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Sample records for cd8 chemokine receptors

  1. CD8 chemokine receptors in chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Smyth, L J C; Starkey, C; Gordon, F S

    2008-01-01

    Increased lung CD8 cells and their expression of chemokine receptors CXCR3 and CCR5 have been previously reported in chronic obstructive pulmonary disease (COPD). Alterations of CD8-CCR3 and -CCR4 expression and their ligands in COPD patients have not been fully investigated. The objective...... of this study was to assess in COPD patients: (i) broncho-alveolar lavage (BAL) CD8 CCR3 and CCR4 expression in COPD patients; and (ii) airway levels of the CCR3 ligands, CCL11 and CCL5. Multi-parameter flow cytometric analysis was used to assess BAL CD3 and CD8-chemokine receptor expression in COPD patients......, smokers and healthy non-smokers (HNS). CCL5 and CCL11 levels were measured in BAL, and from the supernatants of lung resection explant cultures. CD8-CCR3 and -CCR5 expression (means) were increased in COPD patients (22% and 46% respectively) and smokers (20% and 45%) compared with HNS (3% and 22%); P

  2. Functional analysis of the CC chemokine receptor 5 (CCR5) on virus-specific CD8+ T cells following coronavirus infection of the central nervous system

    International Nuclear Information System (INIS)

    Glass, William G.; Lane, Thomas E.

    2003-01-01

    Intracranial infection of C57BL/6 mice with mouse hepatitis virus (MHV) results in an acute encephalomyelitis followed by a demyelinating disease similar in pathology to the human disease multiple sclerosis (MS). T cells participate in both defense and disease progression following MHV infection. Expression of chemokine receptors on activated T cells is important in allowing these cells to traffic into and accumulate within the central nervous system (CNS) of MHV-infected mice. The present study evaluated the contributions of CCR5 to the activation and trafficking of virus-specific CD8 + T cells into the MHV-infected CNS mice. Comparable numbers of virus-specific CD8 + T cells derived from immunized CCR5 +/+ or CCR5 -/- mice were present within the CNS of MHV-infected RAG1 -/- mice following adoptive transfer, indicating that CCR5 is not required for trafficking of these cells into the CNS. RAG1 -/- recipients of CCR5 -/- -derived CD8 + T cells exhibited a modest, yet significant (P ≤ 0.05), reduction in viral burden within the brain which correlated with increased CTL activity and IFN-γ expression. Histological analysis of RAG1 -/- recipients of either CCR5 +/+ or CCR5 -/- -derived CD8 + T cells revealed only focal areas of demyelination with no significant differences in white matter destruction. These data indicate that CCR5 signaling on CD8 + T cells modulates antiviral activities but is not essential for entry into the CNS

  3. Immune Alterations in CD8+T Cells Are Associated with Neuronal C-C and C-X-C Chemokine Receptor Regulation Through Adenosine A2A Receptor Signaling in a BTBR T+Itpr3tf/J Autistic Mouse Model.

    Science.gov (United States)

    Ahmad, Sheikh F; Ansari, Mushtaq A; Nadeem, Ahmed; Bakheet, Saleh A; Mohammad, Raish; Attia, Sabry M

    2018-03-01

    Associative studies on a range of neurodevelopmental disorders have identified relationships between behavioral deficits and immune system function. The BTBR T + Itpr3 tf /J (BTBR) mouse strain displays aberrant characteristics in its social behavior and immune responses, providing a significant opportunity to examine the relationship between behavior and the immune system. This study investigated the influence of adenosine A2A receptor activity on C-C and C-X-C chemokine receptors involved in autism in the BTBR mouse model. A2A receptors have previously been targeted in clinical trials by potential therapeutics with neuroprotective, immunomodulatory, and analgesic properties. In this study, we examined the effects of A2A receptor antagonist SCH5826 (SCH) and A2A receptor agonist CGS21680 (CGS) on C-C and C-X-C chemokine receptors (CCR3, CCR4, CCR5, CCR6, CCR7, CXCR3, CXCR4, and CXCR5) on splenic CD8 + T cells in the BTBR autistic mouse model. We also assessed the C-C and C-X-C chemokine receptors mRNA levels in brain tissue. Our results showed that CCR3 + , CCR4 + , CCR5 + , CCR6 + , CCR7 + , CXCR3 + , CXCR4 + , and CXCR5 + production in splenic CD8 + T cells decreased significantly in BTBR-CGS-treated mice in comparison with that in BTBR control and BTBR-SCH-treated mice. In addition, RT-PCR analysis revealed decreased gene expression levels for C-C and C-X-C chemokine receptors in the brain tissue of BTBR-CGS-treated mice, whereas these levels were significantly increased in BTBR control and BTBR-SCH-treated mice. Our results suggest that treating BTBR mice with CGS decreases C-C and C-X-C chemokine receptor signaling and might therefore provide a unique avenue for developing future therapies for autism and neuroimmunological disorders.

  4. CD8(+) T Cells Produce the Chemokine CXCL10 in Response to CD27/CD70 Costimulation To Promote Generation of the CD8(+) Effector T Cell Pool

    NARCIS (Netherlands)

    Peperzak, Victor; Veraar, Elise A. M.; Xiao, Yanling; Babala, Nikolina; Thiadens, Klaske; Brugmans, Marieke; Borst, Jannie

    2013-01-01

    Various cell types can produce the chemokine CXCL10 in response to IFN-gamma stimulation. CXCL10 is generally viewed as a proinflammatory chemokine that promotes recruitment of CD8(+) and Th1-type CD4(+) effector T cells to infected or inflamed nonlymphoid tissues. We show that CXCL10 plays a role

  5. Effector CD8^+ T cells migrate via chemokine-enhanced generalized L'evy walks

    Science.gov (United States)

    Banigan, Edward; Harris, Tajie; Christian, David; Liu, Andrea; Hunter, Christopher

    2012-02-01

    Chemokines play a central role in regulating processes essential to the immune function of T cells, such as their migration within lymphoid tissues and targeting of pathogens in sites of inflammation. In order to understand the role of the chemokine CXCL10 during chronic infection by the parasite T. gondii, we analyze tracks of migrating CD8^+ T cells in brain tissue. Surprisingly, we find that T cell motility is not described by a Brownian walk, but instead is consistent with a generalized L'evy walk consisting of L'evy-distributed runs alternating with pauses of L'evy-distributed durations. According to our model, this enables T cells to find rare targets more than an order of magnitude more efficiently than Brownian random walkers. The chemokine CXCL10 increases the migration speed without changing the character of the walk statistics. Thus, CD8^+ T cells use an efficient search strategy to facilitate an effective immune response, and CXCL10 aids them in shortening the average time to find rare targets.

  6. Keratinocyte cytokine and chemokine receptors.

    Science.gov (United States)

    Tüzün, Yalçin; Antonov, Meltem; Dolar, Neslihan; Wolf, Ronni

    2007-10-01

    Chemokines are a superfamily of small, secreted proteins that regulate cell traffic in homeostatic and inflammatory conditions. Keratinocytes synthesize many chemokines, including members of the CC and CXC subfamilies, such as regulated on activation of normal T-cell expressed and secreted, gamma-interferon inducible protein-10, monokine induced by gamma-interferon, and thymus- and activation-regulated chemokine. They also express some chemokine receptors that mediate the inflammatory or immune response by attracting various kinds of leukocytes.

  7. Probing Biased Signaling in Chemokine Receptors

    DEFF Research Database (Denmark)

    Amarandi, Roxana Maria; Hjortø, Gertrud Malene; Rosenkilde, Mette Marie

    2016-01-01

    The chemokine system mediates leukocyte migration during homeostatic and inflammatory processes. Traditionally, it is described as redundant and promiscuous, with a single chemokine ligand binding to different receptors and a single receptor having several ligands. Signaling of chemokine receptor...

  8. Teleost Chemokines and Their Receptors

    Directory of Open Access Journals (Sweden)

    Steve Bird

    2015-11-01

    Full Text Available Chemokines are a superfamily of cytokines that appeared about 650 million years ago, at the emergence of vertebrates, and are responsible for regulating cell migration under both inflammatory and physiological conditions. The first teleost chemokine gene was reported in rainbow trout in 1998. Since then, numerous chemokine genes have been identified in diverse fish species evidencing the great differences that exist among fish and mammalian chemokines, and within the different fish species, as a consequence of extensive intrachromosomal gene duplications and different infectious experiences. Subsequently, it has only been possible to establish clear homologies with mammalian chemokines in the case of some chemokines with well-conserved homeostatic roles, whereas the functionality of other chemokine genes will have to be independently addressed in each species. Despite this, functional studies have only been undertaken for a few of these chemokine genes. In this review, we describe the current state of knowledge of chemokine biology in teleost fish. We have mainly focused on those species for which more research efforts have been made in this subject, specially zebrafish (Danio rerio, rainbow trout (Oncorhynchus mykiss and catfish (Ictalurus punctatus, outlining which genes have been identified thus far, highlighting the most important aspects of their expression regulation and addressing any known aspects of their biological role in immunity. Finally, we summarise what is known about the chemokine receptors in teleosts and provide some analysis using recently available data to help characterise them more clearly.

  9. Polymorphic expression in the CD8alpha chain surface receptor of African lions (Panthera leo).

    Science.gov (United States)

    Bull, Marta E; Gebhard, Douglas G; Tompkins, Wayne A F; Kennedy-Stoskopf, Suzanne

    2002-01-15

    Free-ranging African lion (Panthera leo) peripheral blood mononuclear cells (PBMC) were examined using flow cytometry and antibodies developed for use in the domestic cat to determine if phenotypic changes occurred in lion lymphocytes as a result of feline immunodeficiency virus (FIV) infection. The percentage of CD8 cells from lion peripheral blood was considerably lower than in the domestic cat. Lions with elevated levels of CD8+ cells were typically infected with FIV, similar to observations in the domestic cat. Antibodies against the alpha chain of the CD8 receptor (monoclonal antibody (mAb) 3.357) did not react consistently in all lions examined. Flow cytometric analysis determined that approximately 82 and 80% of the animals from Kruger and Hluhluwe-Umfolozi National Parks in South Africa reacted with the monoclonal antibody against the alpha chain of CD8 receptor, while only 17% of the lions in Etosha National Park in Namibia cross-reacted with the CD8alpha chain. There was no apparent correlation between FIV status and CD8alpha chain reactivity. The relative isolation of Etosha from the other two parks could explain the marked difference in CD8alpha chain expression and suggests that lions similar to other mammalian species demonstrate polymorphic expression of the CD8alpha chain (197).

  10. Effect of ranitidine on soluble interleukin 2 receptors and CD8 molecules in surgical patients

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Mynster, T; Jensen, S

    1994-01-01

    The effect of perioperative immunomodulation with the H2-receptor antagonist ranitidine on postoperative changes in soluble interleukin (IL) 2 receptor and soluble CD8 levels was assessed in 24 patients undergoing major elective abdominal surgery. Eleven patients were randomized to receive...... transfusion were similar in the two groups. Serum concentrations of soluble IL-2 receptor and CD8 were measured before operation (day 0) and in the morning of postoperative days 1, 3 and 9 using commercial enzyme-linked immunosorbent assay kits. In patients treated with ranitidine, the serum level of soluble...... developed postoperative infectious complications. No significant differences were shown in soluble CD8 concentration during the postoperative period. The postoperative change in soluble IL-2 receptor level may reflect lymphocyte activation status; ranitidine appears to promote activation of mainly CD4...

  11. Chemokine receptor expression by inflammatory T cells in EAE

    DEFF Research Database (Denmark)

    Mony, Jyothi Thyagabhavan; Khorooshi, Reza; Owens, Trevor

    2014-01-01

    Chemokines direct cellular infiltration to tissues, and their receptors and signaling pathways represent targets for therapy in diseases such as multiple sclerosis (MS). The chemokine CCL20 is expressed in choroid plexus, a site of entry of T cells to the central nervous system (CNS). The CCL20...... immunofluorescence. Consistent with flow cytometry data some but not all CD4(+) T cells expressed CCR6 within infiltrates. CD4-negative CCR6(+) cells included macrophage/microglial cells. Thus we have for the first time directly studied CD4(+) and CD8(+) T cells in the CNS of mice with peak EAE, and determined IFNγ...

  12. The Significance of Tumor Necrosis Factor Receptor Type II in CD8+Regulatory T Cells and CD8+Effector T Cells.

    Science.gov (United States)

    Ye, Lin-Lin; Wei, Xiao-Shan; Zhang, Min; Niu, Yi-Ran; Zhou, Qiong

    2018-01-01

    Tumor necrosis factor (TNF) is a pleiotropic cytokine that has both pro-inflammatory and anti-inflammatory functions. The biological functions of TNF are mediated by two receptors, TNF receptor type I (TNFR1) and TNF receptor type II (TNFR2). TNFR1 is expressed universally on almost all cell types and has been extensively studied, whereas TNFR2 is mainly restricted to immune cells and some tumor cells and its role is far from clarified. Studies have shown that TNFR2 mediates the stimulatory activity of TNF on CD4 + Foxp3 + regulatory T cells (Tregs) and CD8 + Foxp3 + Tregs, and is involved in the phenotypic stability, proliferation, activation, and suppressive activity of Tregs. TNFR2 can also be expressed on CD8 + effector T cells (Teffs), which delivers an activation signal and cytotoxic ability to CD8 + Teffs during the early immune response, as well as an apoptosis signal to terminate the immune response. TNFR2-induced abolition of TNF receptor-associated factor 2 (TRAF2) degradation may play an important role in these processes. Consequently, due to the distribution of TNFR2 and its pleiotropic effects, TNFR2 appears to be critical to keeping the balance between Tregs and Teffs, and may be an efficient therapeutic target for tumor and autoimmune diseases. In this review, we summarize the biological functions of TNFR2 expressed on CD8 + Foxp3 + Tregs and CD8 + Teffs, and highlight how TNF uses TNFR2 to coordinate the complex events that ultimately lead to efficient CD8 + T cell-mediated immune responses.

  13. Effect of ranitidine on soluble interleukin 2 receptors and CD8 molecules in surgical patients

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Mynster, T; Jensen, S

    1994-01-01

    intravenous ranitidine 100 mg twice daily for 4 days from skin incision, followed by oral ranitidine 150 mg twice daily for a further 5 days; 13 control patients received no ranitidine. Routine blood analysis, clinical data, duration of surgery, anaesthesia, antibiotic prophylaxis and perioperative blood......The effect of perioperative immunomodulation with the H2-receptor antagonist ranitidine on postoperative changes in soluble interleukin (IL) 2 receptor and soluble CD8 levels was assessed in 24 patients undergoing major elective abdominal surgery. Eleven patients were randomized to receive...... transfusion were similar in the two groups. Serum concentrations of soluble IL-2 receptor and CD8 were measured before operation (day 0) and in the morning of postoperative days 1, 3 and 9 using commercial enzyme-linked immunosorbent assay kits. In patients treated with ranitidine, the serum level of soluble...

  14. Effect of ranitidine on soluble interleukin 2 receptors and CD8 molecules in surgical patients

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Mynster, T; Jensen, S

    1994-01-01

    The effect of perioperative immunomodulation with the H2-receptor antagonist ranitidine on postoperative changes in soluble interleukin (IL) 2 receptor and soluble CD8 levels was assessed in 24 patients undergoing major elective abdominal surgery. Eleven patients were randomized to receive...... intravenous ranitidine 100 mg twice daily for 4 days from skin incision, followed by oral ranitidine 150 mg twice daily for a further 5 days; 13 control patients received no ranitidine. Routine blood analysis, clinical data, duration of surgery, anaesthesia, antibiotic prophylaxis and perioperative blood...... transfusion were similar in the two groups. Serum concentrations of soluble IL-2 receptor and CD8 were measured before operation (day 0) and in the morning of postoperative days 1, 3 and 9 using commercial enzyme-linked immunosorbent assay kits. In patients treated with ranitidine, the serum level of soluble...

  15. Chapter 8. Activation mechanisms of chemokine receptors

    DEFF Research Database (Denmark)

    Jensen, Pia C; Rosenkilde, Mette M

    2009-01-01

    Chemokine receptors belong to the large family of 7-transmembrane (7TM) G-protein-coupled receptors. These receptors are targeted and activated by a variety of different ligands, indicating that activation is a result of similar molecular mechanisms but not necessarily similar modes of ligand...... binding. Attempts to unravel the activation mechanism of 7TM receptors have led to the conclusion that activation involves movements of the transmembrane segments VI and VII in particular, as recently gathered in the Global Toggle Switch Model. However, to understand the activation mechanism completely......, more research has to be done in this field. Chemokine receptors are interesting tools in this matter. First, the chemokine system has a high degree of promiscuity that allows several chemokines to target one receptor in different ways, as well as a single chemokine ligand to target several receptors...

  16. The role of CC chemokine receptor 5 in antiviral immunity

    DEFF Research Database (Denmark)

    Nansen, Anneline; Christensen, Jan Pravsgaard; Andreasen, Susanne Ørding

    2002-01-01

    response to lymphocytic choriomeningitis virus in mice lacking CCR5 (CCR5(-/-) mice). This infection is a classical model for studying antiviral immunity, and influx of CCR5-expressing CD8(+) T cells and macrophages is essential for both virus control and associated immunopathology. Results showed......The CC chemokine receptor CCR5 is an important coreceptor for human immunodeficiency virus (HIV), and there is a major thrust to develop anti-CCR5-based therapies for HIV-1. However, it is not known whether CCR5 is critical for a normal antiviral T-cell response. This study investigated the immune...... influence of CCR5 was found, not even when viral peptide was used as local trigger instead of live virus. Finally, long-term CD8(+) T cell-mediated immune surveillance was efficiently sustained in CCR5(-/-) mice. Taken together, these results indicate that expression of CCR5 is not critical for T cell...

  17. Atypical chemokine receptors in cancer: friends or foes?

    Science.gov (United States)

    Massara, Matteo; Bonavita, Ornella; Mantovani, Alberto; Locati, Massimo; Bonecchi, Raffaella

    2016-06-01

    The chemokine system is a fundamental component of cancer-related inflammation involved in all stages of cancer development. It controls not only leukocyte infiltration in primary tumors but also angiogenesis, cancer cell proliferation, and migration to metastatic sites. Atypical chemokine receptors are a new, emerging class of regulators of the chemokine system. They control chemokine bioavailability by scavenging, transporting, or storing chemokines. They can also regulate the activity of canonical chemokine receptors with which they share the ligands by forming heterodimers or by modulating their expression levels or signaling activity. Here, we summarize recent results about the role of these receptors (atypical chemokine receptor 1/Duffy antigen receptor for chemokine, atypical chemokine receptor 2/D6, atypical chemokine receptor 3/CXC-chemokine receptor 7, and atypical chemokine receptor 4/CC-chemokine receptor-like 1) on the tumorigenesis process, indicating that their effects are strictly dependent on the cell type on which they are expressed and on their coexpression with other chemokine receptors. Indeed, atypical chemokine receptors inhibit tumor growth and progression through their activity as negative regulators of chemokine bioavailability, whereas, on the contrary, they can promote tumorigenesis when they regulate the signaling of other chemokine receptors, such as CXC-chemokine receptor 4. Thus, atypical chemokine receptors are key components of the regulatory network of inflammation and immunity in cancer and may have a major effect on anti-inflammatory and immunotherapeutic strategies. © Society for Leukocyte Biology.

  18. Chemokines

    Directory of Open Access Journals (Sweden)

    Richard Horuk

    2007-01-01

    Full Text Available Chemokines are a family of polypeptides that direct the migration of leukocytestoward a site of infection. They play a major role in autoimmune disease and chemokine receptors have recently been found to mediate HIV-1 fusion. In this short review we examine the role of chemokines in host defence and in the pathophysiology of autoimmune diseases. We conclude by discussing various therapeutic approaches that target chemokine receptors and that could be beneficial in disease.

  19. Interaction of chemokines with their receptors--from initial chemokine binding to receptor activating steps

    DEFF Research Database (Denmark)

    Thiele, Stefanie; Rosenkilde, Mette Marie

    2014-01-01

    and surveillance. Chemokines are a group of 8-12 kDa large peptides with a secondary structure consisting of a flexible N-terminus and a core-domain usually stabilized by two conserved disulfide bridges. They mainly interact with the extracellular domains of their cognate 7TM receptors. Affinityand activity......-contributing interactions are attributed to different domains and known to occur in two steps. Here, knowledge on chemokine and receptor domains involved in the first binding-step and the second activation-step is reviewed. A mechanism comprising at least two steps seems consistent; however, several intermediate...... interactions possibly occur, resulting in a multi-step process, as recently proposed for other 7TM receptors. Overall, the N-terminus of chemokine receptors is pivotal for binding of all chemokines. During receptor activation, differences between the two major chemokine subgroups occur, as CC-chemokines mainly...

  20. NOD1 cooperates with TLR2 to enhance T cell receptor-mediated activation in CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Blandine C Mercier

    Full Text Available Pattern recognition receptors (PRR, like Toll-like receptors (TLR and NOD-like receptors (NLR, are involved in the detection of microbial infections and tissue damage by cells of the innate immune system. Recently, we and others have demonstrated that TLR2 can additionally function as a costimulatory receptor on CD8 T cells. Here, we establish that the intracytosolic receptor NOD1 is expressed and functional in CD8 T cells. We show that C12-iEDAP, a synthetic ligand for NOD1, has a direct impact on both murine and human CD8 T cells, increasing proliferation and effector functions of cells activated via their T cell receptor (TCR. This effect is dependent on the adaptor molecule RIP2 and is associated with an increased activation of the NF-κB, JNK and p38 signaling pathways. Furthermore, we demonstrate that NOD1 stimulation can cooperate with TLR2 engagement on CD8 T cells to enhance TCR-mediated activation. Altogether our results indicate that NOD1 might function as an alternative costimulatory receptor in CD8 T cells. Our study provides new insights into the function of NLR in T cells and extends to NOD1 the recent concept that PRR stimulation can directly control T cell functions.

  1. Tumor Necrosis Factor (TNF) Receptor Superfamily Member 1b on CD8+ T Cells and TNF Receptor Superfamily Member 1a on Non-CD8+ T Cells Contribute Significantly to Upper Genital Tract Pathology Following Chlamydial Infection.

    Science.gov (United States)

    Manam, Srikanth; Thomas, Joshua D; Li, Weidang; Maladore, Allison; Schripsema, Justin H; Ramsey, Kyle H; Murthy, Ashlesh K

    2015-06-15

    We demonstrated previously that tumor necrosis factor α (TNF-α)-producing Chlamydia-specific CD8(+) T cells cause oviduct pathological sequelae. In the current study, we used wild-type C57BL/6J (WT) mice with a deficiency in genes encoding TNF receptor superfamily member 1a (TNFR1; TNFR1 knockout [KO] mice), TNF receptor superfamily member 1b (TNFR2; TNFR2 KO mice), and both TNFR1 and TNFR2 (TNFR1/2 double KO [DKO] mice) and mix-match adoptive transfers of CD8(+) T cells to study chlamydial pathogenesis. TNFR1 KO, TNFR2 KO, and TNFR1/2 DKO mice displayed comparable clearance of primary or secondary genital Chlamydia muridarum infection but significantly reduced oviduct pathology, compared with WT animals. The Chlamydia-specific total cellular cytokine response in splenic and draining lymph nodes and the antibody response in serum were comparable between the WT and KO animals. However, CD8(+) T cells from TNFR2 KO mice displayed significantly reduced activation (CD11a expression and cytokine production), compared with TNFR1 KO or WT animals. Repletion of TNFR2 KO mice with WT CD8(+) T cells but not with TNFR2 KO CD8(+) T cells and repletion of TNFR1 KO mice with either WT or TNFR1 KO CD8(+) T cells restored oviduct pathology to WT levels in both KO groups. Collectively, these results demonstrate that TNFR2-bearing CD8(+) T cells and TNFR1-bearing non-CD8(+) T cells contribute significantly to oviduct pathology following genital chlamydial infection. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Tumor Necrosis Factor Receptor 2 Restricts the Pathogenicity of CD8(+) T Cells in Mice With Colitis.

    Science.gov (United States)

    Punit, Shivesh; Dubé, Philip E; Liu, Cambrian Y; Girish, Nandini; Washington, M Kay; Polk, D Brent

    2015-10-01

    Tumor necrosis factor receptor 2 (TNFR2, Tnfrsf1b) regulates multiple aspects of immune function, but little is known about its role in the immunopathogenesis of inflammatory bowel disease (IBD). We investigated whether TNFR2 restricts the activity of specific immune cell subtypes to protect against the development of colitis in mice. Tnfr2(-/-) mice were crossed with interleukin (Il) 10(-/-) mice, which spontaneously develop colitis, to generate Il10(-/-)Tnfr2(-/-) mice. Colonic tissues were collected from Il10(-/-)Tnfr2(-/-) mice along with Il10(-/-) mice (controls) and analyzed by flow cytometry and histology. Bone marrow was transplanted into Il10(-/-) and Il10(-/-)Tnfr2(-/-) mice from Il10(-/-) or Il10(-/-)Tnfr2(-/-) donors by intravenous injection. CD8(+) T cells were neutralized in Il10(-/-)Tnfr2(-/-) mice by intraperitoneal injection of anti-CD8 or isotype control antibodies. Colitis was induced in Rag2(-/-) mice by intravenous injections of naïve CD8(+) T cells isolated from C57BL/6 or Tnfr2(-/-) mice. Il10(-/-)Tnfr2(-/-) mice spontaneously developed more severe colitis compared with Il10(-/-) controls, characterized by selective expansion of colonic CD8(+) T cells. Transplantation of TNFR2-deficient bone marrow resulted in significantly increased incidence and severity of colitis. Transcriptome analyses showed that the expression of genes regulated by TNFR2 were specific to CD8(+) T cells and included genes associated with risk for IBD. Depletion of CD8(+) T cells from Il10(-/-)Tnfr2(-/-) mice prevented colonic inflammation. Adoptive transfer of TNFR2-null naïve CD8(+) T cells compared with CD8(+) T cells from control mice increased the severity of colitis that developed in Rag2(-/-) mice. TNFR2 protects mice from colitis by inhibiting the expansion of colonic CD8(+) T cells. TNFR2 regulates expression of genes that regulate CD8(+) T cells and have been associated with susceptibility to IBD. Disruption in TNFR2 signaling might therefore be associated

  3. CD8 Lineage Commitment in the Absence of CD8

    OpenAIRE

    Goldrath, Ananda W.; Hogquist, Kristin A.; Bevan, Michael J.

    1997-01-01

    The absence of cytotoxic T lymphocyte activity and the failure of MHC class I–restricted T cell receptor (TCR) transgenic thymocytes to mature in CD8α-deficient mice suggest that CD8 may be essential for CD8 lineage commitment. We report that variants of the antigenic peptide that delete TCR transgenic thymocytes from CD8 wild-type but not CD8α-deficient mice can restore positive selection of CD8 lineage cells in the absence of CD8. The positively selected cells down-regulate CD4, up-regulate...

  4. Molecular piracy of chemokine receptors by herpesviruses.

    Science.gov (United States)

    Murphy, P M

    1994-01-01

    To succeed as a biological entity, viruses must exploit normal cellular functions and elude the host immune system; they often do so by molecular mimicry. One way that mimicry may occur is when viruses copy and modify host genes. The best studied examples of this are the oncogenes of RNA retroviruses, but a growing number of examples are also known for DNA viruses. So far they all come from just two groups of DNA viruses, the herpesviruses and poxviruses, and the majority of examples are for genes whose products regulate immune responses, such as cytokines, cytokine receptors, and complement control proteins. This review will focus on human and herpesvirus receptors for chemokines, a family of leukocyte chemoattractant and activating factors that are thought to be important mediators of inflammation. Although the biological roles of the viral chemokine receptor homologues are currently unknown, their connection to specific sets of chemokines has suggested a number of possible functions.

  5. Targeting cellular adhesion molecules, chemokines and chemokine receptors in rheumatoid arthritis

    NARCIS (Netherlands)

    Haringman, Jasper J.; Oostendorp, Roos L.; Tak, Paul P.

    2005-01-01

    The development of specific targeted therapies, such as anti-TNF-alpha treatment, for chronic inflammatory disorders such as rheumatoid arthritis, has significantly improved treatment, although not all patients respond. Targeting cellular adhesion molecules and chemokines/chemokine receptors as

  6. Increased generation of HIV-1 gp120-reactive CD8+ T cells by a DNA vaccine construct encoding the chemokine CCL3.

    Directory of Open Access Journals (Sweden)

    Inger Øynebråten

    Full Text Available DNA vaccines based on subunits from pathogens have several advantages over other vaccine strategies. DNA vaccines can easily be modified, they show good safety profiles, are stable and inexpensive to produce, and the immune response can be focused to the antigen of interest. However, the immunogenicity of DNA vaccines which is generally quite low needs to be improved. Electroporation and co-delivery of genetically encoded immune adjuvants are two strategies aiming at increasing the efficacy of DNA vaccines. Here, we have examined whether targeting to antigen-presenting cells (APC could increase the immune response to surface envelope glycoprotein (Env gp120 from Human Immunodeficiency Virus type 1 (HIV-1. To target APC, we utilized a homodimeric vaccine format denoted vaccibody, which enables covalent fusion of gp120 to molecules that can target APC. Two molecules were tested for their efficiency as targeting units: the antibody-derived single chain Fragment variable (scFv specific for the major histocompatibility complex (MHC class II I-E molecules, and the CC chemokine ligand 3 (CCL3. The vaccines were delivered as DNA into muscle of mice with or without electroporation. Targeting of gp120 to MHC class II molecules induced antibodies that neutralized HIV-1 and that persisted for more than a year after one single immunization with electroporation. Targeting by CCL3 significantly increased the number of HIV-1 gp120-reactive CD8+ T cells compared to non-targeted vaccines and gp120 delivered alone in the absence of electroporation. The data suggest that chemokines are promising molecular adjuvants because small amounts can attract immune cells and promote immune responses without advanced equipment such as electroporation.

  7. Selective suppression of chemokine receptor CXCR3 expression by interferon-beta1a in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F

    2002-01-01

    We studied the expression of chemokine receptors CCR1, CCR2, CCR3, CCR5, and CXCR3 on CD4 and CD8 positive T cells, and on CD14 positive monocytes in blood from 10 patients with relapsing-remitting multiple sclerosis (MS) at initiation of interferon (IFN)-beta treatment, after 1 month and after 3...

  8. CD8+ T Cell Response to Gammaherpesvirus Infection Mediates Inflammation and Fibrosis in Interferon Gamma Receptor-Deficient Mice.

    Directory of Open Access Journals (Sweden)

    Brigid M O'Flaherty

    Full Text Available Idiopathic pulmonary fibrosis (IPF, one of the most severe interstitial lung diseases, is a progressive fibrotic disorder of unknown etiology. However, there is growing appreciation for the role of viral infection in disease induction and/or progression. A small animal model of multi-organ fibrosis, which involves murine gammaherpesvirus (MHV68 infection of interferon gamma receptor deficient (IFNγR-/- mice, has been utilized to model the association of gammaherpesvirus infections and lung fibrosis. Notably, several MHV68 mutants which fail to induce fibrosis have been identified. Our current study aimed to better define the role of the unique MHV68 gene, M1, in development of pulmonary fibrosis. We have previously shown that the M1 gene encodes a secreted protein which possesses superantigen-like function to drive the expansion and activation of Vβ4+ CD8+ T cells. Here we show that M1-dependent fibrosis is correlated with heightened levels of inflammation in the lung. We observe an M1-dependent cellular infiltrate of innate immune cells with most striking differences at 28 days-post infection. Furthermore, in the absence of M1 protein expression we observed reduced CD8+ T cells and MHV68 epitope specific CD8+ T cells to the lungs-despite equivalent levels of viral replication between M1 null and wild type MHV68. Notably, backcrossing the IFNγR-/- onto the Balb/c background, which has previously been shown to exhibit weak MHV68-driven Vβ4+ CD8+ T cell expansion, eliminated MHV68-induced fibrosis-further implicating the activated Vβ4+ CD8+ T cell population in the induction of fibrosis. We further addressed the role that CD8+ T cells play in the induction of fibrosis by depleting CD8+ T cells, which protected the mice from fibrotic disease. Taken together these findings are consistent with the hypothesized role of Vβ4+ CD8+ T cells as mediators of fibrotic disease in IFNγR-/- mice.

  9. Co-receptor choice by V alpha14i NKT cells is driven by Th-POK expression rather than avoidance of CD8-mediated negative selection.

    Science.gov (United States)

    Engel, Isaac; Hammond, Kirsten; Sullivan, Barbara A; He, Xi; Taniuchi, Ichiro; Kappes, Dietmar; Kronenberg, Mitchell

    2010-05-10

    Mouse natural killer T (NKT) cells with an invariant V alpha14-J alpha18 rearrangement (V alpha14 invariant [V alpha14i] NKT cells) are either CD4(+)CD8(-) or CD4(-)CD8(-). Because transgenic mice with forced CD8 expression in all T cells exhibited a profound NKT cell deficit, the absence of CD8 has been attributed to negative selection. We now present evidence that CD8 does not serve as a coreceptor for CD1d recognition and that the defect in development in CD8 transgene homozygous mice is the result of a reduction in secondary T cell receptor alpha rearrangements. Thymocytes from mice hemizygous for the CD8 transgene have a less severe rearrangement defect and have functional CD8(+) V alpha14i NKT cells. Furthermore, we demonstrate that the transcription factor Th, Poxviruses and Zinc finger, and Krüppel family (Th-POK) is expressed by V alpha14i NKT cells throughout their differentiation and is necessary both to silence CD8 expression and for the functional maturity of V alpha14i NKT cells. We therefore suggest that Th-POK expression is required for the normal development of V alpha14i NKT cells and that the absence of CD8 expression by these cells is a by-product of such expression, as opposed to the result of negative selection of CD8-expressing V alpha14i NKT cells.

  10. Chemokines and Chemokine Receptors: Accomplices for Human Immunodeficiency Virus Infection and Latency

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    Zhuo Wang

    2017-10-01

    Full Text Available Chemokines are small chemotactic cytokines that are involved in the regulation of immune cell migration. Multiple functional properties of chemokines, such as pro-inflammation, immune regulation, and promotion of cell growth, angiogenesis, and apoptosis, have been identified in many pathological and physiological contexts. Human immunodeficiency virus (HIV infection is characterized by persistent inflammation and immune activation during both acute and chronic phases, and the “cytokine storm” is one of the hallmarks of HIV infection. Along with immune activation after HIV infection, an extensive range of chemokines and other cytokines are elevated, thereby generating the so-called “cytokine storm.” In this review, the effects of the upregulated chemokines and chemokine receptors on the processes of HIV infection are discussed. The objective of this review was to focus on the main chemokines and chemokine receptors that have been found to be associated with HIV infection and latency. Elevated chemokines and chemokine receptors have been shown to play important roles in the HIV life cycle, disease progression, and HIV reservoir establishment. Thus, targeting these chemokines and receptors and the other proteins of related signaling pathways might provide novel therapeutic strategies, and the evidence indicates a promising future regarding the development of a functional cure for HIV.

  11. T-cell receptor Vβ repertoire of CD8+ T-lymphocyte subpopulations in cutaneous leishmaniasis patients from the state of Rio de Janeiro, Brazil

    Science.gov (United States)

    Ferraz, Raquel; Cunha, Clarissa Ferreira; Pimentel, Maria Inês; Lyra, Marcelo Rosandiski; Schubach, Armando Oliveira; de Mendonça, Sérgio Coutinho Furtado; Da-Cruz, Alda Maria; Bertho, Alvaro Luiz

    2015-01-01

    In human cutaneous leishmaniasis (CL), the immune response is mainly mediated by T-cells. The role of CD8+ T-lymphocytes, which are related to healing or deleterious functions, in affecting clinical outcome is controversial. The aim of this study was to evaluate T-cell receptor diversity in late-differentiated effector (LDE) and memory CD8+ T-cell subsets in order to create a profile of specific clones engaged in deleterious or protective CL immune responses. Healthy subjects, patients with active disease (PAD) and clinically cured patients were enrolled in the study. Total CD8+ T-lymphocytes showed a disturbance in the expression of the Vβ2, Vβ9, Vβ13.2, Vβ18 and Vβ23 families. The analyses of CD8+T-lymphocyte subsets showed high frequencies of LDE CD8+T-lymphocytes expressing Vβ12 and Vβ22 in PAD, as well as effector-memory CD8+ T-cells expressing Vβ22. We also observed low frequencies of effector and central-memory CD8+ T-cells expressing Vβ2 in PAD, which correlated with a greater lesion size. Particular Vβ expansions point to CD8+ T-cell clones that are selected during CL immune responses, suggesting that CD8+ T-lymphocytes expressing Vβ12 or Vβ22 are involved in a LDE response and that Vβ2 contractions in memory CD8+T-cells are associated with larger lesions. PMID:26107186

  12. T-cell receptor Vβ repertoire of CD8+ T-lymphocyte subpopulations in cutaneous leishmaniasis patients from the state of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Raquel Ferraz

    2015-08-01

    Full Text Available In human cutaneous leishmaniasis (CL, the immune response is mainly mediated by T-cells. The role of CD8+ T-lymphocytes, which are related to healing or deleterious functions, in affecting clinical outcome is controversial. The aim of this study was to evaluate T-cell receptor diversity in late-differentiated effector (LDE and memory CD8+ T-cell subsets in order to create a profile of specific clones engaged in deleterious or protective CL immune responses. Healthy subjects, patients with active disease (PAD and clinically cured patients were enrolled in the study. Total CD8+ T-lymphocytes showed a disturbance in the expression of the Vβ2, Vβ9, Vβ13.2, Vβ18 and Vβ23 families. The analyses of CD8+T-lymphocyte subsets showed high frequencies of LDE CD8+T-lymphocytes expressing Vβ12 and Vβ22 in PAD, as well as effector-memory CD8+ T-cells expressing Vβ22. We also observed low frequencies of effector and central-memory CD8+ T-cells expressing Vβ2 in PAD, which correlated with a greater lesion size. Particular Vβ expansions point to CD8+ T-cell clones that are selected during CL immune responses, suggesting that CD8+ T-lymphocytes expressing Vβ12 or Vβ22 are involved in a LDE response and that Vβ2 contractions in memory CD8+T-cells are associated with larger lesions.

  13. Vitamin D receptor signals regulate effector and memory CD8 T cell responses to infections in mice.

    Science.gov (United States)

    Yuzefpolskiy, Yevgeniy; Baumann, Florian M; Penny, Laura A; Studzinski, George P; Kalia, Vandana; Sarkar, Surojit

    2014-12-01

    Vitamin D insufficiency is associated with broad-ranging human disease sequelae such as bone disease, cancer, cardiovascular disease, allergy, autoimmune disorders, diabetes, and infectious diseases. Disease risk and severity of a large proportion of the nonskeletal disorders heavily involve the cytotoxic cluster of differentiation (CD) 8 T lymphocyte (CTL) arm of cellular adaptive immunity. Considering the importance of vitamin D in CTL-dependent diseases, there is a critical need for systematic in-depth explorations into the role of vitamin D deficiency in generation and maintenance of CTL immunity during infections and vaccinations. With the use of wild-type (WT) vitamin D-sufficient mice and the vitamin D receptor knockout (Vdr(-/-)) mouse model of in vivo deficiency of vitamin D signaling, we systematically analyzed the impact of vitamin D deficiency on antigen-specific effector and memory CD8 T cell responses to acute viral and bacterial infections. WT and Vdr(-/-) mice were infected with lymphocytic choriomeningitis virus, a natural mouse pathogen, and antigen-specific CTL responses were analyzed during priming, expansion, contraction, and memory phases. Magnitude, breadth, cytokine production, and localization of antiviral effector and memory CTLs to lymphoid and nonlymphoid tissues were specifically assessed. The absence of vitamin D signals led to 1) aberrant CD8 T cell effector differentiation (∼2-fold lower granzyme B and reduced B cell lymphoma 2; P ≤ 0.05) and enhanced contraction (∼15% increase; P ≤ 0.05) in antigen-specific CTLs; 2) a significantly restricted (P ≤ 0.05) breadth of the antigen-specific CD8 T cell effector and memory repertoire; and 3) preferential localization of effector (∼2.5-fold increase; P ≤ 0.01) and memory (∼5-fold increase; P ≤ 0.001) CD8 T cells to the lymph nodes compared to nonlymphoid tissues. Our data show a previously unrecognized impact of vitamin D deficiency on the quantity, quality, breadth, and

  14. Chemokines and chemokine receptors in inflammation of the nervous system

    DEFF Research Database (Denmark)

    Huang, D; Han, Yong-Chang; Rani, M R

    2000-01-01

    This article focuses on the production of chemokines by resident glial cells of the nervous system. We describe studies in two distinct categories of inflammation within the nervous system: immune-mediated inflammation as seen in experimental autoimmune encephalomyelitis (EAE) or multiple sclerosis...... (MS) and post-traumatic inflammation. We provide evidence that chemokines play a role in amplifying the inflammatory reaction in EAE (and, probably, MS). In the context of neural trauma, chemokines appear to be primary stimuli for leukocyte recruitment. Strikingly, expression of monocyte...... that produce aggregates of simultaneous stimuli. These characteristics, in turn, mirror the expression patterns of the endogenous genes: MCP-1 is expressed under a variety of circumstances, while IP-10 appears primarily during immune-mediated processes that feature exposure of resident neuroglia to high levels...

  15. Cigarette Smoke Disturbs the Survival of CD8+ Tc/Tregs Partially through Muscarinic Receptors-Dependent Mechanisms in Chronic Obstructive Pulmonary Disease.

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    Gang Chen

    Full Text Available CD8+ T cells (Cytotoxic T cells, Tc are known to play a critical role in the pathogenesis of smoking related airway inflammation including chronic obstructive pulmonary disease (COPD. However, how cigarette smoke directly impacts systematic CD8+ T cell and regulatory T cell (Treg subsets, especially by modulating muscarinic acetylcholine receptors (MRs, has yet to be well elucidated.Circulating CD8+ Tc/Tregs in healthy nonsmokers (n = 15, healthy smokers (n = 15 and COPD patients (n = 18 were evaluated by flow cytometry after incubating with anti-CD3, anti-CD8, anti-CD25, anti-Foxp3 antibodies. Peripheral blood T cells (PBT cells from healthy nonsmokers were cultured in the presence of cigarette smoke extract (CSE alone or combined with MRs agonist/antagonist for 5 days. Proliferation and apoptosis were evaluated by flow cytometry using Ki-67/Annexin-V antibodies to measure the effects of CSE on the survival of CD8+ Tc/Tregs.While COPD patients have elevated circulating percentage of CD8+ T cells, healthy smokers have higher frequency of CD8+ Tregs. Elevated percentages of CD8+ T cells correlated inversely with declined FEV1 in COPD. CSE promoted the proliferation and inhibited the apoptosis of CD8+ T cells, while facilitated both the proliferation and apoptosis of CD8+ Tregs. Notably, the effects of CSE on CD8+ Tc/Tregs can be mostly simulated or attenuated by muscarine and atropine, the MR agonist and antagonist, respectively. However, neither muscarine nor atropine influenced the apoptosis of CD8+ Tregs.The results imply that cigarette smoking likely facilitates a proinflammatory state in smokers, which is partially mediated by MR dysfunction. The MR antagonist may be a beneficial drug candidate for cigarette smoke-induced chronic airway inflammation.

  16. Chemokines and chemokine receptors in susceptibility to HIV-1 infection and progression to AIDS.

    Science.gov (United States)

    Chatterjee, Animesh; Rathore, Anurag; Vidyant, Sanjukta; Kakkar, Kavita; Dhole, Tapan N

    2012-01-01

    A multitude of host genetic factors plays a crucial role in susceptibility to HIV-1 infection and progression to AIDS, which is highly variable among individuals and populations. This review focuses on the chemokine-receptor and chemokine genes, which were extensively studied because of their role as HIV co-receptor or co-receptor competitor and influences the susceptibility to HIV-1 infection and progression to AIDS in HIV-1 infected individuals.

  17. Genomic organization, annotation, and ligand-receptor inferences of chicken chemokines and chemokine receptor genes based on comparative genomics

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    Sze Sing-Hoi

    2005-03-01

    Full Text Available Abstract Background Chemokines and their receptors play important roles in host defense, organogenesis, hematopoiesis, and neuronal communication. Forty-two chemokines and 19 cognate receptors have been found in the human genome. Prior to this report, only 11 chicken chemokines and 7 receptors had been reported. The objectives of this study were to systematically identify chicken chemokines and their cognate receptor genes in the chicken genome and to annotate these genes and ligand-receptor binding by a comparative genomics approach. Results Twenty-three chemokine and 14 chemokine receptor genes were identified in the chicken genome. All of the chicken chemokines contained a conserved CC, CXC, CX3C, or XC motif, whereas all the chemokine receptors had seven conserved transmembrane helices, four extracellular domains with a conserved cysteine, and a conserved DRYLAIV sequence in the second intracellular domain. The number of coding exons in these genes and the syntenies are highly conserved between human, mouse, and chicken although the amino acid sequence homologies are generally low between mammalian and chicken chemokines. Chicken genes were named with the systematic nomenclature used in humans and mice based on phylogeny, synteny, and sequence homology. Conclusion The independent nomenclature of chicken chemokines and chemokine receptors suggests that the chicken may have ligand-receptor pairings similar to mammals. All identified chicken chemokines and their cognate receptors were identified in the chicken genome except CCR9, whose ligand was not identified in this study. The organization of these genes suggests that there were a substantial number of these genes present before divergence between aves and mammals and more gene duplications of CC, CXC, CCR, and CXCR subfamilies in mammals than in aves after the divergence.

  18. Chemokine receptor CCR5 in interferon-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Kristiansen, T B; Wittenhagen, P

    2007-01-01

    To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta).......To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta)....

  19. Efficient T-cell surveillance of the CNS requires expression of the CXC chemokine receptor 3

    DEFF Research Database (Denmark)

    Christensen, Jeanette Erbo; Nansen, Anneline; Moos, Torben

    2004-01-01

    T-cells play an important role in controlling viral infections inside the CNS. To study the role of the chemokine receptor CXCR3 in the migration and positioning of virus-specific effector T-cells within the brain, CXCR3-deficient mice were infected intracerebrally with lymphocytic choriomeningitis......-cell-mediated immunopathology. Quantitative analysis of the cellular infiltrate in CSF of infected mice revealed modest, if any, decrease in the number of mononuclear cells recruited to the meninges in the absence of CXCR3. However, immunohistological analysis disclosed a striking impairment of CD8+ T-cells from CXCR3......-deficient mice to migrate from the meninges into the outer layers of the brain parenchyma despite similar localization of virus-infected target cells. Reconstitution of CXCR3-deficient mice with wild-type CD8+ T-cells completely restored susceptibility to LCMV-induced meningitis. Thus, taken together, our...

  20. The role of chemokines and chemokine receptors in eosinophil activation during inflammatory allergic reactions

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    Oliveira S.H.P.

    2003-01-01

    Full Text Available Chemokines are important chemotactic cytokines that play a fundamental role in the trafficking of leukocytes to sites of inflammation. They are also potent cell-activating factors, inducing cytokine and histamine release and free radical production, a fact that makes them particularly important in the pathogenesis of allergic inflammation. The action of chemokines is regulated at the level of agonist production and processing as well as at the level of receptor expression and coupling. Therefore, an analysis of the ligands must necessarily consider receptors. Eosinophils are target cells involved in the allergic inflammatory response since they are able to release a wide variety of mediators including CC and CXC chemokines and express their receptors. These mediators could damage the airway epithelial cells and might be important to stimulate other cells inducing an amplification of the allergic response. This review focuses on recently emerging data pertaining to the importance of chemokines and chemokine receptors in promoting eosinophil activation and migration during the allergic inflammatory process. The analysis of the function of eosinophils and their chemokine receptors during allergic inflammation might be a good approach to understanding the determinants of asthma severity and to developing novel therapies.

  1. Chemokines and chemokine receptors in inflammation of the nervous system

    DEFF Research Database (Denmark)

    Huang, D; Han, Yong-Chang; Rani, M R

    2000-01-01

    chemoattractant protein (MCP)-1 and interferon-gamma-inducible protein-10 (IP-10) are largely restricted to astrocytes or other glial cells in these diverse pathological states. The remainder of the review focuses on studies that address the molecular mechanisms which underlie transcriptional regulation of three...... astrocyte-derived chemokines: MCP-1, IP-10 and beta-R1/interferon-gamma-inducible T-cell chemoattractant (I-TAC). Based on these studies, we propose that the complex promoters of these genes are marvelously organized for flexible and efficient response to challenge. In the case of MCP-1, several different...... stimuli can elicit gene transcription, acting through a conserved mechanism that includes binding of inducible transcription factors and recruitment of the constitutive factor Sp1. For IP-10 and beta-R1/I-TAC, it appears that efficient gene transcription occurs only in highly inflammatory circumstances...

  2. Combining regulatory T cell depletion and inhibitory receptor blockade improves reactivation of exhausted virus-specific CD8+ T cells and efficiently reduces chronic retroviral loads.

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    Kirsten K Dietze

    Full Text Available Chronic infections with human viruses, such as HIV and HCV, or mouse viruses, such as LCMV or Friend Virus (FV, result in functional exhaustion of CD8(+ T cells. Two main mechanisms have been described that mediate this exhaustion: expression of inhibitory receptors on CD8(+ T cells and expansion of regulatory T cells (Tregs that suppress CD8(+ T cell activity. Several studies show that blockage of one of these pathways results in reactivation of CD8(+ T cells and partial reduction in chronic viral loads. Using blocking antibodies against PD-1 ligand and Tim-3 and transgenic mice in which Tregs can be selectively ablated, we compared these two treatment strategies and combined them for the first time in a model of chronic retrovirus infection. Blocking inhibitory receptors was more efficient than transient depletion of Tregs in reactivating exhausted CD8(+ T cells and reducing viral set points. However, a combination therapy was superior to any single treatment and further augmented CD8(+ T cell responses and resulted in a sustained reduction in chronic viral loads. These results demonstrate that Tregs and inhibitory receptors are non-overlapping factors in the maintenance of chronic viral infections and that immunotherapies targeting both pathways may be a promising strategy to treat chronic infectious diseases.

  3. GM-CSF/IL-3/IL-5 receptor common β chain (CD131 expression as a biomarker of antigen-stimulated CD8+ T cells

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    Maric Dragan

    2008-04-01

    Full Text Available Abstract Background Upon Ag-activation cytotoxic T cells (CTLs produce IFN-γ GM-CSF and TNF-α, which deliver simultaneously pro-apoptotic and pro-inflammatory signals to the surrounding microenvironment. Whether this secretion affects in an autocrine loop the CTLs themselves is unknown. Methods Here, we compared the transcriptional profile of Ag-activated, Flu-specific CTL stimulated with the FLU M1:58-66 peptide to that of convivial CTLs expanded in vitro in the same culture. PBMCs from 6 HLA-A*0201 expressing donors were expanded for 7 days in culture following Flu M1:58-66 stimulation in the presence of 300 IU/ml of interleukin-2 and than sorted by high speed sorting to high purity CD8+ expressing T cells gated according to FluM1:58-66 tetrameric human leukocyte antigen complexes expression. Results Ag-activated CTLs displayed higher levels of IFN-γ, GM-CSF (CSF2 and GM-CSF/IL-3/IL-5 receptor common β- chain (CD131 but lacked completely expression of IFN-γ receptor-II and IFN-stimulated genes (ISGs. This observation suggested that Ag-activated CTLs in preparation for the release of IFN-γ and GM-CSF shield themselves from the potentially apoptotic effects of the former entrusting their survival to GM-SCF. In vitro phenotyping confirmed the selective surface expression of CD131 by Ag-activated CTLs and their increased proliferation upon exogenous administration of GM-CSF. Conclusion The selective responsiveness of Ag-activated CTLs to GM-CSF may provide an alternative explanation to the usefulness of this chemokine as an adjuvant for T cell aimed vaccines. Moreover, the selective expression of CD131 by Ag-activated CTLs proposes CD131 as a novel biomarker of Ag-dependent CTL activation.

  4. Plasma macrophage-derived chemokine (CCL22) and its receptor ...

    African Journals Online (AJOL)

    Ehab

    CCR. 4+ P. BT. L. %. Fig. 2B (In-between attacks). Figure 2. Positive correlations between the percentage of peripheral blood T lymphocytes expressing the chemokine CC receptor-4 (CCR4) and plasma levels of macrophage derived chemokine (MDC) among asthmatic children during acute attacks (Fig.2A) and after ...

