneration, and the defects persisted when Ackr1 was deficient only on non-hematopoietic cells. Together, the results suggest that normal motor function and behavior may partly depend on negative regulation of Purkinje cell activity by Ackr1.
    Full-text · Article · Jul 2014 · Behavior Genetics
  • Source
    Full-text · Dataset · Apr 2014
  • [Show abstract] [Hide abstract] ABSTRACT: Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145-176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human Genome Nomenclature Committee.
    No preview · Article · Apr 2014 · Pharmacological reviews
  • No preview · Article · Feb 2014 · Nature Immunology
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: WHIM syndrome is a rare immunodeficiency disorder caused by gain-of-function mutations in the G protein-coupled chemokine receptor CXCR4. The CXCR4 antagonist plerixafor, which is FDA-approved for stem cell mobilization in cancer and administered for that indication at 0.24 mg/kg, has been shown in short-term (1-2 week) Phase 1 dose escalation studies to correct neutropenia and other cytopenias in WHIM syndrome; however, long-term safety and long-term hematologic and clinical efficacy data are lacking. Here we report results from the first long-term clinical trial of plerixafor in any disease, in which three adults with WHIM syndrome self-injected 0.01-0.02 mg/kg (4-8% of the FDA-approved dose) subcutaneously twice daily for 6 months. Circulating leukocytes were durably increased throughout the trial in all patients, and this was associated with fewer infections and improvement in warts in combination with imiquimod; however immunoglobulin levels and specific vaccine responses were not fully restored. No drug-associated side effects were observed. These results provide preliminary evidence for the safety and clinical efficacy of long-term, low-dose plerixafor in WHIM syndrome, and support its continued study as mechanism-based therapy in this disease. The ClinicalTrials.gov identifier for this study is NCT00967785.
    Full-text · Article · Feb 2014 · Blood
  • [Show abstract] [Hide abstract] ABSTRACT: Systemic Candida albicans infection causes high morbidity and mortality and is associated with neutropenia; however, the roles of other innate immune cells in pathogenesis are poorly defined. Here, using a mouse model of systemic candidiasis, we found that resident macrophages accumulated in the kidney, the main target organ of infection, and formed direct contacts with the fungus in vivo mainly within the first few hours after infection. Macrophage accumulation and contact with Candida were both markedly reduced in mice lacking chemokine receptor CX3CR1, which was found almost exclusively on resident macrophages in uninfected kidneys. Infected Cx3cr1-/- mice uniformly succumbed to Candida-induced renal failure, but exhibited clearance of the fungus in all other organs tested. Renal macrophage deficiency in infected Cx3cr1-/- mice was due to reduced macrophage survival, not impaired proliferation, trafficking, or differentiation. In humans, the dysfunctional CX3CR1 allele CX3CR1-M280 was associated with increased risk of systemic candidiasis. Together, these data indicate that CX3CR1-mediated renal resident macrophage survival is a critical innate mechanism of early fungal control that influences host survival in systemic candidiasis.
    No preview · Article · Nov 2013 · The Journal of clinical investigation
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Shifts in commensal microbiota composition are emerging as a hallmark of gastrointestinal inflammation. In particular, outgrowth of γ-proteobacteria has been linked to the etiology of inflammatory bowel disease and the pathologic consequences of infections. Here we show that following acute Toxoplasma gondii gastrointestinal infection of mice, control of commensal outgrowth is a highly coordinated process involving both the host response and microbial signals. Notably, neutrophil emigration to the intestinal lumen results in the generation of organized intraluminal structures that encapsulate commensals and limit their contact with the epithelium. Formation of these luminal casts depends on the high-affinity N-formyl peptide receptor, Fpr1. Consequently, after infection, mice deficient in Fpr1 display increased microbial translocation, poor commensal containment, and increased mortality. Altogether, our study describes a mechanism by which the host rapidly contains commensal pathobiont outgrowth during infection. Further, these results reveal Fpr1 as a major mediator of host commensal interaction during dysbiosis.
    Full-text · Article · Sep 2013 · Cell host & microbe
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Saint Louis polyomavirus (STLPyV) was recently discovered in human feces. Using random-primed rolling circle amplification combined with deep sequencing, we have found a divergent variant of STLPyV in a sanitized human skin wart specimen. The result strongly suggests that STLPyV directly infects humans and is not simply a dietary contaminant.
    Full-text · Article · Aug 2013 · Genome Announcements

Publication Stats

15k Citations
1,369.33 Total Impact Points

Institutions

  • 2015
    • University of Cambridge
      Cambridge, England, United Kingdom
  • 2012
    • National Institute of Allergy and Infectious Disease
      United States
  • 1988-2012
    • National Institute of Allergy and Infectious Diseases
      • • Laboratory of Immunoregulation
      • • Laboratory of Parasitic Diseases (LPD)
      베서스다, Maryland, United States
  • 2007
    • National Eye Institute
      베서스다, Maryland, United States
  • 2005
    • National Human Genome Research Institute
      베서스다, Maryland, United States
  • 2003
    • Boston University
      • Division of Mathematics
      Boston, Massachusetts, United States
  • 2002
    • NCI-Frederick
      Фредерик, Maryland, United States
    • Brigham and Women's Hospital
      Boston, Massachusetts, United States
  • 1998-2001
    • National Institutes of Health
      • Laboratory of Host Defenses
      Maryland, United States