  5. Chemokines and chemokine receptors expression in the lesions of patients with American cutaneous leishmaniasis

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    Nilka Luisa Diaz

    2013-06-01

    Full Text Available American cutaneous leishmaniasis (ACL presents distinct active clinical forms with different grades of severity, known as localised (LCL, intermediate (ICL and diffuse (DCL cutaneous leishmaniasis. LCL and DCL are associated with a polarised T-helper (Th1 and Th2 immune response, respectively, whereas ICL, or chronic cutaneous leishmaniasis, is associated with an exacerbated immune response and a mixed cytokine expression profile. Chemokines and chemokine receptors are involved in cellular migration and are critical in the inflammatory response. Therefore, we evaluated the expression of the chemokines CXCL10, CCL4, CCL8, CCL11 and CXCL8 and the chemokine receptors CCR3, CXCR3, CCR5 and CCR7 in the lesions of patients with different clinical forms of ACL using immunohistochemistry. LCL patients exhibited a high density of CXCL10+, CCL4+ and CCL8+ cells, indicating an important role for these chemokines in the local Th1 immune response and the migration of CXCR3+ cells. LCL patients showed a higher density of CCR7+ cells than ICL or DCL patients, suggesting major dendritic cell (DC migration to lymph nodes. Furthermore, DCL was associated with low expression levels of Th1-associated chemokines and CCL11+ epidermal DCs, which contribute to the recruitment of CCR3+ cells. Our findings also suggest an important role for epidermal cells in the induction of skin immune responses through the production of chemokines, such as CXCL10, by keratinocytes.

  6. Dysregulation of chemokine/chemokine receptor axes and NK cell tissue localization during diseases

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    Giovanni Bernardini

    2016-10-01

    Full Text Available ABSTRACTChemokines are small chemotactic molecules that play key roles in physiological and pathological conditions. Upon signaling via their specific receptors, chemokines regulate tissue mobilization and trafficking of a wide array of immune cells, including NK cells. Current research is focused in analyzing changes of chemokine/chemokine receptor expression during various diseases to interfere with pathological trafficking of cells, or to recruit selected cell types to specific tissues. NK cells are a heterogeneous lymphocyte population comprising several subsets endowed with distinct functional properties and mainly representing distinct stages of a linear development process. Because of their different functional potential, the type of subset that accumulates in a tissue drives the final outcome of NK cell-regulated immune response, leading to either protection or pathology. Correspondingly, chemokine receptors including CXCR4, CXCR3 and CX3CR1 are differentially expressed by NK cell subsets and their expression levels can be modulated during NK cell activation. This review will at first summarize the current knowledge on the contribution of chemokines to the localization and generation of NK cell subsets in homeostasis. How an inappropriate chemotactic response can lead to pathology and how chemokine targeting can therapeutically affect tissue recruitment/localization of distinct NK cell subsets will also be discussed.

  7. Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists

    Science.gov (United States)

    2016-08-01

    AWARD NUMBER: W81XWH-15 1-0252 TITLE: Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists PRINCIPAL INVESTIGATOR...14 Jul 2016 4. TITLE AND SUBTITLE Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists 5a. CONTRACT NUMBER 5b. GRANT...Center for Substance Abuse Research Lewis Katz School of Medicine at Temple University 3500 N, Broad Street Philadelphia, PA 19140 AND ADDRESS(ES) 8

  8. Selective Expression of CCR10 and CXCR3 by Circulating Human Herpes Simplex Virus-Specific CD8 T Cells.

    Science.gov (United States)

    Hensel, Michael T; Peng, Tao; Cheng, Anqi; De Rosa, Stephen C; Wald, Anna; Laing, Kerry J; Jing, Lichen; Dong, Lichun; Magaret, Amalia S; Koelle, David M

    2017-10-01

    Herpes simplex virus (HSV) infection is restricted to epithelial cells and neurons and is controlled by CD8 T cells. These cells both traffic to epithelial sites of recurrent lytic infection and to ganglia and persist at the dermal-epidermal junction for up to 12 weeks after lesion resolution. We previously showed that cutaneous lymphocyte-associated antigen (CLA), a functional E-selectin ligand (ESL), is selectively expressed on circulating HSV-2-specific CD8 T cells. CLA/ESL mediates adhesion of T cells to inflamed vascular endothelium. Later stages in T-cell homing involve chemokines (Ch) and lymphocyte chemokine receptors (ChR) for vascular wall arrest and diapedesis. Several candidate ChR have been implicated in skin homing. We measured cell surface ChR on HSV-specific human peripheral blood CD8 T cells and extended our studies to HSV-1. We observed preferential cell surface expression of CCR10 and CXCR3 by HSV-specific CD8 T cells compared to CD8 T cells specific for control viruses, Epstein-Barr virus (EBV) and cytomegalovirus (CMV), and compared to bulk memory CD8 T cells. CXCR3 ligand mRNA levels were selectively increased in skin biopsy specimens from persons with recurrent HSV-2, while the mRNA levels of the CCR10 ligand CCL27 were equivalent in lesion and control skin. Our data are consistent with a model in which CCL27 drives baseline recruitment of HSV-specific CD8 T cells expressing CCR10, while interferon-responsive CXCR3 ligands recruit additional cells in response to virus-driven inflammation. IMPORTANCE HSV-2 causes very localized recurrent infections in the skin and genital mucosa. Virus-specific CD8 T cells home to the site of recurrent infection and participate in viral clearance. The exit of T cells from the blood involves the use of chemokine receptors on the T-cell surface and chemokines that are present in infected tissue. In this study, circulating HSV-2-specific CD8 T cells were identified using specific fluorescent tetramer reagents

  9. Characterization of a novel single-chain bispecific antibody for retargeting of T cells to tumor cells via the TCR co-receptor CD8.

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    Irene Michalk

    Full Text Available There is currently growing interest in retargeting of effector T cells to tumor cells via bispecific antibodies (bsAbs. Usually, bsAbs are directed on the one hand to the CD3 complex of T cells and on the other hand to a molecule expressed on the surface of the target cell. A bsAb-mediated cross-linkage via CD3 leads to an activation of CD8+ T cells and consequently to killing of the target cells. In parallel, CD4+ T cells including TH1, TH2, TH17 cells and even regulatory T cells (Tregs will be activated as well. Cytokines produced by CD4+ T cells can contribute to severe side effects e. g. life-threatening cytokine storms and, thinking of the immunosupressive function of Tregs, can even be counterproductive. Therefore, we asked whether or not it is feasible to limit retargeting to CD8+ T cells e. g. via targeting of the co-receptor CD8 instead of CD3. In order to test for proof of concept, a novel bsAb with specificity for CD8 and a tumor-associated surface antigen was constructed. Interestingly, we found that pre-activated (but not freshly isolated CD8+ T cells can be retargeted via CD8-engaging bsAbs leading to an efficient lysis of target cells.

  10. Nonspecific CD8+T Cells and Dendritic Cells/Macrophages Participate in Formation of CD8+T Cell-Mediated Clusters against Malaria Liver-Stage Infection.

    Science.gov (United States)

    Akbari, Masoud; Kimura, Kazumi; Bayarsaikhan, Ganchimeg; Kimura, Daisuke; Miyakoda, Mana; Juriasingani, Smriti; Yuda, Masao; Amino, Rogerio; Yui, Katsuyuki

    2018-04-01

    CD8 + T cells are the major effector cells that protect against malaria liver-stage infection, forming clusters around Plasmodium -infected hepatocytes and eliminating parasites after a prolonged interaction with these hepatocytes. We aimed to investigate the roles of specific and nonspecific CD8 + T cells in cluster formation and protective immunity. To this end, we used Plasmodium berghei ANKA expressing ovalbumin as well as CD8 + T cells from transgenic mice expressing a T cell receptor specific for ovalbumin (OT-I) and CD8 + T cells specific for an unrelated antigen, respectively. While antigen-specific CD8 + T cells were essential for cluster formation, both antigen-specific and nonspecific CD8 + T cells joined the clusters. However, nonspecific CD8 + T cells did not significantly contribute to protective immunity. In the livers of infected mice, specific CD8 + T cells expressed high levels of CD25, compatible with a local, activated effector phenotype. In vivo imaging of the liver revealed that specific CD8 + T cells interact with CD11c + cells around infected hepatocytes. The depletion of CD11c + cells virtually eliminated the clusters in the liver, leading to a significant decrease in protection. These experiments reveal an essential role of hepatic CD11c + dendritic cells and presumably macrophages in the formation of CD8 + T cell clusters around Plasmodium -infected hepatocytes. Once cluster formation is triggered by parasite-specific CD8 + T cells, specific and unrelated activated CD8 + T cells join the clusters in a chemokine- and dendritic cell-dependent manner. Nonspecific CD8 + T cells seem to play a limited role in protective immunity against Plasmodium parasites. Copyright © 2018 American Society for Microbiology.

  11. Structural basis of ligand interaction with atypical chemokine receptor 3

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    Gustavsson, Martin; Wang, Liwen; van Gils, Noortje; Stephens, Bryan S.; Zhang, Penglie; Schall, Thomas J.; Yang, Sichun; Abagyan, Ruben; Chance, Mark R.; Kufareva, Irina; Handel, Tracy M.

    2017-01-18

    Chemokines drive cell migration through their interactions with seven-transmembrane (7TM) chemokine receptors on cell surfaces. The atypical chemokine receptor 3 (ACKR3) binds chemokines CXCL11 and CXCL12 and signals exclusively through β-arrestin-mediated pathways, without activating canonical G-protein signalling. This receptor is upregulated in numerous cancers making it a potential drug target. Here we collected over 100 distinct structural probes from radiolytic footprinting, disulfide trapping, and mutagenesis to map the structures of ACKR3:CXCL12 and ACKR3:small-molecule complexes, including dynamic regions that proved unresolvable by X-ray crystallography in homologous receptors. The data are integrated with molecular modelling to produce complete and cohesive experimentally driven models that confirm and expand on the existing knowledge of the architecture of receptor:chemokine and receptor:small-molecule complexes. Additionally, we detected and characterized ligand-induced conformational changes in the transmembrane and intracellular regions of ACKR3 that elucidate fundamental structural elements of agonism in this atypical receptor.

  12. Human G protein-coupled receptor GPR-9-6/CC chemokine receptor 9 is selectively expressed on intestinal homing T lymphocytes, mucosal lymphocytes, and thymocytes and is required for thymus-expressed chemokine-mediated chemotaxis.

    Science.gov (United States)

    Zabel, B A; Agace, W W; Campbell, J J; Heath, H M; Parent, D; Roberts, A I; Ebert, E C; Kassam, N; Qin, S; Zovko, M; LaRosa, G J; Yang, L L; Soler, D; Butcher, E C; Ponath, P D; Parker, C M; Andrew, D P

    1999-11-01

    TECK (thymus-expressed chemokine), a recently described CC chemokine expressed in thymus and small intestine, was found to mediate chemotaxis of human G protein-coupled receptor GPR-9-6/L1.2 transfectants. This activity was blocked by anti-GPR-9-6 monoclonal antibody (mAb) 3C3. GPR-9-6 is expressed on a subset of memory alpha4beta7(high) intestinal trafficking CD4 and CD8 lymphocytes. In addition, all intestinal lamina propria and intraepithelial lymphocytes express GPR-9-6. In contrast, GPR-9-6 is not displayed on cutaneous lymphocyte antigen-positive (CLA(+)) memory CD4 and CD8 lymphocytes, which traffic to skin inflammatory sites, or on other systemic alpha4beta7(-)CLA(-) memory CD4/CD8 lymphocytes. The majority of thymocytes also express GPR-9-6, but natural killer cells, monocytes, eosinophils, basophils, and neutrophils are GPR-9-6 negative. Transcripts of GPR-9-6 and TECK are present in both small intestine and thymus. Importantly, the expression profile of GPR-9-6 correlates with migration to TECK of blood T lymphocytes and thymocytes. As migration of these cells is blocked by anti-GPR-9-6 mAb 3C3, we conclude that GPR-9-6 is the principal chemokine receptor for TECK. In agreement with the nomenclature rules for chemokine receptors, we propose the designation CCR-9 for GPR-9-6. The selective expression of TECK and GPR-9-6 in thymus and small intestine implies a dual role for GPR-9-6/CCR-9, both in T cell development and the mucosal immune response.

  13. A highly restricted T-cell receptor dominates the CD8+ T-cell response to parvovirus B19 infection in HLA-A*2402-positive individuals

    DEFF Research Database (Denmark)

    Kasprowicz, V; Isa, Adiba; Jeffery, K

    2006-01-01

    Six of seven HLA-A*2402-positive individuals with acute parvovirus B19 infections made vigorous CD8-positive cytotoxic T-cell (CTL) responses to the viral epitope FYTPLADQF. All responders showed highly focused T-cell receptor (TCR) usage, using almost exclusively BV5.1. The BV5.1 TCR dominated...

  14. Programmed death-1 expression on HIV-1-specific CD8+ T cells is shaped by epitope specificity, T-cell receptor clonotype usage and antigen load

    DEFF Research Database (Denmark)

    Kløverpris, Henrik N; McGregor, Reuben; McLaren, James E

    2014-01-01

    of differentiation on HIV-1-specific CD8+ T-cell populations(n = 128) spanning 11 different epitope targets. RESULTS: Expression levels of PD-1, but not CD244 or LAG-3, varied substantially across epitope specificities both within and between individuals. Differential expression of PD-1 on T-cell receptor (TCR...

  15. Interleukin-9 receptor α chain mRNA formation in CD8+ T cells producing anti-human immunodeficiency virus type 1 substance(s)

    International Nuclear Information System (INIS)

    Hossain, M.M.; Tsuchie, H.; Detorio, M.A.; Shirono, H.; Hara, C.; Nishimoto, A.; Saji, A.; Koga, J.; Takata, N.; Maniar, J.K.; Saple, D.G.; Taniguchi, K.; Kageyama, S.; Ichimura, H.; Kurimura, T.

    1998-01-01

    A search for gene(s) associated with anti-human immunodeficiency virus type 1 (HIV-l) activity of CD8 + T cells was attempted using molecular cloning and the relation between the anti-HIV activity of CD8 + T cells and the interleukin-9 receptor a chain (IL-9R-α) mRNA expression from the cDNA clones obtained was examined. The anti-HIV-l activity of CD8 + T cell culture supernatants was assessed by measuring the level of HIV-l replication in a CD4 + T cell line transfected with an infectious HIV-l DNA clone. IL-9R-a mRNA was assayed by reverse transcriptase-polymerase chain reaction (RT-PCR). Of 5 cases showing high level of anti-HIV-l activity (more than 80% suppression of HIV-l replication), the mRNA was detected in 4 cases. Of 10 cases showing low level of anti-HIV-l activity (less than 80% suppression of HIV-l replication), the mRNA was detected in one case. Soluble recombinant human IL-9 receptor (rhIL-9sR) did not suppress HIV-l replication at a concentration of 1 μg/ml. These data suggest that the IL-9R-a mRNA formation in CD8 + T cells may correlate with and play some role in the anti-HIV-l activity of CD8+ T cells from HIV-l-infected individuals. Key words: CD8+ T cells; anti-HIV-l activity; cytokines; interleukin-9 receptor (authors)

  16. Enhanced Chemokine Receptor Expression on Leukocytes of Patients with Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    David Goldeck

    Full Text Available Although primarily a neurological complaint, systemic inflammation is present in Alzheimer's Disease, with higher than normal levels of proinflammatory cytokines and chemokines in the periphery as well as the brain. A gradient of these factors may enhance recruitment of activated immune cells into the brain via chemotaxis. Here, we investigated the phenotypes of circulating immune cells in AD patients with multi-colour flow cytometry to determine whether their expression of chemokine receptors is consistent with this hypothesis. In this study, we confirmed our previously reported data on the shift of early- to late-differentiated CD4+ T-cells in AD patients. The percentage of cells expressing CD25, a marker of acute T-cell activation, was higher in patients than in age-matched controls, and percentages of CCR6+ cells were elevated. This chemokine receptor is primarily expressed on pro-inflammatory memory cells and Th17 cells. The proportion of cells expressing CCR4 (expressed on Th2 cells and CCR5 (Th1 cells and dendritic cells was also greater in patients, and was more pronounced on CD4+ than CD8+ T-cells. These findings allow a more detailed insight into the systemic immune status of patients with Alzheimer's disease and suggest possible novel targets for immune therapy.

  17. Differential Expression of Chemokine Receptors and their Roles in Cancer Imaging

    International Nuclear Information System (INIS)

    Nimmagadda, Sridhar

    2012-01-01

    Chemokine/chemokine receptor interactions play diverse roles in cell migration and homeostasis. Emerging evidence suggests that cancer cells co-opt chemokine networks for survival, proliferation, immune evasion, and metastasis. Most of the chemokine receptors are reported to be involved in tumor progression. Given their extensive implication in cancer progression, several chemokine receptor/ligand axes are considered as potential therapeutic targets. This review provides a survey of chemokine receptor expression in cancer and evaluates the potential of chemokine receptor imaging as a tool for molecular characterization of cancer.

  18. Distinct chemokine receptor and cytokine expression profile in secondary progressive MS

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F

    2001-01-01

    Chemokines, small chemotactic cytokines, have been implicated in active relapsing-remitting MS (RRMS). However, the role of chemokines and chemokine receptors has not been specifically studied in secondary progressive MS (SPMS).......Chemokines, small chemotactic cytokines, have been implicated in active relapsing-remitting MS (RRMS). However, the role of chemokines and chemokine receptors has not been specifically studied in secondary progressive MS (SPMS)....

  19. Peripheral tissue homing receptor control of naïve, effector, and memory CD8 T cell localization in lymphoid and non-lymphoid tissues.

    Science.gov (United States)

    Brinkman, C Colin; Peske, J David; Engelhard, Victor Henry

    2013-01-01

    T cell activation induces homing receptors that bind ligands on peripheral tissue vasculature, programing movement to sites of infection and injury. There are three major types of CD8 effector T cells based on homing receptor expression, which arise in distinct lymphoid organs. Recent publications indicate that naïve, effector, and memory T cell migration is more complex than once thought; while many effectors enter peripheral tissues, some re-enter lymph nodes (LN), and contain central memory precursors. LN re-entry can depend on CD62L or peripheral tissue homing receptors. Memory T cells in LN tend to express the same homing receptors as their forebears, but often are CD62Lneg. Homing receptors also control CD8 T cell tumor entry. Tumor vasculature has low levels of many peripheral tissue homing receptor ligands, but portions of it resemble high endothelial venules (HEV), enabling naïve T cell entry, activation, and subsequent effector activity. This vasculature is associated with positive prognoses in humans, suggesting it may sustain ongoing anti-tumor responses. These findings reveal new roles for homing receptors expressed by naïve, effector, and memory CD8 T cells in controlling entry into lymphoid and non-lymphoid tissues.

  20. Impaired virus control and severe CD8+ T-cell-mediated immunopathology in chimeric mice deficient in gamma interferon receptor expression on both parenchymal and hematopoietic cells

    DEFF Research Database (Denmark)

    Henrichsen, Pernille; Bartholdy, Christina; Christensen, Jan Pravsgaard

    2005-01-01

    virus completely lack the ability to control the infection and develop severe wasting disease. Further, the study shows that IFN-gamma receptor expression on parenchymal cells in the viscera is more important for virus control than IFN-gamma receptor expression on bone marrow-derived cells.......Bone marrow chimeras were used to determine the cellular target(s) for the antiviral activity of gamma interferon (IFN-gamma). By transfusing such mice with high numbers of naive virus-specific CD8(+) T cells, a system was created in which the majority of virus-specific CD8(+) T cells would...... be capable of responding to IFN-gamma, but expression of the relevant receptor on non-T cells could be experimentally controlled. Only when the IFN-gamma receptor is absent on both radioresistant parenchymal and bone marrow-derived cells will chimeric mice challenged with a highly invasive, noncytolytic...

  1. Chemokine-Ligands/Receptors: Multiplayers in Traumatic Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Friederike Knerlich-Lukoschus

    2015-01-01

    Full Text Available Spinal cord injury (SCI results in complex posttraumatic sequelae affecting the whole neuraxis. Due to its involvement in varied neuromodulatory processes, the chemokine-ligand/receptor-network is a key element of secondary lesion cascades induced by SCI. This review will provide a synopsis of chemokine-ligand/receptor-expression along the whole neuraxis after traumatic spinal cord (sc insults on basis of recent in vivo and in vitro findings in a SCI paradigm of thoracic force-defined impact lesions (Infinite Horizon Impactor in adult rats. Analyses of chemokine-ligand/receptor-expression at defined time points after sc lesion of different severity grades or sham operation revealed that these inflammatory mediators are induced in distinct anatomical sc regions and in thalamic nuclei, periaqueductal grey, and hippocampal structures in the brain. Cellular and anatomical expression profiles together with colocalization/expression of neural stem/progenitor cell markers in adult sc stem cells niches or with pain-related receptors and mediators in dorsal horns, dorsal columns, and pain-processing brain areas support the notion that chemokines are involved in distinct cascades underlying clinical posttraumatic impairments and syndromes. These aspects and their implication in concepts of tailored SCI treatment are reviewed in the context of the recent literature on chemokine-ligand/receptor involvement in complex secondary lesion cascades.

  2. Toll-Like Receptor 2 Targeted Rectification of Impaired CD8⁺ T Cell Functions in Experimental Leishmania donovani Infection Reinstates Host Protection.

    Directory of Open Access Journals (Sweden)

    Syamdas Bandyopadhyay

    Full Text Available Leishmania donovani, a protozoan parasite, causes the disease visceral leishmanisis (VL, characterized by inappropriate CD8+ T-cell activation. Therefore, we examined whether the Toll-like Receptor 2 (TLR2 ligand Ara-LAM, a cell wall glycolipid from non-pathogenic Mycobacterium smegmatis, would restore CD8+ T-cell function during VL. We observed that by efficient upregulation of TLR2 signaling-mediated NF-κB translocation and MAPK signaling in CD8+ T-cells (CD25+CD28+IL-12R+IFN-γR+, Ara-LAM triggered signaling resulted in the activation of T-bet, which in turn, induced transcription favourable histone modification at the IFN-γ, perforin, granzyme-B promoter regions in CD8+ T-cells. Thus, we conclude that Ara-LAM induced efficient activation of effector CD8+ T-cells by upregulating the expression of IFN-γ, perforin and granzyme-B in an NF-κB and MAPK induced T-bet dependent manner in VL.

  3. Krüppel-like factor KLF10 regulates transforming growth factor receptor II expression and TGF-β signaling in CD8+ T lymphocytes.

    Science.gov (United States)

    Papadakis, Konstantinos A; Krempski, James; Reiter, Jesse; Svingen, Phyllis; Xiong, Yuning; Sarmento, Olga F; Huseby, April; Johnson, Aaron J; Lomberk, Gwen A; Urrutia, Raul A; Faubion, William A

    2015-03-01

    KLF10 has recently elicited significant attention as a transcriptional regulator of transforming growth factor-β1 (TGF-β1) signaling in CD4(+) T cells. In the current study, we demonstrate a novel role for KLF10 in the regulation of TGF-β receptor II (TGF-βRII) expression with functional relevance in antiviral immune response. Specifically, we show that KLF10-deficient mice have an increased number of effector/memory CD8(+) T cells, display higher levels of the T helper type 1 cell-associated transcription factor T-bet, and produce more IFN-γ following in vitro stimulation. In addition, KLF10(-/-) CD8(+) T cells show enhanced proliferation in vitro and homeostatic proliferation in vivo. Freshly isolated CD8(+) T cells from the spleen of adult mice express lower levels of surface TGF-βRII (TβRII). Congruently, in vitro activation of KLF10-deficient CD8(+) T cells upregulate TGF-βRII to a lesser extent compared with wild-type (WT) CD8(+) T cells, which results in attenuated Smad2 phosphorylation following TGF-β1 stimulation compared with WT CD8(+) T cells. Moreover, we demonstrate that KLF10 directly binds to the TGF-βRII promoter in T cells, leading to enhanced gene expression. In vivo viral infection with Daniel's strain Theiler's murine encephalomyelitis virus (TMEV) also led to lower expression of TGF-βRII among viral-specific KLF10(-/-) CD8(+) T cells and a higher percentage of IFN-γ-producing CD8(+) T cells in the spleen. Collectively, our data reveal a critical role for KLF10 in the transcriptional activation of TGF-βRII in CD8(+) T cells. Thus, KLF10 regulation of TGF-βRII in this cell subset may likely play a critical role in viral and tumor immune responses for which the integrity of the TGF-β1/TGF-βRII signaling pathway is crucial. Copyright © 2015 the American Physiological Society.

  4. Virally encoded chemokines and chemokine receptors in the role of viral infections

    DEFF Research Database (Denmark)

    Holst, Peter J; Lüttichau, Hans R; Schwartz, Thue W

    2003-01-01

    are the acquisition and modification of host-encoded chemokines and chemokine receptors. The described viral molecules leave nothing to chance and have thoroughly and efficiently corrupted the host immune system. Through this process viruses have identified key molecules in antiviral responses by their inhibition...... of these or potent ways to alter an efficient antiviral response to a weak Th2-driven response. Examples here are the chemokine scavenging by US28, attractance of Th2 cells and regulatory cells by vMIP1-3 and the selective engaging of CCR8 by MC148. Important insights into viral pathology and possible targets......Large DNA viruses such as pox- and in particular herpesviruses are notorious in their ability to evade the immune system and to be maintained in the general population. Based on the accumulated knowledge reviewed in this study it is evident that important mechanisms of these actions...

  5. Truncation of CXCL12 by CD26 reduces its CXC chemokine receptor 4- and atypical chemokine receptor 3-dependent activity on endothelial cells and lymphocytes

    DEFF Research Database (Denmark)

    Janssens, Rik; Mortier, Anneleen; Boff, Daiane

    2017-01-01

    The chemokine CXCL12 or stromal cell-derived factor 1/SDF-1 attracts hematopoietic progenitor cells and mature leukocytes through the G protein-coupled CXC chemokine receptor 4 (CXCR4). In addition, it interacts with atypical chemokine receptor 3 (ACKR3 or CXCR7) and glycosaminoglycans. CXCL12 ac...

  6. Expression of type 3 complement receptor on activated CD8+ T cells facilitates homing to inflammatory sites

    DEFF Research Database (Denmark)

    Nielsen, H V; Christensen, Jan Pravsgaard; Andersson, E C

    1994-01-01

    /macrophages and CD8+ cells, the majority of which are CD11b+. Adoptive transfer experiments involving i.v. transplantation of Ag-primed donor cells revealed that preincubation of the cells with 5C6 delayed the virus-specific delayed-type hypersensitivity reaction under conditions in which the recipient delivered...... that anti-CR3 treatment inhibits extravasation of both the Ag-specific and the nonspecific cellular components of the lymphocytic choriomeningitis virus-induced, CD8+ cell-dependent inflammatory reaction. Thus, expression of CR3 seems to facilitate T cell homing to sites of inflammation....

  7. CX3CL1/CX3CR1 and CCL2/CCR2 Chemokine/Chemokine Receptor Complex in Patients with AMD

    DEFF Research Database (Denmark)

    Falk, Mads Krüger; Singh, Amardeep; Faber, Carsten

    2014-01-01

    PURPOSE: The chemokine receptors CX3CR1 and CCR2 have been implicated in the development of age-related macular degeneration (AMD). The evidence is mainly derived from experimental cell studies and murine models of AMD. The purpose of this study was to investigate the association between expression...... of CX3CR1 and CCR2 on different leukocyte subsets and AMD. Furthermore we measured the plasma levels of ligands CX3CL1 and CCL2. METHODS: Patients attending our department were asked to participate in the study. The diagnosis of AMD was based on clinical examination and multimodal imaging techniques...... positive correlation between CCR2 and CX3CR1 expression on CD8+ cells (r = 0.727, p = 0.0001). We found no difference in plasma levels of CX3CL1 and CCL2 among the groups. CONCLUSIONS: Our results show a down regulation of CX3CR1 on CD8+ cells; this correlated to a low expression of CCR2 on CD8+ cells...

  8. A Toll-like receptor 2 agonist-fused antigen enhanced antitumor immunity by increasing antigen presentation and the CD8 memory T cells population.

    Science.gov (United States)

    Wu, Chiao-Chieh; Liu, Shih-Jen; Chen, Hsin-Wei; Shen, Kuan-Yin; Leng, Chih-Hsiang

    2016-05-24

    The induction of long-lived effector CD8+ T cells is key to the development of efficient cancer vaccines. In this study, we demonstrated that a Toll-like receptor 2 (TLR2) agonist-fused antigen increased antigen presentation via TLR2 signaling and induced effector memory-like CD8+ T cells against cancer after immunization. The N-terminus of ovalbumin (OVA) was biologically fused with a bacterial lipid moiety TLR2 agonist to produce a recombinant lipidated ovalbumin (rlipo-OVA). We demonstrated that rlipo-OVA activated bone marrow-derived dendritic cells (BM-DCs) maturation and increased antigen presentation by major histocompatibility complex (MHC) class I via TLR2. After immunization, rlipo-OVA skewed the immune response towards T helper (Th) 1 and induced OVA-specific cytotoxic T lymphocyte (CTL) responses. Moreover, immunization with rlipo-OVA induced higher numbers of effector memory (CD44+CD62L-) CD8+ T cells compared with recombinant ovalbumin (rOVA) alone or rOVA mixed with the TLR2 agonist Pam3CSK4. Accordingly, the CD27+CD43+ effector memory CD8+ T cells expressed high levels of the long-lived CD127 marker. The administration of rlipo-OVA could inhibit tumor growth, but the anti-tumor effects were lost after the depletion of CD8 or CD127 cells in vivo. These findings suggested that the TLR2 agonist-fused antigen induced long-lived memory CD8+ T cells for efficient cancer therapy.

  9. Autoreactive effector/memory CD4+ and CD8+ T cells infiltrating grafted and endogenous islets in diabetic NOD mice exhibit similar T cell receptor usage.

    Directory of Open Access Journals (Sweden)

    Ramiro Diz

    Full Text Available Islet transplantation provides a "cure" for type 1 diabetes but is limited in part by recurrent autoimmunity mediated by β cell-specific CD4(+ and CD8(+ T cells. Insight into the T cell receptor (TCR repertoire of effector T cells driving recurrent autoimmunity would aid the development of immunotherapies to prevent islet graft rejection. Accordingly, we used a multi-parameter flow cytometry strategy to assess the TCR variable β (Vβ chain repertoires of T cell subsets involved in autoimmune-mediated rejection of islet grafts in diabetic NOD mouse recipients. Naïve CD4(+ and CD8(+ T cells exhibited a diverse TCR repertoire, which was similar in all tissues examined in NOD recipients including the pancreas and islet grafts. On the other hand, the effector/memory CD8(+ T cell repertoire in the islet graft was dominated by one to four TCR Vβ chains, and specific TCR Vβ chain usage varied from recipient to recipient. Similarly, islet graft- infiltrating effector/memory CD4(+ T cells expressed a limited number of prevalent TCR Vβ chains, although generally TCR repertoire diversity was increased compared to effector/memory CD8(+ T cells. Strikingly, the majority of NOD recipients showed an increase in TCR Vβ12-bearing effector/memory CD4(+ T cells in the islet graft, most of which were proliferating, indicating clonal expansion. Importantly, TCR Vβ usage by effector/memory CD4(+ and CD8(+ T cells infiltrating the islet graft exhibited greater similarity to the repertoire found in the pancreas as opposed to the draining renal lymph node, pancreatic lymph node, or spleen. Together these results demonstrate that effector/memory CD4(+ and CD8(+ T cells mediating autoimmune rejection of islet grafts are characterized by restricted TCR Vβ chain usage, and are similar to T cells that drive destruction of the endogenous islets.

  10. T cell receptor-mediated activation is a potent inducer of macroautophagy in human CD8(+)CD28(+) T cells but not in CD8(+)CD28(-) T cells

    NARCIS (Netherlands)

    Arnold, Christoph R; Pritz, Theresa; Brunner, Stefan; Knabb, Carina; Salvenmoser, Willi; Holzwarth, Birgit; Thedieck, Kathrin; Grubeck-Loebenstein, Beatrix

    A key feature of the aged human immune system is the accumulation of highly differentiated CD8(+)CD28(-) T cells, a phenomenon that negatively influences immune function in the elderly. However, the mechanisms that regulate survival or death of CD8(+)CD28(-) T cells remain incompletely understood.

  11. Normalized Synergy Predicts That CD8 Co-Receptor Contribution to T Cell Receptor (TCR and pMHC Binding Decreases As TCR Affinity Increases in Human Viral-Specific T Cells

    Directory of Open Access Journals (Sweden)

    Chad M. Williams

    2017-07-01

    Full Text Available The discovery of naturally occurring T cell receptors (TCRs that confer specific, high-affinity recognition of pathogen and cancer-associated antigens remains a major goal in cellular immunotherapies. The contribution of the CD8 co-receptor to the interaction between the TCR and peptide-bound major histocompatibility complex (pMHC has previously been correlated with the activation and responsiveness of CD8+ T cells. However, these studies have been limited to model systems of genetically engineered hybridoma TCRs or transgenic mouse TCRs against either a single epitope or an array of altered peptide ligands. CD8 contribution in a native human antigen-specific T cell response remains elusive. Here, using Hepatitis C Virus-specific precursor CTLs spanning a large range of TCR affinities, we discovered that the functional responsiveness of any given TCR correlated with the contribution of CD8 to TCR/pMHC binding. Furthermore, we found that CD8 contribution to TCR/pMHC binding in the two-dimensional (2D system was more accurately reflected by normalized synergy (CD8 cooperation normalized by total TCR/pMHC bonds rather than synergy (total CD8 cooperation alone. While synergy showed an increasing trend with TCR affinity, normalized synergy was demonstrated to decrease with the increase of TCR affinity. Critically, normalized synergy was shown to correlate with CTL functionality and peptide sensitivity, corroborating three-dimensional (3D analysis of CD8 contribution with respect to TCR affinity. In addition, we identified TCRs that were independent of CD8 for TCR/pMHC binding. Our results resolve the current discrepancy between 2D and 3D analysis on CD8 contribution to TCR/pMHC binding, and demonstrate that naturally occurring high-affinity TCRs are more capable of CD8-independent interactions that yield greater functional responsiveness even with CD8 blocking. Taken together, our data suggest that addition of the normalized synergy parameter to our

  12. Normalized Synergy Predicts That CD8 Co-Receptor Contribution to T Cell Receptor (TCR) and pMHC Binding Decreases As TCR Affinity Increases in Human Viral-Specific T Cells.

    Science.gov (United States)

    Williams, Chad M; Schonnesen, Alexandra A; Zhang, Shu-Qi; Ma, Ke-Yue; He, Chenfeng; Yamamoto, Tori; Eckhardt, S Gail; Klebanoff, Christopher A; Jiang, Ning

    2017-01-01

    The discovery of naturally occurring T cell receptors (TCRs) that confer specific, high-affinity recognition of pathogen and cancer-associated antigens remains a major goal in cellular immunotherapies. The contribution of the CD8 co-receptor to the interaction between the TCR and peptide-bound major histocompatibility complex (pMHC) has previously been correlated with the activation and responsiveness of CD8 + T cells. However, these studies have been limited to model systems of genetically engineered hybridoma TCRs or transgenic mouse TCRs against either a single epitope or an array of altered peptide ligands. CD8 contribution in a native human antigen-specific T cell response remains elusive. Here, using Hepatitis C Virus-specific precursor CTLs spanning a large range of TCR affinities, we discovered that the functional responsiveness of any given TCR correlated with the contribution of CD8 to TCR/pMHC binding. Furthermore, we found that CD8 contribution to TCR/pMHC binding in the two-dimensional (2D) system was more accurately reflected by normalized synergy (CD8 cooperation normalized by total TCR/pMHC bonds) rather than synergy (total CD8 cooperation) alone. While synergy showed an increasing trend with TCR affinity, normalized synergy was demonstrated to decrease with the increase of TCR affinity. Critically, normalized synergy was shown to correlate with CTL functionality and peptide sensitivity, corroborating three-dimensional (3D) analysis of CD8 contribution with respect to TCR affinity. In addition, we identified TCRs that were independent of CD8 for TCR/pMHC binding. Our results resolve the current discrepancy between 2D and 3D analysis on CD8 contribution to TCR/pMHC binding, and demonstrate that naturally occurring high-affinity TCRs are more capable of CD8-independent interactions that yield greater functional responsiveness even with CD8 blocking. Taken together, our data suggest that addition of the normalized synergy parameter to our previously

  13. Enhanced Effector Function of CD8+ T Cells From Healthy Controls and HIV-Infected Patients Occurs Through Thrombin Activation of Protease-Activated Receptor 1

    Science.gov (United States)

    Hurley, Amanda; Smith, Mindy; Karpova, Tatiana; Hasley, Rebecca B.; Belkina, Natalya; Shaw, Stephen; Balenga, Nariman; Druey, Kirk M.; Nickel, Erin; Packard, Beverly; Imamichi, Hiromi; Hu, Zonghui; Follmann, Dean; McNally, James; Higgins, Jeanette; Sneller, Michael; Lane, H. Clifford; Catalfamo, Marta

    2013-01-01

    Disruption of vascular integrity by trauma and other tissue insults leads to inflammation and activation of the coagulation cascade. The serine protease thrombin links these 2 processes. The proinflammatory function of thrombin is mediated by activation of protease-activated receptor 1 (PAR-1). We found that peripheral blood effector memory CD4+ and CD8+ T lymphocytes expressed PAR-1 and that expression was increased in CD8+ T cells from human immunodeficiency virus (HIV)–infected patients. Thrombin enhanced cytokine secretion in CD8+ T cells from healthy controls and HIV-infected patients. In addition, thrombin induced chemokinesis, but not chemotaxis, of CD8+ T cells, which led to structural changes, including cell polarization and formation of a structure rich in F-actin and phosphorylated ezrin-radexin-moesin proteins. These findings suggest that thrombin mediates cross-talk between the coagulation system and the adaptive immune system at sites of vascular injury through increased T-cell motility and production of proinflammatory cytokines. PMID:23204166

  14. Enhanced effector function of CD8(+) T cells from healthy controls and HIV-infected patients occurs through thrombin activation of protease-activated receptor 1.

    Science.gov (United States)

    Hurley, Amanda; Smith, Mindy; Karpova, Tatiana; Hasley, Rebecca B; Belkina, Natalya; Shaw, Stephen; Balenga, Nariman; Druey, Kirk M; Nickel, Erin; Packard, Beverly; Imamichi, Hiromi; Hu, Zonghui; Follmann, Dean; McNally, James; Higgins, Jeanette; Sneller, Michael; Lane, H Clifford; Catalfamo, Marta

    2013-02-15

    Disruption of vascular integrity by trauma and other tissue insults leads to inflammation and activation of the coagulation cascade. The serine protease thrombin links these 2 processes. The proinflammatory function of thrombin is mediated by activation of protease-activated receptor 1 (PAR-1). We found that peripheral blood effector memory CD4(+) and CD8(+) T lymphocytes expressed PAR-1 and that expression was increased in CD8(+) T cells from human immunodeficiency virus (HIV)-infected patients. Thrombin enhanced cytokine secretion in CD8(+) T cells from healthy controls and HIV-infected patients. In addition, thrombin induced chemokinesis, but not chemotaxis, of CD8(+) T cells, which led to structural changes, including cell polarization and formation of a structure rich in F-actin and phosphorylated ezrin-radexin-moesin proteins. These findings suggest that thrombin mediates cross-talk between the coagulation system and the adaptive immune system at sites of vascular injury through increased T-cell motility and production of proinflammatory cytokines.

  15. Chemokine receptor CCR5 in interferon-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Kristiansen, Thomas Birk; Wittenhagen, P

    2007-01-01

    OBJECTIVE: To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta). METHODS: The CCR5 Delta32 allele and a CCR5 promoter polymorphism associated with cell surface expression of CCR5 were...

  16. T cell antigen receptor expression by subsets of Ly-2-L3T4- (CD8-CD4-) thymocytes

    DEFF Research Database (Denmark)

    Wilson, A; Ewing, T; Owens, T

    1988-01-01

    The V beta 8-specific mAb F23.1 and KJ16 were used as fluorescent stains to test for TCR expression on the surface of subpopulations of early, CD4-CD8- (L3T4-Ly-2-) thymocytes from adult CBA mice. A surprisingly high proportion (27%) of Ly-2-L3T4- thymocytes were strongly F23.1 and KJ16 positive...

  17. Chemokine receptor expression on B cells and effect of interferon-beta in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Roed, Hanne; Sellebjerg, Finn

    2002-01-01

    We investigated the B-cell expression of chemokine receptors CXCR3, CXCR5 and CCR5 in the blood and cerebrospinal fluid (CSF) from patients in relapse of multiple sclerosis (MS) and in neurological controls. Chemokine receptor expression was also studied in interferon-beta-treated patients with r......, and chemokine receptor expression was not affected by interferon-beta treatment....

  18. Isolated receptor binding domains of HTLV-1 and HTLV-2 envelopes bind Glut-1 on activated CD4+ and CD8+ T cells

    Science.gov (United States)

    Kinet, Sandrina; Swainson, Louise; Lavanya, Madakasira; Mongellaz, Cedric; Montel-Hagen, Amélie; Craveiro, Marco; Manel, Nicolas; Battini, Jean-Luc; Sitbon, Marc; Taylor, Naomi

    2007-01-01

    Background We previously identified the glucose transporter Glut-1, a member of the multimembrane-spanning facilitative nutrient transporter family, as a receptor for both HTLV-1 and HTLV-2. However, a recent report concluded that Glut-1 cannot serve as a receptor for HTLV-1 on CD4 T cells: This was based mainly on their inability to detect Glut-1 on this lymphocyte subset using the commercial antibody mAb1418. It was therefore of significant interest to thoroughly assess Glut-1 expression on CD4 and CD8 T cells, and its association with HTLV-1 and -2 envelope binding. Results As previously reported, ectopic expression of Glut-1 but not Glut-3 resulted in significantly augmented binding of tagged proteins harboring the receptor binding domains of either HTLV-1 or HTLV-2 envelope glycoproteins (H1RBD or H2RBD). Using antibodies raised against the carboxy-terminal peptide of Glut-1, we found that Glut-1 expression was significantly increased in both CD4 and CD8 cells following TCR stimulation. Corresponding increases in the binding of H1RBD as well as H2RBD, not detected on quiescent T cells, were observed following TCR engagement. Furthermore, increased Glut-1 expression was accompanied by a massive augmentation in glucose uptake in TCR-stimulated CD4 and CD8 lymphocytes. Finally, we determined that the apparent contradictory results obtained by Takenouchi et al were due to their monitoring of Glut-1 with a mAb that does not bind cells expressing endogenous Glut-1, including human erythrocytes that harbor 300,000 copies per cell. Conclusion Transfection of Glut-1 directly correlates with the capacities of HTLV-1 and HTLV-2 envelope-derived ligands to bind cells. Moreover, Glut-1 is induced by TCR engagement, resulting in massive increases in glucose uptake and binding of HTLV-1 and -2 envelopes to both CD4 and CD8 T lymphocytes. Therefore, Glut-1 is a primary binding receptor for HTLV-1 and HTLV-2 envelopes on activated CD4 as well as CD8 lymphocytes. PMID:17504522

  19. Expression of type 3 complement receptor on activated CD8+ T cells facilitates homing to inflammatory sites

    DEFF Research Database (Denmark)

    Nielsen, H V; Christensen, Jan Pravsgaard; Andersson, E C

    1994-01-01

    -cell extravasation at inflammatory foci. The in vivo administration of 5C6 significantly reduced the severity of the T cell-mediated meningitis induced by intracerebral inoculation of lymphocytic choriomeningitis virus. FACS analysis of the inflammatory exudate showed that this consists of monocytes...... that anti-CR3 treatment inhibits extravasation of both the Ag-specific and the nonspecific cellular components of the lymphocytic choriomeningitis virus-induced, CD8+ cell-dependent inflammatory reaction. Thus, expression of CR3 seems to facilitate T cell homing to sites of inflammation....

  20. Inhibition of T Cell Receptor Expression and Function in Immature CD4+CD8+ Cells by CD4

    Science.gov (United States)

    1990-09-28

    8217 SYNIOL Phyllis Blum, Information Services Division 0L-295-2188 IsD/ADMIN/NNRI DD FORM 1473, 84 MAR 83 APR ecoiton may oe usea until exnaulted...TCR surface expres- determined by electrophoresis of detergent-solubilized cell sion, decreased TCR- phosphorylation, or lvsates and immunoblotting...MAb to CI)3t (A) Purified B6 CD4’CD8’ thvlmocvltcs were SDS-polvacvlaxnide gel electrophoresis (SDS- (MAb 145-2C01), 13% SDS-PAGE in reducing cultured

  1. What Do Structures Tell Us About Chemokine Receptor Function and Antagonism?

    Energy Technology Data Exchange (ETDEWEB)

    Kufareva, Irina; Gustavsson, Martin; Zheng, Yi; Stephens, Bryan S.; Handel, Tracy M. (UCSD)

    2017-05-22

    Chemokines and their cell surface G protein–coupled receptors are critical for cell migration, not only in many fundamental biological processes but also in inflammatory diseases and cancer. Recent X-ray structures of two chemokines complexed with full-length receptors provided unprecedented insight into the atomic details of chemokine recognition and receptor activation, and computational modeling informed by new experiments leverages these insights to gain understanding of many more receptor:chemokine pairs. In parallel, chemokine receptor structures with small molecules reveal the complicated and diverse structural foundations of small molecule antagonism and allostery, highlight the inherent physicochemical challenges of receptor:chemokine interfaces, and suggest novel epitopes that can be exploited to overcome these challenges. The structures and models promote unique understanding of chemokine receptor biology, including the interpretation of two decades of experimental studies, and will undoubtedly assist future drug discovery endeavors.

  2. CD8 T-cell induction against vascular endothelial growth factor receptor 2 by Salmonella for vaccination purposes against a murine melanoma.

    Directory of Open Access Journals (Sweden)

    Stefan Jellbauer

    Full Text Available The Salmonella type III secretion system (T3SS efficiently translocates heterologous proteins into the cytosol of eukaryotic cells. This leads to an antigen-specific CD8 T-cell induction in mice orally immunized with recombinant Salmonella. Recently, we have used Salmonella's T3SS as a prophylactic and therapeutic intervention against a murine fibrosarcoma. In this study, we constructed a recombinant Salmonella strain translocating the immunogenic H-2D(b-specific CD8 T-cell epitope VILTNPISM (KDR2 from the murine vascular endothelial growth factor receptor 2 (VEGFR2. VEGFR2 is a member of the tyrosine protein kinase family and is upregulated on proliferating endothelial cells of the tumor vasculature. After single orogastric vaccination, we detected significant numbers of KDR2-tetramer-positive CD8 T cells in the spleens of immunized mice. The efficacy of these cytotoxic T cells was evaluated in a prophylactic setting to protect mice from challenges with B16F10 melanoma cells in a flank tumor model, and to reduce dissemination of spontaneous pulmonary melanoma metastases. Vaccinated mice revealed a reduction of angiogenesis by 62% in the solid tumor and consequently a significant decrease of tumor growth as compared to non-immunized mice. Moreover, in the lung metastasis model, immunization with recombinant Salmonella resulted in a reduction of the metastatic melanoma burden by approximately 60%.

  3. Opposing effects of CXCR3 and CCR5 deficiency on CD8+ T cell-mediated inflammation in the central nervous system of virus-infected mice

    DEFF Research Database (Denmark)

    de Lemos, Carina; Christensen, Jeanette Erbo; Nansen, Anneline

    2005-01-01

    T cells play a key role in the control of viral infection in the CNS but may also contribute to immune-mediated cell damage. To study the redundancy of the chemokine receptors CXCR3 and CCR5 in regulating virus-induced CD8+ T cell-mediated inflammation in the brain, CXCR3/CCR5 double-deficient mice......-deficient mice were more susceptible to intracerebral infection than CXCR3-deficient mice. Analysis of effector T cell generation revealed an accelerated antiviral CD8+ T cell response in CXCR3/CCR5 double-deficient mice. Furthermore, while the accumulation of CD8+ T cells in the neural parenchyma...... were generated and infected intracerebrally with noncytolytic lymphocytic choriomeningitis virus. Because these chemokine receptors are mostly expressed by overlapping subsets of activated CD8+ T cells, it was expected that absence of both receptors would synergistically impair effector T cell invasion...

  4. Expression of human immunodeficiency virus coreceptors CXC chemokine receptor 4 and CC chemokine receptor 5 on monocytes is down-regulated during human endotoxemia

    NARCIS (Netherlands)

    Juffermans, Nicole P.; Weijer, Sebastiaan; Verbon, Annelies; Speelman, Peter; van der Poll, Tom

    2002-01-01

    Lipopolysaccharide (LPS) can inhibit human immunodeficiency virus (HIV) infection in monocytes in vitro. To test the hypothesis that an LPS effect on CXC chemokine receptor 4 (CXCR4) and CC chemokine receptor 5 (CCR5), known coreceptors for HIV, contributes to this effect, 8 healthy men were

  5. CCR5 and CXCR4 chemokine receptor expression and β-chemokine production during early T cell repopulation induced by highly active anti-retroviral therapy

    Science.gov (United States)

    Giovannetti, A; Ensoli, F; Mazzetta, F; De Cristofaro, M; Pierdominici, M; Muratori, D S; Fiorelli, V; Aiuti, F

    1999-01-01

    Expression of chemokine receptors and β-chemokine production by peripheral blood mononuclear cells (PBMC) were determined in HIV-1-infected individuals before and after highly active anti-retroviral therapy (HAART) and their relationship to viral load, T cell phenotype and the expression of immunological activation markers was examined. We found that the expression of CCR5 is up-regulated in HIV-1-infected individuals while CXCR4 appears down-regulated on both CD4 and CD8 T cells compared with normal controls. These alterations are associated with the high levels of viral load. In addition, a relationship was observed between the degree of immune activation and chemokine receptor expression on T cells. However, after 3 months of combined anti-retroviral regimen, expression of CXCR4 significantly increased while CCR5 decreased when compared with pretherapy determinations. This was seen in strict association with a dramatic decrease of viral load and an increase of both CD45RA+/CD62L+ (naive) and CD45RA−/CD62L+ or CD45RA+/CD62L− (memory) T cells accompanied by a significant decrease of the expression of immune activation markers such as HLA-DR and CD38. At enrolment, both spontaneous and lectin-induced RANTES, macrophage inflammatory protein-1α (MIP-1α) and MIP-1β production by PBMC were higher in HIV-1-infected individuals compared with normal controls, although differences for MIP-1β were not statistically significant. However, RANTES and MIP-1α production decreased during HAART at levels closer to that determined with normal controls, while MIP-1β production was less consistently modified. These data indicate that the expression of chemokine receptors CCR5 and CXCR4 and the production of β-chemokines are altered in HIV-infected individuals, and suggest that their early modifications during HAART reflect both the peripheral redistribution of naive/memory T cell compartments and the decrease in levels of T cell activation. Such modifications in the

  6. Dual GPCR and GAG mimicry by the M3 chemokine decoy receptor

    Energy Technology Data Exchange (ETDEWEB)

    Alexander-Brett, Jennifer M.; Fremont, Daved H. (WU-MED)

    2008-09-23

    Viruses have evolved a myriad of evasion strategies focused on undermining chemokine-mediated immune surveillance, exemplified by the mouse {gamma}-herpesvirus 68 M3 decoy receptor. Crystal structures of M3 in complex with C chemokine ligand 1/lymphotactin and CC chemokine ligand 2/monocyte chemoattractant protein 1 reveal that invariant chemokine features associated with G protein-coupled receptor binding are primarily recognized by the decoy C-terminal domain, whereas the N-terminal domain (NTD) reconfigures to engage divergent basic residue clusters on the surface of chemokines. Favorable electrostatic forces dramatically enhance the association kinetics of chemokine binding by M3, with a primary role ascribed to acidic NTD regions that effectively mimic glycosaminoglycan interactions. Thus, M3 employs two distinct mechanisms of chemical imitation to potently sequester chemokines, thereby inhibiting chemokine receptor binding events as well as the formation of chemotactic gradients necessary for directed leukocyte trafficking.

  7. Virus-encoded chemokine receptors--putative novel antiviral drug targets

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M

    2005-01-01

    as such a paramount role in the antiviral immune responses. It is therefore not surprising that viruses have found ways to exploit and subvert the chemokine system by means of molecular mimicry. By ancient acts of molecular piracy and by induction and suppression of endogenous genes, viruses have utilized chemokines...... and their receptors to serve a variety of roles in viral life-cycle. This review focuses on the pharmacology of virus-encoded chemokine receptors, yet also the family of virus-encoded chemokines and chemokine-binding proteins will be touched upon. Key properties of the virus-encoded receptors, compared...... to their closest endogenous homologs, are interactions with a wider range of chemokines, which can act as agonists, antagonists and inverse agonists, and the exploitation of many signal transduction pathways. High constitutive activity is another key property of some--but not all--of these receptors. The chemokine...

  8. Decreased number of CD4+ and CD8+ T cells that express the interleukin-7 receptor in blood and tissues of SIV-infected macaques

    International Nuclear Information System (INIS)

    Moniuszko, Marcin; Edghill-Smith, Yvette; Venzon, David; Stevceva, Liljana; Nacsa, Janos; Tryniszewska, Elzbieta; Tsai, Wen-Po; Franchini, Genoveffa

    2006-01-01

    Acute HIV/SIV (human/simian immunodeficiency virus) infection results in severe CD4 + T cell depletion in lymphoid compartments. During the chronic phase of infection, CD4 + T cell numbers rebound in blood but remain low in the gut-associated lymphoid tissue (GALT), even when viral replication is suppressed by antiretroviral therapy (ART). Thus, strategies to repopulate lymphoid compartments may ameliorate the clinical outcome of HIV/SIV infection. Interleukin (IL)-7 is a key cytokine for the maintenance of homeostatic proliferation of T cells. In HIV/SIV infection, IL-7 expression is increased, likely to compensate for T cell loss, suggesting that supraphysiological administration of IL-7 could provide additional benefit. However, the ability of T cells to respond to IL-7 is dependent on the level of expression of the IL-7 receptor (IL-7R) in T cells in various body compartments. In here, we investigated the proportion of IL-7R + T cells in blood, spleen, gut, and genitourinary tract of healthy and SIV-infected macaques with various degrees of CD4 + T cell depletion. We found that the percentage of T cells expressing IL-7R was significantly lower in both CD4 + and CD8 + T cell subsets in SIV-infected macaques than in healthy animals and this decrease directly correlated with the CD4 + T cell number. Importantly, the proportion of CD4 + and CD8 + T cells expressing IL-7R in blood paralleled that found in tissues. IL-7R + T cells within the SIV-specific CD8 + T cells varied and were lowest in most tissues of viremic macaques, likely reflecting continuous antigen stimulation of effector cells

  9. CXC chemokine receptor 2 contributes to host defense in murine urinary tract infection

    NARCIS (Netherlands)

    Olszyna, D. P.; Florquin, S.; Sewnath, M.; Branger, J.; Speelman, P.; van Deventer, S. J.; Strieter, R. M.; van der Poll, T.

    2001-01-01

    CXC chemokines have been implicated in the recruitment of neutrophils to sites of infection. To determine the role of CXC chemokines in the host response to urinary tract infection (UTI), female mice were treated with an antibody against the major CXC chemokine receptor in the mouse, CXCR2, before

  10. Lymphoid follicle cells in chronic obstructive pulmonary disease overexpress the chemokine receptor CXCR3.

    Science.gov (United States)

    Kelsen, Steven G; Aksoy, Mark O; Georgy, Mary; Hershman, Richard; Ji, Rong; Li, Xiuxia; Hurford, Matthew; Solomides, Charalambos; Chatila, Wissam; Kim, Victor

    2009-05-01

    The mechanisms underlying formation of lung lymphoid follicles (LF) in chronic obstructive pulmonary disease (COPD) are unknown. The chemokine receptor CXCR3 regulates immune responses in secondary lymphoid structures elsewhere in the body and is highly expressed by Th1 lymphocytes in the airway in COPD. Because chemokine receptors control inflammatory cell homing to inflamed tissue, we reasoned that CXCR3 may contribute to LF formation in COPD. We assessed the expression of CXCR3 and its ligands (IP-10/CXCL10, Mig/CXCL9, and ITAC/CXCL11) by LF cells in never-smokers, smokers without COPD, and subjects with COPD. CXCR3, IP-10, Mig, and ITAC expression were assessed in lung sections from 46 subjects (never-smokers, smokers without COPD [S], and subjects with COPD in GOLD stages 1-4) by immunohistochemistry. CXCR3-expressing T cells (CD8+ or CD4+) and B cells (CD20+) were topographically distributed at the follicle periphery and center, respectively. The percentage of immunohistochemically identified CXCR3+ cells increased progressively while proceeding from S through GOLD 3-4 (P < 0.01 for GOLD 3-4 vs. S). Moreover, the number of CXCR3+ follicular cells correlated inversely with FEV(1) (r = 0.60). The CXCR3 ligands IP-10 and Mig were expressed by several cell types in and around the follicle, including CD68+ dendritic cells/ macrophages, airway epithelial cells, endothelial cells, and T and B cells. These results suggest that LF form in the COPD lung by recruitment and/or retention of CXCR3-expressing T and B lymphocytes, which are attracted to the region through production of CXCR3 ligands IP-10 and Mig by lung structural and follicular cells.

  11. Chemokine receptor allelic polymorphisms: relationships to HIV resistance and disease progression

    NARCIS (Netherlands)

    Paxton, W. A.; Kang, S.

    1998-01-01

    It is now well established that an array of CC and CXC chemokine receptors, in association with the CD4 molecule, can interact with the HIV-1 gp120 protein to facilitate viral fusion. A 32bp deletion in the CC chemokine receptor CCR5, the major M-tropic viral co-receptor, provides considerable

  12. Chemokine CCL2 and chemokine receptor CCR2 in early active multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Ransohoff, R M; Strieter, R M

    2004-01-01

    The chemokine monocyte chemoattractant protein (MCP)-1/CCL2 and its receptor CCR2 have been strongly implicated in disease pathogenesis in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis (MS), whereas data on the CCL2-CCR2 axis are scarce in MS. We studied...... the expression of CCR2 on leukocytes in blood and cerebrospinal fluid (CSF) from patients with monosymptomatic optic neuritis and MS, and the concentration of CCL2 in the CSF from these patients. Results were compared with the results in non-inflammatory neurological controls and were correlated with other...... parameters (magnetic resonance imaging and CSF data). Our findings suggest a limited role for CCL2/CCR2 in early active MS....

  13. Deep sequencing of the T-cell receptor repertoire in CD8+ T-large granular lymphocyte leukemia identifies signature landscapes.

    Science.gov (United States)

    Clemente, Michael J; Przychodzen, Bartlomiej; Jerez, Andres; Dienes, Brittney E; Afable, Manuel G; Husseinzadeh, Holleh; Rajala, Hanna L M; Wlodarski, Marcin W; Mustjoki, Satu; Maciejewski, Jaroslaw P

    2013-12-12

    New massively parallel sequencing technology enables, through deep sequencing of rearranged T-cell receptor (TCR) Vβ complementarity-determining region 3 (CDR3) regions, a previously inaccessible level of TCR repertoire analysis. The CDR3 repertoire diversity reflects clonal composition, the potential antigenic recognition spectrum, and the quantity of available T-cell responses. In this context, T-large granular lymphocyte (T-LGL) leukemia is a chronic clonal lymphoproliferation of cytotoxic T cells often associated with autoimmune diseases and various cytopenias. Using CD8(+) T-LGL leukemia as a model disease, we set out to evaluate and compare the TCR deep-sequencing spectra of both patients and healthy controls to better understand how TCR deep sequencing could be used in the diagnosis and monitoring of not only T-LGL leukemia but also reactive processes such as autoimmune disease and infection. Our data demonstrate, with high resolution, significantly decreased diversity of the T-cell repertoire in CD8(+) T-LGL leukemia and suggest that many T-LGL clonotypes may be private to the disease and may not be present in the general public, even at the basal level.

  14. Protein kinase D2 is a digital amplifier of T cell receptor-stimulated diacylglycerol signaling in naïve CD8⁺ T cells.

    Science.gov (United States)

    Navarro, María N; Feijoo-Carnero, Carmen; Arandilla, Alba Gonzalez; Trost, Matthias; Cantrell, Doreen A

    2014-10-21

    Protein kinase D2 (PKD2) is a serine and threonine kinase that is activated in T cells by diacylglycerol and protein kinase C in response to stimulation of the T cell receptor (TCR) by antigen. We quantified the activation of PKD2 at the single-cell level and found that this kinase acts as a sensitive digital amplifier of TCR engagement, enabling CD8(+) T cells to match the production of inflammatory cytokines to the quality and quantity of TCR ligands. There was a digital response pattern of PKD2 activation in response to TCR engagement, such that increasing the concentration and potency of TCR ligands increased the number of cells that exhibited activated PKD2. However, for each cell that responded to TCR stimulation, the entire cellular pool of PKD2 (~400,000 molecules) was activated. Moreover, PKD2 acted as an amplification checkpoint for antigen-stimulated digital cytokine responses and translated the differential strength of TCR signaling to determine the number of naïve CD8(+) T cells that became effector cells. Together, these results provide insights into PKD family kinases and how they act digitally to amplify signaling networks controlled by the TCR.

  15. Structure of CC Chemokine Receptor 5 with a Potent Chemokine Antagonist Reveals Mechanisms of Chemokine Recognition and Molecular Mimicry by HIV

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Han, Gye Won; Abagyan, Ruben; Wu, Beili; Stevens, Raymond C.; Cherezov, Vadim; Kufareva, Irina; Handel, Tracy M. (USC); (Chinese Aca. Sci.); (UCSD)

    2017-06-01

    CCR5 is the primary chemokine receptor utilized by HIV to infect leukocytes, whereas CCR5 ligands inhibit infection by blocking CCR5 engagement with HIV gp120. To guide the design of improved therapeutics, we solved the structure of CCR5 in complex with chemokine antagonist [5P7]CCL5. Several structural features appeared to contribute to the anti-HIV potency of [5P7]CCL5, including the distinct chemokine orientation relative to the receptor, the near-complete occupancy of the receptor binding pocket, the dense network of intermolecular hydrogen bonds, and the similarity of binding determinants with the FDA-approved HIV inhibitor Maraviroc. Molecular modeling indicated that HIV gp120 mimicked the chemokine interaction with CCR5, providing an explanation for the ability of CCR5 to recognize diverse ligands and gp120 variants. Our findings reveal that structural plasticity facilitates receptor-chemokine specificity and enables exploitation by HIV, and provide insight into the design of small molecule and protein inhibitors for HIV and other CCR5-mediated diseases.

  16. Structure of CC Chemokine Receptor 5 with a Potent Chemokine Antagonist Reveals Mechanisms of Chemokine Recognition and Molecular Mimicry by HIV.

    Science.gov (United States)

    Zheng, Yi; Han, Gye Won; Abagyan, Ruben; Wu, Beili; Stevens, Raymond C; Cherezov, Vadim; Kufareva, Irina; Handel, Tracy M

    2017-06-20

    CCR5 is the primary chemokine receptor utilized by HIV to infect leukocytes, whereas CCR5 ligands inhibit infection by blocking CCR5 engagement with HIV gp120. To guide the design of improved therapeutics, we solved the structure of CCR5 in complex with chemokine antagonist [5P7]CCL5. Several structural features appeared to contribute to the anti-HIV potency of [5P7]CCL5, including the distinct chemokine orientation relative to the receptor, the near-complete occupancy of the receptor binding pocket, the dense network of intermolecular hydrogen bonds, and the similarity of binding determinants with the FDA-approved HIV inhibitor Maraviroc. Molecular modeling indicated that HIV gp120 mimicked the chemokine interaction with CCR5, providing an explanation for the ability of CCR5 to recognize diverse ligands and gp120 variants. Our findings reveal that structural plasticity facilitates receptor-chemokine specificity and enables exploitation by HIV, and provide insight into the design of small molecule and protein inhibitors for HIV and other CCR5-mediated diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. CCR2+ and CCR5+ CD8+ T cells increase during viral infection and migrate to sites of infection

    DEFF Research Database (Denmark)

    Nansen, A; Marker, O; Bartholdy, C

    2000-01-01

    Chemokines and their receptors play a critical role in the selective recruitment of various leukocyte subsets. In this study, we correlated the expression of multiple chemokine and CC chemokine receptor (CCR) genes during the course of intracerebral (i.c.) infection with lymphocytic choriomeningi......Chemokines and their receptors play a critical role in the selective recruitment of various leukocyte subsets. In this study, we correlated the expression of multiple chemokine and CC chemokine receptor (CCR) genes during the course of intracerebral (i.c.) infection with lymphocytic...... a rapidly lethal, T cell-independent encephalitis, and infection resulted in a dramatic early up-regulation of chemokine gene expression. Similar marked up-regulation of chemokine expression was not seen until late after LCMV infection and required the presence of activated T cells. Cerebral CCR gene...... expression was dominated by CCR1, CCR2 and CCR5. However, despite a stronger initial chemokine signal in VSV-infected mice, only LCMV-induced T cell-dependent inflammation was found to be associated with substantially increased expression of CCR genes. Virus-activated CD8+ T cells were found to express CCR2...

  18. Allosteric and orthosteric sites in CC chemokine receptor (CCR5), a chimeric receptor approach

    DEFF Research Database (Denmark)

    Thiele, Stefanie; Steen, Anne; Jensen, Pia C

    2011-01-01

    molecules often act more deeply in an allosteric mode. However, opposed to the well described molecular interaction of allosteric modulators in class C 7-transmembrane helix (7TM) receptors, the interaction in class A, to which the chemokine receptors belong, is more sparsely described. Using the CCR5...... chemokine receptor as a model system, we studied the molecular interaction and conformational interchange required for proper action of various orthosteric chemokines and allosteric small molecules, including the well known CCR5 antagonists TAK-779, SCH-C, and aplaviroc, and four novel CCR5 ago......-allosteric molecules. A chimera was successfully constructed between CCR5 and the closely related CCR2 by transferring all extracellular regions of CCR2 to CCR5, i.e. a Trojan horse that resembles CCR2 extracellularly but signals through a CCR5 transmembrane unit. The chimera bound CCR2 (CCL2 and CCL7), but not CCR5...

  19. Chemokine Levels and Chemokine Receptor Expression in the Blood and the Cerebrospinal Fluid of HIV-Infected Patients With Cryptococcal Meningitis and Cryptococcosis-Associated Immune Reconstitution Inflammatory Syndrome

    Science.gov (United States)

    Chang, Christina C.; Omarjee, Saleha; Lim, Andrew; Spelman, Tim; Gosnell, Bernadett I.; Carr, William H.; Elliott, Julian H.; Moosa, Mohamed-Yunus S.; Ndung'u, Thumbi; French, Martyn A.; Lewin, Sharon R.

    2013-01-01

    Background. Human immunodeficiency virus–infected patients with treated cryptococcal meningitis who start combination antiretroviral therapy (cART) are at risk of further neurological deterioration, in part caused by paradoxical cryptococcosis-associated immune reconstitution inflammatory syndrome (C-IRIS). We hypothesized that C-IRIS is associated with alterations of chemokine receptor expression on T cells and chemokine concentrations in cerebrospinal fluid (CSF) that enhance recruitment of T-helper 1 cells and/or myeloid cells to the central nervous system. Methods. In a prospective study of 128 human immunodeficiency virus–infected patients with cryptococcal meningitis who received antifungal therapy followed by cART, we examined the proportions of CD4+ and CD8+ T cells expressing CCR5 and/or CXCR3, in CSF and whole blood and the concentrations of CXCL10, CCL2, and CCL3 in stored CSF and plasma. Results. The proportion of CD4+ and CD8+ T cells expressing CXCR3+CCR5+ and the concentrations of CXCL10, CCL2 and CCL3 were increased in CSF compared with blood at cART initiation (P < .0001). Patients with C-IRIS (n = 26), compared with those with no neurological deterioration (n = 63), had higher CSF ratios of CCL2/CXCL10 and CCL3/CXCL10 and higher proportions of CXCR3+CCR5+CD8+T cells in CSF compared with blood at cART initiation (P = .03, .0053, and .02, respectively). Conclusion. CD8+ T-cell and myeloid cell trafficking to the central nervous system may predispose patients to C-IRIS. PMID:23908492

  20. Evolutionary analysis of functional divergence among chemokine receptors, decoy receptors and viral receptors

    Directory of Open Access Journals (Sweden)

    Hiromi eDaiyasu

    2012-07-01

    Full Text Available Chemokine receptors (CKRs function in the inflammatory response and in vertebrate homeostasis. Decoy and viral receptors are two types of CKR homologues with modified functions from those of the typical CKRs. The decoy receptors are able to bind ligands without signaling. On the other hand, the viral receptors show constitutive signaling without ligands. We examined the sites related to the functional difference. At first, the decoy and viral receptors were each classified into five groups, based on the molecular phylogenetic analysis. A multiple amino acid sequence alignment between each group and the CKRs was then constructed. The difference in the amino acid composition between the group and the CKRs was evaluated as the Kullback-Leibler (KL information value at each alignment site. The KL information value is considered to reflect the difference in the functional constraints at the site. The sites with the top 5% of KL information values were selected and mapped on the structure of a CKR. The comparisons with decoy receptor groups revealed that the detected sites were biased on the intracellular side. In contrast, the sites detected from the comparisons with viral receptor groups were found on both the extracellular and intracellular sides. More sites were found in the ligand-binding pocket in the analyses of the viral receptor groups, as compared to the decoy receptor groups. Some of the detected sites were located in the GPCR motifs. For example, the DRY motif of the decoy receptors was often degraded, although the motif of the viral receptors was basically conserved. The observations for the viral receptor groups suggested that the constraints in the pocket region are loose and that the sites on the intracellular side are different from those for the decoy receptors, which may be related to the constitutive signaling activity of the viral receptors.

  1. Sifting through CD8+T Cell Memory.

    Science.gov (United States)

    Martin, Matthew D; Badovinac, Vladimir P

    2016-12-20

    In this issue of Immunity, Gerlach et al. (2016) describe three distinct memory CD8 + T cell subsets based upon expression of the fractalkine receptor CX3CR1. Their findings revise the paradigm of effector and central memory T cells by revealing a subset of CD8 + memory T cells defined by intermediate levels of expression of CX3CR1 that conducts tissue surveillance. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Tumorigenesis induced by the HHV8-encoded chemokine receptor requires ligand modulation of high constitutive activity

    DEFF Research Database (Denmark)

    Holst, P J; Rosenkilde, M M; Manfra, D

    2001-01-01

    ORF74 (or KSHV-vGPCR) is a highly constitutively active G protein-coupled receptor encoded by HHV8 that is regulated both positively and negatively by endogenous chemokines. When expressed in transgenic mice, this chemokine receptor induces an angioproliferative disease closely resembling Kaposi...

  3. Orphan chemokine receptors in neuroimmunology : functional and pharmacological analysis of L-CCR and HCR

    NARCIS (Netherlands)

    Zuurman, Michael Wilhelmer

    2003-01-01

    In this thesis we have investigated the expression and biological activity of the orphan chemokine receptors L-CCR/HCR in astrocytes and microglia. Several lines of evidence indicate that the chemokines CCL2, CCL5, CCL7 and CCL8 are agonists for these receptors. Although a variety of biological

  4. Differentially Expressed Potassium Channels Are Associated with Function of Human Effector Memory CD8+T Cells.

    Science.gov (United States)

    Sim, Ji Hyun; Kim, Kyung Soo; Park, Hyoungjun; Kim, Kyung-Jin; Lin, Haiyue; Kim, Tae-Joo; Shin, Hyun Mu; Kim, Gwanghun; Lee, Dong-Sup; Park, Chan-Wook; Lee, Dong Hun; Kang, Insoo; Kim, Sung Joon; Cho, Chung-Hyun; Doh, Junsang; Kim, Hang-Rae

    2017-01-01

    The voltage-gated potassium channel, Kv1.3, and the Ca 2+ -activated potassium channel, KCa3.1, regulate membrane potentials in T cells, thereby controlling T cell activation and cytokine production. However, little is known about the expression and function of potassium channels in human effector memory (EM) CD8 + T cells that can be further divided into functionally distinct subsets based on the expression of the interleukin (IL)-7 receptor alpha (IL-7Rα) chain. Herein, we investigated the functional expression and roles of Kv1.3 and KCa3.1 in EM CD8 + T cells that express high or low levels of the IL-7 receptor alpha chain (IL-7Rα high and IL-7Rα low , respectively). In contrast to the significant activity of Kv1.3 and KCa3.1 in IL-7Rα high EM CD8 + T cells, IL-7Rα low EM CD8 + T cells showed lower expression of Kv1.3 and insignificant expression of KCa3.1. Kv1.3 was involved in the modulation of cell proliferation and IL-2 production, whereas KCa3.1 affected the motility of EM CD8 + T cells. The lower motility of IL-7Rα low EM CD8 + T cells was demonstrated using transendothelial migration and motility assays with intercellular adhesion molecule 1- and/or chemokine stromal cell-derived factor-1α-coated surfaces. Consistent with the lower migration property, IL-7Rα low EM CD8 + T cells were found less frequently in human skin. Stimulating IL-7Rα low EM CD8 + T cells with IL-2 or IL-15 increased their motility and recovery of KCa3.1 activity. Our findings demonstrate that Kv1.3 and KCa3.1 are differentially involved in the functions of EM CD8 + T cells. The weak expression of potassium channels in IL-7Rα low EM CD8 + T cells can be revived by stimulation with IL-2 or IL-15, which restores the associated functions. This study suggests that IL-7Rα high EM CD8 + T cells with functional potassium channels may serve as a reservoir for effector CD8 + T cells during peripheral inflammation.

  5. Duffy antigen receptor for chemokines mediates chemokine endocytosis through a macropinocytosis-like process in endothelial cells.

    Directory of Open Access Journals (Sweden)

    Yani Zhao

    Full Text Available The Duffy antigen receptor for chemokines (DARC shows high affinity binding to multiple inflammatory CC and CXC chemokines and is expressed by erythrocytes and endothelial cells. Recent evidence suggests that endothelial DARC facilitates chemokine transcytosis to promote neutrophil recruitment. However, the mechanism of chemokine endocytosis by DARC remains unclear.We investigated the role of several endocytic pathways in DARC-mediated ligand internalization. Here we report that, although DARC co-localizes with caveolin-1 in endothelial cells, caveolin-1 is dispensable for DARC-mediated (125I-CXCL1 endocytosis as knockdown of caveolin-1 failed to inhibit ligand internalization. (125I-CXCL1 endocytosis by DARC was also independent of clathrin and flotillin-1 but required cholesterol and was, in part, inhibited by silencing Dynamin II expression.(125I-CXCL1 endocytosis was inhibited by amiloride, cytochalasin D, and the PKC inhibitor Gö6976 whereas Platelet Derived Growth Factor (PDGF enhanced ligand internalization through DARC. The majority of DARC-ligand interactions occurred on the endothelial surface, with DARC identified along plasma membrane extensions with the appearance of ruffles, supporting the concept that DARC provides a high affinity scaffolding function for surface retention of chemokines on endothelial cells.These results show DARC-mediated chemokine endocytosis occurs through a macropinocytosis-like process in endothelial cells and caveolin-1 is dispensable for CXCL1 internalization.

  6. Role of Conserved Disulfide Bridges and Aromatic Residues in Extracellular Loop 2 of Chemokine Receptor CCR8 for Chemokine and Small Molecule Binding

    DEFF Research Database (Denmark)

    Barington, Line; Rummel, Pia C; Lückmann, Michael

    2016-01-01

    and aromatic residues in extracellular loop 2 (ECL2) for ligand binding and activation in the chemokine receptor CCR8. We used IP3 accumulation and radioligand binding experiments to determine the impact of receptor mutagenesis on both chemokine and small molecule agonist and antagonist binding and action...... in CCR8. We find that the 7 transmembrane (7TM) receptor conserved disulfide bridge (7TM bridge) linking transmembrane helix (TM)III and ECL2 is crucial for chemokine and small molecule action, whereas the chemokine receptor conserved disulfide bridge between the N terminus and TMVII is needed only...

  7. Identification of prostate-specific G-protein coupled receptor as a tumor antigen recognized by CD8(+ T cells for cancer immunotherapy.

    Directory of Open Access Journals (Sweden)

    Satoko Matsueda

    Full Text Available Prostate cancer is the most common cancer among elderly men in the US, and immunotherapy has been shown to be a promising strategy to treat patients with metastatic castration-resistant prostate cancer. Efforts to identify novel prostate specific tumor antigens will facilitate the development of effective cancer vaccines against prostate cancer. Prostate-specific G-protein coupled receptor (PSGR is a novel antigen that has been shown to be specifically over-expressed in human prostate cancer tissues. In this study, we describe the identification of PSGR-derived peptide epitopes recognized by CD8(+ T cells in an HLA-A2 dependent manner.Twenty-one PSGR-derived peptides were predicted by an immuno-informatics approach based on the HLA-A2 binding motif. These peptides were examined for their ability to induce peptide-specific T cell responses in peripheral blood mononuclear cells (PBMCs obtained from either HLA-A2(+ healthy donors or HLA-A2(+ prostate cancer patients. The recognition of HLA-A2 positive and PSGR expressing LNCaP cells was also tested. Among the 21 PSGR-derived peptides, three peptides, PSGR3, PSGR4 and PSGR14 frequently induced peptide-specific T cell responses in PBMCs from both healthy donors and prostate cancer patients. Importantly, these peptide-specific T cells recognized and killed LNCaP prostate cancer cells in an HLA class I-restricted manner.We have identified three novel HLA-A2-restricted PSGR-derived peptides recognized by CD8(+ T cells, which, in turn, recognize HLA-A2(+ and PSGR(+ tumor cells. The PSGR-derived peptides identified may be used as diagnostic markers as well as immune targets for development of anticancer vaccines.

  8. Immunotherapy of non-Hodgkin lymphoma with a defined ratio of CD8+ and CD4+ CD19-specific chimeric antigen receptor-modified T cells

    Science.gov (United States)

    Turtle, Cameron J.; Hanafi, Laïla-Aïcha; Berger, Carolina; Hudecek, Michael; Pender, Barbara; Robinson, Emily; Hawkins, Reed; Chaney, Colette; Cherian, Sindhu; Chen, Xueyan; Soma, Lorinda; Wood, Brent; Li, Daniel; Heimfeld, Shelly; Riddell, Stanley R.; Maloney, David G.

    2016-01-01

    CD19-specific chimeric antigen receptor (CAR)-modified T cells have antitumor activity in B cell malignancies, but factors that impact toxicity and efficacy have been difficult to define because of differences in lymphodepletion regimens and heterogeneity of CAR-T cells administered to individual patients. We conducted a clinical trial in which CD19 CAR-T cells were manufactured from defined T cell subsets and administered in a 1:1 CD4+:CD8+ ratio of CAR-T cells to 32 adults with relapsed and/or refractory B cell non-Hodgkin lymphoma after cyclophosphamide (Cy)-based lymphodepletion chemotherapy with or without fludarabine (Flu). Patients who received Cy/Flu lymphodepletion had markedly increased CAR-T cell expansion and persistence, and higher response rates (50% CR, 72% ORR, n=20) than patients who received Cy-based lymphodepletion without Flu (8% CR, 50% ORR, n=12). The complete response (CR) rate in patients treated with Cy/Flu at the maximally tolerated dose was 64% (82% ORR, n=11). Cy/Flu minimized the effects of an immune response to the murine scFv component of the CAR, which limited CAR-T cell expansion, persistence, and clinical efficacy in patients who received Cy-based lymphodepletion without Flu. Severe cytokine release syndrome (sCRS) and grade ≥ 3 neurotoxicity were observed in 13% and 28% of all patients, respectively. Serum biomarkers one day after CAR-T cell infusion correlated with subsequent development of sCRS and neurotoxicity. Immunotherapy with CD19 CAR-T cells in a defined CD4+:CD8+ ratio allowed identification of correlative factors for CAR-T cell expansion, persistence, and toxicity, and facilitated optimization of a lymphodepletion regimen that improved disease response and overall and progression-free survival. PMID:27605551

  9. Expression of specific chemokines and chemokine receptors in the central nervous system of multiple sclerosis patients

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Tani, M; Jensen, J

    1999-01-01

    Chemokines direct tissue invasion by specific leukocyte populations. Thus, chemokines may play a role in multiple sclerosis (MS), an idiopathic disorder in which the central nervous system (CNS) inflammatory reaction is largely restricted to mononuclear phagocytes and T cells. We asked whether...

  10. Human G Protein–Coupled Receptor Gpr-9-6/Cc Chemokine Receptor 9 Is Selectively Expressed on Intestinal Homing T Lymphocytes, Mucosal Lymphocytes, and Thymocytes and Is Required for Thymus-Expressed Chemokine–Mediated Chemotaxis

    Science.gov (United States)

    Zabel, Brian A.; Agace, William W.; Campbell, James J.; Heath, Heidi M.; Parent, David; Roberts, Arthur I.; Ebert, Ellen C.; Kassam, Nasim; Qin, Shixin; Zovko, Maria; LaRosa, Gregory J.; Yang, Li-Li; Soler, Dulce; Butcher, Eugene C.; Ponath, Paul D.; Parker, Christina M.; Andrew, David P.

    1999-01-01

    TECK (thymus-expressed chemokine), a recently described CC chemokine expressed in thymus and small intestine, was found to mediate chemotaxis of human G protein–coupled receptor GPR-9-6/L1.2 transfectants. This activity was blocked by anti–GPR-9-6 monoclonal antibody (mAb) 3C3. GPR-9-6 is expressed on a subset of memory α4β7high intestinal trafficking CD4 and CD8 lymphocytes. In addition, all intestinal lamina propria and intraepithelial lymphocytes express GPR-9-6. In contrast, GPR-9-6 is not displayed on cutaneous lymphocyte antigen–positive (CLA+) memory CD4 and CD8 lymphocytes, which traffic to skin inflammatory sites, or on other systemic α4β7−CLA− memory CD4/CD8 lymphocytes. The majority of thymocytes also express GPR-9-6, but natural killer cells, monocytes, eosinophils, basophils, and neutrophils are GPR-9-6 negative. Transcripts of GPR-9-6 and TECK are present in both small intestine and thymus. Importantly, the expression profile of GPR-9-6 correlates with migration to TECK of blood T lymphocytes and thymocytes. As migration of these cells is blocked by anti–GPR-9-6 mAb 3C3, we conclude that GPR-9-6 is the principal chemokine receptor for TECK. In agreement with the nomenclature rules for chemokine receptors, we propose the designation CCR-9 for GPR-9-6. The selective expression of TECK and GPR-9-6 in thymus and small intestine implies a dual role for GPR-9-6/CCR-9, both in T cell development and the mucosal immune response. PMID:10544196

  11. Chemokine receptor CCR5 in interferon-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Kristiansen, Thomas Birk; Wittenhagen, P

    2007-01-01

    OBJECTIVE: To study the relationship between CC chemokine receptor CCR5 expression and disease activity in multiple sclerosis (MS) patients treated with beta-interferon (IFN-beta). METHODS: The CCR5 Delta32 allele and a CCR5 promoter polymorphism associated with cell surface expression of CCR5 were...... analyzed in 109 patients with relapsing-remitting MS treated with IFN-beta who were followed clinically for 1 year. Cellular CCR5 expression was measured by flow cytometry. RESULTS: Patients with MS had a higher percentage of CCR5-positive monocytes than healthy controls. Increased monocyte expression...... of CCR5 correlated weakly with an increased short-term relapse risk but there was no relationship between CCR5 Delta32 allele and CCR5 promoter polymorphism genotypes and relapse risk. CONCLUSIONS: The results do not support a major role of CCR5 in the pathogenesis of relapses in MS patients treated...

  12. The chemokine receptor CCR5 in the central nervous system.

    Science.gov (United States)

    Sorce, Silvia; Myburgh, Renier; Krause, Karl-Heinz

    2011-02-01

    The expression and the role of the chemokine receptor CCR5 have been mainly studied in the context of HIV infection. However, this protein is also expressed in the brain, where it can be crucial in determining the outcome in response to different insults. CCR5 expression can be deleterious or protective in controlling the progression of certain infections in the CNS, but it is also emerging that it could play a role in non-infectious diseases. In particular, it appears that, in addition to modulating immune responses, CCR5 can influence neuronal survival. Here, we summarize the present knowledge about the expression of CCR5 in the brain and highlight recent findings suggesting its possible involvement in neuroprotective mechanisms. Copyright © 2011. Published by Elsevier Ltd.

  13. CD8+ T cells in cutaneous T-cell lymphoma: expression of cytotoxic proteins, Fas Ligand, and killing inhibitory receptors and their relationship with clinical behavior

    NARCIS (Netherlands)

    Vermeer, M. H.; van Doorn, R.; Dukers, D.; Bekkenk, M. W.; Meijer, C. J.; Willemze, R.

    2001-01-01

    We investigated the number, phenotype, and prognostic significance of CD8+ T cells in patients with mycosis fungoides (MF) and CD30- primary cutaneous large T-cell lymphoma (PCLTCL). Immunohistochemical stainings for CD8, granzyme B (GrB), T cell-restricted intracellular antigen (TIA-1), Fas ligand

  14. Crystallization and preliminary X-ray structural studies of a high-affinity CD8αα co-receptor to pMHC

    International Nuclear Information System (INIS)

    A high-affinity mutant CD8 (haCD8) has been developed with the aim of developing a therapeutic immunosuppressor. In order to fully understand the nature of the haCD8 interaction, this protein was crystallized using the sitting-drop vapour-diffusion method. The class I CD8 positive T-cell response is involved in a number of conditions in which artificial down-regulation and control would be therapeutically beneficial. Such conditions include a number of autoimmune diseases and graft rejection in transplant patients. Although the CD8 T-cell response is dominated by the TCR–pMHC interaction, activation of T cells is in most cases also dependent on a number of associated signalling molecules. Previous work has demonstrated the ability of one such molecule (CD8) to act as an antagonist to T-cell activation if added in soluble form. Therefore, a high-affinity mutant CD8 (haCD8) has been developed with the aim of developing a therapeutic immunosuppressor. In order to fully understand the nature of the haCD8 interaction, this protein was crystallized using the sitting-drop vapour-diffusion method. Single haCD8 crystals were cryocooled and used for data collection. These crystals belonged to space group P6 4 22 (assumed by similarity to the wild type), with unit-cell parameters a = 101.08, c = 56.54 Å. V M calculations indicated one molecule per asymmetric unit. A 2 Å data set was collected and the structure is currently being determined using molecular replacement

  15. CXCL10/CXCR3-Dependent Mobilization of Herpes Simplex Virus-Specific CD8+ TEM and CD8+ TRM Cells within Infected Tissues Allows Efficient Protection against Recurrent Herpesvirus Infection and Disease.

    Science.gov (United States)

    Srivastava, Ruchi; Khan, Arif A; Chilukuri, Sravya; Syed, Sabrina A; Tran, Tien T; Furness, Julie; Bahraoui, Elmostafa; BenMohamed, Lbachir

    2017-07-15

    Herpes simplex virus 1 (HSV-1) establishes latency within the sensory neurons of the trigeminal ganglia (TG). HSV-specific memory CD8 + T cells play a critical role in preventing HSV-1 reactivation from TG and subsequent virus shedding in tears that trigger recurrent corneal herpetic disease. The CXC chemokine ligand 10 (CXCL10)/CXC chemokine receptor 3 (CXCR3) chemokine pathway promotes T cell immunity to many viral pathogens, but its importance in CD8 + T cell immunity to recurrent herpes has been poorly elucidated. In this study, we determined how the CXCL10/CXCR3 pathway affects TG- and cornea-resident CD8 + T cell responses to recurrent ocular herpesvirus infection and disease using a well-established murine model in which HSV-1 reactivation was induced from latently infected TG by UV-B light. Following UV-B-induced HSV-1 reactivation, a significant increase in both the number and function of HSV-specific CXCR3 + CD8 + T cells was detected in TG and corneas of protected C57BL/6 (B6) mice, but not in TG and corneas of nonprotected CXCL10 -/- or CXCR3 -/- deficient mice. This increase was associated with a significant reduction in both virus shedding and recurrent corneal herpetic disease. Furthermore, delivery of exogenous CXCL10 chemokine in TG of CXCL10 -/- mice, using the neurotropic adeno-associated virus type 8 (AAV8) vector, boosted the number and function of effector memory CD8 + T cells (T EM ) and tissue-resident memory CD8 + T cells (T RM ), but not of central memory CD8 + T cells (T CM ), locally within TG, and improved protection against recurrent herpesvirus infection and disease in CXCL10 -/- deficient mice. These findings demonstrate that the CXCL10/CXCR3 chemokine pathway is critical in shaping CD8 + T cell immunity, locally within latently infected tissues, which protects against recurrent herpesvirus infection and disease. IMPORTANCE We determined how the CXCL10/CXCR3 pathway affects CD8 + T cell responses to recurrent ocular herpesvirus

  16. Antibody-targeted NY-ESO-1 to mannose receptor or DEC-205 in vitro elicits dual human CD8+ and CD4+ T cell responses with broad antigen specificity.

    Science.gov (United States)

    Tsuji, Takemasa; Matsuzaki, Junko; Kelly, Marcus P; Ramakrishna, Venky; Vitale, Laura; He, Li-Zhen; Keler, Tibor; Odunsi, Kunle; Old, Lloyd J; Ritter, Gerd; Gnjatic, Sacha

    2011-01-15

    Immunization of cancer patients with vaccines containing full-length tumor Ags aims to elicit specific Abs and both CD4(+) and CD8(+) T cells. Vaccination with protein Ags, however, often elicits only CD4(+) T cell responses without inducing Ag-specific CD8(+) T cells, as exogenous protein is primarily presented to CD4(+) T cells. Recent data revealed that Ab-mediated targeting of protein Ags to cell surface receptors on dendritic cells could enhance the induction of both CD4(+) and CD8(+) T cells. We investigated in this study if these observations were applicable to NY-ESO-1, a cancer-testis Ag widely used in clinical cancer vaccine trials. We generated two novel targeting proteins consisting of the full-length NY-ESO-1 fused to the C terminus of two human mAbs against the human mannose receptor and DEC-205, both internalizing molecules expressed on APC. These targeting proteins were evaluated for their ability to activate NY-ESO-1-specific human CD4(+) and CD8(+) T cells in vitro. Both targeted NY-ESO-1 proteins rapidly bound to their respective targets on APC. Whereas nontargeted and Ab-targeted NY-ESO-1 proteins similarly activated CD4(+) T cells, cross-presentation to CD8(+) T cells was only efficiently induced by targeted NY-ESO-1. In addition, both mannose receptor and DEC-205 targeting elicited specific CD4(+) and CD8(+) T cells from PBLs of cancer patients. Receptor-specific delivery of NY-ESO-1 to APC appears to be a promising vaccination strategy to efficiently generate integrated and broad Ag-specific immune responses against NY-ESO-1 in cancer patients.

  17. Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Min Sook [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Woo, Min-Yeong [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Department of Biomedical Sciences, The Graduate School, Ajou University (Korea, Republic of); Kwon, Daeho [Department of Microbiology, Kwandong University College of Medicine, Gangneung, Gangwon-do 210-701 (Korea, Republic of); Hong, Allen E. [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Song, Kye Yong [Department of Pathology, Chung-Ang University College of Medicine, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Park, Sun [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Lim, In Kyoung [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of)

    2014-10-01

    In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with the WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.

  18. Targeting the chemokine receptor CXCR3 and its ligand CXCL10 in the central nervous system

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke

    2004-01-01

    focuses on the present data regarding CXCL10 (previously known as IP-10) and CXRC3 in multiple sclerosis, since consistent data has suggested that this chemokine/chemokine receptor pair has a pivotal role in leukocyte recruitment into the central nervous system (CNS) in multiple sclerosis....

  19. Opposing effects of CXCR3 and CCR5 deficiency on CD8+ T cell-mediated inflammation in the central nervous system of virus-infected mice

    DEFF Research Database (Denmark)

    de Lemos, Carina; Christensen, Jeanette Erbo; Nansen, Anneline

    2005-01-01

    T cells play a key role in the control of viral infection in the CNS but may also contribute to immune-mediated cell damage. To study the redundancy of the chemokine receptors CXCR3 and CCR5 in regulating virus-induced CD8+ T cell-mediated inflammation in the brain, CXCR3/CCR5 double-deficient mice...... and therefore protect mice against the otherwise fatal CD8+ T cell-mediated immune attack. Contrary to expectations, the accumulation of mononuclear cells in cerebrospinal fluid was only slightly delayed compared with mice with normal expression of both receptors. Even more surprising, CXCR3/CCR5 double......-deficient mice were more susceptible to intracerebral infection than CXCR3-deficient mice. Analysis of effector T cell generation revealed an accelerated antiviral CD8+ T cell response in CXCR3/CCR5 double-deficient mice. Furthermore, while the accumulation of CD8+ T cells in the neural parenchyma...

  20. Structural basis for chemokine recognition and activation of a viral G protein-coupled receptor

    Energy Technology Data Exchange (ETDEWEB)

    Burg, John S.; Ingram, Jessica R.; Venkatakrishnan, A.J.; Jude, Kevin M.; Dukkipati, Abhiram; Feinberg, Evan N.; Angelini, Alessandro; Waghray, Deepa; Dror, Ron O.; Ploegh, Hidde L.; Garcia, K. Christopher (Stanford); (Stanford-MED); (Whitehead); (MIT)

    2015-03-05

    Chemokines are small proteins that function as immune modulators through activation of chemokine G protein-coupled receptors (GPCRs). Several viruses also encode chemokines and chemokine receptors to subvert the host immune response. How protein ligands activate GPCRs remains unknown. We report the crystal structure at 2.9 angstrom resolution of the human cytomegalovirus GPCR US28 in complex with the chemokine domain of human CX3CL1 (fractalkine). The globular body of CX3CL1 is perched on top of the US28 extracellular vestibule, whereas its amino terminus projects into the central core of US28. The transmembrane helices of US28 adopt an active-state-like conformation. Atomic-level simulations suggest that the agonist-independent activity of US28 may be due to an amino acid network evolved in the viral GPCR to destabilize the receptor’s inactive state.

  1. T Cell Receptor Vβ Staining Identifies the Malignant Clone in Adult T cell Leukemia and Reveals Killing of Leukemia Cells by Autologous CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Aileen G Rowan

    2016-11-01

    Full Text Available There is growing evidence that CD8+ cytotoxic T lymphocyte (CTL responses can contribute to long-term remission of many malignancies. The etiological agent of adult T-cell leukemia/lymphoma (ATL, human T lymphotropic virus type-1 (HTLV-1, contains highly immunogenic CTL epitopes, but ATL patients typically have low frequencies of cytokine-producing HTLV-1-specific CD8+ cells in the circulation. It remains unclear whether patients with ATL possess CTLs that can kill the malignant HTLV-1 infected clone. Here we used flow cytometric staining of TCRVβ and cell adhesion molecule-1 (CADM1 to identify monoclonal populations of HTLV-1-infected T cells in the peripheral blood of patients with ATL. Thus, we quantified the rate of CD8+-mediated killing of the putative malignant clone in ex vivo blood samples. We observed that CD8+ cells from ATL patients were unable to lyse autologous ATL clones when tested directly ex vivo. However, short in vitro culture restored the ability of CD8+ cells to kill ex vivo ATL clones in some donors. The capacity of CD8+ cells to lyse HTLV-1 infected cells which expressed the viral sense strand gene products was significantly enhanced after in vitro culture, and donors with an ATL clone that expressed the HTLV-1 Tax gene were most likely to make a detectable lytic CD8+ response to the ATL cells. We conclude that some patients with ATL possess functional tumour-specific CTLs which could be exploited to contribute to control of the disease.

  2. Structure, function and physiological consequences of virally encoded chemokine seven transmembrane receptors

    DEFF Research Database (Denmark)

    Rosenkilde, M M; Smit, M J; Waldhoer, M

    2008-01-01

    A number of human and animal herpes viruses encode G-protein coupled receptors with seven transmembrane (7TM) segments-most of which are clearly related to human chemokine receptors. It appears, that these receptors are used by the virus for immune evasion, cellular transformation, tissue targeting...... pathogenesis is still poorly understood. Here we focus on the current knowledge of structure, function and trafficking patterns of virally encoded chemokine receptors and further address the putative roles of these receptors in virus survival and host -cell and/or -immune system modulation. Finally, we...

  3. Tumorigenesis induced by the HHV8-encoded chemokine receptor requires ligand modulation of high constitutive activity

    DEFF Research Database (Denmark)

    Holst, P J; Rosenkilde, M M; Manfra, D

    2001-01-01

    sarcoma (KS). Here we demonstrate that several lines of mice carrying mutated receptors deficient in either constitutive activity or chemokine regulation fail to develop KS-like disease. In addition, animals expressing a receptor that preserves chemokine binding and constitutive activity but that does...... not respond to agonist stimulation have a much lower incidence of angiogenic lesions and tumors. These results indicate that induction of the KS-like disease in transgenic mice by ORF74 requires not only high constitutive signaling activity but also modulation of this activity by endogenous chemokines....

  4. Unexpected positive control of NFκB and miR-155 by DGKα and ζ ensures effector and memory CD8+ T cell differentiation

    Science.gov (United States)

    Yang, Jialong; Zhang, Ping; Krishna, Sruti; Wang, Jinli; Lin, Xingguang; Huang, Hongxiang; Xie, Danli; Gorentla, Balachandra; Huang, Rick; Gao, Jimin; Li, Qi-Jing; Zhong, Xiao-Ping

    2016-01-01

    Signals from the T-cell receptor (TCR) and γ-chain cytokine receptors play crucial roles in initiating activation and effector/memory differentiation of CD8 T-cells. We report here that simultaneous deletion of both diacylglycerol kinase (DGK) α and ζ (DKO) severely impaired expansion of CD8 effector T cells and formation of memory CD8 T-cells after Listeria monocytogenes infection. Moreover, ablation of both DGKα and ζ in preformed memory CD8 T-cells triggered death and impaired homeostatic proliferation of these cells. DKO CD8 T-cells were impaired in priming due to decreased expression of chemokine receptors and migration to the draining lymph nodes. Moreover, DKO CD8 T-cells were unexpectedly defective in NFκB-mediated miR-155 transcript, leading to excessive SOCS1 expression and impaired γ-chain cytokine signaling. Our data identified a DGK-NFκB-miR-155-SOCS1 axis that bridges TCR and γ-chain cytokine signaling for robust CD8 T-cell primary and memory responses to bacterial infection. PMID:27014906

  5. Structure, function and physiological consequences of virally encoded chemokine seven transmembrane receptors

    NARCIS (Netherlands)

    Rosenkilde, M.M.; Smit, M.J.; Waldhoer, M.

    2008-01-01

    A number of human and animal herpes viruses encode G-protein coupled receptors with seven transmembrane (7TM) segments - most of which are clearly related to human chemokine receptors. It appears, that these receptors are used by the virus for immune evasion, cellular transformation, tissue

  6. Expression of chemokine receptors CCR5 and CXCR4 on CD4+ T cells and plasma chemokine levels during treatment of active tuberculosis in HIV-1-coinfected patients

    NARCIS (Netherlands)

    Wolday, Dawit; Tegbaru, Belete; Kassu, Afework; Messele, Tsehaynesh; Coutinho, Roel; van Baarle, Debbie; Miedema, Frank

    2005-01-01

    The pathogenesis of persistently elevated plasma HIV viremia in patients coinfected with tuberculosis (TB) during anti-TB treatment in Africans remains unknown. We examined the expression of chemokine receptors CCR5 and CXCR4 on CD4+ T cells and plasma chemokine levels of macrophage inflammatory

  7. Internalization of the chemokine receptor CCR4 can be evoked by orthosteric and allosteric receptor antagonists

    OpenAIRE

    Ajram, Laura; Begg, Malcolm; Slack, Robert; Cryan, Jenni; Hall, David; Hodgson, Simon; Ford, Alison; Barnes, Ashley; Swieboda, Dawid; Mousnier, Aurelie; Solari, Roberto

    2014-01-01

    The chemokine receptor CCR4 has at least two natural agonist ligands, MDC (CCL22) and TARC (CCL17) which bind to the same orthosteric site with a similar affinity. Both ligands are known to evoke chemotaxis of CCR4-bearing T cells and also elicit CCR4 receptor internalization. A series of small molecule allosteric antagonists have been described which displace the agonist ligand, and inhibit chemotaxis. The aim of this study was to determine which cellular coupling pathways are involved in in...

  8. Atypical chemokine receptor ACKR2 mediates chemokine scavenging by primary human trophoblasts and can regulate fetal growth, placental structure, and neonatal mortality in mice.

    Science.gov (United States)

    Teoh, Pek Joo; Menzies, Fiona M; Hansell, Chris A H; Clarke, Mairi; Waddell, Carolann; Burton, Graham J; Nelson, Scott M; Nibbs, Robert J B

    2014-11-15

    Inflammatory chemokines produced in the placenta can direct the migration of placental leukocytes using chemokine receptors that decorate the surface of these cells. Fetal trophoblasts can also express receptors for inflammatory chemokines, and they are one of the few cell types that express atypical chemokine receptor 2 (ACKR2), previously known as D6. ACKR2 binds many inflammatory CC chemokines but cannot stimulate cell migration or activate signaling pathways used by conventional chemokine receptors. Existing evidence suggests that ACKR2 is a specialized chemokine scavenger, but its function in primary human trophoblasts has not been explored. In mice, ACKR2 is thought to be dispensable for the reproductive success of unchallenged females that have conceived naturally, but it can suppress inflammation-induced abortion and aid the survival of implanted allogeneic embryos. In this article, we demonstrate that cultured primary human trophoblasts express ACKR2 far more strongly than genes encoding conventional receptors for inflammatory CC chemokines. Moreover, these cells are capable of the rapid internalization and efficient scavenging of extracellular chemokine, and this is mediated by ACKR2. We also report that in unchallenged DBA/1j mice, Ackr2 deficiency increases the incidence of stillbirth and neonatal death, leads to structural defects in the placenta, and can decrease fetal weight. Loss of Ackr2 specifically from fetal cells makes a key contribution to the placental defects. Thus, primary human trophoblasts use ACKR2 to scavenge chemokines, and ACKR2 deficiency can cause abnormal placental structure and reduced neonatal survival. Copyright © 2014 by The American Association of Immunologists, Inc.

  9. Extracellular Disulfide Bridges Serve Different Purposes in Two Homologous Chemokine Receptors, CCR1 and CCR5

    DEFF Research Database (Denmark)

    Rummel, Pia Cwarzko; Thiele, Stefanie; Hansen, Laerke Smidt

    2013-01-01

    interact with residues in the main binding crevice, we show that the 7TM-conserved bridge is essential for all types of ligand-mediated activation, whereas the chemokine-conserved bridge is dispensable for small-molecule activation in CCR1. However, in striking contrast to previous studies in other...... chemokine receptors, high affinity CCL3 chemokine binding was maintained in the absence of either bridge. In CCR5, the closest homolog to CCR1, a completely different dependency was observed as neither chemokine activation nor binding was retained in the absence of either bridge. In contrast, both bridges...... where dispensable for small-molecule activation. This indicates that CCR5 activity is independent of extracellular regions, whereas in CCR1, preserved folding of ECL2 is necessary for activation. These results indicate that conserved structural features in a receptor subgroup, does not necessarily...

  10. submitter Emerging importance of chemokine receptor CXCR3 and its ligands in cardiovascular diseases

    CERN Document Server

    Altara, R; Brandao, R D; Zeidan, A; Booz, G W; Zouein, F A

    2016-01-01

    The CXC chemokines, CXCL4, -9, -10, -11, CXCL4L1, and the CC chemokine CCL21, activate CXC chemokine receptor 3 (CXCR3), a cell-surface G protein-coupled receptor expressed mainly by Th1 cells, cytotoxic T (Tc) cells and NK cells that have a key role in immunity and inflammation. However, CXCR3 is also expressed by vascular smooth muscle and endothelial cells, and appears to be important in controlling physiological vascular function. In the last decade, evidence from pre-clinical and clinical studies has revealed the participation of CXCR3 and its ligands in multiple cardiovascular diseases (CVDs) of different aetiologies including atherosclerosis, hypertension, cardiac hypertrophy and heart failure, as well as in heart transplant rejection and transplant coronary artery disease (CAD). CXCR3 ligands have also proven to be valid biomarkers for the development of heart failure and left ventricular dysfunction, suggesting an underlining pathophysiological relation between levels of these chemokines and the deve...

  11. The chemokine receptor CCR2 maintains plasmacytoid dendritic cell homeostasis

    DEFF Research Database (Denmark)

    Cédile, Oriane; Østerby Jørgensen, Line; Frank, Ida

    2017-01-01

    Thymic dendritic cells (DC) play a role in central tolerance. Three thymic DC subtypes have been described: plasmacytoid DC (pDC) and two conventional DC (cDC), CD8α+ Sirpα- DC and Sirpα+ CD8α- cDC. Both pDC and Sirpα+ cDC can take up antigen in periphery and migrate into the thymus in response t...... by CCL2 or CCR2 deficiency. Although some thymic progenitors expressed CCR2, this did not include those that give rise to pDC. Based on these results, we propose that CCR2 is involved in pDC homeostasis but its ligand CCL2 does not play a major role....

  12. Vaccine molecules targeting Xcr1 on cross-presenting DCs induce protective CD8+ T-cell responses against influenza virus.

    Science.gov (United States)

    Fossum, Even; Grødeland, Gunnveig; Terhorst, Dorothea; Tveita, Anders A; Vikse, Elisabeth; Mjaaland, Siri; Henri, Sandrine; Malissen, Bernard; Bogen, Bjarne

    2015-02-01

    Targeting antigens to cross-presenting dendritic cells (DCs) is a promising method for enhancing CD8(+) T-cell responses. However, expression patterns of surface receptors often vary between species, making it difficult to relate observations in mice to other animals. Recent studies have indicated that the chemokine receptor Xcr1 is selectively expressed on cross-presenting murine CD8α(+) DCs, and that the expression is conserved on homologous DC subsets in humans (CD141(+) DCs), sheep (CD26(+) DCs), and macaques (CADM1(+) DCs). We therefore tested if targeting antigens to Xcr1 on cross-presenting DCs using antigen fused to Xcl1, the only known ligand for Xcr1, could enhance immune responses. Bivalent Xcl1 fused to model antigens specifically bound CD8α(+) DCs and increased proliferation of antigen-specific T cells. DNA vaccines encoding dimeric Xcl1-hemagglutinin (HA) fusion proteins induced cytotoxic CD8(+) T-cell responses, and mediated full protection against a lethal challenge with influenza A virus. In addition to enhanced CD8(+) T-cell responses, targeting of antigen to Xcr1 induced CD4(+) Th1 responses and highly selective production of IgG2a antibodies. In conclusion, targeting of dimeric fusion vaccine molecules to CD8α(+) DCs using Xcl1 represents a novel and promising method for induction of protective CD8(+) T-cell responses. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Mutational analysis of the extracellular disulphide bridges of the atypical chemokine receptor ACKR3/CXCR7 uncovers multiple binding and activation modes for its chemokine and endogenous non-chemokine agonists.

    Science.gov (United States)

    Szpakowska, Martyna; Meyrath, Max; Reynders, Nathan; Counson, Manuel; Hanson, Julien; Steyaert, Jan; Chevigné, Andy

    2018-03-09

    The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike classical chemokine receptors, can respond to chemokines from both the CXC and CC families as well as to the endogenous peptides BAM22 and adrenomedullin. Moreover, despite belonging to the G protein coupled receptor family, its function appears to be mainly dependent on β-arrestin. ACKR3 has also been shown to continuously cycle between the plasma membrane and the endosomal compartments, suggesting a possible role as a scavenging receptor. So far, the molecular basis accounting for these atypical binding and signalling properties remains elusive. Noteworthy, ACKR3 extracellular domains bear three disulphide bridges. Two of them lie on top of the two main binding subpockets and are conserved among chemokine receptors, and one, specific to ACKR3, forms an intra-N terminus four-residue-loop of so far unknown function. Here, by mutational and functional studies, we examined the impact of the different disulphide bridges for ACKR3 folding, ligand binding and activation. We showed that, in contrast to most classical chemokine receptors, none of the extracellular disulphide bridges was essential for ACKR3 function. However, the disruption of the unique ACKR3 N-terminal loop drastically reduced the binding of CC chemokines whereas it only had a mild impact on CXC chemokine binding. Mutagenesis also uncovered that chemokine and endogenous non-chemokine ligands interact and activate ACKR3 according to distinct binding modes characterized by different transmembrane domain subpocket occupancy and N-terminal loop contribution, with BAM22 mimicking the binding mode of CC chemokine N terminus. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. CD8αα expression marks terminally differentiated human CD8+ T cells expanded in chronic viral infection

    Directory of Open Access Journals (Sweden)

    Lucy Jane Walker

    2013-08-01

    Full Text Available The T cell co-receptor CD8αβ enhances T cell sensitivity to antigen, however studies indicate CD8αα has the converse effect and acts as a co-repressor. Using a combination of Thymic Leukaemia antigen (TL tetramer, which directly binds CD8αα, anti-CD161 and anti-Vα7.2 antibodies we have been able for the first time to clearly define CD8αα expression on human CD8 T cells subsets. In healthy controls CD8αα is most highly expressed by CD161 bright (CD161++ mucosal associated invariant T (MAIT cells, with CD8αα expression highly restricted to the TCR Vα7.2+ cells of this subset. We also identified CD8αα-expressing populations within the CD161 mid (CD161+ and negative (CD161- non-MAIT CD8 T cell subsets and show TL-tetramer binding to correlate with expression of CD8β at low levels in the context of maintained CD8α expression (CD8α+CD8βlow. In addition, we found CD161-CD8α+CD8βlow populations to be significantly expanded in the peripheral blood of HIV-1 and hepatitis B (mean of 47% and 40% of CD161- T cells respectively infected individuals. Such CD8αα expressing T cells are an effector-memory population (CD45RA-, CCR7-, CD62L- that express markers of activation and maturation (HLA-DR+, CD28-, CD27-, CD57+ and are functionally distinct, expressing greater levels of TNF-α and IFN-γ on stimulation and perforin at rest than their CD8α+CD8βhigh counterparts. Antigen-specific T cells in HLA-B*4201+HIV-1 infected patients are found within both the CD161-CD8α+CD8βhigh and CD161-CD8α+CD8βlow populations. Overall we have clearly defined CD8αα expressing human T cell subsets using the TL-tetramer, and have demonstrated CD161-CD8α+CD8βlow populations, highly expanded in disease settings, to co-express CD8αβ and CD8αα. Co-expression of CD8αα on CD8αβ T cells may impact on their overall function in-vivo and contribute to the distinctive phenotype of highly differentiated populations in HBV and HIV-1 infection.

  15. Circulating Cxcr5-Expressing Cd8+T-Cells are Major Producers of Il-21 and Associate with Limited Hiv Replication.

    Science.gov (United States)

    Perdomo-Celis, Federico; Taborda, Natalia A; Rugeles, Maria T

    2018-04-10

    Despite advances made with the highly active anti-retroviral therapy (HAART) in the control of the human immunodeficiency virus 1 (HIV) infection, a cure has not been achieved due to the persistence of viral reservoirs. The major HIV reservoirs remain in the lymphoid follicles due to, among other factors, the partial absence of CD8T-cells in these structures. Recently, lymphoid follicle-confined and circulating CD8T-cells expressing the C-X-C chemokine receptor type 5 (CXCR5) were described, possessing antiviral mechanisms which could help to control HIV replication. and methods: By flow cytometry, we characterized the phenotype and function of circulating CXCR5-expressing CD8T-cells in HIV-infected patients with natural or HAART-induced control of HIV replication. Circulating CXCR5-expressing CD8T-cells exhibited low or null expression of the C-C chemokine receptor type 7 (CCR7) and had a transitional memory phenotype. Particular redistributions of CXCR5-expressing CD8T-cells were found in HIV-infected patients, and they were partially restored by HAART. The frequency of CXCR5CCR7CD8T-cells was higher in spontaneous HIV controllers and negatively correlated with plasma HIV RNA levels. Total and HIV-specific CXCR5CD8T-cells were major producers of interleukin-21, and this function was positively associated with their interferon-γ production. Circulating CXCR5-expressing CD8T-cells are associated with low level HIV replication, could be novel correlates of protection and potentially useful in the eradication of HIV reservoirs.

  16. Cd8 enhancer E8I and Runx factors regulate CD8α expression in activated CD8+ T cells

    OpenAIRE

    Hassan, Hammad; Sakaguchi, Shinya; Tenno, Mari; Kopf, Aglaja; Boucheron, Nicole; Carpenter, Andrea C.; Egawa, Takeshi; Taniuchi, Ichiro; Ellmeier, Wilfried

    2011-01-01

    Cd8a and Cd8b1 coreceptor gene (Cd8) expression is tightly controlled during T-cell development by the activity of five Cd8 enhancers (E8I–E8V). Here we demonstrate a unique transcriptional program regulating CD8 expression during CD8+ effector T-cell differentiation. The Cd8 enhancer E8I and Runx/core-binding factor-β (CBFβ) complexes were required for the establishment of this regulatory circuit, because E8I-, Runx3-, or CBFβ-deficient CD8+ T cells down-regulated CD8α expression during acti...

  17. Structure of CC chemokine receptor 2 with orthosteric and allosteric antagonists

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Qin, Ling; Ortiz Zacarías, Natalia V.; de Vries, Henk; Han, Gye Won; Gustavsson, Martin; Dabros, Marta; Zhao, Chunxia; Cherney, Robert J.; Carter, Percy; Stamos, Dean; Abagyan, Ruben; Cherezov, Vadim; Stevens, Raymond C.; IJzerman, Adriaan P.; Heitman, Laura H.; Tebben, Andrew; Kufareva, Irina; Handel , Tracy M. (Vertex Pharm); (Leiden-MC); (USC); (BMS); (UCSD)

    2016-12-07

    CC chemokine receptor 2 (CCR2) is one of 19 members of the chemokine receptor subfamily of human class A G-protein-coupled receptors. CCR2 is expressed on monocytes, immature dendritic cells, and T-cell subpopulations, and mediates their migration towards endogenous CC chemokine ligands such as CCL2 (ref. 1). CCR2 and its ligands are implicated in numerous inflammatory and neurodegenerative diseases2 including atherosclerosis, multiple sclerosis, asthma, neuropathic pain, and diabetic nephropathy, as well as cancer3. These disease associations have motivated numerous preclinical studies and clinical trials4 (see http://www.clinicaltrials.gov) in search of therapies that target the CCR2–chemokine axis. To aid drug discovery efforts5, here we solve a structure of CCR2 in a ternary complex with an orthosteric (BMS-681 (ref. 6)) and allosteric (CCR2-RA-[R]7) antagonist. BMS-681 inhibits chemokine binding by occupying the orthosteric pocket of the receptor in a previously unseen binding mode. CCR2-RA-[R] binds in a novel, highly druggable pocket that is the most intracellular allosteric site observed in class A G-protein-coupled receptors so far; this site spatially overlaps the G-protein-binding site in homologous receptors. CCR2-RA-[R] inhibits CCR2 non-competitively by blocking activation-associated conformational changes and formation of the G-protein-binding interface. The conformational signature of the conserved microswitch residues observed in double-antagonist-bound CCR2 resembles the most inactive G-protein-coupled receptor structures solved so far. Like other protein–protein interactions, receptor–chemokine complexes are considered challenging therapeutic targets for small molecules, and the present structure suggests diverse pocket epitopes that can be exploited to overcome obstacles in drug design.

  18. Impact of genetic variations in C-C chemokine receptors and ligands on infectious diseases.

    Science.gov (United States)

    Qidwai, Tabish; Khan, M Y

    2016-10-01

    Chemokine receptors and ligands are crucial for extensive immune response against infectious diseases such as malaria, leishmaniasis, HIV and tuberculosis and a wide variety of other diseases. Role of chemokines are evidenced in the activation and regulation of immune cell migration which is important for immune response against diseases. Outcome of disease is determined by complex interaction among pathogen, host genetic variability and surrounding milieu. Variation in expression or function of chemokines caused by genetic polymorphisms could be associated with attenuated immune responses. Exploration of chemokine genetic polymorphisms in therapeutic response, gene regulation and disease outcome is important. Infectious agents in human host alter the expression of chemokines via epigenetic alterations and thus contribute to disease pathogenesis. Although some fragmentary data are available on chemokine genetic variations and their contribution in diseases, no unequivocal conclusion has been arrived as yet. We therefore, aim to investigate the association of CCR5-CCL5 and CCR2-CCL2 genetic polymorphisms with different infectious diseases, transcriptional regulation of gene, disease severity and response to therapy. Furthermore, the role of epigenetics in genes related to chemokines and infectious disease are also discussed. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  19. The role of CC chemokine receptor 5 in antiviral immunity

    DEFF Research Database (Denmark)

    Nansen, Anneline; Christensen, Jan Pravsgaard; Andreasen, Susanne Ørding

    2002-01-01

    that the virus-induced clonal expansion of antigen-specific T cells was augmented in CCR5(-/-) mice especially with regard to the CD4(+) subset. Despite absence of CCR5, intracerebral infection invariably resulted in lethal T cell-mediated meningitis, and quantitative and qualitative analysis of the inflammatory...... influence of CCR5 was found, not even when viral peptide was used as local trigger instead of live virus. Finally, long-term CD8(+) T cell-mediated immune surveillance was efficiently sustained in CCR5(-/-) mice. Taken together, these results indicate that expression of CCR5 is not critical for T cell...

  20. Dynamic T-lymphocyte chemokine receptor expression induced by interferon-beta therapy in multiple sclerosis

    DEFF Research Database (Denmark)

    Krakauer, M; Sorensen, P S; Khademi, M

    2006-01-01

    and immunoregulatory genes. In conclusion, IFN-beta treatment caused 'steady-state' increases of several chemokine receptors relevant for CD4(+) T-lymphocyte trafficking and function, possibly facilitating lymphocyte migration into the CNS. An important therapeutic effect of IFN-beta treatment may be the normalization......Treatment with interferon (IFN)-beta reduces clinical disease activity in multiple sclerosis (MS). Using flow cytometry, an enzyme-linked immunosorbent assay and a real-time polymerase chain reaction, we studied in vivo IFN-beta-induced effects on CD4(+) T-lymphocyte chemokine receptor expression...... as these influence central nervous system (CNS) transmigration and inflammation. At 'steady state' (>/=1 day after the most recent IFN-beta injection), IFN-beta treatment increased CD4(+) T-cell surface expression of CC chemokine receptor (CCR)4, CCR5 and CCR7 after 3 months of treatment, whereas that of CXC...

  1. Structure of the CCR5 Chemokine Receptor-HIV Entry Inhibitor Maraviroc Complex

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Qiuxiang; Zhu, Ya; Li, Jian; Chen, Zhuxi; Han, Gye Won; Kufareva, Irina; Li, Tingting; Ma, Limin; Fenalti, Gustavo; Li, Jing; Zhang, Wenru; Xie, Xin; Yang, Huaiyu; Jiang, Hualiang; Cherezov, Vadim; Liu, Hong; Stevens, Raymond C.; Zhao, Qiang; Wu, Beili [Scripps; (Chinese Aca. Sci.); (UCSD)

    2013-10-21

    The CCR5 chemokine receptor acts as a co-receptor for HIV-1 viral entry. Here we report the 2.7 angstrom–resolution crystal structure of human CCR5 bound to the marketed HIV drug maraviroc. The structure reveals a ligand-binding site that is distinct from the proposed major recognition sites for chemokines and the viral glycoprotein gp120, providing insights into the mechanism of allosteric inhibition of chemokine signaling and viral entry. A comparison between CCR5 and CXCR4 crystal structures, along with models of co-receptor–gp120-V3 complexes, suggests that different charge distributions and steric hindrances caused by residue substitutions may be major determinants of HIV-1 co-receptor selectivity. These high-resolution insights into CCR5 can enable structure-based drug discovery for the treatment of HIV-1 infection.

  2. [Altered expression of survival (CD127) and death (Fas) receptors in total, naïve and memory CD8 T lymphocytes from human immunodeficiency virus infected patients: possible implications for progression of infection].

    Science.gov (United States)

    Alfonzo, Miguel; Suárez, José; Díaz, Alexandra; Comegna, Mario; Valenzuela, Patricia; Sánchez, María; Hernández, Dimas; Hung, Alida

    2008-06-01

    We studied the ex vivo and in vitro expression of CD95/Fas and CD127 receptors in total, naive and memory CD8+ T cells from HIV infected patients with different blood counts of CD4+ T cells. In addition, spontaneous and induced apoptosis were determined in vitro using a viral antigen (Env), along with an evaluation of their specific proliferative capacity. The obtained results demonstrated that patients with low counts of CD4+ T cells (CD4 CD4+ T cells in blood (CD4> 250/microL). In vitro analyses using Env antigen showed that CD8+ T cells displayed a similar expression of both receptors, with a higher incidence of spontaneous and induced apoptosis and a diminished proliferative capacity as compared with controls. Results indicate how the progression of VIH infection in non-treated patients is related to a decrease of CD8+ T cells in blood, characterized by failures in their proliferative capacity and apoptosis frequency, which is demonstrated by the altered expression of CD127 and CD95/Fas expression.

  3. Gene Expression Profiling of Chemokines and Their Receptors in Low and High Grade Astrocytoma

    Science.gov (United States)

    Sharma, Ira; Singh, Avninder; Sharma, Karam Chand; Saxena, Sunita

    2017-05-01

    Background: Despite intense interest in molecular characterization and searches for novel therapeutic targets, the glioblastoma remains a formidable clinical challenge. Among many contributors to gliomagenesis, chemokines have drawn special attention due to their involvement in a plethora of biological processes and pathological conditions. In the present study we aimed to elucidate any pro-gliomagenic chemokine axis and probable roles in development of glioblastoma multiforme (GBM). Method: An array of 84 chemokines, chemokine receptors and related genes were studied by real time PCR with comparison between low grade astrocytoma (diffuse astrocytoma – grade II) and high grade astrocytoma (glioblastoma multiforme – grade IV). Gene ontology analysis and database mining were performed to funnel down the important axis in GBM followed by validation at the protein level by immunohistochemistry on tissue microarrays. Results: Gene expression and gene ontology analysis identified CXCL8 as an important chemokine which was more frequently up-regulated in GBM as compared to diffuse astrocytoma. Further we demonstrated localization of CXCL8 and its receptors in glioblastoma possibly affecting autocrine and paracrine signalling that promotes tumor cell proliferation and neovascularisation with vascular mimicry. Conclusion: From these results CXCL8 appears to be an important gliomagenic chemokine which may be involved in GBM growth by promoting tumor cell proliferation and neovascularization via vascular mimicry. Further in vitro and in vivo investigations are required to explore its potential candidature in anti-GBM therapy. Creative Commons Attribution License

  4. Phenotypical and functional characterization of double-negative (CD4-CD8-) alpha beta T-cell receptor positive cells from an immunodeficient patient

    DEFF Research Database (Denmark)

    Illum, N; Ralfkiaer, E; Pallesen, G

    1991-01-01

    We have characterized CD4-CD8- double-negative (DN) alpha beta TCR+ T cells from a patient with immunodeficiency, lymphocytosis, lymphadenopathy, and hepatosplenomegaly. The majority of peripheral blood lymphocytes were DN alpha beta TCR+ T cells as evaluated by FACS and biochemical analysis...... (MoAbs) indicated a polyclonal T-cell expansion. Thymic biopsy showed normal histology, whereas lymph node biopsy samples showed altered histological and immunohistological patterns with markedly expanded paracortical areas containing the DN T cells of the same phenotype as found in peripheral blood T...

  5. Internalization of the chemokine receptor CCR4 can be evoked by orthosteric and allosteric receptor antagonists.

    Science.gov (United States)

    Ajram, Laura; Begg, Malcolm; Slack, Robert; Cryan, Jenni; Hall, David; Hodgson, Simon; Ford, Alison; Barnes, Ashley; Swieboda, Dawid; Mousnier, Aurelie; Solari, Roberto

    2014-04-15

    The chemokine receptor CCR4 has at least two natural agonist ligands, MDC (CCL22) and TARC (CCL17) which bind to the same orthosteric site with a similar affinity. Both ligands are known to evoke chemotaxis of CCR4-bearing T cells and also elicit CCR4 receptor internalization. A series of small molecule allosteric antagonists have been described which displace the agonist ligand, and inhibit chemotaxis. The aim of this study was to determine which cellular coupling pathways are involved in internalization, and if antagonists binding to the CCR4 receptor could themselves evoke receptor internalization. CCL22 binding coupled CCR4 efficiently to β-arrestin and stimulated GTPγS binding however CCL17 did not couple to β-arrestin and only partially stimulated GTPγS binding. CCL22 potently induced internalization of almost all cell surface CCR4, while CCL17 showed only weak effects. We describe four small molecule antagonists that were demonstrated to bind to two distinct allosteric sites on the CCR4 receptor, and while both classes inhibited agonist ligand binding and chemotaxis, one of the allosteric sites also evoked receptor internalization. Furthermore, we also characterize an N-terminally truncated version of CCL22 which acts as a competitive antagonist at the orthosteric site, and surprisingly also evokes receptor internalization without demonstrating any agonist activity. Collectively this study demonstrates that orthosteric and allosteric antagonists of the CCR4 receptor are capable of evoking receptor internalization, providing a novel strategy for drug discovery against this class of target. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Migration and chemokine receptor pattern of colitis-preventing DX5+NKT cells.

    Science.gov (United States)

    Hornung, Matthias; Werner, Jens M; Farkas, Stefan; Schlitt, Hans J; Geissler, Edward K

    2011-11-01

    DX5(+)NKT cells are a subpopulation of NKT cells expressing both T cell receptor and NK cell markers that show an immune-regulating function. Transferred DX5(+)NKT cells from immune competent Balb/c mice can prevent or reduce induced colitis in severe combined immunodeficient (SCID) mice. Here, we investigated the in vivo migration of DX5(+)NKT cells and their corresponding chemokine receptor patterns. DX5(+)NKT cells were isolated from spleens of Balb/c mice and transferred into Balb/c SCID mice. After 2 and 8 days, in vivo migration was examined using in vivo microscopy. In addition, the chemokine receptor pattern was analyzed with fluorescence-activated cell sorting (FACS) and the migration assay was performed. Our results show that labeled DX5(+)NKT cells were primarily detectable in mesenteric lymph nodes and spleen after transfer. After 8 days, DX5(+)NKT cells were observed in the colonic tissues, especially the appendix. FACS analysis of chemokine receptors in DX5(+)NKT cells revealed expression of CCR3, CCR6, CCR9, CXCR3, CXCR4, and CXCR6, but no CCR5, CXCR5, or the lymphoid homing receptor CCR7. Stimulation upregulated especially CCR7 expression, and chemokine receptor patterns were different between splenic and liver DX5(+)NKT cells. These data indicate that colitis-preventing DX5(+)NKT cells need to traffic through lymphoid organs to execute their immunological function at the site of inflammation. Furthermore, DX5(+)NKT cells express a specific chemokine receptor pattern with an upregulation of the lymphoid homing receptor CCR7 after activation.

  7. Bioenergetic Insufficiencies Due to Metabolic Alterations Regulated by the Inhibitory Receptor PD-1 Are an Early Driver of CD8(+) T Cell Exhaustion.

    Science.gov (United States)

    Bengsch, Bertram; Johnson, Andy L; Kurachi, Makoto; Odorizzi, Pamela M; Pauken, Kristen E; Attanasio, John; Stelekati, Erietta; McLane, Laura M; Paley, Michael A; Delgoffe, Greg M; Wherry, E John

    2016-08-16

    Dynamic reprogramming of metabolism is essential for T cell effector function and memory formation. However, the regulation of metabolism in exhausted CD8(+) T (Tex) cells is poorly understood. We found that during the first week of chronic lymphocytic choriomeningitis virus (LCMV) infection, before severe dysfunction develops, virus-specific CD8(+) T cells were already unable to match the bioenergetics of effector T cells generated during acute infection. Suppression of T cell bioenergetics involved restricted glucose uptake and use, despite persisting mechanistic target of rapamycin (mTOR) signaling and upregulation of many anabolic pathways. PD-1 regulated early glycolytic and mitochondrial alterations and repressed transcriptional coactivator PGC-1α. Improving bioenergetics by overexpression of PGC-1α enhanced function in developing Tex cells. Therapeutic reinvigoration by anti-PD-L1 reprogrammed metabolism in a subset of Tex cells. These data highlight a key metabolic control event early in exhaustion and suggest that manipulating glycolytic and mitochondrial metabolism might enhance checkpoint blockade outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. CD8+ T cells with characteristic T cell receptor beta motif are detected in blood and expanded in synovial fluid of ankylosing spondylitis patients.

    Science.gov (United States)

    Komech, Ekaterina A; Pogorelyy, Mikhail V; Egorov, Evgeniy S; Britanova, Olga V; Rebrikov, Denis V; Bochkova, Anna G; Shmidt, Evgeniya I; Shostak, Nadejda A; Shugay, Mikhail; Lukyanov, Sergey; Mamedov, Ilgar Z; Lebedev, Yuriy B; Chudakov, Dmitriy M; Zvyagin, Ivan V

    2018-02-22

    The risk of AS is associated with genomic variants related to antigen presentation and specific cytokine signalling pathways, suggesting the involvement of cellular immunity in disease initiation/progression. The aim of the present study was to explore the repertoire of TCR sequences in healthy donors and AS patients to uncover AS-linked TCR variants. Using quantitative molecular-barcoded 5'-RACE, we performed deep TCR β repertoire profiling of peripheral blood (PB) and SF samples for 25 AS patients and 108 healthy donors. AS-linked TCR variants were identified using a new computational approach that relies on a probabilistic model of the VDJ rearrangement process. Using the donor-agnostic probabilistic model, we reveal a TCR β motif characteristic for PB of AS patients, represented by eight highly homologous amino acid sequence variants. Some of these variants were previously reported in SF and PB of patients with ReA and in PB of AS patients. We demonstrate that identified AS-linked clones have a CD8+ phenotype, present at relatively low frequencies in PB, and are significantly enriched in matched SF samples of AS patients. Our results suggest the involvement of a particular antigen-specific subset of CD8+ T cells in AS pathogenesis, confirming and expanding earlier findings. The high similarity of the clonotypes with the ones found in ReA implies common mechanisms for the initiation of the diseases.

  9. Evidence favoring the involvement of CC chemokine receptor (CCR) 5 in T-lymphocyte accumulation in optic neuritis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Ransohoff, R M; Jensen, J

    2003-01-01

    To define the relationships between levels of chemokine receptor (CCR)5+ T-cells in blood and cerebrospinal fluid (CSF) of optic neuritis (ON) and control patients (CON).......To define the relationships between levels of chemokine receptor (CCR)5+ T-cells in blood and cerebrospinal fluid (CSF) of optic neuritis (ON) and control patients (CON)....

  10. The DRF motif of CXCR6 as chemokine receptor adaptation to adhesion.

    Directory of Open Access Journals (Sweden)

    Andrea Koenen

    Full Text Available The CXC-chemokine receptor 6 (CXCR6 is a class A GTP-binding protein-coupled receptor (GPCRs that mediates adhesion of leukocytes by interacting with the transmembrane cell surface-expressed chemokine ligand 16 (CXCL16, and also regulates leukocyte migration by interacting with the soluble shed variant of CXCL16. In contrast to virtually all other chemokine receptors with chemotactic activity, CXCR6 carries a DRF motif instead of the typical DRY motif as a key element in receptor activation and G protein coupling. In this work, modeling analyses revealed that the phenylalanine F3.51 in CXCR6 might have impact on intramolecular interactions including hydrogen bonds by this possibly changing receptor function. Initial investigations with embryonic kidney HEK293 cells and further studies with monocytic THP-1 cells showed that mutation of DRF into DRY does not influence ligand binding, receptor internalization, receptor recycling, and protein kinase B (AKT signaling. Adhesion was slightly decreased in a time-dependent manner. However, CXCL16-induced calcium signaling and migration were increased. Vice versa, when the DRY motif of the related receptor CX3CR1 was mutated into DRF the migratory response towards CX3CL1 was diminished, indicating that the presence of a DRF motif generally impairs chemotaxis in chemokine receptors. Transmembrane and soluble CXCL16 play divergent roles in homeostasis, inflammation, and cancer, which can be beneficial or detrimental. Therefore, the DRF motif of CXCR6 may display a receptor adaptation allowing adhesion and cell retention by transmembrane CXCL16 but reducing the chemotactic response to soluble CXCL16. This adaptation may avoid permanent or uncontrolled recruitment of inflammatory cells as well as cancer metastasis.

  11. CXCR5-Dependent Entry of CD8 T Cells into Rhesus Macaque B-Cell Follicles Achieved through T-Cell Engineering.

    Science.gov (United States)

    Ayala, Victor I; Deleage, Claire; Trivett, Matthew T; Jain, Sumiti; Coren, Lori V; Breed, Matthew W; Kramer, Joshua A; Thomas, James A; Estes, Jacob D; Lifson, Jeffrey D; Ott, David E

    2017-06-01

    Follicular helper CD4 T cells, T FH , residing in B-cell follicles within secondary lymphoid tissues, are readily infected by AIDS viruses and are a major source of persistent virus despite relative control of viral replication. This persistence is due at least in part to a relative exclusion of effective antiviral CD8 T cells from B-cell follicles. To determine whether CD8 T cells could be engineered to enter B-cell follicles, we genetically modified unselected CD8 T cells to express CXC chemokine receptor 5 (CXCR5), the chemokine receptor implicated in cellular entry into B-cell follicles. Engineered CD8 T cells expressing human CXCR5 (CD8 hCXCR5 ) exhibited ligand-specific signaling and chemotaxis in vitro Six infected rhesus macaques were infused with differentially fluorescent dye-labeled autologous CD8 hCXCR5 and untransduced CD8 T cells and necropsied 48 h later. Flow cytometry of both spleen and lymph node samples revealed higher frequencies of CD8 hCXCR5 than untransduced cells, consistent with preferential trafficking to B-cell follicle-containing tissues. Confocal fluorescence microscopy of thin-sectioned lymphoid tissues demonstrated strong preferential localization of CD8 hCXCR5 T cells within B-cell follicles with only rare cells in extrafollicular locations. CD8 hCXCR5 T cells were present throughout the follicles with some observed near infected T FH In contrast, untransduced CD8 T cells were found in the extrafollicular T-cell zone. Our ability to direct localization of unselected CD8 T cells into B-cell follicles using CXCR5 expression provides a strategy to place highly effective virus-specific CD8 T cells into these AIDS virus sanctuaries and potentially suppress residual viral replication. IMPORTANCE AIDS virus persistence in individuals under effective drug therapy or those who spontaneously control viremia remains an obstacle to definitive treatment. Infected follicular helper CD4 T cells, T FH , present inside B-cell follicles represent a

  12. Role of atypical chemokine receptor ACKR2 in experimental oral squamous cell carcinogenesis.

    Science.gov (United States)

    da Silva, Janine Mayra; Dos Santos, Tálita Pollyanna Moreira; Saraiva, Adriana Machado; Fernandes de Oliveira, Ana Laura; Garlet, Gustavo Pompermaier; Batista, Aline Carvalho; de Mesquita, Ricardo Alves; Russo, Remo Castro; da Silva, Tarcília Aparecida

    2018-03-14

    Chemokines and chemokine receptors are critical in oral tumourigenesis. The atypical chemokine receptor ACKR2 is a scavenger of CC chemokines controlling the availability of these molecules at tumour sites, but the role of ACKR2 in the context of oral carcinogenesis is unexplored. In this study, wild-type (WT) and ACKR2 deficient mice (ACKR2 -/- ) were treated with chemical carcinogen 4-nitroquinoline-1-oxide (4NQO) for induction of oral carcinogenesis. Tongues were collected for macro and microscopic analysis and to evaluate the expression of ACKRs, CC chemokines and its receptors, inflammatory cytokines, angiogenic factors, adhesion molecules and extracellular matrix components. An increased expression of ACKR2 in squamous cell carcinoma (SCC) lesions of 4NQO-treated WT mice was observed. No significant differences were seen in the ACKR1, ACKR3 and ACKR4 mRNA expression comparing SCC lesions from WT and ACKR2 -/- treated mice. Significantly higher expression of CCL2, IL-6 and IL-17 was detected in ACKR2 -/- treated mice. In contrast, the expression of other CC-chemokines, and receptors, angiogenic factors, adhesion molecules and extracellular matrix components were similarly increased in SCC lesions of both groups. Clinical and histopathological analysis revealed no differences in inflammatory cell recruitment and in the SCC incidence comparing WT and ACKR2 -/- treated mice. The results suggest that ACKR2 expression regulates inflammation in tumour-microenvironment but the absence of ACKR2 does not impact chemically-induced oral carcinogenesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Polyfunctional response by ImmTAC (IMCgp100) redirected CD8+and CD4+T cells.

    Science.gov (United States)

    Boudousquie, Caroline; Bossi, Giovanna; Hurst, Jacob M; Rygiel, Karolina A; Jakobsen, Bent K; Hassan, Namir J

    2017-11-01

    The success of immune system-based cancer therapies depends on a broad immune response engaging a range of effector cells and mechanisms. Immune mobilizing monoclonal T cell receptors (TCRs) against cancer (ImmTAC™ molecules: fusion proteins consisting of a soluble, affinity enhanced TCR and an anti-CD3 scFv antibody) were previously shown to redirect CD8 + and CD4 + T cells against tumours. Here we present evidence that IMCgp100 (ImmTAC recognizing a peptide derived from the melanoma-specific protein, gp100, presented by HLA-A*0201) efficiently redirects and activates effector and memory cells from both CD8 + and CD4 + repertoires. Using isolated subpopulations of T cells, we find that both terminally differentiated and effector memory CD8 + T cells redirected by IMCgp100 are potent killers of melanoma cells. Furthermore, CD4 + effector memory T cells elicit potent cytotoxic activity leading to melanoma cell killing upon redirection by IMCgp100. The majority of T cell subsets belonging to both the CD8 + and CD4 + repertoires secrete key pro-inflammatory cytokines (tumour necrosis factor-α, interferon-γ, interleukin-6) and chemokines (macrophage inflammatory protein-1α-β, interferon-γ-inducible protein-10, monocyte chemoattractant protein-1). At an individual cell level, IMCgp100-redirected T cells display a polyfunctional phenotype, which is a hallmark of a potent anti-cancer response. This study demonstrates that IMCgp100 induces broad immune responses that extend beyond the induction of CD8 + T cell-mediated cytotoxicity. These findings are of particular importance because IMCgp100 is currently undergoing clinical trials as a single agent or in combination with check point inhibitors for patients with malignant melanoma. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

  14. Neutrophil trails guide influenza-specific CD8⁺ T cells in the airways.

    Science.gov (United States)

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Capece, Tara; Bae, Seyeon; Miller, Richard; Topham, David J; Kim, Minsoo

    2015-09-04

    During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells are unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8(+) T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditionally depleted mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8(+) T cell recruitment and effector functions. Collectively, these results suggest that neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8(+) T cell migration and localization in influenza-infected tissues. Copyright © 2015, American Association for the Advancement of Science.

  15. Neutrophil trails guide influenza-specific CD8+ T cells in the airways

    Science.gov (United States)

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Capece, Tara; Bae, Seyeon; Miller, Richard; Topham, David J.; Kim, Minsoo

    2016-01-01

    During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells is unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8+ T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditional knock-out mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8+ T cell recruitment and effector functions. Collectively, these results suggest neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8+ T cell migration and localization in influenza-infected tissues. PMID:26339033

  16. Molecular requirements for inhibition of the chemokine receptor CCR8--probe-dependent allosteric interactions

    DEFF Research Database (Denmark)

    Rummel, Pia Cwarzko; Arfelt, K N; Baumann, L

    2012-01-01

    Here we present a novel series of CCR8 antagonists based on a naphthalene-sulfonamide structure. This structure differs from the predominant pharmacophore for most small-molecule CC-chemokine receptor antagonists, which in fact activate CCR8, suggesting that CCR8 inhibition requires alternative...

  17. Bicyclams, selective antagonists of the human chemokine receptor CXCR4, potently inhibit feline immunodeficiency virus replication

    NARCIS (Netherlands)

    Horzinek, M.C.; Egberink, H.F.; Clercq, E. de; Vliet, A.L.W. van; Balzarini, J.; Bridger, G.J.; Henson, G.; Schols, D.

    1999-01-01

    Bicyclams are low-molecular-weight anti-human immunodeficiency virus (HIV) agents that have been shown to act as potent and selective CXC chemokine receptor 4 (CXCR4) antagonists. Here, we demonstrate that bicyclams are potent inhibitors of feline immunodeficiency virus (FIV) replication when

  18. Design, synthesis, and functionalization of dimeric peptides targeting chemokine receptor CXCR4.

    NARCIS (Netherlands)

    Demmer, O.; Dijkgraaf, I.; Schumacher, U.; Marinelli, L.; Cosconati, S.; Gourni, E.; Wester, H.J.; Kessler, H.

    2011-01-01

    The chemokine receptor CXCR4 is a critical regulator of inflammation and immune surveillance, and it is specifically implicated in cancer metastasis and HIV-1 infection. On the basis of the observation that several of the known antagonists remarkably share a C(2) symmetry element, we constructed

  19. Partial functional complementation between human and mouse cytomegalovirus chemokine receptor homologues

    DEFF Research Database (Denmark)

    Farrell, Helen E; Abraham, Alexander M; Cardin, Rhonda D

    2011-01-01

    The human cytomegalovirus (CMV) proteins US28 and UL33 are homologous to chemokine receptors (CKRs). Knockout of the mouse CMV M33 protein (UL33 homologue) results in substantial attenuation of salivary gland infection/replication and reduced efficiency of reactivation from tissue explants. M33...

  20. Molecular determinants of receptor binding and signaling by the CX3C chemokine fractalkine

    DEFF Research Database (Denmark)

    Mizoue, L S; Sullivan, S K; King, D S

    2001-01-01

    , but not all, pathways required for migration. Fractalkine also binds the human cytomegalovirus receptor US28, and analysis of the mutants indicates that US28 recognizes many of the same epitopes of fractalkine as CX3CR1. Comparison of the binding surfaces of fractalkine and the CC chemokine MCP-1 reveals...

  1. Biased signaling of G protein-coupled receptors - From a chemokine receptor CCR7 perspective

    DEFF Research Database (Denmark)

    Jørgensen, Astrid Sissel; Rosenkilde, Mette M; Hjortø, Gertrud M

    2018-01-01

    findings related to ligand- and tissue-biased signaling of CCR7 and summarize what is known about bias at other chemokine receptors. CCR7 is expressed by a subset of T-cells and by mature dendritic cells (DCs). Together with its two endogenous ligands CCL19 and CCL21, of which the carboxy terminal tail...... of CCL21 displays an extraordinarily strong glycosaminoglycan (GAG) binding, CCR7 plays a central role in coordinating the meeting between mature antigen presenting DCs and naïve T-cells which normally takes place in the lymph nodes (LNs). This process is a prerequisite for the initiation of an antigen......-specific T-cell mediated immune response. Thus CCR7 and its ligands are key players in initiating cell-based immune responses. CCL19 and CCL21 display differential interaction- and docking-modes for CCR7 leading to stabilization of different CCR7 conformations and hereby preferential activation of distinct...

  2. A study of chemokines, chemokine receptors and interleukin-6 in patients with panic disorder, personality disorders and their co-morbidity.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna M; Just, Marek J; Szromek, Adam R; Araszkiewicz, Aleksander

    2016-08-01

    Stress may induce inflammatory changes in the immune system and activate pro-inflammatory cytokines and their receptors by activating the hypothalamic-pituitary-adrenal axis. 460 hospitalized patients with panic disorders (PD) and/or personality disorders (P) were studied. The study group comprised subjects with PD, avoidant personality disorder (APD), borderline personality disorder (BPD), obsessive-compulsive personality disorder (OCPD), and concomitant (PD+APD; PD+BPD; PD+OCPD). Each study group consisted of 60 subjects (30 females and 30 males). The control group included 20 females and 20 males without any history of mental disorder. ELISA was used to assess the levels of chemokines: CCL-5/RANTES (regulated on activation, normal T-cell expressed and secreted), CXCL-12/SDF-1 (stromal derived factor), their receptors CXCR-5 (C-C chemokine receptor type-5), CXCR-4 (chemokine C-X-C motif receptor-4), and IL-6. Statistically significant differences in the levels of CCL-5 and CCR-5 were revealed between all study groups. The greatest differences were found between the groups with PD+OCPD and PD+APD. Moreover, concomitance of PD with P significantly increased the level of chemokines and their receptors in all study groups versus the subjects with P alone. The results of the study show differences between the groups. To be specific, inflammatory markers were more elevated in the study groups than the controls. Therefore, chemokines and chemokine receptors may be used as inflammatory markers in patients with PD co-existent with P to indicate disease severity. PD was found to be a factor in maintaining inflammatory activity in the immune system in patients with P. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  3. Dengue virus requires the CC-chemokine receptor CCR5 for replication and infection development.

    Science.gov (United States)

    Marques, Rafael E; Guabiraba, Rodrigo; Del Sarto, Juliana L; Rocha, Rebeca F; Queiroz, Ana Luiza; Cisalpino, Daniel; Marques, Pedro E; Pacca, Carolina C; Fagundes, Caio T; Menezes, Gustavo B; Nogueira, Maurício L; Souza, Danielle G; Teixeira, Mauro M

    2015-08-01

    Dengue is a mosquito-borne disease that affects millions of people worldwide yearly. Currently, there is no vaccine or specific treatment available. Further investigation on dengue pathogenesis is required to better understand the disease and to identify potential therapeutic targets. The chemokine system has been implicated in dengue pathogenesis, although the specific role of chemokines and their receptors remains elusive. Here we describe the role of the CC-chemokine receptor CCR5 in Dengue virus (DENV-2) infection. In vitro experiments showed that CCR5 is a host factor required for DENV-2 replication in human and mouse macrophages. DENV-2 infection induces the expression of CCR5 ligands. Incubation with an antagonist prevents CCR5 activation and reduces DENV-2 positive-stranded (+) RNA inside macrophages. Using an immunocompetent mouse model of DENV-2 infection we found that CCR5(-/-) mice were resistant to lethal infection, presenting at least 100-fold reduction of viral load in target organs and significant reduction in disease severity. This phenotype was reproduced in wild-type mice treated with CCR5-blocking compounds. Therefore, CCR5 is a host factor required for DENV-2 replication and disease development. Targeting CCR5 might represent a therapeutic strategy for dengue fever. These data bring new insights on the association between viral infections and the chemokine receptor CCR5. © 2015 John Wiley & Sons Ltd.

  4. Detection and Tracking of NY-ESO-1-Specific CD8+ T Cells by High-Throughput T Cell Receptor β (TCRB) Gene Rearrangements Sequencing in a Peptide-Vaccinated Patient.

    Science.gov (United States)

    Miyai, Manami; Eikawa, Shingo; Hosoi, Akihiro; Iino, Tamaki; Matsushita, Hirokazu; Isobe, Midori; Uenaka, Akiko; Udono, Heiichiro; Nakajima, Jun; Nakayama, Eiichi; Kakimi, Kazuhiro

    2015-01-01

    Comprehensive immunological evaluation is crucial for monitoring patients undergoing antigen-specific cancer immunotherapy. The identification and quantification of T cell responses is most important for the further development of such therapies. Using well-characterized clinical samples from a high responder patient (TK-f01) in an NY-ESO-1f peptide vaccine study, we performed high-throughput T cell receptor β-chain (TCRB) gene next generation sequencing (NGS) to monitor the frequency of NY-ESO-1-specific CD8+ T cells. We compared these results with those of conventional immunological assays, such as IFN-γ capture, tetramer binding and limiting dilution clonality assays. We sequenced human TCRB complementarity-determining region 3 (CDR3) rearrangements of two NY-ESO-1f-specific CD8+ T cell clones, 6-8L and 2F6, as well as PBMCs over the course of peptide vaccination. Clone 6-8L possessed the TCRB CDR3 gene TCRBV11-03*01 and BJ02-01*01 with amino acid sequence CASSLRGNEQFF, whereas 2F6 possessed TCRBV05-08*01 and BJ02-04*01 (CASSLVGTNIQYF). Using these two sequences as models, we evaluated the frequency of NY-ESO-1-specific CD8+ T cells in PBMCs ex vivo. The 6-8L CDR3 sequence was the second most frequent in PBMC and was present at high frequency (0.7133%) even prior to vaccination, and sustained over the course of vaccination. Despite a marked expansion of NY-ESO-1-specific CD8+ T cells detected from the first through 6th vaccination by tetramer staining and IFN-γ capture assays, as evaluated by CDR3 sequencing the frequency did not increase with increasing rounds of peptide vaccination. By clonal analysis using 12 day in vitro stimulation, the frequency of B*52:01-restricted NY-ESO-1f peptide-specific CD8+ T cells in PBMCs was estimated as only 0.0023%, far below the 0.7133% by NGS sequencing. Thus, assays requiring in vitro stimulation might be underestimating the frequency of clones with lower proliferation potential. High-throughput TCRB sequencing using NGS

  5. Biased and g protein-independent signaling of chemokine receptors

    DEFF Research Database (Denmark)

    Steen, Anne; Larsen, Olav; Thiele, Stefanie

    2014-01-01

    ), different receptors (with the same ligand), or different tissues or cells (for the same ligand-receptor pair). Most often biased signaling is differentiated into G protein-dependent and β-arrestin-dependent signaling. Yet, it may also cover signaling differences within these groups. Moreover, it may...

  6. CCR5 signalling, but not DARC or D6 regulatory, chemokine receptors are targeted by herpesvirus U83A chemokine which delays receptor internalisation via diversion to a caveolin-linked pathway

    Directory of Open Access Journals (Sweden)

    Gompels Ursula A

    2009-07-01

    Full Text Available Abstract Background Herpesviruses have evolved chemokines and chemokine receptors, which modulate the recruitment of human leukocytes during the inflammatory response to infection. Early post-infection, human herpesvirus 6A (HHV-6A infected cells express the chemokine receptor U51A and chemokine U83A which have complementary effects in subverting the CC-chemokine family thereby controlling anti-viral leukocyte recruitment. Here we show that, to potentiate this activity, the viral chemokine can also avoid clearance by scavenger chemokine receptors, DARC and D6, which normally regulate an inflammatory response. Conversely, U83A delays internalisation of its signalling target receptor CCR5 with diversion to caveolin rich membrane domains. This mechanism can redirect displaced human chemokines to DARC and D6 for clearance of the anti-viral inflammatory response, leaving the viral chemokine unchecked. Methods Cell models for competitive binding assays were established using radiolabeled human chemokines and cold U83A on CCR5, DARC or D6 expressing cells. Flow cytometry was used to assess specific chemotaxis of CCR5 bearing cells to U83A, and internalisation of CCR5 specific chemokine CCL4 after stimulation with U83A. Internalisation analyses were supported by confocal microscopy of internalisation and co-localisation of CCR5 with caveosome marker caveolin-1, after virus or human chemokine stimulation. Results U83A displaced efficiently human chemokines from CCR5, with a high affinity of 0.01nM, but not from DARC or D6. Signalling via CCR5 resulted in specific chemoattraction of primary human leukocytes bearing CCR5. However, U83A effective binding and signalling to CCR5 resulted in delayed internalisation and recycling up to 2 hours in the absence of continual re-stimulation. This resulted in diversion to a delayed caveolin-linked pathway rather than the rapid clathrin mediated endocytosis previously shown with human chemokines CCL3 or CCL4

  7. CCR5 signalling, but not DARC or D6 regulatory, chemokine receptors are targeted by herpesvirus U83A chemokine which delays receptor internalisation via diversion to a caveolin-linked pathway.

    Science.gov (United States)

    Catusse, Julie; Clark, David J; Gompels, Ursula A

    2009-07-30

    Herpesviruses have evolved chemokines and chemokine receptors, which modulate the recruitment of human leukocytes during the inflammatory response to infection. Early post-infection, human herpesvirus 6A (HHV-6A) infected cells express the chemokine receptor U51A and chemokine U83A which have complementary effects in subverting the CC-chemokine family thereby controlling anti-viral leukocyte recruitment. Here we show that, to potentiate this activity, the viral chemokine can also avoid clearance by scavenger chemokine receptors, DARC and D6, which normally regulate an inflammatory response. Conversely, U83A delays internalisation of its signalling target receptor CCR5 with diversion to caveolin rich membrane domains. This mechanism can redirect displaced human chemokines to DARC and D6 for clearance of the anti-viral inflammatory response, leaving the viral chemokine unchecked. Cell models for competitive binding assays were established using radiolabeled human chemokines and cold U83A on CCR5, DARC or D6 expressing cells. Flow cytometry was used to assess specific chemotaxis of CCR5 bearing cells to U83A, and internalisation of CCR5 specific chemokine CCL4 after stimulation with U83A. Internalisation analyses were supported by confocal microscopy of internalisation and co-localisation of CCR5 with caveosome marker caveolin-1, after virus or human chemokine stimulation. U83A displaced efficiently human chemokines from CCR5, with a high affinity of 0.01nM, but not from DARC or D6. Signalling via CCR5 resulted in specific chemoattraction of primary human leukocytes bearing CCR5. However, U83A effective binding and signalling to CCR5 resulted in delayed internalisation and recycling up to 2 hours in the absence of continual re-stimulation. This resulted in diversion to a delayed caveolin-linked pathway rather than the rapid clathrin mediated endocytosis previously shown with human chemokines CCL3 or CCL4. U83A diverts human chemokines from signalling, but not

  8. Human cytomegalovirus chemokine receptor US28 induces migration of cells on a CX3CL1-presenting surface

    DEFF Research Database (Denmark)

    Hjortø, Gertrud M; Kiilerich-Pedersen, Katrine; Selmeczi, David

    2013-01-01

    Human cytomegalovirus (HCMV)-encoded G protein-coupled-receptor US28 is believed to participate in virus dissemination through modulation of cell migration and immune evasion. US28 binds different CC chemokines and the CX3C chemokine CX3CL1. Membrane-anchored CX3CL1 is expressed by immune...

  9. Low Intraprostatic DHT Promotes the Infiltration of CD8+ T Cells in BPH Tissues via Modulation of CCL5 Secretion

    Directory of Open Access Journals (Sweden)

    Yu Fan

    2014-01-01

    Full Text Available Clinical studies suggested thatandrogen might be associated with infiltrating T cells in prostate of benign prostatic hyperplasia (BPH patients, but detail of T-cell subset and mechanism still remained unclear. The present study tested the hypothesis that intraprostatic 5α-dihydrotestosterone (DHT exerts effects on T cells recruitment by BPH epithelial cells. Prostate tissues from 64 cases of BPH patients after transurethral resection of prostate (TURP were divided into 2 groups: (1 no medication history; (2 administration of 5α-reductase type II inhibitor-finasteride 5 mg daily for at least 6 months before surgery. Group 2 presented significantly higher CD8+ T cells infiltration than group 1, but no changes in CD4+ T cells (immunohistochemistry and flow cytometry. In vitro study more CD8+ T cell migrated to the prostate tissue lysates from group 2 and BPH-1 cells in low DHT condition. Transcription of chemokine (C-C motif Ligand 5 (CCL5 mRNA in BPH-1 cells and chemokine (C-C motif receptor 5 (CCR5 mRNA in CD8+ T cells were upregulated in low DHT condition (q-PCR. CCL5 expression was also identified to be higher in group 2 prostate tissues by IHC. This study suggested that intraprostatic DHT may participate in regulating inflammatory response which was induced by human prostatic epithelial cell, via modulating CCL5 secretion.

  10. T cell receptor (TCR-transgenic CD8 lymphocytes rendered insensitive to transforming growth factor beta (TGFβ signaling mediate superior tumor regression in an animal model of adoptive cell therapy

    Directory of Open Access Journals (Sweden)

    Quatromoni Jon G

    2012-06-01

    Full Text Available Abstract Tumor antigen-reactive T cells must enter into an immunosuppressive tumor microenvironment, continue to produce cytokine and deliver apoptotic death signals to affect tumor regression. Many tumors produce transforming growth factor beta (TGFβ, which inhibits T cell activation, proliferation and cytotoxicity. In a murine model of adoptive cell therapy, we demonstrate that transgenic Pmel-1 CD8 T cells, rendered insensitive to TGFβ by transduction with a TGFβ dominant negative receptor II (DN, were more effective in mediating regression of established B16 melanoma. Smaller numbers of DN Pmel-1 T cells effectively mediated tumor regression and retained the ability to produce interferon-γ in the tumor microenvironment. These results support efforts to incorporate this DN receptor in clinical trials of adoptive cell therapy for cancer.

  11. Renal Protection by Genetic Deletion of the Atypical Chemokine Receptor ACKR2 in Diabetic OVE Mice

    Directory of Open Access Journals (Sweden)

    Shirong Zheng

    2016-01-01

    Full Text Available In diabetic nephropathy (DN proinflammatory chemokines and leukocyte infiltration correlate with tubulointerstitial injury and declining renal function. The atypical chemokine receptor ACKR2 is a chemokine scavenger receptor which binds and sequesters many inflammatory CC chemokines but does not transduce typical G-protein mediated signaling events. ACKR2 is known to regulate diverse inflammatory diseases but its role in DN has not been tested. In this study, we utilized ACKR2−/− mice to test whether ACKR2 elimination alters progression of diabetic kidney disease. Elimination of ACKR2 greatly reduced DN in OVE26 mice, an established DN model. Albuminuria was significantly lower at 2, 4, and 6 months of age. ACKR2 deletion did not affect diabetic blood glucose levels but significantly decreased parameters of renal inflammation including leukocyte infiltration and fibrosis. Activation of pathways that increase inflammatory gene expression was attenuated. Human biopsies stained with ACKR2 antibody revealed increased staining in diabetic kidney, especially in some tubule and interstitial cells. The results demonstrate a significant interaction between diabetes and ACKR2 protein in the kidney. Unexpectedly, ACKR2 deletion reduced renal inflammation in diabetes and the ultimate response was a high degree of protection from diabetic nephropathy.

  12. Peroxisome Proliferator-Activated Receptor Agonists Modulate Neuropathic Pain: a Link to Chemokines?

    Directory of Open Access Journals (Sweden)

    Caroline eFreitag

    2014-08-01

    Full Text Available Chronic pain presents a widespread and intractable medical problem. While numerous pharmaceuticals are used to treat chronic pain, drugs that are safe for extended use and highly effective at treating the most severe pain do not yet exist. Chronic pain resulting from nervous system injury (neuropathic pain is common in conditions ranging from multiple sclerosis to HIV-1 infection to type II diabetes. Inflammation caused by neuropathy is believed to contribute to the generation and maintenance of neuropathic pain. Chemokines are key inflammatory mediators, several of which (MCP-1, RANTES, MIP-1α, fractalkine, SDF-1 among others have been linked to chronic, neuropathic pain in both human conditions and animal models. The important roles chemokines play in inflammation and pain make them an attractive therapeutic target. Peroxisome proliferator-activated receptors are a family of nuclear receptors known for their roles in metabolism. Recent research has revealed that PPARs also play a role in inflammatory gene repression. PPAR agonists have wide-ranging effects including inhibition of chemokine expression and pain behavior reduction in animal models. Experimental evidence suggests a connection between PPAR agonists' pain ameliorating effects and suppression of inflammatory gene expression, including chemokines. In early clinical research, one PPARα agonist, palmitoylethanolamide, shows promise in relieving chronic pain. If this link can be better established, PPAR agonists may represent a new drug therapy for neuropathic pain.

  13. Role of chemokines and their receptors in viral persistence and liver damage during chronic hepatitis C virus infection

    Science.gov (United States)

    Larrubia, Juan R; Benito-Martínez, Selma; Calvino, Miryam; Sanz-de-Villalobos, Eduardo; Parra-Cid, Trinidad

    2008-01-01

    Chemokines produced in the liver during hepatitis C virus (HCV) infection induce migration of activated T cells from the periphery to infected parenchyma. The milieu of chemokines secreted by infected hepatocytes is predominantly associated with the T-helper/T-cytotoxic type-1 cell (Th1/Tc1) response. These chemokines consist of CCL3 (macrophage inflammatory protein-1α; MIP-1α), CCL4 (MIP-1β), CCL5 (regulated on activation normal T cell expressed and secreted; RANTES), CXCL10 (interferon-γ−inducible protein-10; IP-10), CXCL11 (interferon-inducible T-cell α chemoattractant; I-TAC), and CXCL9 (monokine induced by interferon γ; Mig) and they recruit T cells expressing either CCR5 or CXCR3 chemokine receptors. Intrahepatic and peripheral blood levels of these chemokines are increased during chronic hepatitis C. The interaction between chemokines and their receptors is essential in recruiting HCV-specific T cells to control the infection. When the adaptive immune response fails in this task, non-specific T cells without the capacity to control the infection are also recruited to the liver, and these are ultimately responsible for the persistent hepatic damage. The modulation of chemokine receptor expression and chemokine secretion could be a viral escape mechanism to avoid specific T cell migration to the liver during the early phase of infection, and to maintain liver viability during the chronic phase, by impairing non-specific T cell migration. Some chemokines and their receptors correlate with liver damage, and CXCL10 (IP-10) and CXCR3 levels have shown a clinical utility as predictors of treatment response outcome. The regulation of chemokines and their receptors could be a future potential therapeutic target to decrease liver inflammation and to increase specific T cell migration to the infected liver. PMID:19084927

  14. Comparison of chemokines (CCL-5 and SDF-1), chemokine receptors (CCR-5 and CXCR-4) and IL-6 levels in patients with different severities of depression.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna; Just, Marek J; Moś, Danuta; Araszkiewicz, Aleksander

    2014-10-01

    Depression can be perceived as a psychoneuroimmunological disorder in which cytokines affecting the body's neurochemical and neuroendocrine functions play an important role. Among cytokines, chemokines participating in activation of the inflammatory response are considered to be crucial. 160 men and women were enrolled in the study. 120 of them were diagnosed with various types of depression. The mean age was 45.2 ± 4.5 years (range: 19-47 years). The control group consisted of 40 healthy individuals. The average age in this group was 42.4 ± 4.1 years. Plasma levels of chemokines and their receptors (CCL-5 - RANTES and CXCR-5, SDF-1 and CXCR-4), as well as of IL-6, were assessed by ELISA. There was an increase in SDF-1 and CCL-5 levels in women and men with different severities of depression, versus the control group. Also, an increase in the IL-6 levels, CXCR4 and CCR-5 receptors was observed in both women and men with all types of depression. Levels of SDF-1 and CCL-5 chemokines, as well as of CCR-5 and CXCR4 chemokine receptors, were higher in women than in men. The results of this study indicate the need for assessment of CCL-5 and SDF-1 chemokines levels, as they are likely markers of developing depression. Early measurement of these chemokines levels may be helpful in choosing the best pharmacotherapy. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. Anti-CD8 antibodies can trigger CD8+ T-cell effector function in the absence of TCR engagement and improve pMHCI tetramer staining

    Science.gov (United States)

    Clement, Mathew; Ladell, Kristin; Ekeruche-Makinde, Julia; Miles, John J.; Edwards, Emily S. J.; Dolton, Garry; Williams, Tamsin; Schauenburg, Andrea J. A.; Cole, David K.; Lauder, Sarah N.; Gallimore, Awen M.; Godkin, Andrew J.; Burrows, Scott R.; Price, David A.; Sewell, Andrew K.; Wooldridge, Linda

    2011-01-01

    CD8+ T-cells recognize immunogenic peptides presented at the cell surface bound to major histocompatibility complex class I (MHCI) molecules. Antigen recognition involves the binding of both T-cell receptor (TCR) and CD8 co-receptor to the same peptide-MHCI (pMHCI) ligand. Specificity is determined by the TCR, whereas CD8 mediates effects on antigen sensitivity. Anti-CD8 antibodies have been used extensively to examine the role of CD8 in CD8+ T-cell activation. However, as previous studies have yielded conflicting results, it is unclear from the literature whether anti-CD8 antibodies per se are capable of inducing effector function. Here, we report on the ability of seven monoclonal anti-human CD8 antibodies to activate six human CD8+ T-cell clones with a total of five different specificities. Six out of seven anti-human CD8 antibodies tested did not activate CD8+ T-cells. In contrast, one anti-human CD8 antibody, OKT8, induced effector function in all CD8+ T-cells examined. Moreover, OKT8 was found to enhance TCR/pMHCI on-rates and, as a consequence, could be used to improve pMHCI tetramer staining and the visualization of antigen-specific CD8+ T-cells. The anti-mouse CD8 antibodies, CT-CD8a and CT-CD8b, also activated CD8+ T-cells despite opposing effects on pMHCI tetramer staining. The observed heterogeneity in the ability of anti-CD8 antibodies to trigger T-cell effector function provides an explanation for the apparent incongruity observed in previous studies and should be taken into consideration when interpreting results generated with these reagents. Furthermore, the ability of antibody-mediated CD8-engagement to deliver an activation signal underscores the importance of CD8 in CD8+ T-cell signalling. PMID:21677135

  16. The viral KSHV chemokine vMIP-II inhibits the migration of Naive and activated human NK cells by antagonizing two distinct chemokine receptors.

    Directory of Open Access Journals (Sweden)

    Rachel Yamin

    2013-08-01

    Full Text Available Natural killer (NK cells are innate immune cells able to rapidly kill virus-infected and tumor cells. Two NK cell populations are found in the blood; the majority (90% expresses the CD16 receptor and also express the CD56 protein in intermediate levels (CD56(Dim CD16(Pos while the remaining 10% are CD16 negative and express CD56 in high levels (CD56(Bright CD16(Neg. NK cells also reside in some tissues and traffic to various infected organs through the usage of different chemokines and chemokine receptors. Kaposi's sarcoma-associated herpesvirus (KSHV is a human virus that has developed numerous sophisticated and versatile strategies to escape the attack of immune cells such as NK cells. Here, we investigate whether the KSHV derived cytokine (vIL-6 and chemokines (vMIP-I, vMIP-II, vMIP-III affect NK cell activity. Using transwell migration assays, KSHV infected cells, as well as fusion and recombinant proteins, we show that out of the four cytokine/chemokines encoded by KSHV, vMIP-II is the only one that binds to the majority of NK cells, affecting their migration. We demonstrate that vMIP-II binds to two different receptors, CX3CR1 and CCR5, expressed by naïve CD56(Dim CD16(Pos NK cells and activated NK cells, respectively. Furthermore, we show that the binding of vMIP-II to CX3CR1 and CCR5 blocks the binding of the natural ligands of these receptors, Fractalkine (Fck and RANTES, respectively. Finally, we show that vMIP-II inhibits the migration of naïve and activated NK cells towards Fck and RANTES. Thus, we present here a novel mechanism in which KSHV uses a unique protein that antagonizes the activity of two distinct chemokine receptors to inhibit the migration of naïve and activated NK cells.

  17. The viral KSHV chemokine vMIP-II inhibits the migration of Naive and activated human NK cells by antagonizing two distinct chemokine receptors.

    Science.gov (United States)

    Yamin, Rachel; Kaynan, Noa S; Glasner, Ariella; Vitenshtein, Alon; Tsukerman, Pinchas; Bauman, Yoav; Ophir, Yael; Elias, Shlomo; Bar-On, Yotam; Gur, Chamutal; Mandelboim, Ofer

    2013-08-01

    Natural killer (NK) cells are innate immune cells able to rapidly kill virus-infected and tumor cells. Two NK cell populations are found in the blood; the majority (90%) expresses the CD16 receptor and also express the CD56 protein in intermediate levels (CD56(Dim) CD16(Pos)) while the remaining 10% are CD16 negative and express CD56 in high levels (CD56(Bright) CD16(Neg)). NK cells also reside in some tissues and traffic to various infected organs through the usage of different chemokines and chemokine receptors. Kaposi's sarcoma-associated herpesvirus (KSHV) is a human virus that has developed numerous sophisticated and versatile strategies to escape the attack of immune cells such as NK cells. Here, we investigate whether the KSHV derived cytokine (vIL-6) and chemokines (vMIP-I, vMIP-II, vMIP-III) affect NK cell activity. Using transwell migration assays, KSHV infected cells, as well as fusion and recombinant proteins, we show that out of the four cytokine/chemokines encoded by KSHV, vMIP-II is the only one that binds to the majority of NK cells, affecting their migration. We demonstrate that vMIP-II binds to two different receptors, CX3CR1 and CCR5, expressed by naïve CD56(Dim) CD16(Pos) NK cells and activated NK cells, respectively. Furthermore, we show that the binding of vMIP-II to CX3CR1 and CCR5 blocks the binding of the natural ligands of these receptors, Fractalkine (Fck) and RANTES, respectively. Finally, we show that vMIP-II inhibits the migration of naïve and activated NK cells towards Fck and RANTES. Thus, we present here a novel mechanism in which KSHV uses a unique protein that antagonizes the activity of two distinct chemokine receptors to inhibit the migration of naïve and activated NK cells.

  18. Strong Expression of Chemokine Receptor CXCR4 by Renal Cell Carcinoma Correlates with Advanced Disease

    Directory of Open Access Journals (Sweden)

    Thomas C. Wehler

    2008-01-01

    Full Text Available Diverse chemokines and their receptors have been associated with tumor growth, tumor dissemination, and local immune escape. In different tumor entities, the level of chemokine receptor CXCR4 expression has been linked with tumor progression and decreased survival. The aim of this study was to evaluate the influence of CXCR4 expression on the progression of human renal cell carcinoma. CXCR4 expression of renal cell carcinoma was assessed by immunohistochemistry in 113 patients. Intensity of CXCR4 expression was correlated with both tumor and patient characteristics. Human renal cell carcinoma revealed variable intensities of CXCR4 expression. Strong CXCR4 expression of renal cell carcinoma was significantly associated with advanced T-status (P=.039, tumor dedifferentiation (P = .0005, and low hemoglobin (P = .039. In summary, strong CXCR4 expression was significantly associated with advanced dedifferentiated renal cell carcinoma.

  19. The chemokine receptor CCR5 Δ32 allele in natalizumab-treated multiple sclerosis

    DEFF Research Database (Denmark)

    Møller, M; Søndergaard, H B; Koch-Henriksen, N

    2014-01-01

    OBJECTIVE: The chemokine receptor CCR5 may be important for the recruitment of pathogenic T cells to the CNS in multiple sclerosis (MS). We hypothesized that this chemokine receptor might still be important for T-cell migration during treatment with anti-very late antigen (VLA)-4 antibody. We...... therefore analysed whether natalizumab-treated MS patients carrying the CCR5 Δ32 deletion allele, which results in reduced expression of CCR5 on the cell surface, had lower disease activity. METHODS: CCR5 Δ32 was analysed in 212 natalizumab-treated MS patients. RESULTS: CCR5 Δ32 status had no significant...... impact on the frequency of relapses 1 year prior to natalizumab treatment or during the first 48 weeks of treatment. The multiple sclerosis severity score (MSSS) was significantly lower at baseline in patients carrying CCR5 Δ32 (P = 0.031). CONCLUSIONS: CCR5 Δ32 is not associated with lower disease...

  20. Molecular interaction of a potent nonpeptide agonist with the chemokine receptor CCR8

    DEFF Research Database (Denmark)

    Jensen, Pia C; Nygaard, Rie; Thiele, Stefanie

    2007-01-01

    Most nonpeptide antagonists for CC-chemokine receptors share a common pharmacophore with a centrally located, positively charged amine that interacts with the highly conserved glutamic acid (Glu) located in position 6 of transmembrane helix VII (VII:06). We present a novel CCR8 nonpeptide agonist......, 8-[3-(2-methoxyphenoxy)benzyl]-1-phenethyl-1,3,8-triaza-spiro[4.5]decan-4-one (LMD-009), that also contains a centrally located, positively charged amine. LMD-009 selectively stimulated CCR8 among the 20 identified human chemokine receptors. It mediated chemotaxis, inositol phosphate accumulation......-binding pockets of CCR8 uncovered that the binding of LMD-009 and of four analogs [2-(1-(3-(2-methoxyphenoxy)benzyl)-4-hydroxypiperidin-4-yl)benzoic acid (LMD-584), N-ethyl-2-4-methoxybenzenesulfonamide (LMD-902), N-(1-(3-(2-methoxyphenoxy)benzyl)piperidin-4-yl)-2-phenyl-4-(pyrrolidin-1yl)butanamide (LMD-268...

  1. Identification and expression analysis of an atypical chemokine receptor-2 (ACKR2)/CC chemokine binding protein-2 (CCBP2) in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Qi, Zhitao; Jiang, Yousheng; Holland, Jason W; Nie, Pin; Secombes, Christopher J; Wang, Tiehui

    2015-06-01

    Atypical chemokine receptors (ACKRs) have emerged as key components of the chemokine system, with an essential regulatory function in innate and adaptive immune responses and inflammation. In mammals ACKR2 is a 'scavenging' receptor for inflammatory CC chemokines and plays a central role in the resolution of in vivo inflammatory responses. An ACKR2 like gene has been identified and cloned in rainbow trout (Teleostei) in the present study, enabling the further identification of this molecule in another group of ray-finned teleost fish (Holostei), in a lobe-finned fish (Sarcopterygii-coelacanth), and in reptiles. The identity of these ACKR2 molecules is supported by their conserved structure, and by phylogenetic tree and synteny analysis. Trout ACKR2 is highly expressed in spleen and head kidney, suggesting a homeostatic role of this receptor in limiting the availability of its potential ligands. Trout ACKR2 expression can be modulated in vivo by bacterial and parasitic infections, and in vitro by PAMPs (poly I:C and peptidoglycan) and cytokines (IL-6, TNF-α, IFN-γ and IL-21) in a time dependent manner. These patterns of expression and modulation suggest that trout ACKR2 is regulated in a complex way and has an important role in control of the chemokine network in fish as in mammals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Target Antigen Density Governs the Efficacy of Anti-CD20-CD28-CD3 zeta Chimeric Antigen Receptor-Modified Effector CD8(+) T Cells

    NARCIS (Netherlands)

    Watanabe, Keisuke; Terakura, Seitaro; Martens, Anton C.; van Meerten, Tom; Uchiyama, Susumu; Imai, Misa; Sakemura, Reona; Goto, Tatsunori; Hanajiri, Ryo; Imahashi, Nobuhiko; Shimada, Kazuyuki; Tomita, Akihiro; Kiyoi, Hitoshi; Nishida, Tetsuya; Naoe, Tomoki; Murata, Makoto

    2015-01-01

    The effectiveness of chimeric Ag receptor (CAR)-transduced T (CAR-T) cells has been attributed to supraphysiological signaling through CARs. Second-and later-generation CARs simultaneously transmit costimulatory signals with CD3 zeta signals upon ligation, but may lead to severe adverse effects

  3. Optogenetic control of chemokine receptor signal and T-cell migration

    Science.gov (United States)

    Xu, Yuexin; Hyun, Young-Min; Lim, Kihong; Lee, Hyunwook; Cummings, Ryan J.; Gerber, Scott A.; Bae, Seyeon; Cho, Thomas Yoonsang; Lord, Edith M.; Kim, Minsoo

    2014-01-01

    Adoptive cell transfer of ex vivo-generated immune-promoting or tolerogenic T cells to either enhance immunity or promote tolerance in patients has been used with some success. However, effective trafficking of the transferred cells to the target tissue sites is the main barrier to achieving successful clinical outcomes. Here we developed a strategy for optically controlling T-cell trafficking using a photoactivatable (PA) chemokine receptor. Photoactivatable-chemokine C-X-C motif receptor 4 (PA-CXCR4) transmitted intracellular CXCR4 signals in response to 505-nm light. Localized activation of PA-CXCR4 induced T-cell polarization and directional migration (phototaxis) both in vitro and in vivo. Directing light onto the melanoma was sufficient to recruit PA-CXCR4–expressing tumor-targeting cytotoxic T cells and improved the efficacy of adoptive T-cell transfer immunotherapy, with a significant reduction in tumor growth in mice. These findings suggest that the use of photoactivatable chemokine receptors allows remotely controlled leukocyte trafficking with outstanding spatial resolution in tissues and may be feasible in other cell transfer therapies. PMID:24733886

  4. Impact of blood processing variations on Natural Killer cell frequency, activation, chemokine receptor expression and function

    Science.gov (United States)

    Naranbhai, Vivek; Bartman, Pat; Ndlovu, Dudu; Ramkalawon, Pamela; Ndung’u, Thumbi; Wilson, Douglas; Altfeld, Marcus; Carr, William H

    2011-01-01

    Understanding the role of natural killer (NK) cells in human disease pathogenesis is crucial and necessitates study of patient samples directly ex vivo. Manipulation of whole blood by density gradient centrifugation or delays in sample processing due to shipping, however, may lead to artifactual changes in immune response measures. Here, we assessed the impact of density gradient centrifugation and delayed processing of both whole blood and peripheral blood mononuclear cells (PBMC) at multiple timepoints (2–24 hrs) on flow cytometric measures of NK cell frequency, activation status, chemokine receptor expression, and effector functions. We found that density gradient centrifugation activated NK cells and modified chemokine receptor expression. Delays in processing beyond 8 hours activated NK cells in PBMC but not in whole blood. Likewise, processing delays decreased chemokine receptor (CCR4 and CCR7) expression in both PBMC and whole blood. Finally, delays in processing PBMC were associated with a decreased ability of NK cells to degranulate (as measured by CD107a expression) or secrete cytokines (IFN-γ and TNF-α). In summary, our findings suggest that density gradient centrifugation and delayed processing of PBMC can alter measures of clinically relevant NK cell characteristics including effector functions; and therefore should be taken into account in designing clinical research studies. PMID:21255578

  5. Involvement of CCR-2 chemokine receptor activation in ischemic preconditioning and postconditioning of brain in mice.

    Science.gov (United States)

    Rehni, Ashish K; Singh, Thakur Gurjeet

    2012-10-01

    The present study has been designed to investigate the potential role of CCR-2 chemokine receptor in ischemic preconditioning as well as postconditioning induced reversal of ischemia-reperfusion injury in mouse brain. Bilateral carotid artery occlusion of 17 min followed by reperfusion for 24h was employed in present study to produce ischemia and reperfusion induced cerebral injury in mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was evaluated using elevated plus-maze test and Morris water maze test. Rota rod test was employed to assess motor incoordination. Bilateral carotid artery occlusion followed by reperfusion produced cerebral infarction and impaired memory and motor co-ordination. Three preceding episodes of bilateral carotid artery occlusion for 1 min and reperfusion of 1 min were employed to elicit ischemic preconditioning of brain, while three episodes of bilateral carotid artery occlusion for 10s and reperfusion of 10s immediately after the completion of were employed to elicit ischemic postconditioning of brain. Both prior ischemic preconditioning as well as ischemic postconditioning immediately after global cerebral ischemia prevented markedly ischemia-reperfusion-induced cerebral injury as measured in terms of infarct size, loss of memory and motor coordination. RS 102895, a selective CCR-2 chemokine receptor antagonist, attenuated the neuroprotective effect of both the ischemic preconditioning as well as postconditioning. It is concluded that the neuroprotective effect of both ischemic preconditioning as well as ischemic postconditioning may involve the activation of CCR-2 chemokine receptors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Selective loss of chemokine receptor expression on leukocytes after cell isolation.

    Directory of Open Access Journals (Sweden)

    Juan C Nieto

    Full Text Available Chemokine receptors are distinctively exposed on cells to characterize their migration pattern. However, little is known about factors that may regulate their expression. To determine the optimal conditions for an accurate analysis of chemokine receptors, we compared the expression of CCR2, CCR4, CCR5, CCR6, CXCR3 and CXCR4 on different leukocyte subsets using whole blood (WB plus erythrocyte lysis and density gradient isolation (Ficoll. Most WB monocytes were CCR2+ (93.5 ± 2.9% whereas 32.8 ± 6.0% of monocytes from Ficoll-PBMC expressed CCR2 (p<0.001. Significant reductions of CCR6 and CXCR3 on monocytes were also observed after Ficoll isolation (WB: 46.4 ± 7.5% and 57.1 ± 5.5%; Ficoll: 29.5 ± 2.2% and 5.4 ± 4.3% respectively (p<0.01. Although comparable percentages of WB and Ficoll-PBMC monocytes expressed CCR4, CCR5 and CXCR4, Ficoll isolation significantly reduced the levels of CXCR4 (WB: MFI 5 ± 0.4 and Ficoll: MFI 3.3 ± 0.1 (p<0.05. Similarly to monocytes, CCR2, CXCR3 and CXCR4 were also reduced on lymphocytes. In addition, Ficoll isolation significantly reduced the percentage of CCR4 positive lymphocytes (WB: 90.2 ± 4.5% and Ficoll: 55 ± 4.1% (p<0.01. The loss of expression of chemokine receptors after isolation of monocytes was not dependent on either the anticoagulant or the density gradient method. It was irreversible and could not be restored by LPS activation or in vitro macrophage differentiation. Experiments tagged with anti-CCR2 antibodies prior to density gradient isolation demonstrated that Ficoll internalized chemokine receptors. The method for cell isolation may alter not only the expression of certain chemokine receptors but also the respective functional migration assay. The final choice to analyze their expression should therefore depend on the receptor to be measured.

  7. CD8 beta chain influences CD8 alpha chain-associated Lck kinase activity

    OpenAIRE

    1995-01-01

    The CD8 molecule plays an important role in the differentiation of CD8+ T cells in the thymus and in their normal function in the periphery. CD8 exists on the cell surface in two forms, the alpha alpha homodimer and the alpha beta heterodimer. Recent studies indicate an important role for the CD8 beta chain in thymic development of CD8+ T cells and suggest that signaling via CD8 alpha beta may be distinct from CD8 alpha alpha. To better understand these differences, we introduced the CD8 beta...

  8. The chemokine receptor CXCR3 and its splice variant are expressed in human airway epithelial cells.

    Science.gov (United States)

    Kelsen, Steven G; Aksoy, Mark O; Yang, Yi; Shahabuddin, Syed; Litvin, Judith; Safadi, Fayez; Rogers, Thomas J

    2004-09-01

    Activation of the chemokine receptor CXCR3 by its cognate ligands induces several differentiated cellular responses important to the growth and migration of a variety of hematopoietic and structural cells. In the human respiratory tract, human airway epithelial cells (HAEC) release the CXCR3 ligands Mig/CXCL9, IP-10/CXCL10, and I-TAC/CXCL11. Simultaneous expression of CXCR3 by HAEC would have important implications for the processes of airway inflammation and repair. Accordingly, in the present study we sought to determine whether HAEC also express the classic CXCR3 chemokine receptor CXCR3-A and its splice variant CXCR3-B and hence may respond in autocrine fashion to its ligands. We found that cultured HAEC (16-HBE and tracheocytes) constitutively expressed CXCR3 mRNA and protein. CXCR3 mRNA levels assessed by expression array were approximately 35% of beta-actin expression. In contrast, CCR3, CCR4, CCR5, CCR8, and CX3CR1 were <5% beta-actin. Both CXCR3-A and -B were expressed. Furthermore, tracheocytes freshly harvested by bronchoscopy stained positively for CXCR3 by immunofluorescence microscopy, and 68% of cytokeratin-positive tracheocytes (i.e., the epithelial cell population) were positive for CXCR3 by flow cytometry. In 16-HBE cells, CXCR3 receptor density was approximately 78,000 receptors/cell when assessed by competitive displacement of 125I-labeled IP-10/CXCL10. Finally, CXCR3 ligands induced chemotactic responses and actin reorganization in 16-HBE cells. These findings indicate constitutive expression by HAEC of a functional CXC chemokine receptor, CXCR3. Our data suggest the possibility that autocrine activation of CXCR3 expressed by HAEC may contribute to airway inflammation and remodeling in obstructive lung disease by regulating HAEC migration.

  9. Supraphysiologic control over HIV-1 replication mediated by CD8 T cells expressing a re-engineered CD4-based chimeric antigen receptor.

    Directory of Open Access Journals (Sweden)

    Rachel S Leibman

    2017-10-01

    Full Text Available HIV is adept at avoiding naturally generated T cell responses; therefore, there is a need to develop HIV-specific T cells with greater potency for use in HIV cure strategies. Starting with a CD4-based chimeric antigen receptor (CAR that was previously used without toxicity in clinical trials, we optimized the vector backbone, promoter, HIV targeting moiety, and transmembrane and signaling domains to determine which components augmented the ability of T cells to control HIV replication. This re-engineered CAR was at least 50-fold more potent in vitro at controlling HIV replication than the original CD4 CAR, or a TCR-based approach, and substantially better than broadly neutralizing antibody-based CARs. A humanized mouse model of HIV infection demonstrated that T cells expressing optimized CARs were superior at expanding in response to antigen, protecting CD4 T cells from infection, and reducing viral loads compared to T cells expressing the original, clinical trial CAR. Moreover, in a humanized mouse model of HIV treatment, CD4 CAR T cells containing the 4-1BB costimulatory domain controlled HIV spread after ART removal better than analogous CAR T cells containing the CD28 costimulatory domain. Together, these data indicate that potent HIV-specific T cells can be generated using improved CAR design and that CAR T cells could be important components of an HIV cure strategy.

  10. Stimulation of oral fibroblast chemokine receptors identifies CCR3 and CCR4 as potential wound healing targets

    Science.gov (United States)

    Buskermolen, Jeroen K.; Roffel, Sanne

    2017-01-01

    The focus of this study was to determine which chemokine receptors are present on oral fibroblasts and whether these receptors influence proliferation, migration, and/or the release of wound healing mediators. This information may provide insight into the superior wound healing characteristics of the oral mucosa. The gingiva fibroblasts expressed 12 different chemokine receptors (CCR3, CCR4, CCR6, CCR9, CCR10, CXCR1, CXCR2, CXCR4, CXCR5, CXCR7, CX3CR1, and XCR1), as analyzed by flow cytometry. Fourteen corresponding chemokines (CCL5, CCL15, CCL20, CCL22, CCL25, CCL27, CCL28, CXCL1, CXCL8, CXCL11, CXCL12, CXCL13, CX3CL1, and XCL1) were used to study the activation of these receptors on gingiva fibroblasts. Twelve of these fourteen chemokines stimulated gingiva fibroblast migration (all except for CXCL8 and CXCL12). Five of the chemokines stimulated proliferation (CCL5/CCR3, CCL15/CCR3, CCL22/CCR4, CCL28/CCR3/CCR10, and XCL1/XCR1). Furthermore, CCL28/CCR3/CCR10 and CCL22/CCR4 stimulation increased IL‐6 secretion and CCL28/CCR3/CCR10 together with CCL27/CCR10 upregulated HGF secretion. Moreover, TIMP‐1 secretion was reduced by CCL15/CCR3. In conclusion, this in‐vitro study identifies chemokine receptor‐ligand pairs which may be used in future targeted wound healing strategies. In particular, we identified the chemokine receptors CCR3 and CCR4, and the mucosa specific chemokine CCL28, as having an predominant role in oral wound healing by increasing human gingiva fibroblast proliferation, migration, and the secretion of IL‐6 and HGF and reducing the secretion of TIMP‐1. PMID:28387445

  11. Altered expression of glial markers, chemokines, and opioid receptors in the spinal cord of type 2 diabetic monkeys.

    Science.gov (United States)

    Kiguchi, Norikazu; Ding, Huiping; Peters, Christopher M; Kock, Nancy D; Kishioka, Shiroh; Cline, J Mark; Wagner, Janice D; Ko, Mei-Chuan

    2017-01-01

    Neuroinflammation is a pathological condition that underlies diabetes and affects sensory processing. Given the high prevalence of pain in diabetic patients and crosstalk between chemokines and opioids, it is pivotal to know whether neuroinflammation-associated mediators are dysregulated in the central nervous system of diabetic primates. Therefore, the aim of this study was to investigate whether mRNA expression levels of glial markers, chemokines, and opioid receptors are altered in the spinal cord and thalamus of naturally occurring type 2 diabetic monkeys (n=7) compared with age-matched non-diabetic monkeys (n=6). By using RT-qPCR, we found that mRNA expression levels of both GFAP and IBA1 were up-regulated in the spinal dorsal horn (SDH) of diabetic monkeys compared with non-diabetic monkeys. Among all chemokines, expression levels of three chemokine ligand-receptor systems, i.e., CCL2-CCR2, CCL3-CCR1/5, and CCL4-CCR5, were up-regulated in the SDH of diabetic monkeys. Moreover, in the SDH, seven additional chemokine receptors, i.e., CCR4, CCR6, CCR8, CCR10, CXCR3, CXCR5, and CXCR6, were also up-regulated in diabetic monkeys. In contrast, expression levels of MOP, KOP, and DOP, but not NOP receptors, were down-regulated in the SDH of diabetic monkeys, and the thalamus had fewer changes in the glial markers, chemokines and opioids. These findings indicate that neuroinflammation, manifested as glial activation and simultaneous up-regulation of multiple chemokine ligands and receptors, seems to be permanent in type 2 diabetic monkeys. As chemokines and opioids are important pain modulators, this first-in-primate study provides a translational bridge for determining the functional efficacy of spinal drugs targeting their signaling cascades. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The herpesvirus 8-encoded chemokine vMIP-II, but not the poxvirus-encoded chemokine MC148, inhibits the CCR10 receptor

    DEFF Research Database (Denmark)

    Lüttichau, H R; Lewis, I C; Gerstoft, J

    2001-01-01

    The viral chemokine antagonist vMIP-II encoded by human herpesvirus 8 (HHV8) and MC148 encoded by the poxvirus - Molluscum contagiosum - were tested against the newly identified chemokine receptor CCR10. As the CCR10 ligand ESkine / CCL27 had the highest identity to MC148 and because both...... chemokines are expressed in the skin we suspected MC148 to block CCR10. However, in calcium mobilization assays we found MC148 unable to block CCR10 in micromolar concentrations in contrast to vMIP-II. (125)I-MC148 was only able to bind to CCR8, but not to CCR10, CCR11, CXCR6 / BONZO, APJ, DARC or the orphan...... receptors BOB, EBI-II, GPR4, GPR17, HCR or RDC1. We conclude that MC148 is a highly selective CCR8 antagonist conceivably optimized to interfere with NK cell and monocyte invasion, whereas the broad-spectrum antagonist vMIP-II protects HHV8 by blocking multiple receptors....

  13. Rationally designed chemokine-based toxin targeting the viral G protein-coupled receptor US28 potently inhibits cytomegalovirus infection in vivo

    DEFF Research Database (Denmark)

    Spiess, Katja; Jeppesen, Mads G.; Malmgaard-Clausen, Mikkel

    2015-01-01

    to target the human viral pathogen, human cytomegalovirus (HCMV), on the basis of its expression of the 7TM G protein-coupled chemokine receptor US28. The virus origin of US28 provides an exceptional chemokine-binding profile with high selectivity and improved binding for the CX3C chemokine, CX3CL1...

  14. Spread of Psoriasiform Inflammation to Remote Tissues Is Restricted by the Atypical Chemokine Receptor ACKR2.

    Science.gov (United States)

    Shams, Kave; Wilson, Gillian J; Singh, Mark; van den Bogaard, Ellen H; Le Brocq, Michelle L; Holmes, Susan; Schalkwijk, Joost; Burden, A David; McKimmie, Clive S; Graham, Gerard J

    2017-01-01

    Elucidating the poorly defined mechanisms by which inflammatory lesions are spatially restricted in vivo is of critical importance in understanding skin disease. Chemokines are the principal regulators of leukocyte migration and are essential in the initiation and maintenance of inflammation. The membrane-bound psoriasis-associated atypical chemokine receptor 2 (ACKR2) binds, internalizes and degrades most proinflammatory CC-chemokines. Here we investigate the role of ACKR2 in limiting the spread of cutaneous psoriasiform inflammation to sites that are remote from the primary lesion. Circulating factors capable of regulating ACKR2 function at remote sites were identified and examined using a combination of clinical samples, relevant primary human cell cultures, in vitro migration assays, and the imiquimod-induced model of psoriasiform skin inflammation. Localized inflammation and IFN-γ together up-regulate ACKR2 in remote tissues, protecting them from the spread of inflammation. ACKR2 controls inflammatory T-cell chemotaxis and positioning within the skin, preventing an epidermal influx that is associated with lesion development. Our results have important implications for our understanding of how spatial restriction is imposed on the spread of inflammatory lesions and highlight systemic ACKR2 induction as a therapeutic strategy in the treatment and prevention of psoriasis and potentially a broad range of other immune-mediated diseases. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Discovery and mapping of an intracellular antagonist binding site at the chemokine receptor CCR2

    DEFF Research Database (Denmark)

    Zweemer, Annelien J M; Bunnik, Julia; Veenhuizen, Margo

    2014-01-01

    The chemokine receptor CCR2 is a G protein-coupled receptor that is involved in many diseases characterized by chronic inflammation, and therefore a large variety of CCR2 small molecule antagonists has been developed. On the basis of their chemical structures these antagonists can roughly...... be divided into two groups with most likely two topographically distinct binding sites. The aim of the current study was to identify the binding site of one such group of ligands, exemplified by three allosteric antagonists, CCR2-RA-[R], JNJ-27141491, and SD-24. We first used a chimeric CCR2/CCR5 receptor...... approach to obtain insight into the binding site of the allosteric antagonists and additionally introduced eight single point mutations in CCR2 to further characterize the putative binding pocket. All constructs were studied in radioligand binding and/or functional IP turnover assays, providing evidence...

  16. Cord blood Vα24-Vβ11 natural killer T cells display a Th2-chemokine receptor profile and cytokine responses.

    Directory of Open Access Journals (Sweden)

    Susanne Harner

    Full Text Available BACKGROUND: The fetal immune system is characterized by a Th2 bias but it is unclear how the Th2 predominance is established. Natural killer T (NKT cells are a rare subset of T cells with immune regulatory functions and are already activated in utero. To test the hypothesis that NKT cells are part of the regulatory network that sets the fetal Th2 predominance, percentages of Vα24(+Vβ11(+ NKT cells expressing Th1/Th2-related chemokine receptors (CKR were assessed in cord blood. Furthermore, IL-4 and IFN-γ secreting NKT cells were quantified within the single CKR(+ subsets. RESULTS: Cord blood NKT cells expressed the Th2-related CCR4 and CCR8 at significantly higher frequencies compared to peripheral blood NKT cells from adults, while CXCR3(+ and CCR5(+ cord blood NKT cells (Th1-related were present at lower percentages. Within CD4(negCD8(neg (DN NKT cells, the frequency of IL-4 producing NKT cells was significantly higher in cord blood, while frequencies of IFN-γ secreting DN NKT cells tended to be lower. A further subanalysis showed that the higher percentage of IL-4 secreting DN NKT cells was restricted to CCR3(+, CCR4(+, CCR5(+, CCR6(+, CCR7(+, CCR8(+ and CXCR4(+ DN subsets in cord blood. This resulted in significantly decreased IFN-γ /IL-4 ratios of CCR3(+, CCR6(+ and CCR8(+ cord blood DN NKT cells. Sequencing of VA24AJ18 T cell receptor (TCR transcripts in sorted cord blood Vα24Vβ11 cells confirmed the invariant TCR alpha-chain ruling out the possibility that these cells represent an unusual subset of conventional T cells. CONCLUSIONS: Despite the heterogeneity of cord blood NKT cells, we observed a clear Th2-bias at the phenotypic and functional level which was mainly found in the DN subset. Therefore, we speculate that NKT cells are important for the initiation and control of the fetal Th2 environment which is needed to maintain tolerance towards self-antigens as well as non-inherited maternal antigens.

  17. T-cells in the cerebrospinal fluid express a similar repertoire of inflammatory chemokine receptors in the absence or presence of CNS inflammation

    DEFF Research Database (Denmark)

    Kivisäkk, P; Trebst, C; Liu, Z

    2002-01-01

    It is believed that chemokines and their receptors are involved in trafficking of T-cells to the central nervous system (CNS). The aim of the current study was to define the expression on cerebrospinal fluid (CSF) T-cells of six chemokine receptors associated with trafficking to sites of inflamma......It is believed that chemokines and their receptors are involved in trafficking of T-cells to the central nervous system (CNS). The aim of the current study was to define the expression on cerebrospinal fluid (CSF) T-cells of six chemokine receptors associated with trafficking to sites...

  18. G protein-coupled receptor kinase 2 negatively regulates chemokine signaling at a level downstream from G protein subunits

    NARCIS (Netherlands)

    Jimenez-Sainz, MC; Murga, C; Kavelaars, A; Jurado-Pueyo, M; Krakstad, BF; Heijnen, CJ; Mayor, F; Aragay, AM

    The G protein-coupled receptor kinase 2 (GRK2) phosphorylates and desensitizes ligand-activated G protein-coupled-receptors. Here, evidence is shown for a novel role of GRK2 in regulating chemokine-mediated signals. The presence of increased levels of GRK2 in human embryonic kidney (HEK) 293 cells

  19. CXCR3 expression defines a novel subset of innate CD8+ T cells that enhance immunity against bacterial infection and cancer upon stimulation with IL-15

    Science.gov (United States)

    Oghumu, Steve; Terrazas, Cesar A.; Varikuti, Sanjay; Kimble, Jennifer; Vadia, Stephen; Yu, Lianbo; Seveau, Stephanie; Satoskar, Abhay R.

    2015-01-01

    Innate CD8+ T cells are a heterogeneous population with developmental pathways distinct from conventional CD8+ T cells. However, their biology, classification, and functions remain incompletely understood. We recently demonstrated the existence of a novel population of chemokine (C-X-C motif) receptor 3 (CXCR3)-positive innate CD8+ T cells. Here, we investigated the functional properties of this subset and identified effector molecules and pathways which mediate their function. Adoptive transfer of IL-15 activated CXCR3+ innate CD8+ T cells conferred increased protection against Listeria monocytogenes infection in susceptible IFN-γ−/− mice compared with similarly activated CXCR3− subset. This was associated with enhanced proliferation and IFN-γ production in CXCR3+ cells. Further, CXCR3+ innate cells showed enhanced cytotoxicity against a tumor cell line in vitro. In depth analysis of the CXCR3+ subset showed increased gene expression of Ccl5, Klrc1, CtsW, GP49a, IL-2Rβ, Atp5e, and Ly6c but reduced IFN-γR2 and Art2b. Ingenuity pathway analysis revealed an up-regulation of genes associated with T-cell activation, proliferation, cytotoxicity, and translational initiation in CXCR3+ populations. Our results demonstrate that CXCR3 expression in innate CD8+ T cells defines a subset with enhanced cytotoxic potential and protective antibacterial immune functions. Immunotherapeutic approaches against infectious disease and cancer could utilize CXCR3+ innate CD8+ T-cell populations as novel clinical intervention strategies.—Oghumu, S., Terrazas, C. A., Varikuti, S., Kimble, J., Vadia, S., Yu, L., Seveau, S., Satoskar, A. R. CXCR3 expression defines a novel subset of innate CD8+ T cells that enhance immunity against bacterial infection and cancer upon stimulation with IL-15. PMID:25466888

  20. Chemokine Ligand 5 (CCL5 and chemokine receptor (CCR5 genetic variants and prostate cancer risk among men of African Descent: a case-control study

    Directory of Open Access Journals (Sweden)

    Kidd LaCreis R

    2012-11-01

    Full Text Available Abstract Background Chemokine and chemokine receptors play an essential role in tumorigenesis. Although chemokine-associated single nucleotide polymorphisms (SNPs are associated with various cancers, their impact on prostate cancer (PCA among men of African descent is unknown. Consequently, this study evaluated 43 chemokine-associated SNPs in relation to PCA risk. We hypothesized inheritance of variant chemokine-associated alleles may lead to alterations in PCA susceptibility, presumably due to variations in antitumor immune responses. Methods Sequence variants were evaluated in germ-line DNA samples from 814 African-American and Jamaican men (279 PCA cases and 535 controls using Illumina’s Goldengate genotyping system. Results Inheritance of CCL5 rs2107538 (AA, GA+AA and rs3817655 (AA, AG, AG+AA genotypes were linked with a 34-48% reduction in PCA risk. Additionally, the recessive and dominant models for CCR5 rs1799988 and CCR7 rs3136685 were associated with a 1.52-1.73 fold increase in PCA risk. Upon stratification, only CCL5 rs3817655 and CCR7 rs3136685 remained significant for the Jamaican and U.S. subgroups, respectively. Conclusions In summary, CCL5 (rs2107538, rs3817655 and CCR5 (rs1799988 sequence variants significantly modified PCA susceptibility among men of African descent, even after adjusting for age and multiple comparisons. Our findings are only suggestive and require further evaluation and validation in relation to prostate cancer risk and ultimately disease progression, biochemical/disease recurrence and mortality in larger high-risk subgroups. Such efforts will help to identify genetic markers capable of explaining disproportionately high prostate cancer incidence, mortality, and morbidity rates among men of African descent.

  1. Annulus fibrosus cells express and utilize C-C chemokine receptor 5 (CCR5) for migration.

    Science.gov (United States)

    Liu, Weijun; Liu, David; Zheng, Justin; Shi, Peng; Chou, Po-Hsin; Oh, Chundo; Chen, Di; An, Howard S; Chee, Ana

    2017-05-01

    Disc degeneration is associated with the progressive loss of the proteoglycan content of the intervertebral disc, decreased matrix synthesis, higher concentrations of proteolytic enzymes, and increased levels of proinflammatory cytokines. In previous studies, we have shown that C-C chemokine ligand (CCL)2, CCL3, and CCL5 are highly expressed by cultured nucleus pulposus (NP) and annulus fibrosus (AF) cells that have been treated by interleukin-1. The major function of these chemokines is to recruit immune cells into the disc. It is unclear if disc cells can respond to these chemokines. Recent studies by Phillips et al. (2015) showed that NP cells express a number of cytokines and chemokine receptors. The purpose of this study is to determine the gene and protein expression of C-C chemokine receptor (CCR)1, CCR2, and CCR5 in NP and AF cells, and to test if these receptors can respond to their ligands in these cells by cell signaling and migration. This is an in vitro study. For RNA, surface expression, and cell signaling studies, human cells were isolated from the NP and AF tissues collected after spine surgery or from donated spine segments (Gift of Hope Human Donor & Tissue Network of Illinois) and cultured in monolayer. The gene expression of human CCR1, CCR2, and CCR5 was analyzed using real-time polymerase chain reaction. The surface expression of CCR1, CCR2, and CCR5 was analyzed using flow cytometry and fluorescently tagged antibodies specific for these proteins. Extracellular signal-regulated kinase (ERK) phosphorylation was analyzed from the cell lysates of NP and AF cells treated with CCL2 and CCL5 for 1 hour using enzyme-linked immunosorbent assay. Migration of primary rabbit AF cells was assayed using 8-µm Corning Transwell inserts in the presence or absence of CCL5. This study was partially funded by a North American Spine Society 2014 Basic Research Grant Award ($50,000). RNA analysis showed that gene expression of CCR1, CCR2, and CCR5 was evident in

  2. Pharmacological characterization of AZD5069, a slowly reversible CXC chemokine receptor 2 antagonist.

    Science.gov (United States)

    Nicholls, David J; Wiley, Katherine; Dainty, Ian; MacIntosh, Fraser; Phillips, Caroline; Gaw, Alasdair; Mårdh, Carina Kärrman

    2015-05-01

    In normal physiologic responses to injury and infection, inflammatory cells enter tissue and sites of inflammation through a chemotactic process regulated by several families of proteins, including inflammatory chemokines, a family of small inducible cytokines. In neutrophils, chemokines chemokine (CXC motif) ligand 1 (CXCL1) and CXCL8 are potent chemoattractants and activate G protein-coupled receptors CXC chemokine receptor 1 (CXCR1) and CXCR2. Several small-molecule antagonists of CXCR2 have been developed to inhibit the inflammatory responses mediated by this receptor. Here, we present the data describing the pharmacology of AZD5069 [N-(2-(2,3-difluorobenzylthio)-6-((2R,3S)-3,4-dihydroxybutan-2-yloxy)[2,4,5,6-(13)C4, 1,3-(15)N2]pyrimidin-4-yl)azetidine-1-sulfonamide,[(15)N2,(13)C4]N-(2-(2,3-difluoro-6-[3H]-benzylthio)-6-((2R,3S)-3,4-dihydroxybutan-2-yloxy)pyrimidin-4-yl)azetidine-1-sulfonamide], a novel antagonist of CXCR2. AZD5069 was shown to inhibit binding of radiolabeled CXCL8 to human CXCR2 with a pIC50 value of 9.1. Furthermore, AZD5069 inhibited neutrophil chemotaxis, with a pA2 of approximately 9.6, and adhesion molecule expression, with a pA2 of 6.9, in response to CXCL1. AZD5069 was a slowly reversible antagonist of CXCR2 with effects of time and temperature evident on the pharmacology and binding kinetics. With short incubation times, AZD5069 appeared to have an antagonist profile with insurmountable antagonism of calcium response curves. This behavior was also observed in vivo in an acute lipopolysaccharide-induced lung inflammation model. Altogether, the data presented here show that AZD5069 represents a novel, potent, and selective CXCR2 antagonist with potential as a therapeutic agent in inflammatory conditions. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  3. Onbaekwon Suppresses Colon Cancer Cell Invasion by Inhibiting Expression of the CXC Chemokine Receptor 4.

    Science.gov (United States)

    Kim, Buyun; Yoon, Jaewoo; Yoon, Seong Woo; Park, Byoungduck

    2017-06-01

    Cysteine X cysteine (CXC) chemokine receptor 4 (CXCR4) and C-X-C motif chemokine 12 (CXCL12) were originally identified as chemoattractants between immune cells and sites of inflammation. Since studies have validated an increased level of CXCL12 and its receptor in patients with colorectal cancers, CXCL12/CXCR4 axis has been considered as a valuable marker of cancer metastasis. Therefore, identification of CXCR4 inhibitors has great potential to abrogate tumor metastasis. Onbaekwon (OBW) is a complex herbal formula that is derived from the literature of traditional Korean medicine Dongeuibogam. In this study, we demonstrated that OBW suppressed CXCR4 expression in various cancer cell types in a concentration- and time-dependent manner. Both proteasomal and lysosomal inhibitors had no effect to prevent the OBW-induced suppression of CXCR4, suggesting that the inhibitory effect of OBW was not due to proteolytic degradation but occurred at the transcriptional level. Electrophoretic mobility shift assay further confirmed that OBW could block endogenous activation of nuclear factor kappa B, a key transcription factor that regulates the expression of CXCR4 in colon cancer cells. Consistent with the aforementioned molecular basis, OBW abolished cell invasion induced by CXCL12 in colon cancer cells. Together, our results suggest that OBW, as a novel inhibitor of CXCR4, could be a promising therapeutic agent contributing to cancer treatment.

  4. Humoral Immune Pressure Selects for HIV-1 CXC-chemokine Receptor 4-using Variants

    Directory of Open Access Journals (Sweden)

    Nina Lin

    2016-06-01

    Full Text Available Although both C-C chemokine receptor 5 (CCR5- and CXC chemokine receptor 4 (CXCR4-using HIV-1 strains cause AIDS, the emergence of CXCR4-utilizing variants is associated with an accelerated decline in CD4+ T cells. It remains uncertain if CXCR4-using viruses hasten disease or if these variants only emerge after profound immunological damage. We show that exclusively CXCR4- as compared to cocirculating CCR5-utilizing variants are less sensitive to neutralization by both contemporaneous autologous plasma and plasma pools from individuals that harbor only CCR5-using HIV-1. The CXCR4-utilizing variants, however, do not have a global antigenic change because they remain equivalently susceptible to antibodies that do not target coreceptor binding domains. Studies with envelope V3 loop directed antibodies and chimeric envelopes suggest that the neutralization susceptibility differences are potentially influenced by the V3 loop. In vitro passage of a neutralization sensitive CCR5-using virus in the presence of autologous plasma and activated CD4+ T cells led to the emergence of a CXCR4-utilizing virus in 1 of 3 cases. These results suggest that in some but not necessarily all HIV-1 infected individuals humoral immune pressure against the autologous virus selects for CXCR4-using variants, which potentially accelerates disease progression. Our observations have implications for using antibodies for HIV-1 immune therapy.

  5. Discovery and Characterization of Biased Allosteric Agonists of the Chemokine Receptor CXCR3

    DEFF Research Database (Denmark)

    Milanos, Lampros; Brox, Regine; Frank, Theresa

    2016-01-01

    In this work we report a design, synthesis, and detailed functional characterization of unique strongly biased allosteric agonists of CXCR3 that contain tetrahydroisoquinoline carboxamide cores. Compound 11 (FAUC1036) is the first strongly biased allosteric agonist of CXCR3 that selectively induces...... weak chemotaxis and leads to receptor internalization and the β-arrestin 2 recruitment with potency comparable to that of the chemokine CXCL11 without any activation of G proteins. A subtle structural change (addition of a methoxy group, 14 (FAUC1104)) led to a contrasting biased allosteric partial...... agonist that activated solely G proteins, induced chemotaxis, but failed to induce receptor internalization or β-arrestin 2 recruitment. Concomitant structure-activity relationship studies indicated very steep structure-activity relationships, which steer the ligand bias between the β-arrestin 2 and G...

  6. A novel intracellular pool of LFA-1 is critical for asymmetric CD8+ T cell activation and differentiation.

    Science.gov (United States)

    Capece, Tara; Walling, Brandon L; Lim, Kihong; Kim, Kyun-Do; Bae, Seyeon; Chung, Hung-Li; Topham, David J; Kim, Minsoo

    2017-11-06

    The integrin lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) is a key T cell adhesion receptor that mediates stable interactions with antigen-presenting cell (APC), as well as chemokine-mediated migration. Using our newly generated CD11a-mYFP knock-in mice, we discovered that naive CD8 + T cells reserve a significant intracellular pool of LFA-1 in the uropod during migration. Intracellular LFA-1 quickly translocated to the cell surface with antigenic stimulus. Importantly, the redistribution of intracellular LFA-1 at the contact with APC was maintained during cell division and led to an unequal inheritance of LFA-1 in divided T cells. The daughter CD8 + T cells with disparate LFA-1 expression showed different patterns of migration on ICAM-1, APC interactions, and tissue retention, as well as altered effector functions. In addition, we identified Rab27 as an important regulator of the intracellular LFA-1 translocation. Collectively, our data demonstrate that an intracellular pool of LFA-1 in naive CD8 + T cells plays a key role in T cell activation and differentiation. © 2017 Capece et al.

  7. C-X-C chemokine receptor type 4 (CXCR4) is a key receptor for chicken primordial germ cell migration.

    Science.gov (United States)

    Lee, Jeong Hyo; Park, Jeong-Woong; Kim, Si Won; Park, Joonghoon; Park, Tae Sub

    2017-12-15

    In mammals, germ cells originate outside of the developing gonads and follow a unique migration pattern through the embryonic tissue toward the genital ridges. Many studies have attempted to identify critical receptors and factors involved in germ cell migration. However, relatively few reports exist on germ cell receptors and chemokines that are involved in germ cell migration in avian species. In the present study, we investigated the specific migratory function of C-X-C chemokine receptor type 4 (CXCR4) in chicken primordial germ cells (PGCs). We induced loss-of-function via a frameshift mutation in the CXCR4 gene in chicken PGCs using clustered regularly interspaced short palindromic repeat-CRISPR-associated protein 9 (CRISPR/Cas9) genome editing. The migratory capacity of CXCR4 knockout PGCs was significantly reduced in vivo after transplantation into recipient embryos. However, CXCR4-expressing somatic cell lines, such as chicken DT40 and DF1, failed to migrate into the developing gonads, suggesting that another key factor(s) is necessary for targeting and settlement of PGCs into the genital ridges. In conclusion, we show that CXCR4 plays a critical role in the migration of chicken germ cells.

  8. T cell factor-1 controls the lifetime of CD4+ CD8+ thymocytes in vivo and distal T cell receptor α-chain rearrangement required for NKT cell development.

    Directory of Open Access Journals (Sweden)

    Archna Sharma

    Full Text Available Natural killer T (NKT cells are a component of innate and adaptive immune systems implicated in immune, autoimmune responses and in the control of obesity and cancer. NKT cells develop from common CD4+ CD8+ double positive (DP thymocyte precursors after the rearrangement and expression of T cell receptor (TCR Vα14-Jα18 gene. Temporal regulation and late appearance of Vα14-Jα18 rearrangement in immature DP thymocytes has been demonstrated. However, the precise control of lifetime of DP thymocytes in vivo that enables distal rearrangements remains incompletely defined. Here we demonstrate that T cell factor (TCF-1, encoded by the Tcf7 gene, is critical for the extended lifetime of DP thymocytes. TCF-1-deficient DP thymocytes fail to undergo TCR Vα14-Jα18 rearrangement and produce significantly fewer NKT cells. Ectopic expression of Bcl-xL permits Vα14-Jα18 rearrangement and rescues NKT cell development. We report that TCF-1 regulates expression of RORγt, which regulates DP thymocyte survival by controlling expression of Bcl-xL. We posit that TCF-1 along with its cofactors controls the lifetime of DP thymocytes in vivo.

  9. Placental Chemokine Receptor D6 Is Functionally Impaired in Pre-Eclampsia.

    Directory of Open Access Journals (Sweden)

    Chiara Tersigni

    Full Text Available Pre-eclampsia (PE is a major cause of maternal and perinatal morbidity and mortality worldwide. It is defined by new onset of hypertension and proteinuria after the 20th week of gestation and characterized by systemic exaggerated inflammatory response. D6 is a chemokines scavenger receptor that binds with high affinity CC chemokines, internalizes and targets the ligands for degradation. It is expressed in trophoblast-derived tissues and prevents excessive placenta leukocyte infiltration.The aim of this study was to investigate the expression and function of D6 in human placentae from pre-eclamptic and healthy pregnant women.Plasma levels of D6-binding CC chemokines (CCL-2, CCL-3, CCL-4, CCL-7, CCL-11 and pro-inflammatory cytokines (IL-6, TNF-α, CRP were analyzed in 37 healthy pregnant women and 38 patients with PE by multiplex bead assay. Higher circulating levels of CCL7, CCL11, IL-6, (p<0.0001 and CRP (p<0.05 were observed in PE women compared to controls. Levels of circulating CCL4 were decreased in PE (p<0.001, while no significant differences of CCL2, CCL3 or TNF-α levels were detected. Immunofluorescent staining of placental sections showed higher expression of D6 receptor in the PE syncytiotrophoblast. Confocal and Western blot (WB analyses revealed a prevalent distribution of D6 in trophoblast cells membranes in PE. Increased activation of D6 intracellular pathway was observed by Western blot analyses of p-LIMK and p-cofilin in trophoblast cell lysates. D6 functional assays showed reduced scavenging of CCL2 in PE cells compared to controls. Since actin filaments spatial assembling is essential for D6 intracellular trafficking and scavenging activity, we investigated by confocal microscopy trophoblast cytoskeleton organization and we observed a dramatic disarrangement in PE compared to controls.our results suggest membrane distribution of D6 receptor on trophoblast cell membranes in PE, together with reduced functionality, probably due

  10. A Mucosal and Cutaneous Chemokine Ligand for the Lymphocyte Chemoattractant Receptor GPR15

    Directory of Open Access Journals (Sweden)

    Borja Ocón

    2017-09-01

    Full Text Available Chemoattractants control lymphocyte recruitment from the blood, contributing to the systemic organization of the immune system. The G protein-linked receptor GPR15 mediates lymphocyte homing to the large intestines and skin. Here we show that the 9 kDa CC-motif containing cationic polypeptide AP57/colon-derived sushi containing domain-2 binding factor (CSBF, encoded by C10orf99 in the human and 2610528A11Rik in the mouse, functions as a chemokine ligand for GPR15 (GPR15L. GPR15L binds GPR15 and attracts GPR15-expressing T cells including lymphocytes in colon-draining lymph nodes and Vγ3+ thymic precursors of dermal epithelial T cells. Patterns of GPR15L expression by epithelial cells in adult mice and humans suggest a homeostatic role for the chemokine in lymphocyte localization to the large intestines, as well as a role in homing to the epidermis during wound healing or inflammation. GPR15L is also significantly expressed in squamous mucosa of the oral cavity and esophagus with still poorly defined regulation. Identification of the chemotactic activity of GPR15L adds to its reported antibacterial and tumor cell growth regulatory functions and suggests the potential of targeting GPR15L–GPR15 interactions for modulation of mucosal and cutaneous inflammation.

  11. A computational study of the chemokine receptor CXCR1 bound with interleukin-8

    Science.gov (United States)

    Wang, Yang; Severin Lupala, Cecylia; Wang, Ting; Li, Xuanxuan; Yun, Ji-Hye; Park, Jae-hyun; Jin, Zeyu; Lee, Weontae; Tan, Leihan; Liu, Haiguang

    2018-03-01

    CXCR1 is a G-protein coupled receptor, transducing signals from chemokines, in particular the interleukin-8 (IL8) molecules. This study combines homology modeling and molecular dynamics simulation methods to study the structure of CXCR1-IL8 complex. By using CXCR4-vMIP-II crystallography structure as the homologous template, CXCR1-IL8 complex structure was constructed, and then refined using all-atom molecular dynamics simulations. Through extensive simulations, CXCR1-IL8 binding poses were investigated in detail. Furthermore, the role of the N-terminal of CXCR1 receptor was studied by comparing four complex models differing in the N-terminal sequences. The results indicate that the receptor N-terminal affects the binding of IL8 significantly. With a shorter N-terminal domain, the binding of IL8 to CXCR1 becomes unstable. The homology modeling and simulations also reveal the key receptor-ligand residues involved in the electrostatic interactions known to be vital for complex formation. Project supported by the National Natural Science Foundation of China (Grant Nos. 11575021, U1530401, and U1430237) and the National Research Foundation of Korea (Grant Nos. NRF-2017R1A2B2008483 and NRF-2016R1A6A3A04010213).

  12. Fractalkine receptor chemokine (CX3CR1) influences on cervical and lumbar disc herniation

    Science.gov (United States)

    Oh, In-Soo; Suh, Dong-Whan; Park, Sung-Ryeoll; Ha, Kee-Yong

    2015-01-01

    Background: Herniation of nuclear or disc material along with, inflammatory chemokines such as prostaglandin E2, interleukin-6, matrix metalloproteinase and nitric oxide has definite correlation, possibly they are over produced. CX3CL1 and its receptor (CX3CR1) are part of chemokine system involved in leukocyte recruitment and adhesion in chronic inflammatory disease, but its role in spinal herniated nucleus pulposus (HNP) is unknown. We evaluated the expression of CX3CL1 and CX3CR1 in patients with disc herniation to clarify the role of CX3CL1 and CX3CR1 in the disc degeneration and to compare between cervical and lumbar HNP. Materials and Methods: The mRNA concentrations of CX3CL1/CX3CR1 chemokine were analyzed in the surgically obtained disc specimens from C-HNP (n = 13) and L-HNP (n = 13) by real-time polymerase chain reaction (PCR). The localization of CX3CL1/CX3CR1 chemokine in the disc of C-HNP and L-HNP patients was determined using immunohistochemical study. Blood samples from patients with C-HNP and L-HNP patients were stained for CX3CR1 with flow cytometric analysis. Results: The CX3CL1 positive cell ratio in the discs was observed in both groups by immunohistochemical study. CX3CR1 was strongly expressed on endothelial cells in C-spine disc, but sparely expressed in L-spine disc. There was greater CX3CR1 mRNA expression in C-HNP patients than in L-HNP patients as quantified by reversal transcription-PCR (P = 0.010). CX3CR1 positive cell frequencies and CX3CR1 expression levels were increased in CD4 (+) T-cells and natural killer (NK) cells from patients with C-HNP (P = 0.210 and P = 0.040). Conclusions: This study identified that increases in CX3CL1 and CX3CR1-expressing cells are significantly related to pathomechanism of HNP for the first time. Especially, CD4 (+) T-cells and NK cells expressing CX3CR1 may play an important role in developing C-HNP. PMID:26015616

  13. Acetylation of the Cd8 Locus by KAT6A Determines Memory T Cell Diversity

    Directory of Open Access Journals (Sweden)

    Dane M. Newman

    2016-09-01

    Full Text Available How functionally diverse populations of pathogen-specific killer T cells are generated during an immune response remains unclear. Here, we propose that fine-tuning of CD8αβ co-receptor levels via histone acetylation plays a role in lineage fate. We show that lysine acetyltransferase 6A (KAT6A is responsible for maintaining permissive Cd8 gene transcription and enabling robust effector responses during infection. KAT6A-deficient CD8+ T cells downregulated surface CD8 co-receptor expression during clonal expansion, a finding linked to reduced Cd8α transcripts and histone-H3 lysine 9 acetylation of the Cd8 locus. Loss of CD8 expression in KAT6A-deficient T cells correlated with reduced TCR signaling intensity and accelerated contraction of the effector-like memory compartment, whereas the long-lived memory compartment appeared unaffected, a result phenocopied by the removal of the Cd8 E8I enhancer element. These findings suggest a direct role of CD8αβ co-receptor expression and histone acetylation in shaping functional diversity within the cytotoxic T cell pool.

  14. The Timing of Stimulation and IL-2 Signaling Regulate Secondary CD8 T Cell Responses

    Science.gov (United States)

    Khan, Shaniya H.; Martin, Matthew D.; Starbeck-Miller, Gabriel R.; Xue, Hai-Hui; Harty, John T.; Badovinac, Vladimir P.

    2015-01-01

    Abstract Memory CD8 T cells provide protection to immune hosts by eliminating pathogen-infected cells during re-infection. While parameters influencing the generation of primary (1°) CD8 T cells are well established, the factors controlling the development of secondary (2°) CD8 T cell responses remain largely unknown. Here, we address the mechanisms involved in the generation and development of 2° memory (M) CD8 T cells. We observed that the time at which 1° M CD8 T cells enter into immune response impacts their fate and differentiation into 2° M CD8 T cells. Late-entry of 1° M CD8 T cells into an immune response (relative to the onset of infection) not only facilitated the expression of transcription factors associated with memory formation in 2° effector CD8 T cells, but also influenced the ability of 2° M CD8 T cells to localize within the lymph nodes, produce IL-2, and undergo Ag-driven proliferation. The timing of stimulation of 1° M CD8 T cells also impacted the duration of expression of the high-affinity IL-2 receptor (CD25) on 2° effector CD8 T cells and their sensitivity to IL-2 signaling. Importantly, by blocking or enhancing IL-2 signaling in developing 2° CD8 T cells, we provide direct evidence for the role of IL-2 in controlling the differentiation of Ag-driven 2° CD8 T cell responses. Thus, our data suggest that the process of 1° M to 2° M CD8 T cell differentiation is not fixed and can be manipulated, a notion with relevance for the design of future prime-boost vaccination approaches. PMID:26431533

  15. Asymptomatic memory CD8+ T cells

    Science.gov (United States)

    Khan, Arif Azam; Srivastava, Ruchi; Lopes, Patricia Prado; Wang, Christine; Pham, Thanh T; Cochrane, Justin; Thai, Nhi Thi Uyen; Gutierrez, Lucas; BenMohamed, Lbachir

    2014-01-01

    Generation and maintenance of high quantity and quality memory CD8+ T cells determine the level of protection from viral, bacterial, and parasitic re-infections, and hence constitutes a primary goal for T cell epitope-based human vaccines and immunotherapeutics. Phenotypically and functionally characterizing memory CD8+ T cells that provide protection against herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2) infections, which cause blinding ocular herpes, genital herpes, and oro-facial herpes, is critical for better vaccine design. We have recently categorized 2 new major sub-populations of memory symptomatic and asymptomatic CD8+ T cells based on their phenotype, protective vs. pathogenic function, and anatomical locations. In this report we are discussing a new direction in developing T cell-based human herpes vaccines and immunotherapeutics based on the emerging new concept of “symptomatic and asymptomatic memory CD8+ T cells.” PMID:24499824

  16. GluVII:06--a highly conserved and selective anchor point for non-peptide ligands in chemokine receptors

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Schwartz, Thue W

    2006-01-01

    A majority of small molecule non-peptide ligands for chemokine receptors in general are characterized by the presence of one or two centrally located, positively charged nitrogen atoms and these compounds are also often of relatively similar elongated overall structure with terminal aromatic...

  17. Reversed binding of a small molecule ligand in homologous chemokine receptors - differential role of extracellular loop 2

    DEFF Research Database (Denmark)

    Jensen, P C; Thiele, S; Steen, A

    2012-01-01

    The majority of small molecule compounds targeting chemokine receptors share a similar pharmacophore with a centrally located aliphatic positive charge and flanking aromatic moieties. Here we describe a novel piperidine-based compound with structural similarity to previously described CCR8-specif...

  18. Dysregulation of chemokine receptor expression and function in leukocytes from ALS patients.

    Science.gov (United States)

    Perner, Caroline; Perner, Florian; Stubendorff, Beatrice; Förster, Martin; Witte, Otto W; Heidel, Florian H; Prell, Tino; Grosskreutz, Julian

    2018-03-28

    Amyotrophic lateral sclerosis (ALS) is rapidly progressive adult-onset motor neuron disease characterized by the neurodegeneration of both upper and lower motor neurons in the cortex and the spinal cord; the majority of patients succumb to respiratory failure. Although the etiology is not yet fully understood, there is compelling evidence that ALS is a multi-systemic disorder, with peripheral inflammation critically contributing to the disease process. However, the full extent and nature of this immunological dysregulation remains to be established, particularly within circulating blood cells. Therefore, the aim of the present study was to identify dysregulated inflammatory molecules in peripheral blood cells of ALS patients and analyze for functional consequences of the observed findings. To this end, we employed flow cytometry-based screening to quantify the surface expression of major chemokine receptors and integrins. A significantly increased expression of CXCR3, CXCR4, CCL2, and CCL5 was observed on T cells in ALS patients compared to healthy controls. Intriguingly, the expression was even more pronounced in patients with a slow progressive phenotype. To further investigate the functional consequences of this altered surface expression, we used a modified Boyden chamber assay to measure chemotaxis in ALS patient-derived lymphocytes. Interestingly, chemoattraction with the CXCR3-Ligand IP10 led to upregulated migratory behavior of ALS lymphocytes compared to healthy controls. Taken together, our data provides evidence for a functional dysregulation of IP10-directed chemotaxis in peripheral blood cells in ALS patients. However, whether the chemokine itself or its receptor CXCR3, or both, could serve as potential therapeutic targets in ALS requires further investigations.

  19. A macrophage inflammatory protein homolog encoded by guinea pig cytomegalovirus signals via CC chemokine receptor 1

    International Nuclear Information System (INIS)

    Penfold, Mark; Miao Zhenhua; Wang Yu; Haggerty, Shannon; Schleiss, Mark R.

    2003-01-01

    Cytomegaloviruses encode homologs of cellular immune effector proteins, including chemokines (CKs) and CK receptor-like G protein-coupled receptors (GPCRs). Sequence of the guinea pig cytomegalovirus (GPCMV) genome identified an open reading frame (ORF) which predicted a 101 amino acid (aa) protein with homology to the macrophage inflammatory protein (MIP) subfamily of CC (β) CKs, designated GPCMV-MIP. To assess functionality of this CK, recombinant GPCMV-MIP was expressed in HEK293 cells and assayed for its ability to bind to and functionally interact with a variety of GPCRs. Specific signaling was observed with the hCCR1 receptor, which could be blocked with hMIP -1α in competition experiments. Migration assays revealed that GPCMV-MIP was able to induce chemotaxis in hCCR1-L1.2 cells. Antisera raised against a GST-MIP fusion protein immunoprecipitated species of ∼12 and 10 kDa from GPCMV-inoculated tissue culture lysates, and convalescent antiserum from GPCMV-infected animals was immunoreactive with GST-MIP by ELISA assay. These results represent the first substantive in vitro characterization of a functional CC CK encoded by a cytomegalovirus

  20. Similar activation of signal transduction pathways by the herpesvirus-encoded chemokine receptors US28 and ORF74

    DEFF Research Database (Denmark)

    McLean, Katherine A; Holst, Peter J; Martini, Lene

    2004-01-01

    The virally encoded chemokine receptors US28 from human cytomegalovirus and ORF74 from human herpesvirus 8 are both constitutively active. We show that both receptors constitutively activate the transcription factors nuclear factor of activated T cells (NFAT) and cAMP response element binding...... viral gene expression similarly. As ORF74 is a known inducer of neoplasia, these findings may have important implications for cytomegalovirus-associated pathogenicity....

  1. Touch of chemokines

    Directory of Open Access Journals (Sweden)

    Xavier eBLANCHET

    2012-07-01

    Full Text Available Chemoattractant cytokines or chemokines constitute a family of structurally related proteins found in vertebrates, bacteria or viruses. So far, 48 chemokines genes have been identified in humans, which bind to around 20 chemokine receptors. These receptors belong to the seven transmembrane G-protein-coupled receptors family. Chemokines and their receptors were originally studied for their role in cellular trafficking of leukocytes during inflammation and immune surveillance as well. It is now known that they exert different functions under physiological conditions such as homeostasis, development, tissue repair, and angiogenesis but also under pathological disorders including tumorigenesis, cancer metastasis, inflammatory and autoimmune diseases. Physicochemical properties of chemokines and chemokine receptors confer them the ability to homo- and hetero-oligomerize. Many efforts are currently performed in establishing new therapeutically compounds able to target the chemokine/chemokine receptors system.In this review, we are interested in the role of chemokines in inflammatory disease and leukocyte trafficking with a focus on vascular inflammatory diseases, the operating synergism and the emerging therapeutic approaches of chemokines.

  2. Interleukin-4 mediates CD8 induction on human CD4+ T-cell clones

    NARCIS (Netherlands)

    Paliard, X.; Malefijt, R. W.; de Vries, J. E.; Spits, H.

    1988-01-01

    CD4 and CD8 antigens are simultaneously expressed on most of the cortical thymocytes, that weakly express the T-cell antigen receptor(TCR)/CD3 complex. Mature peripheral T cells, however, strongly express the TCR complex and are positive for either CD4 or CD8. Nevertheless, a small percentage of

  3. CD8 T cell memory: it takes all kinds

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    Stephen Christopher Jameson

    2012-11-01

    Full Text Available Understanding the mechanisms that regulate the differentiation and maintenance of CD8+ memory T cells is fundamental to the development of effective T cell based vaccines. Memory cell differentiation is influenced by the cytokines that accompany T cell priming, the history of previous antigen encounters, and the tissue sites into which memory cells migrate. These cues combine to influence the developing CD8+ memory pool, and recent work has revealed the importance of multiple transcription factors, metabolic molecules, and surface receptors in revealing the type of memory cell that is generated. Paired with increasingly meticulous subsetting and sorting of memory populations, we now know the CD8+ memory pool to be phenotypically and functionally heterogeneous in nature. This includes both recirculating and tissue resident memory populations, and cells with varying degrees of inherent longevity and protective function. These data point to the importance of tailored vaccine design. Here we discuss how the diversity of the memory CD8+ T cell pool challenges the notion that ‘one size fits all’ for pathogen control, and how distinct memory subsets may be suited for distinct aspects of protective immunity.

  4. Effector CD8+T cell-derived interleukin-10 enhances acute liver immunopathology.

    Science.gov (United States)

    Fioravanti, Jessica; Di Lucia, Pietro; Magini, Diletta; Moalli, Federica; Boni, Carolina; Benechet, Alexandre Pierre; Fumagalli, Valeria; Inverso, Donato; Vecchi, Andrea; Fiocchi, Amleto; Wieland, Stefan; Purcell, Robert; Ferrari, Carlo; Chisari, Francis V; Guidotti, Luca G; Iannacone, Matteo

    2017-09-01

    Besides secreting pro-inflammatory cytokines, chemokines and effector molecules, effector CD8 + T cells that arise upon acute infection with certain viruses have been shown to produce the regulatory cytokine interleukin (IL)-10 and, therefore, contain immunopathology. Whether the same occurs during acute hepatitis B virus (HBV) infection and role that IL-10 might play in liver disease is currently unknown. Mouse models of acute HBV pathogenesis, as well as chimpanzees and patients acutely infected with HBV, were used to analyse the role of CD8 + T cell-derived IL-10 in liver immunopathology. Mouse HBV-specific effector CD8 + T cells produce significant amounts of IL-10 upon in vivo antigen encounter. This is corroborated by longitudinal data in a chimpanzee acutely infected with HBV, where serum IL-10 was readily detectable and correlated with intrahepatic CD8 + T cell infiltration and liver disease severity. Unexpectedly, mouse and human CD8 + T cell-derived IL-10 was found to act in an autocrine/paracrine fashion to enhance IL-2 responsiveness, thus preventing antigen-induced HBV-specific effector CD8 + T cell apoptosis. Accordingly, the use of mouse models of HBV pathogenesis revealed that the IL-10 produced by effector CD8 + T cells promoted their own intrahepatic survival and, thus supported, rather than suppressed liver immunopathology. Effector CD8 + T cell-derived IL-10 enhances acute liver immunopathology. Altogether, these results extend our understanding of the cell- and tissue-specific role that IL-10 exerts in immune regulation. Lay summary: Interleukin-10 is mostly regarded as an immunosuppressive cytokine. We show here that HBV-specific CD8 + T cells produce IL-10 upon antigen recognition and that this cytokine enhances CD8 + T cell survival. As such, IL-10 paradoxically promotes rather than suppresses liver disease. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  5. The C-C Chemokines CCL17 and CCL22 and Their Receptor CCR4 in CNS Autoimmunity

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    Stefanie Scheu

    2017-11-01

    Full Text Available Multiple sclerosis (MS is a chronic inflammatory demyelinating disease of the central nervous system (CNS. It affects more than two million people worldwide, mainly young adults, and may lead to progressive neurological disability. Chemokines and their receptors have been shown to play critical roles in the pathogenesis of experimental autoimmune encephalomyelitis (EAE, a murine disease model induced by active immunization with myelin proteins or transfer of encephalitogenic CD4+ T cells that recapitulates clinical and neuropathological features of MS. Chemokine ligand-receptor interactions orchestrate leukocyte trafficking and influence multiple pathophysiological cellular processes, including antigen presentation and cytokine production by dendritic cells (DCs. The C-C class chemokines 17 (CCL17 and 22 (CCL22 and their C-C chemokine receptor 4 (CCR4 have been shown to play an important role in homeostasis and inflammatory responses. Here, we provide an overview of the involvement of CCR4 and its ligands in CNS autoimmunity. We review key clinical studies of MS together with experimental studies in animals that have demonstrated functional roles of CCR4, CCL17, and CCL22 in EAE pathogenesis. Finally, we discuss the therapeutic potential of newly developed CCR4 antagonists and a humanized anti-CCR4 antibody for treatment of MS.

  6. Enhanced monocyte migration to CXCR3 and CCR5 chemokines in COPD.

    Science.gov (United States)

    Costa, Claudia; Traves, Suzanne L; Tudhope, Susan J; Fenwick, Peter S; Belchamber, Kylie B R; Russell, Richard E K; Barnes, Peter J; Donnelly, Louise E

    2016-04-01

    Chronic obstructive pulmonary disease (COPD) patients exhibit chronic inflammation, both in the lung parenchyma and the airways, which is characterised by an increased infiltration of macrophages and T-lymphocytes, particularly CD8+ cells. Both cell types can express chemokine (C-X-C motif) receptor (CXCR)3 and C-C chemokine receptor 5 and the relevant chemokines for these receptors are elevated in COPD. The aim of this study was to compare chemotactic responses of lymphocytes and monocytes of nonsmokers, smokers and COPD patients towards CXCR3 ligands and chemokine (C-C motif) ligand (CCL)5. Migration of peripheral blood mononuclear cells, monocytes and lymphocytes from nonsmokers, smokers and COPD patients toward CXCR3 chemokines and CCL5 was analysed using chemotaxis assays. There was increased migration of peripheral blood mononuclear cells from COPD patients towards all chemokines studied when compared with nonsmokers and smokers. Both lymphocytes and monocytes contributed to this enhanced response, which was not explained by increased receptor expression. However, isolated lymphocytes failed to migrate and isolated monocytes from COPD patients lost their enhanced migratory capacity. Both monocytes and lymphocytes cooperate to enhance migration towards CXCR3 chemokines and CCL5. This may contribute to increased numbers of macrophages and T-cells in the lungs of COPD patients, and inhibition of recruitment using selective antagonists might be a treatment to reduce the inflammatory response in COPD.

  7. The Role of Natural Antibodies to CC Chemokine Receptor 5 in HIV Infection

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    Assunta Venuti

    2017-10-01

    Full Text Available The CC chemokine receptor 5 (CCR5 is responsible for immune and inflammatory responses by mediation of chemotactic activity in leukocytes, although it is expressed on different cell types. It has been shown to act as co-receptor for the human and simian immunodeficiency viruses (HIV-1, HIV-2, and SIV. Natural reactive antibodies (Abs recognizing first loop (ECL1 of CCR5 have been detected in several pools of immunoglobulins from healthy donors and from several cohorts of either HIV-exposed but uninfected subjects (ESN or HIV-infected individuals who control disease progression (LTNP as well. The reason of development of anti-CCR5 Abs in the absence of autoimmune disease is still unknown; however, the presence of these Abs specific for CCR5 or for other immune receptors and mediators probably is related to homeostasis maintenance. The majority of anti-CCR5 Abs is directed to HIV binding site (N-terminus and ECL2 of the receptor. Conversely, it is well known that ECL1 of CCR5 does not bind HIV; thus, the anti-CCR5 Abs directed to ECL1 elicit a long-lasting internalization of CCR5 but not interfere with HIV binding directly; these Abs block HIV infection in either epithelial cells or CD4+ T lymphocytes and the mechanism differs from those ones described for all other CCR5-specific ligands. The Ab-mediated CCR5 internalization allows the formation of a stable signalosome by interaction of CCR5, β-arrestin2 and ERK1 proteins. The signalosome degradation and the subsequent de novo proteins synthesis determine the CCR5 reappearance on the cell membrane with a very long-lasting kinetics (8 days. The use of monoclonal Abs to CCR5 with particular characteristics and mode of action may represent a novel mode to fight viral infection in either vaccinal or therapeutic strategies.

  8. Evidence of positive selection at codon sites localized in extracellular domains of mammalian CC motif chemokine receptor proteins

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    Metzger Kelsey J

    2010-05-01

    Full Text Available Abstract Background CC chemokine receptor proteins (CCR1 through CCR10 are seven-transmembrane G-protein coupled receptors whose signaling pathways are known for their important roles coordinating immune system responses through targeted trafficking of white blood cells. In addition, some of these receptors have been identified as fusion proteins for viral pathogens: for example, HIV-1 strains utilize CCR5, CCR2 and CCR3 proteins to obtain cellular entry in humans. The extracellular domains of these receptor proteins are involved in ligand-binding specificity as well as pathogen recognition interactions. In mammals, the majority of chemokine receptor genes are clustered together; in humans, seven of the ten genes are clustered in the 3p21-24 chromosome region. Gene conversion events, or exchange of DNA sequence between genes, have been reported in chemokine receptor paralogs in various mammalian lineages, especially between the cytogenetically closely located pairs CCR2/5 and CCR1/3. Datasets of mammalian orthologs for each gene were analyzed separately to minimize the potential confounding impact of analyzing highly similar sequences resulting from gene conversion events. Molecular evolution approaches and the software package Phylogenetic Analyses by Maximum Likelihood (PAML were utilized to investigate the signature of selection that has acted on the mammalian CC chemokine receptor (CCR gene family. The results of neutral vs. adaptive evolution (positive selection hypothesis testing using Site Models are reported. In general, positive selection is defined by a ratio of nonsynonymous/synonymous nucleotide changes (dN/dS, or ω >1. Results Of the ten mammalian CC motif chemokine receptor sequence datasets analyzed, only CCR2 and CCR3 contain amino acid codon sites that exhibit evidence of positive selection using site based hypothesis testing in PAML. Nineteen of the twenty codon sites putatively indentified as likely to be under positive

  9. Hepatic Chemerin and Chemokine-Like Receptor 1 Expression in Patients with Chronic Hepatitis C

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    Michał Kukla

    2014-01-01

    Full Text Available Introduction. Chemerin seems to be involved in pathogenesis of chronic hepatitis C (CHC. Hepatic expressions of chemerin and its receptor, chemokine receptor-like 1 (CMKLR1, in CHC have not been studied so far. Aim. To evaluate chemerin and CMKLR1 hepatic expression together with serum chemerin concentration in CHC patients and to assess their relationship with metabolic and histopathological abnormalities. Methods. The study included 63 nonobese CHC patients. Transcription of chemerin and CMKLR1 was assessed by quantitative real-time PCR, while serum chemerin was assessed by enzyme-linked immunosorbent assay. Results. Expression of chemerin and CMKLR1 was present in the liver of all CHC patients regardless of sex or age. This expression was not associated with necroinflammatory activity and steatosis grade, fibrosis stage, and metabolic abnormalities. There was a negative association between serum chemerin and chemerin hepatic expression (r = (−0.41, P = 0.006. Conclusion. The study for the first time confirmed a marked expression of chemerin and CMKLR1 in the liver of CHC patients. The study was performed using the homogenates of human liver tissue, so it is not possible to define whether hepatocytes or other cell types which are abundantly represented in the liver constitute the main source of chemerin and CMKLR1 mRNA.

  10. Chemokines (RANTES and MCP-1) and chemokine-receptors (CCR2 and CCR5) gene polymorphisms in Alzheimer's and Parkinson's disease.

    Science.gov (United States)

    Huerta, Cecilia; Alvarez, Victoria; Mata, Ignacio F; Coto, Eliecer; Ribacoba, René; Martínez, Carmen; Blázquez, Marta; Guisasola, Luis M; Salvador, Carlos; Lahoz, Carlos H; Peña, Joaquín

    2004-11-11

    Parkinson's disease (PD) is a complex disorder characterized by the progressive degeneration of dopaminergic neurons in the midbrain. Late-onset Alzheimer's disease (LOAD) is the most common cause of dementia in the elderly, affecting about 5% of the population older than 65 years. Several works have demonstrated the involvement of inflammation in the pathogenesis of both, PD and LOAD. Genetic susceptibility to develop PD and LOAD has also been widely recognised. Thus, functional polymorphisms at the genes encoding inflammatory proteins could influence the overall risk of developing these neurodegenerative disorders. We examined whether DNA-polymorphisms at the genes encoding chemokines MCP-1 (-2518 A/G) and RANTES (-403 A/G), and chemokine receptors 5 (CCR5, Delta32) and 2 (CCR2,V64I), were associated with the risk and/or the clinical outcome of LOAD and PD. A total of 200 PD, 326 LOAD, and 370 healthy controls were genotyped for the four polymorphisms, and genotype frequencies statistically compared. We did not find significant differences in the frequencies of the different genotypes between both groups of patients and controls. We conclude that the four DNA polymorphisms, which have been associated with several immuno-modulated diseases, did not contribute to the risk of PD or LOAD.

  11. A subset of human plasmacytoid dendritic cells expresses CD8α upon exposure to herpes simplex virus type 1

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    Philipp eSchuster

    2015-06-01

    Full Text Available Classical and plasmacytoid dendritic cells (DC play important roles in the defense against murine and human infections with herpes simplex virus (HSV. So far, CD8α expression has only been reported for murine DC. CD8α+ DC have prominent cross-presenting activities, which are enhanced by murine CD8α+ PDC. The human orthologue of murine CD8α+ DC, the CD141 (BDCA3+ DC, mainly cross-present after TLR3 ligation. We report here the serendipitous finding that a subset of human PDC upregulates CD8α upon HSV-1 stimulation, as shown by gene array and flow cytometry analyses. CD8α, not CD8ß, was expressed upon exposure. Markers of activation, migration, and costimulation were upregulated on CD8α-expressing human PDC. In these cells, increased cytokine and chemokine levels were detected that enhance development and function of T, B, and NK cells, and recruit immature DC, monocytes, and Th1 cells, respectively. Altogether, human CD8α+ PDC exhibit a highly activated phenotype and appear to recruit other immune cells to the site of inflammation. Further studies will show whether CD8α-expressing PDC contribute to antigen cross-presentation, which may be important for immune defenses against HSV infections in vitro and in vivo.

  12. Chemokines, lymphocytes, and HIV

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    Farber J.M.

    1998-01-01

    Full Text Available Chemokines are members of a family of more than 30 human cytokines whose best-described activities are as chemotactic factors for leukocytes and that are presumed to be important in leukocyte recruitment and trafficking. While many chemokines can act on lymphocytes, the roles of chemokines and their receptors in lymphocyte biology are poorly understood. The recent discoveries that chemokines can suppress infection by HIV-1 and that chemokine receptors serve, along with CD4, as obligate co-receptors for HIV-1 entry have lent urgency to studies on the relationships between chemokines and lymphocytes. My laboratory has characterized Mig and Crg-2/IP-10, chemokines that are induced by IFN-g and that specifically target lymphocytes, particularly activated T cells. We have demonstrated that the genes for these chemokines are widely expressed during experimental infections in mice with protozoan and viral pathogens, but that the patterns of mig and crg-2 expression differed, suggesting non-redundant roles in vivo. Our related studies to identify new chemokine receptors from activated lymphocytes resulted in the cloning of STRL22 and STRL33. We and others have shown that STRL22 is a receptor for the CC chemokine MIP-3a, and STRL22 has been re-named CCR6. Although STRL33 remains an orphan receptor, we have shown that it can function as a co-receptor for HIV-1 envelope glycoproteins, and that it is active with a broader range of HIV-1 envelope glycoproteins than the major co-receptors described to date. The ability of STRL33 to function with a wide variety of envelope glycoproteins may become particularly important if therapies are instituted to block other specific co-receptors. We presume that investigations into the roles of chemokines and their receptors in lymphocyte biology will provide information important for understanding the pathogenesis of AIDS and for manipulating immune and inflammatory responses for clinical benefit

  13. T-cell Receptor Excision Circles (TREC) in CD4+ and CD8+ T-cell Subpopulations in Atopic Dermatitis and Psoriasis Show Major Differences in the Emission of Recent Thymic Emigrants

    DEFF Research Database (Denmark)

    Just, Helle; Deleuran, Mette; Vestergaard, Christian

    2008-01-01

    dermatitis showed signs of altered thymus function, as they had a significantly greater variation in TREC content measured over time than healthy controls, especially within the CD8+ T-cell subpopulation. Because both atopic derma nottitis and psoriasis patients have an increased number of T...

  14. T-cells in the cerebrospinal fluid express a similar repertoire of inflammatory chemokine receptors in the absence or presence of CNS inflammation

    DEFF Research Database (Denmark)

    Kivisäkk, P; Trebst, C; Liu, Z

    2002-01-01

    It is believed that chemokines and their receptors are involved in trafficking of T-cells to the central nervous system (CNS). The aim of the current study was to define the expression on cerebrospinal fluid (CSF) T-cells of six chemokine receptors associated with trafficking to sites...... is not sufficient for the trafficking of CD3+T-cells to the CSF. We hypothesize that CXCR3 is the principal inflammatory chemokine receptor involved in intrathecal accumulation of T-cells in MS. Through interactions with its ligands, CXCR3 is proposed to mediate retention of T-cells in the inflamed CNS....

  15. Structure-kinetic relationships--an overlooked parameter in hit-to-lead optimization : a case of cyclopentylamines as chemokine receptor 2 antagonists

    NARCIS (Netherlands)

    Vilums, Maris; Zweemer, Annelien J. M.; Yu, Zhiyi; de Vries, Henk; Hillger, Julia M.; Wapenaar, Hannah; Bollen, Ilse A. E.; Barmare, Farhana; Gross, Raymond; Clemens, Jeremy; Krenitsky, Paul; Brussee, Johannes; Stamos, Dean; Saunders, John; Heitman, Laura H.; IJzerman, Adriaan P.

    2013-01-01

    Preclinical models of inflammatory diseases (e.g., neuropathic pain, rheumatoid arthritis, and multiple sclerosis) have pointed to a critical role of the chemokine receptor 2 (CCR2) and chemokine ligand 2 (CCL2). However, one of the biggest problems of high-affinity inhibitors of CCR2 is their lack

  16. LPS-induced expression of a novel chemokine receptor (L-CCR) in mouse glial cells in vitro and in vivo

    NARCIS (Netherlands)

    Zuurman, MW; Heeroma, J; Brouwer, N; Boddeke, HWGM; Biber, K

    There is increasing evidence that chemokines, specialized regulators of the peripheral immune system, are also involved in the physiology and pathology of the CNS. It is known that glial cells (astrocytes and microglia) express various chemokine receptors like CCR1, -3, -5, and CXCR4. We have

  17. Expression of chemokine receptor CXCR4 in esophageal squamous cell and adenocarcinoma

    International Nuclear Information System (INIS)

    Gockel, Ines; Galle, Peter R; Junginger, Theodor; Moehler, Markus; Schimanski, Carl C; Heinrich, Christian; Wehler, T; Frerichs, K; Drescher, Daniel; Langsdorff, Christian von; Domeyer, Mario; Biesterfeld, Stefan

    2006-01-01

    Prognosis of esophageal cancer is poor despite curative surgery. The chemokine receptor CXCR4 has been proposed to distinctly contribute to tumor growth, dissemination and local immune escape in a limited number of malignancies. The aim of our study was to evaluate the role of CXCR4 in tumor spread of esophageal cancer with a differentiated view of the two predominant histologic types – squamous cell and adenocarcinoma. Esophageal cancer tissue samples were obtained from 102 consecutive patients undergoing esophageal resection for cancer with curative intent. The LSAB+ System was used to detect the protein CXCR4. Tumor samples were classified into two groups based on the homogeneous staining intensity. A cut-off between CXCR4w (= weak expression) and CXCR4s (= strong expression) was set at 1.5 (grouped 0 – 1.5 versus 2.0 – 3). Long-term survival rates were calculated using life tables and the Kaplan-Meier method. Using the Cox's proportional hazards analysis, a model of survival prediction was established. The overall expression rate for CXCR4 in esophageal squamous cell carcinoma was 94.1%. Subdividing these samples, CXCR4w was found in 54.9% and CXCR4s in 45.1%. In adenocarcinoma, an overall expression rate of 89.1% was detected with a weak intensitiy in 71.7% compared to strong staining in 29.3% (p = 0.066 squamous cell versus adenocarcinoma). The Cox's proportional hazards analysis identified the pM-category with a hazard ratio (HR) of 1.860 (95% CI: 1.014–3.414) (p = 0.045), the histologic tumor type (HR: 0.334; 95% CI: 0.180–0.618) (p = 0.0001) and the operative approach (transthoracic > transhiatal esophageal resection) (HR: 0.546; 95% CI: 0.324–0.920) (p = 0.023) as independent factors with a possible influence on the long-term prognosis in patients with esophageal carcinoma, whereas CXCR4 expression was statistically not significant (>0.05). Expression of the chemokine receptor CXCR4 in esophageal cancer is of major relevance in both

  18. Local induction of immunosuppressive CD8+ T cells in the gut-associated lymphoid tissues.

    Science.gov (United States)

    Fleissner, Diana; Hansen, Wiebke; Geffers, Robert; Buer, Jan; Westendorf, Astrid M

    2010-10-20

    In contrast to intestinal CD4(+) regulatory T cells (T(regs)), the generation and function of immunomodulatory intestinal CD8(+) T cells is less well defined. To dissect the immunologic mechanisms of CD8(+) T cell function in the mucosa, reactivity against hemagglutinin (HA) expressed in intestinal epithelial cells of mice bearing a MHC class-I-restricted T-cell-receptor specific for HA was studied. HA-specific CD8(+) T cells were isolated from gut-associated tissues and phenotypically and functionally characterized for the expression of Foxp3(+) and their suppressive capacity. We demonstrate that intestinal HA expression led to peripheral induction of HA-specific CD8(+)Foxp3(+) T cells. Antigen-experienced CD8(+) T cells in this transgenic mouse model suppressed the proliferation of CD8(+) and CD4(+) T cells in vitro. Gene expression analysis of suppressive HA-specific CD8(+) T cells revealed a specific up-regulation of CD103, Nrp1, Tnfrsf9 and Pdcd1, molecules also expressed on CD4(+) T(reg) subsets. Finally, gut-associated dendritic cells were able to induce HA-specific CD8(+)Foxp3(+) T cells. We demonstrate that gut specific antigen presentation is sufficient to induce CD8(+) T(regs)in vivo which may maintain intestinal homeostasis by down-modulating effector functions of T cells.

  19. Local induction of immunosuppressive CD8+ T cells in the gut-associated lymphoid tissues.

    Directory of Open Access Journals (Sweden)

    Diana Fleissner

    Full Text Available BACKGROUND: In contrast to intestinal CD4(+ regulatory T cells (T(regs, the generation and function of immunomodulatory intestinal CD8(+ T cells is less well defined. To dissect the immunologic mechanisms of CD8(+ T cell function in the mucosa, reactivity against hemagglutinin (HA expressed in intestinal epithelial cells of mice bearing a MHC class-I-restricted T-cell-receptor specific for HA was studied. METHODOLOGY AND PRINCIPAL FINDINGS: HA-specific CD8(+ T cells were isolated from gut-associated tissues and phenotypically and functionally characterized for the expression of Foxp3(+ and their suppressive capacity. We demonstrate that intestinal HA expression led to peripheral induction of HA-specific CD8(+Foxp3(+ T cells. Antigen-experienced CD8(+ T cells in this transgenic mouse model suppressed the proliferation of CD8(+ and CD4(+ T cells in vitro. Gene expression analysis of suppressive HA-specific CD8(+ T cells revealed a specific up-regulation of CD103, Nrp1, Tnfrsf9 and Pdcd1, molecules also expressed on CD4(+ T(reg subsets. Finally, gut-associated dendritic cells were able to induce HA-specific CD8(+Foxp3(+ T cells. CONCLUSION AND SIGNIFICANCE: We demonstrate that gut specific antigen presentation is sufficient to induce CD8(+ T(regsin vivo which may maintain intestinal homeostasis by down-modulating effector functions of T cells.

  20. Targeting spare CC chemokine receptor 5 (CCR5) as a principle to inhibit HIV-1 entry.

    Science.gov (United States)

    Jin, Jun; Colin, Philippe; Staropoli, Isabelle; Lima-Fernandes, Evelyne; Ferret, Cécile; Demir, Arzu; Rogée, Sophie; Hartley, Oliver; Randriamampita, Clotilde; Scott, Mark G H; Marullo, Stefano; Sauvonnet, Nathalie; Arenzana-Seisdedos, Fernando; Lagane, Bernard; Brelot, Anne

    2014-07-04

    CCR5 binds the chemokines CCL3, CCL4, and CCL5 and is the major coreceptor for HIV-1 entry into target cells. Chemokines are supposed to form a natural barrier against human immunodeficiency virus, type 1 (HIV-1) infection. However, we showed that their antiviral activity is limited by CCR5 adopting low-chemokine affinity conformations at the cell surface. Here, we investigated whether a pool of CCR5 that is not stabilized by chemokines could represent a target for inhibiting HIV infection. We exploited the characteristics of the chemokine analog PSC-RANTES (N-α-(n-nonanoyl)-des-Ser(1)-[l-thioprolyl(2), l-cyclohexylglycyl(3)]-RANTES(4-68)), which displays potent anti-HIV-1 activity. We show that native chemokines fail to prevent high-affinity binding of PSC-RANTES, analog-mediated calcium release (in desensitization assays), and analog-mediated CCR5 internalization. These results indicate that a pool of spare CCR5 may bind PSC-RANTES but not native chemokines. Improved recognition of CCR5 by PSC-RANTES may explain why the analog promotes higher amounts of β-arrestin 2·CCR5 complexes, thereby increasing CCR5 down-regulation and HIV-1 inhibition. Together, these results highlight that spare CCR5, which might permit HIV-1 to escape from chemokines, should be targeted for efficient viral blockade. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Chemokine receptor Ccr1 drives neutrophil-mediated kidney immunopathology and mortality in invasive candidiasis.

    Science.gov (United States)

    Lionakis, Michail S; Fischer, Brett G; Lim, Jean K; Swamydas, Muthulekha; Wan, Wuzhou; Richard Lee, Chyi-Chia; Cohen, Jeffrey I; Scheinberg, Phillip; Gao, Ji-Liang; Murphy, Philip M

    2012-01-01

    Invasive candidiasis is the 4(th) leading cause of nosocomial bloodstream infection in the US with mortality that exceeds 40% despite administration of antifungal therapy; neutropenia is a major risk factor for poor outcome after invasive candidiasis. In a fatal mouse model of invasive candidiasis that mimics human bloodstream-derived invasive candidiasis, the most highly infected organ is the kidney and neutrophils are the major cellular mediators of host defense; however, factors regulating neutrophil recruitment have not been previously defined. Here we show that mice lacking chemokine receptor Ccr1, which is widely expressed on leukocytes, had selectively impaired accumulation of neutrophils in the kidney limited to the late phase of the time course of the model; surprisingly, this was associated with improved renal function and survival without affecting tissue fungal burden. Consistent with this, neutrophils from wild-type mice in blood and kidney switched from Ccr1(lo) to Ccr1(high) at late time-points post-infection, when Ccr1 ligands were produced at high levels in the kidney and were chemotactic for kidney neutrophils ex vivo. Further, when a 1∶1 mixture of Ccr1(+/+) and Ccr1(-/-) donor neutrophils was adoptively transferred intravenously into Candida-infected Ccr1(+/+) recipient mice, neutrophil trafficking into the kidney was significantly skewed toward Ccr1(+/+) cells. Thus, neutrophil Ccr1 amplifies late renal immunopathology and increases mortality in invasive candidiasis by mediating excessive recruitment of neutrophils from the blood to the target organ.

  2. The prognostic significance of chemokine receptor CXCR3 expression in colorectal carcinoma.

    Science.gov (United States)

    Wu, Zhenqian; Han, Xiaodong; Yan, Jun; Pan, Ye; Gong, Jianfeng; Di, Jianzhong; Cheng, Zhe; Jin, Zhiming; Wang, Zhigang; Zheng, Qi; Wang, Yu

    2012-07-01

    The expression of chemokine receptor CXCR3 has been associated with tumor dissemination and poor prognosis in breast cancer patients. However, it is still unclear whether CXCR3 can be used as an independent molecular marker for predicting the prognosis of colonrectal carcinoma (CRC) patients. In this study, we found that the relative level of CXCR3 mRNA expression in primary colorectal cancer tissues was significantly higher than that in corresponding non-tumor colon tissues. CXCR3 protein expression was also detected in 98 of 112 primary CRC patients. Thus, CXCR3 might play a vital role in the progression of colorectal cancer. By analyzing the correlation between clinicopathological factors of patients and expression of CXCR3 protein, we showed that high level of CXCR3 protein expression was significantly associated with tumor differentiation, tumor size, lymph node metastasis, distant metastasis, and Dukes' classification, but not with other factors of CRC patients including gender, age, tumor location and tumor invasion. Furthermore, patients with high CXCR3 expression showed poorer overall survival than those with low CXCR3 expression. Univariate and multivariate analysis indicated that the status of CXCR3 protein expression might be an independent prognostic marker for CRC patients. Therefore, CXCR3 is an indicator of a poor prognosis and a promising target for cancer therapy in colorectal cancer. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  3. Human Cytomegalovirus Encoded Homologs of Cytokines, Chemokines and their Receptors: Roles in Immunomodulation

    Science.gov (United States)

    McSharry, Brian P.; Avdic, Selmir; Slobedman, Barry

    2012-01-01

    Human cytomegalovirus (HCMV), the largest human herpesvirus, infects a majority of the world’s population. Like all herpesviruses, following primary productive infection, HCMV establishes a life-long latent infection, from which it can reactivate years later to produce new, infectious virus. Despite the presence of a massive and sustained anti-HCMV immune response, productively infected individuals can shed virus for extended periods of time, and once latent infection is established, it is never cleared from the host. It has been proposed that HCMV must therefore encode functions which help to evade immune mediated clearance during productive virus replication and latency. Molecular mimicry is a strategy used by many viruses to subvert and regulate anti-viral immunity and HCMV has hijacked/developed a range of functions that imitate host encoded immunomodulatory proteins. This review will focus on the HCMV encoded homologs of cellular cytokines/chemokines and their receptors, with an emphasis on how these virus encoded homologs may facilitate viral evasion of immune clearance. PMID:23202490

  4. Human Cytomegalovirus Encoded Homologs of Cytokines, Chemokines and their Receptors: Roles in Immunomodulation

    Directory of Open Access Journals (Sweden)

    Brian P. McSharry

    2012-10-01

    Full Text Available Human cytomegalovirus (HCMV, the largest human herpesvirus, infects a majority of the world’s population. Like all herpesviruses, following primary productive infection, HCMV establishes a life-long latent infection, from which it can reactivate years later to produce new, infectious virus. Despite the presence of a massive and sustained anti-HCMV immune response, productively infected individuals can shed virus for extended periods of time, and once latent infection is established, it is never cleared from the host. It has been proposed that HCMV must therefore encode functions which help to evade immune mediated clearance during productive virus replication and latency. Molecular mimicry is a strategy used by many viruses to subvert and regulate anti-viral immunity and HCMV has hijacked/developed a range of functions that imitate host encoded immunomodulatory proteins. This review will focus on the HCMV encoded homologs of cellular cytokines/chemokines and their receptors, with an emphasis on how these virus encoded homologs may facilitate viral evasion of immune clearance.

  5. Role of exonic variation in chemokine receptor genes on AIDS: CCRL2 F167Y association with pneumocystis pneumonia.

    Directory of Open Access Journals (Sweden)

    Ping An

    2011-10-01

    Full Text Available Chromosome 3p21-22 harbors two clusters of chemokine receptor genes, several of which serve as major or minor coreceptors of HIV-1. Although the genetic association of CCR5 and CCR2 variants with HIV-1 pathogenesis is well known, the role of variation in other nearby chemokine receptor genes remain unresolved. We genotyped exonic single nucleotide polymorphisms (SNPs in chemokine receptor genes: CCR3, CCRL2, and CXCR6 (at 3p21 and CCR8 and CX3CR1 (at 3p22, the majority of which were non-synonymous. The individual SNPs were tested for their effects on disease progression and outcomes in five treatment-naïve HIV-1/AIDS natural history cohorts. In addition to the known CCR5 and CCR2 associations, significant associations were identified for CCR3, CCR8, and CCRL2 on progression to AIDS. A multivariate survival analysis pointed to a previously undetected association of a non-conservative amino acid change F167Y in CCRL2 with AIDS progression: 167F is associated with accelerated progression to AIDS (RH = 1.90, P = 0.002, corrected. Further analysis indicated that CCRL2-167F was specifically associated with more rapid development of pneumocystis pneumonia (PCP (RH = 2.84, 95% CI 1.28-6.31 among four major AIDS-defining conditions. Considering the newly defined role of CCRL2 in lung dendritic cell trafficking, this atypical chemokine receptor may affect PCP through immune regulation and inducing inflammation.

  6. CD8+ T cells from a novel T cell receptor transgenic mouse induce liver-stage immunity that can be boosted by blood-stage infection in rodent malaria.

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    Lei Shong Lau

    2014-05-01

    Full Text Available To follow the fate of CD8+ T cells responsive to Plasmodium berghei ANKA (PbA infection, we generated an MHC I-restricted TCR transgenic mouse line against this pathogen. T cells from this line, termed PbT-I T cells, were able to respond to blood-stage infection by PbA and two other rodent malaria species, P. yoelii XNL and P. chabaudi AS. These PbT-I T cells were also able to respond to sporozoites and to protect mice from liver-stage infection. Examination of the requirements for priming after intravenous administration of irradiated sporozoites, an effective vaccination approach, showed that the spleen rather than the liver was the main site of priming and that responses depended on CD8α+ dendritic cells. Importantly, sequential exposure to irradiated sporozoites followed two days later by blood-stage infection led to augmented PbT-I T cell expansion. These findings indicate that PbT-I T cells are a highly versatile tool for studying multiple stages and species of rodent malaria and suggest that cross-stage reactive CD8+ T cells may be utilized in liver-stage vaccine design to enable boosting by blood-stage infections.

  7. Screening of chemokine receptor CCR4 antagonists by capillary zone electrophoresis

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    Zhe Sun

    2011-11-01

    Full Text Available CC chemokine receptor 4 (CCR4 is a kind of G-protein-coupled receptor, which plays a pivotal role in allergic inflammation. The interaction between 2-(2-(4-chloro-phenyl-5-{[(naphthalen-1-ylmethyl-carbamoyl]-methyl}-4-oxo-thiazolidin-3-yl-N-(3-morpholin-4-yl-propyl-acetamide (S009 and the N-terminal extracellular tail (ML40 of CCR4 has been validated to be high affinity by capillary zone electrophoresis (CZE. The S009 is a known CCR4 antagonist. Now, a series of new thiourea derivatives have been synthesized. Compared with positive control S009, they were screened using ML40 as target by CZE to find some new drugs for allergic inflammation diseases. The synthesized compounds XJH-5, XJH-4, XJH-17 and XJH-1 displayed the interaction with ML40, but XJH-9, XJH-10, XJH-11, XJH-12, XJH-13, XJH-14, XJH-3, XJH-8, XJH-6, XJH-7, XJH-15, XJH-16 and XJH-2 did not bind to ML40. Both qualification and quantification characterizations of the binding were determined. The affinity of the four compounds was valued by the binding constant, which was similar with the results of chemotactic experiments. The established CEZ method is capable of sensitive and fast screening for a series of lactam analogs in the drug discovery for allergic inflammation diseases. Keywords: Capillary zone electrophoresis, CCR4 antagonist, 2-(2-(4-chloro-phenyl-5-{[(naphthalen-1-ylmethyl-carbamoyl]-methyl}-4-oxo-thiazolidin-3-yl-N-(3-morpholin-4-yl-propyl-acetamide, Interactions, Structural modification

  8. C-C chemokine receptor-7 mediated endocytosis of antibody cargoes into intact cells

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    Xavier eCharest-Morin

    2013-09-01

    Full Text Available The C-C chemokine receptor-7 (CCR7 is a G protein coupled receptor that has a role in leukocyte homing, but that is also expressed in aggressive tumor cells. Preclinical research supports that CCR7 is a valid target in oncology. In view of the increasing availability of therapeutic monoclonal antibodies that carry cytotoxic cargoes, we studied the feasibility of forcing intact cells to internalize known monoclonal antibodies by exploiting the cycle of endocytosis and recycling triggered by the CCR7 agonist CCL19. Firstly, an anti-CCR7 antibody (CD197; clone 150503 labeled surface recombinant CCR7 expressed in intact HEK 293a cells and the fluorescent antibody was internalized following CCL19 treatment. Secondly, a recombinant myc-tagged CCL19 construction was exploited along the anti-myc monoclonal antibody 4A6. The myc-tagged ligand was produced as a conditioned medium of transfected HEK 293a cells that contained the equivalent of 430 ng/ml of immunoreactive CCL19 (average value, ELISA determination. CCL19-myc, but not authentic CCL19, carried the fluorophore-labeled antibody 4A6 into other recipient cells that expressed recombinant CCR7 (microscopy, cytofluorometry. The immune complexes were apparent in endosomal structures, colocalized well with the small GTPase Rab5 and progressed toward Rab7-positive endosomes. A dominant negative form of Rab5 (GDP-locked inhibited this endocytosis. Further, endosomes in CCL19-myc- or CCL19-stimulated cells were positive for β-arrestin2, but rarely for β-arrestin1. Following treatment with CCL19-myc and the 4A6 antibody, the melanoma cell line A375 that expresses endogenous CCR7 was specifically stained using a secondary peroxidase-conjugated antibody. Agonist-stimulated CCR7 can transport antibody-based cargoes, with possible therapeutic applications in oncology.

  9. Pharmacological inhibition of CXCR2 chemokine receptors modulates paraquat-induced intoxication in rats.

    Science.gov (United States)

    Costa, Kesiane M; Maciel, Izaque S; Kist, Luiza W; Campos, Maria M; Bogo, Maurício R

    2014-01-01

    Paraquat (PQ) is an agrochemical agent commonly used worldwide, which is allied to potential risks of intoxication. This herbicide induces the formation of reactive oxygen species (ROS) that ends up compromising various organs, particularly the lungs and the brain. This study evaluated the deleterious effects of paraquat on the central nervous system (CNS) and peripherally, with special attempts to assess the putative protective effects of the selective CXCR2 receptor antagonist SB225002 on these parameters. PQ-toxicity was induced in male Wistar rats, in a total dose of 50 mg/kg, and control animals received saline solution at the same schedule of administration. Separate groups of animals were treated with the selective CXCR2 antagonist SB225002 (1 or 3 mg/kg), administered 30 min before each paraquat injection. The major changes found in paraquat-treated animals were: decreased body weight and hypothermia, nociception behavior, impairment of locomotor and gait capabilities, enhanced TNF-α and IL-1β expression in the striatum, and cell migration to the lungs and blood. Some of these parameters were reversed when the antagonist SB225002 was administered, including recovery of physiological parameters, decreased nociception, improvement of gait abnormalities, modulation of striatal TNF-α and IL-1β expression, and decrease of neutrophil migration to the lungs and blood. Taken together, our results demonstrate that damage to the central and peripheral systems elicited by paraquat can be prevented by the pharmacological inhibition of CXCR2 chemokine receptors. The experimental evidence presented herein extends the comprehension on the toxicodynamic aspects of paraquat, and opens new avenues to treat intoxication induced by this herbicide.

  10. The role of cholesterol and sphingolipids in chemokine receptor function and HIV-1 envelope glycoprotein-mediated fusion

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    Puri Anu

    2006-12-01

    Full Text Available Abstract Background HIV-1 entry into cells is a multifaceted process involving target cell CD4 and the chemokine receptors, CXCR4 or CCR5. The lipid composition of the host cell plays a significant role in the HIV fusion process as it orchestrates the appropriate disposition of CD4 and co-receptors required for HIV-1 envelope glycoprotein (Env-mediated fusion. The cell membrane is primarily composed of sphingolipids and cholesterol. The effects of lipid modulation on CD4 disposition in the membrane and their role in HIV-1 entry have extensively been studied. To focus on the role of lipid composition on chemokine receptor function, we have by-passed the CD4 requirement for HIV-1 Env-mediated fusion by using a CD4-independent strain of HIV-1 Env. Results Cell fusion mediated by a CD4-independent strain of HIV-1 Env was monitored by observing dye transfer between Env-expressing cells and NIH3T3 cells bearing CXCR4 or CCR5 in the presence or absence of CD4. Chemokine receptor signaling was assessed by monitoring changes in intracellular [Ca2+] mobilization induced by CCR5 or CXCR4 ligand. To modulate target membrane cholesterol or sphingolipids we used Methyl-β-cyclodextrin (MβCD or 1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol (PPMP, respectively. Treatment of the target cells with these agents did not change the levels of CD4 or CXCR4, but reduced levels of CCR5 on the cell surface. Chemokine receptor signalling was inhibited by cholesterol removal but not by treatment with PPMP. HIV-1 Env mediated fusion was inhibited by >50% by cholesterol removal. Overall, PPMP treatment appeared to slow down the rates of CD4-independent HIV-1 Env-mediated Fusion. However, in the case of CXCR4-dependent fusion, the differences between untreated and PPMP-treated cells did not appear to be significant. Conclusion Although modulation of cholesterol and sphingolipids has similar effects on CD4 -dependent HIV-1 Env-mediated fusion, sphingolipid modulation

  11. [Chemokines in ophthalmology].

    Science.gov (United States)

    Bleul, T; Schlunck, G; Reinhard, T; Lapp, T

    2017-12-07

    Chemokines are chemotactically active cytokines, which coordinate the distribution of immune cells within the body and also regulate the migration of leukocytes in malignant and inflammatory processes. Chemokines are a heterogeneous group of short-chain proteins that are divided into different subgroups on the basis of their structure. In addition to the chemokines (ligands) various chemokine receptors also exist. The chemokine system is given its complexity by the high redundancy of ligand-receptor interactions: one single ligand can bind to different receptors and a single receptor can interact with different ligands. In terms of receptors, distinct immune cell types have characteristic receptor expression patterns, which can be used for the immunological characterization of leukocytes. Important basic research is currently leading to a better understanding of the chemokine system. The essential importance of the chemokine system in various diseases of the anterior and posterior eye segments is becoming increasingly apparent. The following synopsis explains the individual clinical aspects as well as the underlying scientific work in the context of "chemokines in ophthalmology".

  12. Reduced thymic maturation but normal effector function of CD8+ T cells in CD8 beta gene-targeted mice

    OpenAIRE

    1994-01-01

    CD8 is a cell surface glycoprotein on major histocompatibility complex class I-restricted T cells. Thymocytes and most peripheral T cells express CD8 as heterodimers of CD8 alpha and CD8 beta. The intestinal intraepithelial lymphocytes (IEL), which have been suggested to be generated extrathymically, express CD8 predominantly as homodimers of CD8 alpha. We have generated CD8 beta gene-targeted mice. CD8 alpha+ T cell population in the thymus and in most peripheral lymphoid organs was reduced ...

  13. Doxycycline and Benznidazole Reduce the Profile of Th1, Th2, and Th17 Chemokines and Chemokine Receptors in Cardiac Tissue from Chronic Trypanosoma cruzi-Infected Dogs

    Science.gov (United States)

    de Paula Costa, Guilherme; Lopes, Laís Roquete; Horta, Aline Luciano; Pontes, Washington Martins; Milanezi, Cristiane M.; Guedes, Paulo Marcos da Mata; de Lima, Wanderson Geraldo; Schulz, Richard

    2016-01-01

    Chemokines (CKs) and chemokine receptors (CKR) promote leukocyte recruitment into cardiac tissue infected by the Trypanosoma cruzi. This study investigated the long-term treatment with subantimicrobial doses of doxycycline (Dox) in association, or not, with benznidazole (Bz) on the expression of CK and CKR in cardiac tissue. Thirty mongrel dogs were infected, or not, with the Berenice-78 strain of T. cruzi and grouped according their treatments: (i) two months after infection, Dox (50 mg/kg) 2x/day for 12 months; (ii) nine months after infection, Bz (3,5 mg/kg) 2x/day for 60 days; (iii) Dox + Bz; and (iv) vehicle. After 14 months of infection, hearts were excised and processed for qPCR analysis of Th1 (CCL2, CCL3, CCL4, CCL5, CXCL9, and CXCL11), Th2 (CCL1, CCL17, CCL24, and CCL26), Th17 (CCL20) CKs, Th1 (CCR5, CCR6, and CXCR3), and Th2/Th17 (CCR3, CCR4, and CCR8) CKR, as well as IL-17. T. cruzi infection increases CCL1, CCL2, CCL4, CCL5, CCL17, CXCL10, and CCR5 expression in the heart. Dox, Bz, or Dox + Bz treatments cause a reversal of CK and CKR and reduce the expression of CCL20, IL-17, CCR6, and CXCR3. Our data reveal an immune modulatory effect of Dox with Bz, during the chronic phase of infection suggesting a promising therapy for cardiac protection. PMID:27688600

  14. CXCL12 chemokine and its receptors as major players in the interactions between immune and nervous systems

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    Alice eGuyon

    2014-03-01

    Full Text Available The chemokine CXCL12/SDF1a has first been described in the immune system where it functions include chemotaxis for lymphocytes and macrophages, migration of hematopoietic cells from fetal liver to bone marrow and the formation of large blood vessels. Among other chemokines, CXCL12 has recently attracted much attention in the brain as it has been shown that it can be produced not only by glial cells but also by neurons. In addition, its receptors CXCR4 and CXCR7, which are belonging to the G-protein coupled receptors family, are abundantly expressed in diverse brain area, CXCR4 being a major co-receptor for human immunodeficiency virus (HIV-1 entry. This chemokine system has been shown to play important roles in brain plasticity processes occurring during development but also in the physiology of the brain in normal and pathological conditions. For example, in neurons, CXCR4 stimulation has been shown regulate the synaptic release of glutamate and GABA. It can also act post-synaptically by activating a G-protein Inward Rectifier K+ (GIRK, a voltage-gated K channel Kv2.1 associated to neuronal survival, and by increasing high voltage activated (HVA Ca2+ currents. In addition, it has been recently evidenced that there are several crosstalks between the CXCL12/CXCR4-7 system and other neurotransmitter systems in the brain (such as GABA, glutamate, opioids ans cannabinoids. Overall, this chemokine system could be one of the key players of the neuro-immune interface that participates in shaping the brain in response to changes in the environment.

  15. Time and Antigen-Stimulation History Influence Memory CD8 T Cell Bystander Responses.

    Science.gov (United States)

    Martin, Matthew D; Shan, Qiang; Xue, Hai-Hui; Badovinac, Vladimir P

    2017-01-01

    Memory CD8 T cells can be activated and induced to produce cytokines and increase stores of cytolytic proteins not only in response to cognate antigen (Ag) but also in response to inflammatory cytokines (bystander responses). Importantly, bystander memory CD8 T cell functions have been shown to be dependent upon memory CD8 T cell fitness, since exhausted CD8 T cells have diminished capacity to respond to inflammatory cues. While it is known that memory CD8 T cell functional abilities, including ability to produce cytokines in response to cognate Ag, change with time after initial Ag encounter and upon multiple Ag stimulations (e.g., primary vs. tertiary CD8 T cell responses), it is unknown if bystander memory CD8 T cell responses are influenced by time or by Ag-exposure history. Here, we examined time and Ag-stimulation history-dependent alterations in virus-specific memory CD8 T cell bystander functions in response to inflammatory cytokines and unrelated bacterial infection. We found that expression of cytokine receptors and ability to produce IFN-γ following heterologous infection or incubation with inflammatory cytokines decreases with time following initial Ag encounter and increases with additional Ag encounters, suggesting that the ability to sense inflammation and respond with bystander cytokine production is dependent on age and Ag-stimulation history of memory CD8 T cells. These data shed further light on the regulation of memory CD8 T cell effector functions and have important implications for the development of vaccines designed to elicit protective memory CD8 T cells.

  16. Chemokines and immunity

    Science.gov (United States)

    Palomino, Diana Carolina Torres; Marti, Luciana Cavalheiro

    2015-01-01

    Chemokines are a large family of small cytokines and generally have low molecular weight ranging from 7 to 15kDa. Chemokines and their receptors are able to control the migration and residence of all immune cells. Some chemokines are considered pro-inflammatory, and their release can be induced during an immune response at a site of infection, while others are considered homeostatic and are involved in controlling of cells migration during tissue development or maintenance. The physiologic importance of this family of mediators is resulting from their specificity − members of the chemokine family induce recruitment of well-defined leukocyte subsets. There are two major chemokine sub-families based upon cysteine residues position: CXC and CC. As a general rule, members of the CXC chemokines are chemotactic for neutrophils, and CC chemokines are chemotactic for monocytes and sub-set of lymphocytes, although there are some exceptions. This review discusses the potential role of chemokines in inflammation focusing on the two best-characterized chemokines: monocyte chemoattractant protein-1, a CC chemokine, and interleukin-8, a member of the CXC chemokine sub-family. PMID:26466066

  17. The role of selected chemokines and their receptors in the pathogenesis and destabilisation of atheromatous plaques in the carotid arteries

    Directory of Open Access Journals (Sweden)

    Maria Konarska-Król

    2015-04-01

    Full Text Available Chemokines are cytokines that act selectively on cells and are capable of inducing selective migration of cells in vitro and in vivo. The term was first coined at the 3rd International Symposium on Chemotactic Cytokines in 1992. The name “chemokine” is a contraction of “chemotactic cytokine,” meaning that these molecules combine features of both cytokines and chemotactic factors. They are a family of low-molecular-mass proteins acting on specific membrane receptors. A cell’s overall sensitivity to chemotaxis depends on the expression profile of chemokine receptors. Atherosclerosis is essentially an excessive inflammatory and proliferative response to the damage of arterial walls. It takes place within the wall and leads to the formation of unstable atherosclerotic plaques. Many chemokines have been studied in terms of their role in the pathogenesis of an atheromatous plaque in the carotid arteries, both in animal models and with the use of human tissue. It  seems that molecules that are the most involved in the formation of atheromas in the carotid arteries include: CCL2, CCL3, CCL4 and CCL5. However, reports are sometimes contradictory, and more research is needed. Finding a marker that could help predict the destabilisation of an atheromatous plaque would be a valuable addition to the standard diagnostic panel of tests used in both the diagnosis and monitoring of vascular pathologies.

  18. A duodenally absorbable CXC chemokine receptor 4 antagonist, KRH-1636, exhibits a potent and selective anti-HIV-1 activity

    Science.gov (United States)

    Ichiyama, Kozi; Yokoyama-Kumakura, Sei; Tanaka, Yuetsu; Tanaka, Reiko; Hirose, Kunitaka; Bannai, Kenji; Edamatsu, Takeo; Yanaka, Mikiro; Niitani, Yoshiaki; Miyano-Kurosaki, Naoko; Takaku, Hiroshi; Koyanagi, Yoshio; Yamamoto, Naoki

    2003-01-01

    A low molecular weight nonpeptide compound, KRH-1636, efficiently blocked replication of various T cell line-tropic (X4) HIV type 1 (HIV-1) in MT-4 cells and peripheral blood mononuclear cells through the inhibition of viral entry and membrane fusion via the CXC chemokine receptor (CXCR)4 coreceptor but not via CC chemokine receptor 5. It also inhibited binding of the CXC chemokine, stromal cell-derived factor 1α, to CXCR4 specifically and subsequent signal transduction. KRH-1636 prevented monoclonal antibodies from binding to CXCR4 without down-modulation of the coreceptor. The inhibitory effect against X4 viral replication by KRH-1636 was clearly reproduced in the human peripheral blood lymphocyte/severe combined immunodeficiency mouse system. Furthermore, this compound was absorbed into the blood after intraduodenal administration as judged by anti-HIV-1 activity and liquid chromatography MS in the plasma. Thus, KRH-1636 seems to be a promising agent for the treatment of HIV-1 infection. PMID:12642669

  19. Increased replication of T-cell-tropic HIV strains and CXC-chemokine receptor-4 induction in T cells treated with macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and RANTES beta-chemokines.

    Science.gov (United States)

    Dolei, A; Biolchini, A; Serra, C; Curreli, S; Gomes, E; Dianzani, F

    1998-01-22

    To study, in T-lymphoid cells, the effects of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and RANTES beta-chemokines on the replication of T-cell-tropic HIV-1 strains, since it has been reported that beta-chemokines interfere with the replication of macrophage-tropic HIV-1 strains, but not T-cell-tropic strains. Freshly phytohaemagglutinin (PHA)-activated peripheral blood lymphocytes (PBL) and cultured PHA-activated T cells from healthy volunteers, as well as the C8166 T-cell line, were treated overnight with beta-chemokines before infection with T-cell-tropic HIV-1 isolates, or human T-lymphotropic virus type IIIB. HIV replication was followed by detecting the production of infectious particles, p24 antigen, and viral sequences. CXC-chemokine receptor (CXCR)-4 expression was followed by detection and quantification of specific transcripts. Pretreatment of T cells with MIP-1alpha, MIP-1beta and RANTES affected T-cell-tropic strains, increased the replication of HIV-1beta and HIV-1RPdT strains dose-dependently, as well as virus absorption and provirus DNA accumulation. These findings were associated with increased accumulation of CXCR-4 transcripts, and mediated by the protein tyrosine kinase signalling. Moreover, beta-chemokines stimulated PBL proliferation. Beta-chemokines increase the adsorption and replication of at least some T-cell-tropic HIV-1 strains, and this is related to stimulated expression of the CXCR-4 coreceptor.

  20. Serum concentrations of chemokines (CCL-5 and CXCL-12), chemokine receptors (CCR-5 and CXCR-4), and IL-6 in patients with posttraumatic stress disorder and avoidant personality disorder.

    Science.gov (United States)

    Ogłodek, Ewa A; Szota, Anna M; Moś, Danuta M; Araszkiewicz, Aleksander; Szromek, Adam R

    2015-12-01

    Posttraumatic stress disorder (PTSD) can be perceived as a psychoneuroimmunological disorder in which cytokines affecting the neurochemical and neuroendocrine functions of the body play an important role. Among cytokines, chemokines participating in activation of the inflammatory response are considered to be crucial. 220 men and women were enrolled in the study. 180 of them constituted the study group. The studied groups consisted of: 60 patients with a diagnosed avoidant personality disorders (APD), 60 patients with a diagnosed APD and with PTSD and of 60 patients with PTSD but without a APD. There were 30 women and 30 men in each group of 60 subjects. The control group consisted of 40 healthy individuals. The plasma levels of chemokines and their receptors (CCL-5, CXCR-5, CXCL-12 and CXCR-4), as well as IL-6, were assessed by ELISA. There was an increase in the CXCL-12 and CCL-5 levels in women and men with the PTSD versus the control group. Also, increased levels of IL-6 and the receptors CXCR-4, CCR-5 were observed in women and men with PTSD. The levels of CXCL-12 and CCL-5 chemokines, as well as CCR-5 and CXCR4 receptors were higher in women than in men. The results of this study indicate a need for assessment of the CCL-5 and CXCL-12 chemokine levels, as they are likely markers of PTSD. Measurement of the concentrations of chemokines, chemokine receptors and IL-6 in women and men with PTSD along with concomittant APD may be useful for early detection of mental disorders. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  1. Increased brain damage after ischaemic stroke in mice lacking the chemokine receptor CCR5

    Science.gov (United States)

    Sorce, S; Bonnefont, J; Julien, S; Marq-Lin, N; Rodriguez, I; Dubois-Dauphin, M; Krause, KH

    2010-01-01

    Background and purpose: The chemokine receptor CCR5 is well known for its function in immune cells; however, it is also expressed in the brain, where its specific role remains to be elucidated. Because genetic factors may influence the risk of developing cerebral ischaemia or affect its clinical outcome, we have analysed the role of CCR5 in experimental stroke. Experimental approach: Permanent cerebral ischaemia was performed by occlusion of the middle cerebral artery in wild-type and CCR5-deficient mice. Locomotor behaviour, infarct size and histochemical alterations were analysed at different time points after occlusion. Key results: The cerebral vasculature was comparable in wild-type and CCR5-deficient mice. However, the size of the infarct and the motor deficits after occlusion were markedly increased in CCR5-deficient mice as compared with wild type. No differences between wild-type and CCR5-deficient mice were elicited by occlusion with respect to the morphology and abundance of astrocytes and microglia. Seven days after occlusion the majority of CCR5-deficient mice displayed neutrophil invasion in the infarct region, which was not observed in wild type. As compared with wild type, the infarct regions of CCR5-deficient mice were characterized by increased neuronal death. Conclusions and implications: Lack of CCR5 increased the severity of brain injury following occlusion of the middle cerebral artery. This is of particular interest with respect to the relatively frequent occurrence of CCR5 deficiency in the human population (1–2% of the Caucasian population) and the advent of CCR5 inhibitors as novel drugs. PMID:20423342

  2. CHEMOKINE RECEPTORS AT DISTINCT DIFFERENTIATION STAGES OF T-HELPERS FROM PERIPHERAL BLOOD

    Directory of Open Access Journals (Sweden)

    I. V. Kudryavtsev

    2016-01-01

    Full Text Available Expression of chemokine receptors (CCR4, CCR6, CXCR3 and CXCR5 on T-helper (Th cells at various levels of differentiation in a group of healthy volunteers (n = 52 was assessed on the basis of CD45RA and CD62L expression, using the eight-color flow cytometry. It was found that the “naive” T helper cells (N with CD45RA+CD62L+ phenotype express CXCR3 (4.94±0.39%, and CXCR5 (3.63±0.25%. About 50% of central memory T helpers (CD45RA–CD62L+, CM were CXCR3 positive, and 43.72±1.27% of CM cells expressed CCR6, whereas CXCR5 and CCR4 levels were about 30%. Furthermore, CXCR3 was expressed by 76.76±0.75% of the CD3+CD4+CD45RA–CD62L– (EM population, and similar values were obtained for CCR6, while the relative abundance of CXCR5+ cells decreased to 13.68±0.50%, and CCR4 levels did not change and accounted for 33.26±1.13% positive cells. Likewise, co-expression of the chemokine receptors was studied for the abovementioned subpopulations of T helper cells. Among the CXCR5– Th, Th1 cells were identified as CXCR3+CCR6–CCR4– (this subset also contained Th9, and CXCR3+CCR6+CCR4– subsets, referred to as Th1/Th17. Th2 were detected on the basis of CCR4 expression in absence of all other chemokine receptors. In addition to the mentioned Th1/Th17 populations, Th 17 cells were found in the subsets of Th17 CXCR3–CCR6+CCR4– and CXCR3–CR6+CCR4+. The latter also contained a Th22 population. Follicular Th cell populations (CXCR5+ consisted of, at least, six different subsets: CXCR3–CCR6–CCR4– (Tfh/Tfh2, CXCR3–CCR6–CCR4+ (Tfh2, CXCR3-CCR6+CCR4–(Tfh17, CXCR3–CCR6+CCR4+ (Tfh17, CXCR3+CCR6–CCR4– (Tfh1 and CXCR3+CCR6+CCR4–(Tfh1/Tfh17. The cells with Th1/Th9 and Th1/Th17 phenotypes dominated among CM (about 13%, whereas their relative abundance within EM increased to 22.37±1.69% and 31.69±1.52%, respectively. The amounts of Th2 were 8.15±0.46% within CM, and only 1.72±0.15% for EM population. For the cells

  3. Comparative analysis of CD8 expressed on mature CD4+ CD8+ T cell clones cultured with IL-4 and that on CD8+ T cell clones: implication for functional significance of CD8 beta

    NARCIS (Netherlands)

    Hori, T.; Paliard, X.; de Waal Malefijt, R.; Ranes, M.; Spits, H.

    1991-01-01

    Interleukin (IL-4) can induce CD8 expression on mature CD4+ T cells. To study this phenomenon in more detail, we characterized CD8 expressed on IL-4-induced CD4+ CD8+ (double positive) T cell clones in comparison with that on CD8+ T cell clones. Using 2ST8-5H7 mAb that detects CD8 beta expression,

  4. Immune Checkpoint Function of CD85j in CD8 T Cell Differentiation and Aging.

    Science.gov (United States)

    Gustafson, Claire E; Qi, Qian; Hutter-Saunders, Jessica; Gupta, Sheena; Jadhav, Rohit; Newell, Evan; Maecker, Holden; Weyand, Cornelia M; Goronzy, Jörg J

    2017-01-01

    Aging is associated with an increased susceptibility to infection and a failure to control latent viruses thought to be driven, at least in part, by alterations in CD8 T cell function. The aging T cell repertoire is characterized by an accumulation of effector CD8 T cells, many of which express the negative regulatory receptor CD85j. To define the biological significance of CD85j expression on CD8 T cells and to address the question whether presence of CD85j in older individuals is beneficial or detrimental for immune function, we examined the specific attributes of CD8 T cells expressing CD85j as well as the functional role of CD85j in antigen-specific CD8 T cell responses during immune aging. Here, we show that CD85j is mainly expressed by terminally differentiated effector (TEMRAs) CD8 T cells, which increase with age, in cytomegalovirus (CMV) infection and in males. CD85j + CMV-specific cells demonstrate clonal expansion. However, TCR diversity is similar between CD85j + and CD85j - compartments, suggesting that CD85j does not directly impact the repertoire of antigen-specific cells. Further phenotypic and functional analyses revealed that CD85j identifies a specific subset of CMV-responsive CD8 T cells that coexpress a marker of senescence (CD57) but retain polyfunctional cytokine production and expression of cytotoxic mediators. Blocking CD85j binding enhanced proliferation of CMV-specific CD8 T cells upon antigen stimulation but did not alter polyfunctional cytokine production. Taken together, these data demonstrate that CD85j characterizes a population of "senescent," but not exhausted antigen-specific effector CD8 T cells and indicates that CD85j is an important checkpoint regulator controlling expansion of virus-specific T cells during aging. Inhibition of CD85j activity may be a mechanism to promote stronger CD8 T cell effector responses during immune aging.

  5. B cell attracting chemokine 1 (CXCL13) and its receptor CXCR5 are expressed in normal and aberrant gut associated lymphoid tissue

    OpenAIRE

    Carlsen, H S; Baekkevold, E S; Johansen, F-E; Haraldsen, G; Brandtzaeg, P

    2002-01-01

    Background and aims: In mice, the B lymphocyte chemoattractant (BLC) CXC chemokine ligand 13 (CXCL13) is sufficient to induce a series of events leading to the formation of organised lymphoid tissue. Its receptor, CXCR5, is required for normal development of secondary lymphoid tissue. However, the human counterpart, B cell attracting chemokine 1 (BCA-1) has only been detected in the stomach and appendix and not in other parts of normal or diseased gut. Hence to elucidate the potential role of...

  6. Chemokines: structure, receptors and functions. A new target for inflammation and asthma therapy?

    Directory of Open Access Journals (Sweden)

    F. A. A. van Acker

    1996-01-01

    Full Text Available Five to 10% of the human population have a disorder of the respiratory tract called ‘asthma’. It has been known as a potentially dangerous disease for over 2000 years, as it was already described by Hippocrates and recognized as a disease entity by Egyptian and Hebrew physicians. At the beginning of this decade, there has been a fundamental change in asthma management. The emphasis has shifted from symptom relief with bronchodilator therapies (e.g. β2-agonists to a much earlier introduction of anti-inflammatory treatment (e.g. corticosteroids. Asthma is now recognized to be a chronic inflammatory disease of the airways, involving various inflammatory cells and their mediators. Although asthma has been the subject of many investigations, the exact role of the different inflammatory cells has not been elucidated completely. Many suggestions have been made and several cells have been implicated in the pathogenesis of asthma, such as the eosinophils, the mast cells, the basophils and the lymphocytes. To date, however, the relative importance of these cells is not completely understood. The cell type predominantly found in the asthmatic lung is the eosinophil and the recruitment of these eosinophils can be seen as a characteristic of asthma. In recent years much attention is given to the role of the newly identified chemokines in asthma pathology. Chemokines are structurally and functionally related 8–10 kDa peptides that are the products of distinct genes clustered on human chromosomes 4 and 17 and can be found at sites of inflammation. They form a superfamily of proinflammatory mediators that promote the recruitment of various kinds of leukocytes and lymphocytes. The chemokine superfamily can be divided into three subgroups based on overall sequence homology. Although the chemokines have highly conserved amino acid sequences, each of the chemokines binds to and induces the chemotaxis of particular classes of white blood cells. Certain

  7. First Experience with Chemokine Receptor CXCR4-Targeted PET Imaging of Patients with Solid Cancers.

    Science.gov (United States)

    Vag, Tibor; Gerngross, Carlos; Herhaus, Peter; Eiber, Matthias; Philipp-Abbrederis, Kathrin; Graner, Frank-Philipp; Ettl, Johannes; Keller, Ulrich; Wester, Hans-Jürgen; Schwaiger, Markus

    2016-05-01

    CXCR4 is a chemokine receptor that is overexpressed in various human cancers and is involved in tumor metastasis. The aim of this proof-of-concept study was to evaluate a novel CXCR4-targeted PET probe in patients with solid cancers with reported in vitro evidence of CXCR4 overexpression and to estimate its potential diagnostic value. Twenty-one patients with histologically proven pancreatic cancer, laryngeal cancer, non-small cell lung cancer, prostate cancer, melanoma, breast cancer, hepatocellular carcinoma, glioblastoma, sarcoma, or cancer of unknown primary underwent PET imaging using the novel CXCR4 nuclear probe (68)Ga-pentixafor. The SUVmax of the liver, spleen, and bone marrow was measured to determine physiologic tracer distribution. For evaluation of tracer accumulation in solid cancers, SUVmax and tumor-to-background (T/B) ratios were determined in a total of 43 malignant lesions, including 8 primary tumors, 3 locally recurrent tumors, and 32 metastases. When available, the SUVmax of malignant lesions was compared with the corresponding SUVmax measured in routine (18)F-FDG PET. Moderate tracer accumulation was detectable in the liver, bone marrow, and spleen, with a mean SUVmax of 3.1, 3.7, and 5.6, respectively. By visual interpretation criteria, 9 of 11 primary and locally recurrent tumors were detectable, exhibiting a mean SUVmax of 4.7 (range, 2.1-10.9) and a mean T/B ratio of 2.9. Twenty of 32 evaluated metastases were visually detectable (mean SUVmax, 4.5 [range, 3.2-13.8]; mean T/B ratio, 2.8). The highest signal was detected in a patient with non-small cell lung cancer (SUVmax, 10.9; T/B ratio, 8.4) and a patient with cancer of unknown primary (SUVmax, 13.8; T/B ratio, 8.1). Compared with (18)F-FDG PET, which was additionally performed in 10 patients, (68)Ga-pentixafor PET had a lower SUVmax in all measured malignant lesions. On the basis of these first observations in a small and heterogeneous patient cohort, the in vitro CXCR4 expression

  8. The chemokine CXCL16 and its receptor, CXCR6, as markers and promoters of inflammation-associated cancers.

    Directory of Open Access Journals (Sweden)

    Merav Darash-Yahana

    2009-08-01

    Full Text Available Clinical observations and mouse models have suggested that inflammation can be pro-tumorigenic. Since chemokines are critical in leukocyte trafficking, we hypothesized that chemokines play essential roles in inflammation-associated cancers. Screening for 37 chemokines in prostate cancer cell lines and xenografts revealed CXCL16, the ligand for the receptor CXCR6, as the most consistently expressed chemokine. Immunohistochemistry and/or immunofluorescence and confocal imaging of 121 human prostate specimens showed that CXCL16 and CXCR6 were co-expressed, both on prostate cancer cells and adjacent T cells. Expression levels of CXCL16 and CXCR6 on cancer cells correlated with poor prognostic features including high-stage and high-grade, and expression also correlated with post-inflammatory changes in the cancer stroma as revealed by loss of alpha-smooth muscle actin. Moreover, CXCL16 enhanced the growth of CXCR6-expressing cancer and primary CD4 T cells. We studied expression of CXCL16 in an additional 461 specimens covering 12 tumor types, and found that CXCL16 was expressed in multiple human cancers associated with inflammation. Our study is the first to describe the expression of CXCL16/CXCR6 on both cancer cells and adjacent T cells in humans, and to demonstrate correlations between CXCL16 and CXCR6 vs. poor both prognostic features and reactive changes in cancer stoma. Taken together, our data suggest that CXCL16 and CXCR6 may mark cancers arising in an inflammatory milieu and mediate pro-tumorigenic effects of inflammation through direct effects on cancer cell growth and by inducing the migration and proliferation of tumor-associated leukocytes.

  9. The expression of chemokine receptors CXCR3 and CXCR4 in predicting postoperative tumour progression in stages I-II colon cancer: a retrospective study.

    Science.gov (United States)

    Du, Changzheng; Yao, Yunfeng; Xue, Weicheng; Zhu, Wei-Guo; Peng, Yifan; Gu, Jin

    2014-01-01

    The prognostic significance of chemokine receptors in stage I/II colon cancer is unclear. We assessed the prognostic value of chemokine receptor CXCR3 and CXCR4 in stage I/II colon cancer. 145 patients with stage I/II colon cancer who underwent curative surgery alone from 2000 to 2007 were investigated. Chemokine receptor expression was assessed by immunohistochemistry. The associations between CXCR3, CXCR4 and clinicopathological variables were analysed using the χ2 test, and the relationships between chemokine receptors and a 5-year disease-free survival were analysed by univariate and multivariate analyses. The high-expression rates of CXCR3 and CXCR4 were 17.9% (26/145) and 38.6% (56/145), respectively. There were no significant associations between the expressions of CXCR3, CXCR4 and clinicopathological factors including gender, age, tumour location, histological differentiation, pathological stage, lymphovascular invasion and pretreatment serum carcinoembryonic antigen (CEA). The 5-year disease-free survival was not significantly different between low-expression groups and high-expression groups of CXCR3 and CXCR4. Multivariate analysis revealed that serum CEA and a number of retrieved lymph nodes, rather than chemokine receptors, were independent prognosticators. CXCR3 and CXCR4 are not independent prognosticators for stage I/II colon cancer after curative surgery.

  10. The effect of combined polymorphisms in chemokines and chemokine receptors on the clinical course of HIV-1 infection in a Brazilian population

    Directory of Open Access Journals (Sweden)

    Valdimara Corrêa Vieira

    2011-06-01

    Full Text Available Polymorphisms in genes that encode chemokines or their receptors can modulate susceptibility to human immunodeficiency virus (HIV infection and disease progression. The objective of this study was to assess the frequency of polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A and their role in the course of HIV infection in a Southern Brazilian population. Clinical data were obtained from 249 patients for an average period of 6.4 years and genotypes were determined by standard polymerase chain reaction (PCR and PCR-restriction fragment length polymorphism. Survival analyses were conducted for three outcomes: CD4+ T-cell counts below 200 cells/µL, acquired immune deficiency syndrome (AIDS or death. The frequency of the polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A were 0.024, 0.113, 0.487 and 0.207, respectively. CCR5-Δ32 was associated with a reduction in the risk for CD4+ T-cell depletion and with an increased risk for death after AIDS diagnosis. CCR2-64I was associated with a reduction in the risk for developing AIDS. SDF1-3'A was also associated with decreased risk for AIDS, but its effect was only evident when CCR2-64I was present as well. These results highlight the possibility of using these markers as indicators for the prognosis of disease progression and provide evidence for the importance of analysing the effects of gene polymorphisms in a combined fashion.

  11. Interleukin 15 is a growth factor for human thymocytes with preferential effect on CD8(+)cells

    DEFF Research Database (Denmark)

    Thulesen, S; Nielsen, M; Petersen, T R

    2000-01-01

    The effects of IL-15, as compared to IL-2, on growth of human thymocytes has been evaluated. Expression of comparable amounts of receptor chains was found on IL-2 and IL-15 cultured thymocytes, as well as comparable receptor signalling. However, IL-15 was superior to IL-2 in promoting CD8...

  12. Structure and function of A41, a vaccinia virus chemokine binding protein.

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    Mohammad W Bahar

    2008-01-01

    Full Text Available The vaccinia virus (VACV A41L gene encodes a secreted 30 kDa glycoprotein that is nonessential for virus replication but affects the host response to infection. The A41 protein shares sequence similarity with another VACV protein that binds CC chemokines (called vCKBP, or viral CC chemokine inhibitor, vCCI, and strains of VACV lacking the A41L gene induced stronger CD8+ T-cell responses than control viruses expressing A41. Using surface plasmon resonance, we screened 39 human and murine chemokines and identified CCL21, CCL25, CCL26 and CCL28 as A41 ligands, with Kds of between 8 nM and 118 nM. Nonetheless, A41 was ineffective at inhibiting chemotaxis induced by these chemokines, indicating it did not block the interaction of these chemokines with their receptors. However the interaction of A41 and chemokines was inhibited in a dose-dependent manner by heparin, suggesting that A41 and heparin bind to overlapping sites on these chemokines. To better understand the mechanism of action of A41 its crystal structure was solved to 1.9 A resolution. The protein has a globular beta sandwich structure similar to that of the poxvirus vCCI family of proteins, but there are notable structural differences, particularly in surface loops and electrostatic charge distribution. Structural modelling suggests that the binding paradigm as defined for the vCCI-chemokine interaction is likely to be conserved between A41 and its chemokine partners. Additionally, sequence analysis of chemokines binding to A41 identified a signature for A41 binding. The biological and structural data suggest that A41 functions by forming moderately strong (nM interactions with certain chemokines, sufficient to interfere with chemokine-glycosaminoglycan interactions at the cell surface (microM-nM and thereby to destroy the chemokine concentration gradient, but not strong enough to disrupt the (pM chemokine-chemokine receptor interactions.

  13. Bcl-2 Allows Effector and Memory CD8+ T Cells To Tolerate Higher Expression of Bim

    Science.gov (United States)

    Kurtulus, Sema; Tripathi, Pulak; Moreno-Fernandez, Maria E.; Sholl, Allyson; Katz, Jonathan D.; Grimes, H. Leighton; Hildeman, David A.

    2014-01-01

    As acute infections resolve, most effector CD8+ T cells die, whereas some persist and become memory T cells. Recent work showed that subsets of effector CD8+ T cells, identified by reciprocal expression of killer cell lectin-like receptor G1 (KLRG1) and CD127, have different lifespans. Similar to previous reports, we found that effector CD8+ T cells reported to have a longer lifespan (i.e., KLRG1lowCD127high) have increased levels of Bcl-2 compared with their shorter-lived KLRG1highCD127low counterparts. Surprisingly, we found that these effector KLRG1lowCD127high CD8+ T cells also had increased levels of Bim compared with KLRG1highCD127low cells. Similar effects were observed in memory cells, in which CD8+ central memory T cells expressed higher levels of Bim and Bcl-2 than did CD8+ effector memory T cells. Using both pharmacologic and genetic approaches, we found that survival of both subsets of effector and memory CD8+ T cells required Bcl-2 to combat the proapoptotic activity of Bim. Interestingly, inhibition or absence of Bcl-2 led to significantly decreased expression of Bim in surviving effector and memory T cells. In addition, manipulation of Bcl-2 levels by IL-7 or IL-15 also affected expression of Bim in effector CD8+ T cells. Finally, we found that Bim levels were significantly increased in effector CD8+ T cells lacking Bax and Bak. Together, these data indicate that cells having the highest levels of Bim are selected against during contraction of the response and that Bcl-2 determines the level of Bim that effector and memory T cells can tolerate. PMID:21451108

  14. CD8(+)NKT-like cells regulate the immune response by killing antigen-bearing DCs.

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-09-15

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8(+)NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8(+)NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8(+)NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8(+)NKT-like cell development is normal in CD1d(-/-) mice, which suggests that CD8(+)NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8(+)NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8(+)NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8(+)NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens.

  15. CD8+NKT-like cells regulate the immune response by killing antigen-bearing DCs

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-01-01

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8+NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8+NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8+NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8+NKT-like cell development is normal in CD1d−/− mice, which suggests that CD8+NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8+NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8+NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8+NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens. PMID:26369936

  16. Effector and memory CD8+ T cells as seen in immunity to malaria.

    Science.gov (United States)

    Morrot, Alexandre; Zavala, Fidel

    2004-10-01

    Transgenic (Tg) mice carrying a T-cell receptor (TCR) specific for a CD8(+) T-cell epitope expressed in pre-erythrocytic stages of Plasmodium yoelii has proven to be a valuable tool to advance our understanding of this anti-parasite T-cell response, as it occurs in vivo. The visualization of CD8(+) T cells in vivo and ex vivo greatly facilitated research aimed at characterizing basic features of this T-cell response such as the kinetics of differentiation and proliferation and the in vivo antigen presentation. Importantly, this research unveiled the existence of early self-regulatory mechanisms controlling the magnitude of the CD8(+) T-cell response and also identified CD4(+) T cells as critical elements in the development of memory populations. This review discusses our recent research using Tg mice and highlights our progress in understanding the CD8(+) T-cell-mediated immunity against malaria liver stages.

  17. Molecular Mechanism of Action for Allosteric Modulators and Agonists in CC-chemokine Receptor 5 (CCR5)

    DEFF Research Database (Denmark)

    Karlshøj, Stefanie; Amarandi, Roxana Maria; Larsen, Olav

    2016-01-01

    The small molecule metal-ion chelators bipyridine and terpyridine complexed with Zn(2+) (ZnBip and ZnTerp) act as CCR5 agonists and strong positive allosteric modulators of CCL3-binding to CCR5, weak modulators of CCL4-binding, and as competitors for CCL5-binding. Here we describe their binding...... site using computational modeling, binding and functional studies on WT and mutated CCR5. The metal-ion Zn(2+) is anchored to the chemokine receptor-conserved E283(VII:06/7.39) Both chelators interact with aromatic residues in the transmembrane receptor domain. The additional pyridine ring of Zn....../1.39), W86(II:20/2.60) and F109(III:09/3.33) The small molecules and CCL3 approach this interface from opposite directions with some residues being mutually exploited. This study provides new insight into the molecular mechanism of CCR5 activation and paves the way for future allosteric drugs for chemokine...

  18. Chemokine Receptor-5Δ32 Mutation is No Risk Factor for Ischemic-Type Biliary Lesion in Liver Transplantation

    Directory of Open Access Journals (Sweden)

    Christoph Heidenhain

    2009-01-01

    Full Text Available It has been shown that certain chemokine receptor polymorphisms may correspond to certain complications after organ transplantation. Ischemic-type biliary lesion (ITBL encounters for major morbidity and mortality in liver transplant recipients. So far, the exact cause for ITBL remains unclear. Certain risk factors for the development of ITBL like donor age and cold ischemic time are well described. In a previous study, a 32-nucleotide deletion of the chemokine receptor-5Δ32 (CCR-5Δ32 was strongly associated with the incidence of ITBL in adult liver transplantation. This study re-evaluates the association of CCR-5Δ32 gene polymorphism and the incidence of ITBL. 169 patients were included into this retrospective analysis. 134 patients were homozygous for wild-type CCR-5, 33 patients heterozygous, and 2 patients were homozygous for CCR-5Δ32 mutation. There were no major differences in donor or recipients demographics. No association was found between CCR-5Δ32 mutation and the development of ITBL. We conclude that CCR-5Δ32 is no risk factor for the development of ITBL in our patient cohort.

  19. The Serum Concentrations of Chemokine CXCL12 and Its Specific Receptor CXCR4 in Patients with Esophageal Cancer

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    Marta Łukaszewicz-Zając

    2016-01-01

    Full Text Available Objectives. Recent investigations have suggested that upregulated levels of inflammatory biomarkers, such as chemokines, may be associated with development of many malignancies, including esophageal cancer (EC. Based on our knowledge, this study is the first to assess the serum concentration of chemokine CXCL12 and its specific receptor CXCR4 in the diagnosis of EC patients. Material and Methods. The present study included 79 subjects: 49 patients with EC and 30 healthy volunteers. The serum concentrations of CXCL12 and CXCR4 and classical tumor markers such as carcinoembryonal antigen (CEA and squamous cell cancer antigen (SCC-Ag were measured using immunoenzyme assays, while C-reactive protein (CRP levels were assessed by immunoturbidimetric method. Moreover, diagnostic criteria of all proteins tested and the survival of EC patients were assessed. Results. The serum concentrations of CXCL12 were significantly higher, while those of its receptor CXCR4 were significantly lower in EC patients compared to healthy controls. The diagnostic sensitivity, negative predictive value, and accuracy of CXCR4 were the highest among all analyzed proteins and increased for combined analysis with classical tumor markers and CRP levels. Conclusion. Our findings suggest that serum CXCR4 may improve the diagnosis of EC patients, especially in combination with classical tumor markers.

  20. Investigation of C-C chemokine receptor type 4 (ccr4 gene polymorphism in patients with Gestational Trophoblastic diseases (GTD

    Directory of Open Access Journals (Sweden)

    S Naeimi

    2011-08-01

    Full Text Available Introduction & Objective: Gestational trophoblastic disease (GTD consists of a spectrum of disorders that are characterized by an abnormal proliferation of trophoblastic tissue, following an abnormal fertilization. CCR4 is one chemo-attractant receptors preferentially expressed on Th2 cells, and therefore, is likely to participate in the recruitment of antigen-specific Th2 cells to sites of allergen exposure. Variations in CCR4 have been reported. In this study we intended to investigate the relationship between polymorphism of this particular gene at the site of 1014 C/T and GTD. Materials & Methods: In the present study, the polymorphisms of the CCR4 gene at the sites of 1014 C/T was investigated in 100 patients at in 2010 with proved GTD and 120 age-sex matched healthy individuals. Polymorphysm of CC chemokine 4 were investigated in these two groups by PCR-RFLP.These two groups were compared in respect their genotypes and alleles. Results: Frequency of genotype TT, CT, CC patients were 34%, 62% and 4% while the frequency of the control group, were 46.7%, 35.8% and 17.5% respectively. A significant difference was seen in genotype prevalence of 1014 C/T in ccr4 gene in the two mentioned groups (P0.05(. Conclusion: Regarding the relationship between The C-C chemokine receptor type 4 and gestational trophoblastic disease (GTD, it might be possible to use this gene as a prognostic marker in identifying the susceptible patients.

  1. Glutamine Supplementation Attenuates Expressions of Adhesion Molecules and Chemokine Receptors on T Cells in a Murine Model of Acute Colitis

    Directory of Open Access Journals (Sweden)

    Yu-Chen Hou

    2014-01-01

    Full Text Available Background. Migration of T cells into the colon plays a major role in the pathogenesis in inflammatory bowel disease. This study investigated the effects of glutamine (Gln supplementation on chemokine receptors and adhesion molecules expressed by T cells in mice with dextran sulfate sodium- (DSS- induced colitis. Methods. C57BL/6 mice were fed either a standard diet or a Gln diet replacing 25% of the total nitrogen. After being fed the diets for 5 days, half of the mice from both groups were given 1.5% DSS in drinking water to induce colitis. Mice were killed after 5 days of DSS exposure. Results. DSS colitis resulted in higher expression levels of P-selectin glycoprotein ligand- (PSGL- 1, leukocyte function-associated antigen- (LFA- 1, and C-C chemokine receptor type 9 (CCR9 by T helper (Th and cytotoxic T (Tc cells, and mRNA levels of endothelial adhesion molecules in colons were upregulated. Gln supplementation decreased expressions of PSGL-1, LFA-1, and CCR9 by Th cells. Colonic gene expressions of endothelial adhesion molecules were also lower in Gln-colitis mice. Histological finding showed that colon infiltrating Th cells were less in the DSS group with Gln administration. Conclusions. Gln supplementation may ameliorate the inflammation of colitis possibly via suppression of T cell migration.

  2. Oligoclonal CD8+ T cells play a critical role in the development of hypertension.

    Science.gov (United States)

    Trott, Daniel W; Thabet, Salim R; Kirabo, Annet; Saleh, Mohamed A; Itani, Hana; Norlander, Allison E; Wu, Jing; Goldstein, Anna; Arendshorst, William J; Madhur, Meena S; Chen, Wei; Li, Chung-I; Shyr, Yu; Harrison, David G

    2014-11-01

    Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the genesis of hypertension. We sought to determine the T-cell subtypes that contribute to hypertension and renal inflammation in angiotensin II-induced hypertension. Using T-cell receptor spectratyping to examine T-cell receptor usage, we demonstrated that CD8(+) cells, but not CD4(+) cells, in the kidney exhibited altered T-cell receptor transcript lengths in Vβ3, 8.1, and 17 families in response to angiotensin II-induced hypertension. Clonality was not observed in other organs. The hypertension caused by angiotensin II in CD4(-/-) and MHCII(-/-) mice was similar to that observed in wild-type mice, whereas CD8(-/-) mice and OT1xRAG-1(-/-) mice, which have only 1 T-cell receptor, exhibited a blunted hypertensive response to angiotensin II. Adoptive transfer of pan T cells and CD8(+) T cells but not CD4(+)/CD25(-) cells conferred hypertension to RAG-1(-/-) mice. In contrast, transfer of CD4(+)/CD25(+) cells to wild-type mice receiving angiotensin II decreased blood pressure. Mice treated with angiotensin II exhibited increased numbers of kidney CD4(+) and CD8(+) T cells. In response to a sodium/volume challenge, wild-type and CD4(-/-) mice infused with angiotensin II retained water and sodium, whereas CD8(-/-) mice did not. CD8(-/-) mice were also protected against angiotensin-induced endothelial dysfunction and vascular remodeling in the kidney. These data suggest that in the development of hypertension, an oligoclonal population of CD8(+) cells accumulates in the kidney and likely contributes to hypertension by contributing to sodium and volume retention and vascular rarefaction. © 2014 American Heart Association, Inc.

  3. DNGR-1 is dispensable for CD8+ T-cell priming during respiratory syncytial virus infection.

    Science.gov (United States)

    Durant, Lydia R; Pereira, Catherine; Boakye, Aime; Makris, Spyridon; Kausar, Fahima; Goritzka, Michelle; Johansson, Cecilia

    2014-08-01

    During respiratory syncytial virus (RSV) infection CD8(+) T cells both assist in viral clearance and contribute to immunopathology. CD8(+) T cells recognize viral peptides presented by dendritic cells (DCs), which can directly present viral antigens when infected or, alternatively, "cross-present" antigens after endocytosis of dead or dying infected cells. Mouse CD8α(+) and CD103(+) DCs excel at cross-presentation, in part because they express the receptor DNGR-1 that detects dead cells by binding to exposed F-actin and routes internalized cell debris into the cross-presentation pathway. As RSV causes death in infected epithelial cells, we tested whether cross-presentation via DNGR-1 is necessary for CD8(+) T-cell responses to the virus. DNGR-1-deficient or wild-type mice were intranasally inoculated with RSV and the magnitude of RSV-specific CD8(+) T-cell induction was measured. We found that during live RSV infection, cross-presentation via DNGR-1 did not have a major role in the generation of RSV-specific CD8(+) T-cell responses. However, after intranasal immunization with dead cells infected with RSV, a dependence on DNGR-1 for RSV-specific CD8(+) T-cell responses was observed, confirming the ascribed role of the receptor. Thus, direct presentation by DCs may be the major pathway initiating CD8(+) T-cell responses to RSV, while DNGR-1-dependent cross-presentation has no detectable role. © 2014 The Authors. European Journal of Immunology published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Chemokine Receptors CXCR3 and CCR6 and Their Ligands in the Liver and Blood of Patients with Chronic Hepatitis C.

    Science.gov (United States)

    Arsent'eva, N A; Semenov, A V; Lyubimova, N E; Ostankov, Yu V; Elezo, D S; Kudryavtsev, I V; Basina, V V; Esaulenko, E V; Kozlov, K V; Zhdanov, K V; Totolyan, A A

    2015-12-01

    We performed a comprehensive analysis of CCR6 and CXCR3 chemokine receptors and their ligands CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, and CXCL11/ITAC in the liver and blood of patients with chronic hepatitis C at different stages of the disease. TaqMan PCR was used to determine mRNA gene expression of chemokines and their receptors in liver specimens, xMAP multiplex analysis was performed to estimate the concentration of chemokines in blood plasma, and fl ow cytofluorometry was used to evaluate CCR6 and CXCR3 expression on peripheral blood lymphocyte populations. In the liver of patients with hepatitis C, mRNA expression of CXCL10, CCR6, and CXCR3 genes increases with fibrosis progression in the liver tissue. In the plasma, concentrations of all studied chemokines increased depending on the stage of liver fibrosis, CCR6 and CXCR3 expression was changed in various lymphocyte populations. Thus, chemokines are involved in the immunopathogenesis and fibrogenesis in chronic viral hepatitis C. The results suggest using these chemokines in the diagnosis and prognosis of the disease.

  5. A novel inflammatory pathway involved in leukocyte recruitment: role for the kinin B1 receptor and the chemokine CXCL5

    Science.gov (United States)

    Duchene, Johan; Lecomte, Florence; Ahmed, Saleh; Cayla, Cecile; Pesquero, Joao; Bader, Michael; Perretti, Mauro; Ahluwalia, Amrita

    2013-01-01

    The kinin B1 receptor is an inducible receptor not normally expressed but induced by inflammatory stimuli and plays a major role in neutrophil recruitment, particularly in response to the cytokine interleukin-1β (IL-1β). However, the exact mechanism involved in this response is unclear. The aim of this study was to dissect the molecular mechanism involved, in particular to determine whether specific ELR-CXCL chemokines (specific neutrophil chemoattractants) played a role. Using intravital microscopy, we demonstrated that IL-1 β induced leukocyte rolling, adherence and emigration in mesenteric venules of wild type (WT) mice, associated with an increase of B1 receptor mRNA expression, was substantially attenuated (>80%) in B1 receptor knockout mice (B1KO). This effect in B1KO mice was correlated with a selective down regulation of IL-1β-induced CXCL5 mRNA and protein expression compared to WT mice. Furthermore a selective neutralizing CXCL5 antibody caused profound suppression of leukocyte emigration in IL-1β treated WT mice. Finally, treatment of human endothelial cells with IL-1β enhanced mRNA expression of B1 receptor and the human CXCL5 homologues (hCXCL5 and hCXCL6). This response was suppressed by ~50% when cells were pretreated with the B1 receptor antagonist des-Arg9[Leu]8BK whilst treatment with des-Arg9-BK, the B1 receptor agonist, caused a concentration-dependent increase in hCXCL5 and hCXCL6 mRNA expression. This study unveils a pro-inflammatory pathway centred on kinin B1 receptor activation of CXCL5 leading to leukocyte trafficking, and highlights the B1 receptor as a potential target in the therapeutics of inflammatory disease. PMID:17878384

  6. CD8+ T cells in inflammatory demyelinating disease

    DEFF Research Database (Denmark)

    Weiss, Hanne A; Millward, Jason M; Owens, Trevor

    2007-01-01

    We review the contribution made by CD8+ T cells to inflammation in the central nervous system (CNS) in Multiple Sclerosis (MS), and discuss their role in the animal model Experimental Autoimmune Encephalomyelitis (EAE). We show that the inflammatory cytokines interferon-gamma and interleukin-17...... are differentially regulated in CNS-infiltrating CD4+ and CD8+ T cells in EAE, and that CD8+ T cells regulate disease. In MS, CD8+ T cells appear to play a role in promotion of disease, so cytokine regulation is likely different in CD8+ T cells in MS and EAE...

  7. Overview of the Mechanisms that May Contribute to the Non-Redundant Activities of Interferon-Inducible CXC Chemokine Receptor 3 Ligands

    Directory of Open Access Journals (Sweden)

    Mieke Metzemaekers

    2018-01-01

    Full Text Available The inflammatory chemokines CXCL9, CXCL10, and CXCL11 are predominantly induced by interferon (IFN-γ and share an exclusive chemokine receptor named CXC chemokine receptor 3 (CXCR3. With a prototype function of directing temporal and spatial migration of activated T cells and natural killer cells, and inhibitory effects on angiogenesis, these CXCR3 ligands have been implicated in infection, acute inflammation, autoinflammation and autoimmunity, as well as in cancer. Intense former research efforts led to recent and ongoing clinical trials using CXCR3 and CXCR3 ligand targeting molecules. Scientific evidence has claimed mutual redundancy, ligand dominance, collaboration or even antagonism, depending on the (pathophysiological context. Most research on their in vivo activity, however, illustrates that CXCL9, CXCL10, and CXCL11 each contribute to the activation and trafficking of CXCR3 expressing cells in a non-redundant manner. When looking into detail, one can unravel a multistep machinery behind final CXCR3 ligand functions. Not only can specific cell types secrete individual CXCR3 interacting chemokines in response to certain stimuli, but also the receptor and glycosaminoglycan interactions, major associated intracellular pathways and susceptibility to processing by particular enzymes, among others, seem ligand-specific. Here, we overview major aspects of the molecular properties and regulatory mechanisms of IFN-induced CXCR3 ligands, and propose that their in vivo non-redundancy is a reflection of the unprecedented degree of versatility that seems inherent to the IFN-related CXCR3 chemokine system.

  8. Targeting CD8+ T-cell tolerance for cancer immunotherapy.

    Science.gov (United States)

    Jackson, Stephanie R; Yuan, Jinyun; Teague, Ryan M

    2014-01-01

    In the final issue of Science in 2013, the American Association of Science recognized progress in the field of cancer immunotherapy as the 'Breakthrough of the Year.' The achievements were actually twofold, owing to the early success of genetically engineered chimeric antigen receptors (CAR) and to the mounting clinical triumphs achieved with checkpoint blockade antibodies. While fundamentally very different, the common thread of these independent strategies is the ability to prevent or overcome mechanisms of CD8(+) T-cell tolerance for improved tumor immunity. Here we discuss how circumventing T-cell tolerance has provided experimental insights that have guided the field of clinical cancer immunotherapy to a place where real breakthroughs can finally be claimed.

  9. CD4+/CD8+ double-positive T cells

    DEFF Research Database (Denmark)

    Overgaard, Nana H; Jung, Ji-Won; Steptoe, Raymond J

    2015-01-01

    CD4(+)/CD8(+) DP thymocytes are a well-described T cell developmental stage within the thymus. However, once differentiated, the CD4(+) lineage or the CD8(+) lineage is generally considered to be fixed. Nevertheless, mature CD4(+)/CD8(+) DP T cells have been described in the blood and peripheral...... cells, CD4(+)/CD8(+) T cell populations, outside of the thymus, have recently been described to express concurrently ThPOK and Runx3. Considerable heterogeneity exists within the CD4(+)/CD8(+) DP T cell pool, and the function of CD4(+)/CD8(+) T cell populations remains controversial, with conflicting...... reports describing cytotoxic or suppressive roles for these cells. In this review, we describe how transcriptional regulation, lineage of origin, heterogeneity of CD4 and CD8 expression, age, species, and specific disease settings influence the functionality of this rarely studied T cell population....

  10. Herpes simplex virus-1 evasion of CD8+ T cell accumulation contributes to viral encephalitis.

    Science.gov (United States)

    Koyanagi, Naoto; Imai, Takahiko; Shindo, Keiko; Sato, Ayuko; Fujii, Wataru; Ichinohe, Takeshi; Takemura, Naoki; Kakuta, Shigeru; Uematsu, Satoshi; Kiyono, Hiroshi; Maruzuru, Yuhei; Arii, Jun; Kato, Akihisa; Kawaguchi, Yasushi

    2017-10-02

    Herpes simplex virus-1 (HSV-1) is the most common cause of sporadic viral encephalitis, which can be lethal or result in severe neurological defects even with antiviral therapy. While HSV-1 causes encephalitis in spite of HSV-1-specific humoral and cellular immunity, the mechanism by which HSV-1 evades the immune system in the central nervous system (CNS) remains unknown. Here we describe a strategy by which HSV-1 avoids immune targeting in the CNS. The HSV-1 UL13 kinase promotes evasion of HSV-1-specific CD8+ T cell accumulation in infection sites by downregulating expression of the CD8+ T cell attractant chemokine CXCL9 in the CNS of infected mice, leading to increased HSV-1 mortality due to encephalitis. Direct injection of CXCL9 into the CNS infection site enhanced HSV-1-specific CD8+ T cell accumulation, leading to marked improvements in the survival of infected mice. This previously uncharacterized strategy for HSV-1 evasion of CD8+ T cell accumulation in the CNS has important implications for understanding the pathogenesis and clinical treatment of HSV-1 encephalitis.

  11. Cognate antigen stimulation generates potent CD8+ inflammatory effector T cells.

    Directory of Open Access Journals (Sweden)

    Hsueh-Cheng eSung

    2013-12-01

    Full Text Available Inflammatory reactions are believed to be triggered by innate signals and have a major protective role by recruiting innate immunity cells, favoring lymphocyte activation and differentiation, and thus contributing to the sequestration and elimination of the injurious stimuli. Although certain lymphocyte types such as TH17 cells co-participate in inflammatory reactions, their generation from the naïve pool requires the pre-existence of an inflammatory milieu. In this context, inflammation is always regarded as beginning with an innate response that may be eventually perpetuated and amplified by certain lymphocyte types. In contrast, we here show that even in sterile immunizations or in MyD88 deficient mice, CD8 T cells produce a burst of pro-inflammatory cytokines and chemokines. These functions follow opposite rules to the classic CD8 effector functions since they are generated prior to cell expansion and decline before antigen elimination. As few as 56 CD8+ inflammatory effector cells in a lymph node can mobilize 107 cells in 24h, including lymphocytes, natural killer cells and several accessory cell types involved in inflammatory reactions. Thus, although inflammation modulates cognate responses, CD8 cognate responses also initiate local inflammatory reactions.

  12. Characterization of chemokine receptor utilization of viruses in the latent reservoir for human immunodeficiency virus type 1.

    Science.gov (United States)

    Pierson, T; Hoffman, T L; Blankson, J; Finzi, D; Chadwick, K; Margolick, J B; Buck, C; Siliciano, J D; Doms, R W; Siliciano, R F

    2000-09-01

    Latently infected resting CD4(+) T cells provide a long-term reservoir for human immunodeficiency virus type 1 (HIV-1) and are likely to represent the major barrier to virus eradication in patients on combination antiretroviral therapy. The mechanisms by which viruses enter the latent reservoir and the nature of the chemokine receptors involved have not been determined. To evaluate the phenotype of the virus in this compartment with respect to chemokine receptor utilization, full-length HIV-1 env genes were cloned from latently infected cells and assayed functionally. We demonstrate that the majority of the viruses in the latent reservoir utilize CCR5 during entry, although utilization of several other receptors, including CXCR4, was observed. No alternative coreceptors were shown to be involved in a systematic fashion. Although R5 viruses are present in the latent reservoir, CCR5 was not expressed at high levels on resting CD4(+) T cells. To understand the mechanism by which R5 viruses enter latent reservoir, the ability of an R5 virus, HIV-1 Ba-L, to infect highly purified resting CD4(+) T lymphocytes from uninfected donors was evaluated. Entry of Ba-L could be observed when virus was applied at a multiplicity approaching 1. However, infection was limited to a subset of cells expressing low levels of CCR5 and markers of immunologic memory. Naive cells could not be infected by an R5 virus even when challenged with a large inoculum. Direct cell fractionation studies showed that latent virus is present predominantly in resting memory cells but also at lower levels in resting naive cells. Taken together, these findings provide support for the hypothesis that the direct infection of naive T cells is not the major mechanism by which the latent infection of resting T cells is established.

  13. Murine macrophage response from peritoneal cavity requires signals mediated by chemokine receptor CCR-2 during Staphylococcus aureus infection.

    Science.gov (United States)

    Nandi, Ajeya; Bishayi, Biswadev

    2016-02-01

    C-C chemokine receptor-2 (CCR-2) is a cognate receptor for monocyte chemotactic protein-1 (MCP-1), and recent studies revealed that MCP-1-CCR-2 signaling is involved in several inflammatory diseases characterized by macrophage infiltration. Currently, there is no study on the involvement of CCR-2 in the killing of S. aureus by macrophages of Swiss albino mice, and its substantial role in host defense against S. aureus infection in murine macrophages is still unclear. Therefore, the present study was aimed to investigate the functional and interactive role of CCR-2 and MCP-1 in regulating peritoneal macrophage responses with respect to acute S. aureus infection. We found that phagocytosis of S. aureus can serve as an important stimulus for MCP-1 production by peritoneal macrophages, which is dependent directly or indirectly on cytokines, reactive oxygen species and nitric oxide. Neutralization of CCR-2 in macrophages leads to increased production of IL-10 and decreased production of IFN-γ and IL-6. In CCR-2 blocked macrophages, pretreatment with specific blocker of NF-κB or p38-MAPK causes elevation in MCP-1 level and subsequent downregulation of CCR-2 itself. We speculate that CCR-2 is involved in S. aureus-induced MCP-1 production via NF-κB or p38-MAPK signaling. We also hypothesized that unnaturally high level of MCP-1 that build up upon CCR-2 neutralization might allow promiscuous binding to one or more other chemokine receptors, a situation that would not occur in CCR-2 non-neutralized condition. This may be the plausible explanation for such observed Th-2 response in CCR-2 blocked macrophages infected with S. aureus in the present study.

  14. Characterization of Chemokine Receptor Utilization of Viruses in the Latent Reservoir for Human Immunodeficiency Virus Type 1

    Science.gov (United States)

    Pierson, Theodore; Hoffman, Trevor L.; Blankson, Joel; Finzi, Diana; Chadwick, Karen; Margolick, Joseph B.; Buck, Christopher; Siliciano, Janet D.; Doms, Robert W.; Siliciano, Robert F.

    2000-01-01

    Latently infected resting CD4+ T cells provide a long-term reservoir for human immunodeficiency virus type 1 (HIV-1) and are likely to represent the major barrier to virus eradication in patients on combination antiretroviral therapy. The mechanisms by which viruses enter the latent reservoir and the nature of the chemokine receptors involved have not been determined. To evaluate the phenotype of the virus in this compartment with respect to chemokine receptor utilization, full-length HIV-1 env genes were cloned from latently infected cells and assayed functionally. We demonstrate that the majority of the viruses in the latent reservoir utilize CCR5 during entry, although utilization of several other receptors, including CXCR4, was observed. No alternative coreceptors were shown to be involved in a systematic fashion. Although R5 viruses are present in the latent reservoir, CCR5 was not expressed at high levels on resting CD4+ T cells. To understand the mechanism by which R5 viruses enter latent reservoir, the ability of an R5 virus, HIV-1 Ba-L, to infect highly purified resting CD4+ T lymphocytes from uninfected donors was evaluated. Entry of Ba-L could be observed when virus was applied at a multiplicity approaching 1. However, infection was limited to a subset of cells expressing low levels of CCR5 and markers of immunologic memory. Naive cells could not be infected by an R5 virus even when challenged with a large inoculum. Direct cell fractionation studies showed that latent virus is present predominantly in resting memory cells but also at lower levels in resting naive cells. Taken together, these findings provide support for the hypothesis that the direct infection of naive T cells is not the major mechanism by which the latent infection of resting T cells is established. PMID:10933689

  15. Accelerated aging in HIV/AIDS: novel biomarkers of senescent human CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Jennifer P Chou

    Full Text Available Clinical evaluation of immune reconstitution and health status during HIV-1 infection and anti-retroviral therapy (ART is largely based on CD4+ T cell counts and viral load, measures that fail to take into account the CD8+ T cell subset, known to show features of accelerated aging in HIV disease. Here, we compare adenosine deaminase (ADA, glucose uptake receptor 1 (GLUT1, and leucine-rich repeat neuronal 3 (LRRN3 to CD38 expression and telomerase activity, two strong predictors of HIV disease progression. Our analysis revealed that reduced ADA, telomerase activity and LRRN3 gene expression were significantly associated with high CD38 and HLA-DR in CD8+ T cells, with % ADA+ cells being the most robust predictor of CD8+ T cell activation. Our results suggest that ADA, LRRN3 and telomerase activity in CD8+ T cells may serve as novel, clinically relevant biomarkers of immune status in HIV-1 infection, specifically by demonstrating the degree to which CD8+ T cells have progressed to the end stage of replicative senescence. Since chronological aging itself leads to the accumulation of senescent CD8+ T cells, the prolonged survival and resultant increased age of the HIV+ population may synergize with the chronic immune activation to exacerbate both immune decline and age-associated pathologies. The identification and future validation of these new biomarkers may lead to fresh immune-based HIV treatments.

  16. Neonatal CD8+ T-cell differentiation is dependent on interleukin-12.

    LENUS (Irish Health Repository)

    McCarron, Mark J

    2012-02-01

    Neonatal CD8(+) T-cell activation is significantly impaired compared with that in adults. Recent studies have demonstrated that interleukin (IL)-12 is necessary as a third signal, in addition to antigen and co-stimulation, to authorize the differentiation of naive CD8(+) T cells. We examined whether human neonatal CD8(+) T cells, which possess an exclusively naive T-cell phenotype, required a third signal to authorize a productive T-cell response. IL-12 enhanced activated naive CD8(+) T-cell survival, expansion, CD25 expression, and IL-2 production. Activated CD8(+) T cells produced interferon-gamma and intracellular granzyme B and were cytotoxic only in the presence of IL-12. Sustained IL-12 signaling for 72 hours was required for optimal interferon-gamma production. IL-12, in concert with T cell receptor (TCR) stimulation, sustained late-stage (48-72 hours) intracellular phosphorylation and particularly total protein levels of the proximal TCR components, Lck, and CD3xi. The requirement for a third signal for productive human neonatal CD8(+) T-cell differentiation may have implications for neonatal vaccination strategies.

  17. CD8 T cells express randomly selected KIRs with distinct specificities compared with NK cells

    Science.gov (United States)

    Béziat, Vivien; Cichocki, Frank; Liu, Lisa L.; Levine, Jeffrey; Larsson, Stella; Koup, Richard A.; Anderson, Stephen K.; Ljunggren, Hans-Gustaf

    2012-01-01

    Epistatic interactions between killer cell immunoglobulin-like receptors (KIRs) and their cognate HLA class I ligands have important implications for reproductive success, antiviral immunity, susceptibility to autoimmune conditions and cancer, as well as for graft-versus-leukemia reactions in settings of allogeneic stem cell transplantation. Although CD8 T cells are known to acquire KIRs when maturing from naive to terminally differentiated cells, little information is available about the constitution of KIR repertoires on human CD8 T cells. Here, we have performed a high-resolution analysis of KIR expression on CD8 T cells. The results show that most CD8 T cells possess a restricted KIR expression pattern, often dominated by a single activating or inhibitory KIR. Furthermore, the expression of KIR, and its modulation of CD8 T-cell function, was independent of expression of self-HLA class I ligands. Finally, despite similarities in the stochastic regulation of KIRs by the bidirectional proximal promoter, the specificity of inhibitory KIRs on CD8 T cells was often distinct from that of natural killer cells in the same individual. The results provide new insight into the formation of KIR repertoires on human T cells. PMID:22968455

  18. Investigation of Chemokine Receptor CCR2V64Il Gene Polymorphism and Migraine without Aura in the Iranian Population

    Directory of Open Access Journals (Sweden)

    Alireza Zandifar

    2013-01-01

    Full Text Available Background and Objectives. Migraine is a multifactorial common neurovascular disease with a polygenic inheritance. Inflammation plays an important part in migraine pathophysiology. C-C chemokine receptor 2 (CCR2 is an important chemokine for monocyte aggregation and transendothelial monocyte migration. The aim of our study was to investigate the association of migraine with CCR2V64Il polymorphism in the Iranian population. Methods. We assessed 103 patients with newly diagnosed migraine and 100 healthy subjects. Genomic DNA samples were extracted from peripheral blood and genotypes of CCR2V64Il gene polymorphism were determined. For measuring the severity of headache, every patient filled out the MIGSEV questionnaire. Results. There were no significant differences in the distribution of both 64Il allele and heterozygote (GA genotype of CCR2 gene polymorphism (P=0.396; OR=0.92, 95% CI = 0.50–1.67 and P=0.388; OR=0.91, 95% CI = 0.47–1.73, resp. between case and control groups. There was no significant difference of alleles frequency between three grades of MIGSEV (P=0.922. Conclusions. In conclusion our results revealed no association between CCR2V64Il polymorphism and susceptibility to migraine and also headache severity in the Iranian population.

  19. The Staphylococcal Toxins γ-Hemolysin AB and CB Differentially Target Phagocytes by Employing Specific Chemokine Receptors

    Science.gov (United States)

    Spaan, András N.; Vrieling, Manouk; Wallet, Pierre; Badiou, Cédric; Reyes-Robles, Tamara; Ohneck, Elizabeth A.; Benito, Yvonne; de Haas, Carla J.C.; Day, Christopher J.; Jennings, Michael P.; Lina, Gérard; Vandenesch, François; van Kessel, Kok P.M.; Torres, Victor J.; van Strijp, Jos A.G.; Henry, Thomas

    2014-01-01

    Evasion of the host phagocyte response by Staphylococcus aureus is crucial to successful infection with the pathogen. γ-Hemolysin AB and CB (HlgAB, HlgCB) are bicomponent pore-forming toxins present in almost all human S. aureus isolates. Cellular tropism and contribution of the toxins to S. aureus pathophysiology are poorly understood. Here, we identify the chemokine receptors CXCR1, CXCR2 and CCR2 as targets for HlgAB, and the complement receptors C5aR and C5L2 as targets for HlgCB. The receptor expression patterns allow the toxins to efficiently and differentially target phagocytic cells. Murine neutrophils are resistant to HlgAB and HlgCB. CCR2 is the sole murine receptor orthologue compatible with γ-Hemolysin. In a murine peritonitis model, HlgAB contributes to S. aureus bacteremia in a CCR2-dependent manner. HlgAB-mediated targeting of CCR2+ cells highlights the involvement of inflammatory macrophages during S. aureus infection. Functional quantification identifies HlgAB and HlgCB as major secreted staphylococcal leukocidins. PMID:25384670

  20. The role of CXC chemokine ligand (CXCL)12-CXC chemokine receptor (CXCR)4 signalling in the migration of neural stem cells towards a brain tumour

    NARCIS (Netherlands)

    van der Meulen, A. A. E.; Biber, K.; Lukovac, S.; Balasubramaniyan, V.; den Dunnen, W. F. A.; Boddeke, H. W. G. M.; Mooij, J. J. A.

    2009-01-01

    Aims: It has been shown that neural stem cells (NSCs) migrate towards areas of brain injury or brain tumours and that NSCs have the capacity to track infiltrating tumour cells. The possible mechanism behind the migratory behaviour of NSCs is not yet completely understood. As chemokines are involved

  1. Alterations in Activation, Cytotoxic Capacity and Trafficking Profile of Peripheral CD8 T Cells in Young Adult Binge Drinkers.

    Directory of Open Access Journals (Sweden)

    José Luis Zaldivar Fujigaki

    Full Text Available Excess of alcohol consumption is a public health problem and has documented effects on the immune system of humans and animals. Animal and in vitro studies suggest that alcohol abuse changes CD8 T cell (CD8 characteristics, however it remains unknown if the CD8 profile of binge drinkers is different in terms of activation, trafficking and cytotoxic capacity.To analyze the peripheral CD8 cytotoxic capacity, activation and trafficking phenotypic profile of Mexican young adults with regard to alcohol consumption pattern.55 Mexican young adults were stratified as Light (20, Intermediate (18 or Binge drinkers (17 according to their reported alcohol consumption pattern. Blood samples were obtained and hematic biometry and liver enzyme analysis were performed. Peripheral CD8 profile was established by expression of Granzyme B (GB, CD137, CD127, CD69, TLR4, PD1, CCR2, CCR4, CCR5 and CXCR4 by FACS. Data was analyzed by ANOVA, posthoc DMS and Tamhane, and principal component analysis (PCA with varimax rotation, p<0.05.The Binge drinking group showed increased γGT together with increased expression of CD69 and reduced expression of TLR4, PD1, CCR2 and CXCR4 in peripheral CD8 cells. Other parameters were also specific to Binge drinkers. PCA established 3 factors associated with alcohol consumption: "Early Activation" represented by CD69 and TLR4 expression in the CD8 population; "Effector Activation" by CD69 expression in CD8 CD127(+CD137(+ and CD8 CD25(+ CD137(+; and Trafficking by CXCR4 expression on total CD8 and CD8 GB(+CXCR4(+, and CCR2 expression on total CD8. Binge drinking pattern showed low expression of Early Activation and Trafficking factors while Light drinking pattern exhibited high expression of Effector Activation factor.Alcohol consumption affects the immune phenotype of CD8 cells since binge drinking pattern was found to be associated with high CD69 and low TLR4, CXCR4 and CCR2 expression, which suggest recent activation, decreased

  2. CD8 T cell persistence in treated HIV infection

    Science.gov (United States)

    Mudd, J. C.; Lederman, Michael M

    2014-01-01

    Purpose of review Many treated HIV infected persons maintain persistently high circulating CD8 T cell numbers, even after many years of therapy. Recent reports suggest that persistent CD8 T cell expansion is associated with higher risk of morbid non-AIDS events. Thus, assessing the mechanisms of CD8 T cell expansion and persistence may give insights into a feature of HIV disease that is clinically important. Recent findings Acute HIV infection is associated with activation and expansion of the CD8 T cell compartment. Expanded CD8 T cells persist throughout disease course and, in contrast to the plasticity that typically characterizes immune responses to most other pathogens, circulating CD8 T cell numbers do not normalize in many patients despite pharmacological suppression of HIV replication. We suspect that residual inflammation in treated HIV infection contributes to antigen-independent CD8 T cell expansion and persistence as most of these cells are not HIV-reactive. Summary Circulating CD8 T cell numbers remain abnormally elevated in many treated HIV-infected patients and this elevation is associated with adverse clinical events. Future studies will need to assess the mechanisms of CD8 T cell expansion and to define the role of CD8 lymphocytosis in the clinical course of treated HIV disease. PMID:25010897

  3. The human herpes virus 8-encoded chemokine receptor is required for angioproliferation in a murine model of Kaposi's sarcoma

    DEFF Research Database (Denmark)

    Jensen, Kristian K; Manfra, Denise J; Grisotto, Marcos G

    2005-01-01

    active G protein-coupled receptor known as vGPCR that binds CXC chemokines with high affinity. In this study, we show that conditional transgenic expression of vGPCR by cells of endothelial origin triggers an angiogenic program in vivo, leading to development of an angioproliferative disease...... that resembles KS. This angiogenic program consists partly in the expression of the angiogenic factors placental growth factor, platelet-derived growth factor B, and inducible NO synthase by the vGPCR-expressing cells. Finally, we show that continued vGPCR expression is essential for progression of the KS......-like phenotype and that down-regulation of vGPCR expression results in reduced expression of angiogenic factors and regression of the lesions. Together, these findings implicate vGPCR as a key element in KS pathogenesis and suggest that strategies to block its function may represent a novel approach...

  4. Selective chemokine receptor usage by central nervous system myeloid cells in CCR2-red fluorescent protein knock-in mice.

    Directory of Open Access Journals (Sweden)

    Noah Saederup

    2010-10-01

    Full Text Available Monocyte subpopulations distinguished by differential expression of chemokine receptors CCR2 and CX3CR1 are difficult to track in vivo, partly due to lack of CCR2 reagents.We created CCR2-red fluorescent protein (RFP knock-in mice and crossed them with CX3CR1-GFP mice to investigate monocyte subset trafficking. In mice with experimental autoimmune encephalomyelitis, CCR2 was critical for efficient intrathecal accumulation and localization of Ly6C(hi/CCR2(hi monocytes. Surprisingly, neutrophils, not Ly6C(lo monocytes, largely replaced Ly6C(hi cells in the central nervous system of these mice. CCR2-RFP expression allowed the first unequivocal distinction between infiltrating monocytes/macrophages from resident microglia.These results refine the concept of monocyte subsets, provide mechanistic insight about monocyte entry into the central nervous system, and present a novel model for imaging and quantifying inflammatory myeloid populations.

  5. RTN3 Regulates the Expression Level of Chemokine Receptor CXCR4 and is Required for Migration of Primordial Germ Cells

    Directory of Open Access Journals (Sweden)

    Haitao Li

    2016-04-01

    Full Text Available CXCR4 is a crucial chemokine receptor that plays key roles in primordial germ cell (PGC homing. To further characterize the CXCR4-mediated migration of PGCs, we screened CXCR4-interacting proteins using yeast two-hybrid screening. We identified reticulon3 (RTN3, a member of the reticulon family, and considered an apoptotic signal transducer, as able to interact directly with CXCR4. Furthermore, we discovered that the mRNA and protein expression levels of CXCR4 could be regulated by RTN3. We also found that RTN3 altered CXCR4 translocation and localization. Moreover, increasing the signaling of either CXCR4b or RTN3 produced similar PGC mislocalization phenotypes in zebrafish. These results suggested that RTN3 modulates PGC migration through interaction with, and regulation of, CXCR4.

  6. A randomized controlled trial of the efficacy and safety of CCX282-B, an orally-administered blocker of chemokine receptor CCR9, for patients with Crohn's disease

    DEFF Research Database (Denmark)

    Keshav, Satish; Vaňásek, Tomáš; Niv, Yaron

    2013-01-01

    CCX282-B, also called vercirnon, is a specific, orally-administered chemokine receptor CCR9 antagonist that regulates migration and activation of inflammatory cells in the intestine. This randomized, placebo-controlled trial was conducted to evaluate the safety and efficacy of CCX282-B in 436...

  7. A closed-tube assay for genotyping of the 32-bp deletion polymorphism in the chemokine receptor 5 (CCR5) gene

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Berg; Werge, Thomas

    2007-01-01

    We have developed a closed-tube assay for determination of the chemokine receptor type 5 (CCR5) 32-bp deletion allele, which protects against infections with HIV and modulates susceptibility to a variety of inflammatory diseases. This assay utilizes dissociation analysis of amplified products...

  8. Pharmacological characterization of [3H]VUF11211, a novel radiolabeled small-molecule inverse agonist for the chemokine receptor CXCR3

    NARCIS (Netherlands)

    Scholten, Danny J; Wijtmans, M.; van Senten, Jeffrey R; Custers, Hans; Stunnenberg, Ailas; de Esch, Iwan J P; Smit, Martine J; Leurs, Rob

    Chemokine receptor CXCR3 has attracted much attention, as it is thought to be associated with a wide range of immune-related diseases. As such, several small molecules with different chemical structures targeting CXCR3 have been discovered. Despite limited clinical success so far, these compounds

  9. Effects of radiation combined injury on hippocampal function are modulated in mice deficient in chemokine receptor 2 (CCR2).

    Science.gov (United States)

    Allen, Antiño R; Eilertson, Kirsten; Sharma, Sourabh; Schneider, Danielle; Baure, Jennifer; Allen, Barrett; Rosi, Susanna; Raber, Jacob; Fike, John R

    2013-07-01

    Chemokines and their receptors play a crucial role in normal brain function as well as in pathological conditions such as injury and disease-associated neuroinflammation. Chemokine receptor-2 (CCR2), which mediates the recruitment of infiltrating and resident microglia to sites of central nervous system (CNS) inflammation, is upregulated by ionizing irradiation and traumatic brain injury. Our objective was to determine if a deficiency in CCR2 and subsequent effects on brain microglia affect neurogenesis and cognitive function after radiation combined injury (RCI). CCR2 knock-out ⁻/⁻ and wild-type (WT) mice received 4 Gy of whole body ¹³⁷Cs irradiation. Immediately after irradiation, unilateral traumatic brain injury was induced using a controlled cortical impact system. Forty-four days postirradiation, animals were tested for hippocampus-dependent cognitive performance in the Morris water-maze. After cognitive testing, animals were euthanized and their brains snap frozen for immunohistochemical assessment of neuroinflammation (activated microglia) and neurogenesis in the hippocampal dentate gyrus. All animals were able to locate the visible and hidden platform locations in the water maze; however, treatment effects were seen when spatial memory retention was assessed in the probe trials (no platform). In WT animals that received combined injury, a significant impairment in spatial memory retention was observed in the probe trial after the first day of hidden platform training (first probe trial). This impairment was associated with increased neurogenesis in the ipsilateral hemisphere of the dentate gyrus. In contrast, CCR2⁻/⁻ mice, independent of insult showed significant memory retention in the first probe trial and there were no differences in the numbers of newly born neurons in the animals receiving irradiation, trauma or combined injury. Although the mechanisms involved are not clear, our data suggests that CCR2 deficiency can exert a protective

  10. Temporal kinetics of CD8+CD28+and CD8+CD28-T lymphocytes in the injured rat spinal cord.

    Science.gov (United States)

    Wu, Yan; Lin, Yu-Hong; Shi, Ling-Ling; Yao, Zong-Feng; Xie, Xiu-Mei; Jiang, Zheng-Song; Tang, Jie; Hu, Jian-Guo; Lü, He-Zuo

    2017-08-01

    This study aims to explore the temporal changes of cytotoxic CD8 + CD28 + and regulatory CD8 + CD28 - T-cell subsets in the lesion microenvironment after spinal cord injury (SCI) in rats, by combination of immunohistochemistry (IHC) and flow cytometry (FCM). In the sham-opened spinal cord, few CD8 + T cells were found. After SCI, the CD8 + T cells were detected at one day post-injury (dpi), then markedly increased and were significantly higher at 3, 7, and 14 dpi compared with one dpi (p CD8 + T cells, more than 90% were CD28 + , and there were only small part of CD28 - ( CD8 + T cells were significantly decreased, and few could be found in good condition at 21 and 28 dpi. Annexin V and propidium iodide (PI) staining showed that the percentages of apoptotic/necrotic CD8 + cells at 14 dpi and 21 dpi were significantly higher than those of the other early time-points (p CD8 + T cells could rapidly infiltrate into the injured spinal cords and survive two weeks, however, cytotoxic CD8 + T cells were dominant. Therefore, two weeks after injury might be the "time window" for treating SCI by prolonging survival times and increasing the fraction of CD8 + regulatory T-cells. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Expansion of CD8+ cells in autoimmune hemolytic anemia.

    Science.gov (United States)

    Smirnova, S Ju; Sidorova, Ju V; Tsvetaeva, N V; Nikulina, O F; Biderman, B V; Nikulina, E E; Kulikov, S M; Sudarikov, A B

    2016-01-01

    Autoimmune hemolytic anemia (AIHA) is a rare blood disease associated with the production of auto-antibodies and autoimmune hemolysis. A critical role of B-cells in the development of AIHA has been demonstrated before. Here, we present the analysis of the clonal T-cell populations in patients with AIHA. Thirty-three patients with AIHA were included in this study. Thirteen patients with other anemias, 14 patients with other autoimmune conditions (SLE - 6, RA - 8) and 20 healthy donors were included in the study as a control group. The clonality of T-cell was evaluated by the assessment of the T-cell receptor gamma and beta chain gene rearrangements (TCRG and TCRB). The incidence of T-cell monoclonality detected in patients with AIHA was significantly higher compared to the control group. The persistence of T-cell clones did not correlate with the level of hemoglobin and other signs of remission or relapse and did not disappear after the therapy and clinical improvement (observation period was between 1 and 10 years). There was no correlation between the T-cell clonality and the gender, age, splenectomy, duration or severity of the disease. Fractionation of T-lymphocytes (CD4+, CD8+, CD4+25+) revealed that the monoclonal T-cells belonged to the CD8+ sub-population. We assume that besides a possible causative role of the T-cell clones in AIHA to autoimmune process, these clones do not directly participate in the development and maintenance of hemolysis. Most of the AIHA patients (48.5%) demonstrated a T-cell monoclonality, which requires monitoring and should be distinguished from T-cell tumors.

  12. Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveals a Mechanism for Regulation of Tumor Progression.

    Science.gov (United States)

    Coke, Christopher J; Scarlett, Kisha A; Chetram, Mahandranauth A; Jones, Kia J; Sandifer, Brittney J; Davis, Ahriea S; Marcus, Adam I; Hinton, Cimona V

    2016-05-06

    The G-protein-coupled chemokine receptor CXCR4 generates signals that lead to cell migration, cell proliferation, and other survival mechanisms that result in the metastatic spread of primary tumor cells to distal organs. Numerous studies have demonstrated that CXCR4 can form homodimers or can heterodimerize with other G-protein-coupled receptors to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor. Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells. Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2 and ultimately reduced cancer cell functions such as calcium mobilization and cellular chemotaxis. Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells as well as CXCR4-mediated migration of immune cells, it is plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4. Taken together, the data illustrate a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function and perhaps tumor progression. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Superior antigen cross-presentation and XCR1 expression define human CD11c+CD141+ cells as homologues of mouse CD8+ dendritic cells.

    Science.gov (United States)

    Bachem, Annabell; Güttler, Steffen; Hartung, Evelyn; Ebstein, Frédéric; Schaefer, Michael; Tannert, Astrid; Salama, Abdulgabar; Movassaghi, Kamran; Opitz, Corinna; Mages, Hans W; Henn, Volker; Kloetzel, Peter-Michael; Gurka, Stephanie; Kroczek, Richard A

    2010-06-07

    In recent years, human dendritic cells (DCs) could be subdivided into CD304+ plasmacytoid DCs (pDCs) and conventional DCs (cDCs), the latter encompassing the CD1c+, CD16+, and CD141+ DC subsets. To date, the low frequency of these DCs in human blood has essentially prevented functional studies defining their specific contribution to antigen presentation. We have established a protocol for an effective isolation of pDC and cDC subsets to high purity. Using this approach, we show that CD141+ DCs are the only cells in human blood that express the chemokine receptor XCR1 and respond to the specific ligand XCL1 by Ca2+ mobilization and potent chemotaxis. More importantly, we demonstrate that CD141+ DCs excel in cross-presentation of soluble or cell-associated antigen to CD8+ T cells when directly compared with CD1c+ DCs, CD16+ DCs, and pDCs from the same donors. Both in their functional XCR1 expression and their effective processing and presentation of exogenous antigen in the context of major histocompatibility complex class I, human CD141+ DCs correspond to mouse CD8+ DCs, a subset known for superior antigen cross-presentation in vivo. These data define CD141+ DCs as professional antigen cross-presenting DCs in the human.

  14. CD8+ T cells in Leishmania infections: friends or foes?

    Directory of Open Access Journals (Sweden)

    Simona eStager

    2012-01-01

    Full Text Available Host protection against several intracellular pathogens requires the induction of CD8+ T cell responses. CD8+ T cells are potent effector cells that can produce high amounts of pro-inflammatory cytokines and kill infected target cells efficiently. However, a protective role for CD8+ T cells during Leishmania infections is still controversial and largely depends on the infection model. In this review, we discuss the role of CD8+ T cells during various types Leishmania infections, following vaccination, and as potential immunotherapeutic targets.

  15. Public TCR Use by Herpes Simplex Virus-2-Specific Human CD8 CTLs

    NARCIS (Netherlands)

    Dong, Lichun; Li, Penny; Oenema, Tjitske; McClurkan, Christopher L.; Koelle, David M.

    2010-01-01

    Recombination of germline TCR alpha and beta genes generates polypeptide receptors for MHC peptide. Ag exposure during long-term herpes simplex infections may shape the T cell repertoire over time. We investigated the CD8 T cell response to HSV-2 in chronically infected individuals by sequencing the

  16. Alterations in Activation, Cytotoxic Capacity and Trafficking Profile of Peripheral CD8 T Cells in Young Adult Binge Drinkers.

    Science.gov (United States)

    Zaldivar Fujigaki, José Luis; Arroyo Valerio, América Guadalupe; López Alvarenga, Juan Carlos; Gutiérrez Reyes, Esperanza Gabriela; Kershenobich, David; Hernández Ruiz, Joselin

    2015-01-01

    Excess of alcohol consumption is a public health problem and has documented effects on the immune system of humans and animals. Animal and in vitro studies suggest that alcohol abuse changes CD8 T cell (CD8) characteristics, however it remains unknown if the CD8 profile of binge drinkers is different in terms of activation, trafficking and cytotoxic capacity. To analyze the peripheral CD8 cytotoxic capacity, activation and trafficking phenotypic profile of Mexican young adults with regard to alcohol consumption pattern. 55 Mexican young adults were stratified as Light (20), Intermediate (18) or Binge drinkers (17) according to their reported alcohol consumption pattern. Blood samples were obtained and hematic biometry and liver enzyme analysis were performed. Peripheral CD8 profile was established by expression of Granzyme B (GB), CD137, CD127, CD69, TLR4, PD1, CCR2, CCR4, CCR5 and CXCR4 by FACS. Data was analyzed by ANOVA, posthoc DMS and Tamhane, and principal component analysis (PCA) with varimax rotation, palcohol consumption: "Early Activation" represented by CD69 and TLR4 expression in the CD8 population; "Effector Activation" by CD69 expression in CD8 CD127(+)CD137(+) and CD8 CD25(+) CD137(+); and Trafficking by CXCR4 expression on total CD8 and CD8 GB(+)CXCR4(+), and CCR2 expression on total CD8. Binge drinking pattern showed low expression of Early Activation and Trafficking factors while Light drinking pattern exhibited high expression of Effector Activation factor. Alcohol consumption affects the immune phenotype of CD8 cells since binge drinking pattern was found to be associated with high CD69 and low TLR4, CXCR4 and CCR2 expression, which suggest recent activation, decreased sensitivity to LPS and lower migration capacity in response to chemokines SDF-1 and MCP-1. These results indicate that a binge-drinking pattern of alcohol consumption may induce an altered immune profile that could be related with liver damage and the increased susceptibility to

  17. TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15.

    Science.gov (United States)

    Villanueva, Jeanette E; Malle, Elisabeth K; Gardam, Sandra; Silveira, Pablo A; Zammit, Nathan W; Walters, Stacey N; Brink, Robert; Grey, Shane T

    2015-06-01

    In this study, a critical and novel role for TNF receptor (TNFR) associated factor 2 (TRAF2) is elucidated for peripheral CD8(+) T-cell and NKT-cell homeostasis. Mice deficient in TRAF2 only in their T cells (TRAF2TKO) show ∼40% reduction in effector memory and ∼50% reduction in naïve CD8(+) T-cell subsets. IL-15-dependent populations were reduced further, as TRAF2TKO mice displayed a marked ∼70% reduction in central memory CD8(+) CD44(hi) CD122(+) T cells and ∼80% decrease in NKT cells. TRAF2TKO CD8(+) CD44(hi) T cells exhibited impaired dose-dependent proliferation to exogenous IL-15. In contrast, TRAF2TKO CD8(+) T cells proliferated normally to anti-CD3 and TRAF2TKO CD8(+) CD44(hi) T cells exhibited normal proliferation to exogenous IL-2. TRAF2TKO CD8(+) T cells expressed normal levels of IL-15-associated receptors and possessed functional IL-15-mediated STAT5 phosphorylation, however TRAF2 deletion caused increased AKT activation. Loss of CD8(+) CD44(hi) CD122(+) and NKT cells was mechanistically linked to an inability to respond to IL-15. The reduced CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell populations in TRAF2TKO mice were rescued in the presence of high dose IL-15 by IL-15/IL-15Rα complex administration. These studies demonstrate a critical role for TRAF2 in the maintenance of peripheral CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell homeostasis by modulating sensitivity to T-cell intrinsic growth factors such as IL-15. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Peroxisome proliferator-activated receptor α agonists modulate Th1 and Th2 chemokine secretion in normal thyrocytes and Graves' disease

    International Nuclear Information System (INIS)

    Antonelli, Alessandro; Ferrari, Silvia Martina; Frascerra, Silvia; Corrado, Alda; Pupilli, Cinzia; Bernini, Giampaolo; Benvenga, Salvatore; Ferrannini, Ele; Fallahi, Poupak

    2011-01-01

    Until now, no data are present about the effect of peroxisome proliferator-activated receptor (PPAR)α activation on the prototype Th1 [chemokine (C-X-C motif) ligand (CXCL)10] (CXCL10) and Th2 [chemokine (C-C motif) ligand 2] (CCL2) chemokines secretion in thyroid cells. The role of PPARα and PPARγ activation on CXCL10 and CCL2 secretion was tested in Graves' disease (GD) and control primary thyrocytes stimulated with interferon (IFN)γ and tumor necrosis factor (TNF)α. IFNγ stimulated both CXCL10 and CCL2 secretion in primary GD and control thyrocytes. TNFα alone stimulated CCL2 secretion, while had no effect on CXCL10. The combination of IFNγ and TNFα had a synergistic effect both on CXCL10 and CCL2 chemokines in GD thyrocytes at levels comparable to those of controls. PPARα activators inhibited the secretion of both chemokines (stimulated with IFNγ and TNFα) at a level higher (for CXCL10, about 60-72%) than PPARγ agonists (about 25-35%), which were confirmed to inhibit CXCL10, but not CCL2. Our data show that CCL2 is modulated by IFNγ and TNFα in GD and normal thyrocytes. Furthermore we first show that PPARα activators inhibit the secretion of CXCL10 and CCL2 in thyrocytes, suggesting that PPARα may be involved in the modulation of the immune response in the thyroid.

  19. Role of CD8+ regulatory T cells in organ transplantation

    Directory of Open Access Journals (Sweden)

    Jiyan Su

    2014-01-01

    Full Text Available CD8 + T cells are regulatory T cells (Tregs that suppress both alloimmunity and autoimmunity in many animal models. This class of regulatory cells includes the CD8 + CD28 - , CD8 + CD103 + , CD8 + FoxP3 + and CD8 + CD122 + subsets. The mechanisms of action of these regulatory cells are not fully understood; however, the secretion of immunosuppressive cytokines, such as interleukin (IL-4, IL-10 and transforming growth factor beta (TGF-β as well as the direct killing of target cells via Fas L/Fas and the perforin/granzyme B pathways have been demonstrated in various models. Further studies are necessary to fully understand the mechanisms underlying the suppressive effects of Tregs and to provide experimental support for potential clinical trials. We recently observed that CD8 + CD122 + Tregs more potently suppressed allograft rejection compared to their CD4 + CD25 + counterparts, supporting the hypothesis that CD8 + Tregs may represent a new and promising Treg family that can be targeted to prevent allograft rejection in the clinic. In this review, we summarize the progress in the field during the past 7-10 years and discuss CD8 + Treg phenotypes, mechanisms of action, and their potential clinical applications; particularly in composite tissue transplants in burn and trauma patients.

  20. Exploring a model of human chemokine receptor CCR2 in presence of TAK779: A membrane based molecular dynamics study

    Science.gov (United States)

    Balupuri, Anand; Sobhia, M. Elizabeth

    2014-04-01

    Chemokine receptor 2 (CCR2) is a G-protein coupled receptor (GPCR) and a crucial target for various inflammation-driven diseases. In the present study, molecular docking and molecular dynamics simulations were performed on a CCR2 homology model. This work includes the comparative MD simulations of uncomplexed and ‘antagonist-complexed’ CCR2 models. These simulations yield insights into the binding mechanism of antagonist TAK779 and improve the understanding of various structural changes induced by the ligand in the CCR2 protein. Here, one 20 ns MD simulation was carried out on the uncomplexed CCR2 model in lipid bilayer to explore the effects of lipid membrane on the protein. Another 20 ns MD simulation was performed under the similar conditions on the docked CCR2-TAK779 complex. An alteration in the position and orientation of the ligand in binding site was observed after the simulation. Examination of protein-ligand complex suggested that TAK779 produced a greater structural change on the TM-III, TM-IV, TM-V and TM-VI than TM-I, TM-II and TM-VII. Interaction networks involving the conserved residues of uncomplexed and ‘antagonist-complexed’ CCR2 models were also examined. The major difference was observed to be the role of conserved residues of the DRY motif of TM-III and the NPxxY motif of TM-VII of CCR2.

  1. Met receptor tyrosine kinase signaling induces secretion of the angiogenic chemokine interleukin-8/CXCL8 in pancreatic cancer.

    Directory of Open Access Journals (Sweden)

    Kristen S Hill

    Full Text Available At diagnosis, the majority of pancreatic cancer patients present with advanced disease when curative resection is no longer feasible and current therapeutic treatments are largely ineffective. An improved understanding of molecular targets for effective intervention of pancreatic cancer is thus urgent. The Met receptor tyrosine kinase is one candidate implicated in pancreatic cancer. Notably, Met is over expressed in up to 80% of invasive pancreatic cancers but not in normal ductal cells correlating with poor overall patient survival and increased recurrence rates following surgical resection. However the functional role of Met signaling in pancreatic cancer remains poorly understood. Here we used RNA interference to directly examine the pathobiological importance of increased Met signaling for pancreatic cancer. We show that Met knockdown in pancreatic tumor cells results in decreased cell survival, cell invasion, and migration on collagen I in vitro. Using an orthotopic model for pancreatic cancer, we provide in vivo evidence that Met knockdown reduced tumor burden correlating with decreased cell survival and tumor angiogenesis, with minimal effect on cell growth. Notably, we report that Met signaling regulates the secretion of the pro-angiogenic chemokine interleukin-8/CXCL8. Our data showing that the interleukin-8 receptors CXCR1 and CXCR2 are not expressed on pancreatic tumor cells, suggests a paracrine mechanism by which Met signaling regulates interleukin-8 secretion to remodel the tumor microenvironment, a novel finding that could have important clinical implications for improving the effectiveness of treatments for pancreatic cancer.

  2. Elevated chemokine CC-motif receptor-like 2 (CCRL2) promotes cell migration and invasion in glioblastoma.

    Science.gov (United States)

    Yin, Fengqiong; Xu, Zhenhua; Wang, Zifeng; Yao, Hong; Shen, Zan; Yu, Fang; Tang, Yiping; Fu, Dengli; Lin, Sheng; Lu, Gang; Kung, Hsiang-Fu; Poon, Wai Sang; Huang, Yunchao; Lin, Marie Chia-Mi

    2012-12-14

    Chemokine CC-motif receptor-like 2 (CCRL2) is a 7-transmembrane G protein-coupled receptor which plays a key role in lung dendritic cell trafficking to peripheral lymph nodes. The function and expression of CCRL2 in cancer is not understood at present. Here we report that CCRL2 expression level is elevated in human glioma patient samples and cell lines. The magnitude of increase is positively associated with increasing tumor grade, with the highest level observed in grade IV glioblastoma. By gain-of-function and loss-of-function studies, we further showed that CCRL2 did not regulate the growth of human glioblatoma U87 and U373 cells. Importantly, we demonstrated that over-expression of CCRL2 significantly enhanced the migration rate and invasiveness of the glioblastoma cells. Taken together, these results suggest for the first time that elevated CCRL2 in glioma promotes cell migration and invasion. The potential roles of CCRL2 as a novel therapeutic target and biomarker warrant further investigations. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Exhaustion of the CD8+T Cell Compartment in Patients with Mutations in Phosphoinositide 3-Kinase Delta.

    Science.gov (United States)

    Wentink, Marjolein W J; Mueller, Yvonne M; Dalm, Virgil A S H; Driessen, Gertjan J; van Hagen, P Martin; van Montfrans, Joris M; van der Burg, Mirjam; Katsikis, Peter D

    2018-01-01

    Pathogenic gain-of-function mutations in the gene encoding phosphoinositide 3-kinase delta (PI3Kδ) cause activated PI3Kδ syndrome (APDS), a disease characterized by humoral immunodeficiency, lymphadenopathy, and an inability to control persistent viral infections including Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infections. Understanding the mechanisms leading to impaired immune response is important to optimally treat APDS patients. Immunosenescence of CD8 + T cells was suggested to contribute to APDS pathogenesis. However, the constitutive activation of T cells in APDS may also result in T cell exhaustion. Therefore, we studied exhaustion of the CD8 + T cell compartment in APDS patients and compared them with healthy controls and HIV patients, as a control for exhaustion. The subset distribution of the T cell compartment of APDS patients was comparable with HIV patients with decreased naive CD4 + and CD8 + T cells and increased effector CD8 + T cells. Like in HIV + patients, expression of activation markers and inhibitory receptors CD160, CD244, and programmed death receptor (PD)-1 on CD8 + T cells was increased in APDS patients, indicating exhaustion. EBV-specific CD8 + T cells from APDS patients exhibited an exhausted phenotype that resembled HIV-specific CD8 + T cells in terms of inhibitory receptor expression. Inhibition of PD-1 on EBV-specific CD8 + T cells from APDS patients enhanced in vitro proliferation and effector cytokine production. Based on these results, we conclude that total and EBV-specific CD8 + T cells from APDS patients are characterized by T cell exhaustion. Furthermore, PD-1 checkpoint inhibition may provide a possible therapeutic approach to support the immune system of APDS patients to control EBV and CMV.

  4. Chemokine Receptor CCR5 Antagonist Maraviroc: Medicinal Chemistry and Clinical Applications

    Science.gov (United States)

    Xu, Guoyan G.; Guo, Jia; Wu, Yuntao

    2015-01-01

    The human immunodeficiency virus (HIV) causes acquired immumodeficiency syndrome (AIDS), one of the worst global pandemic. The virus infects human CD4 T cells and macrophages, and causes CD4 depletion. HIV enters target cells through the binding of the viral envelope glycoprotein to CD4 and the chemokine coreceptor, CXCR4 or CCR5. In particular, the CCR5-utilizing viruses predominate in the blood during the disease course. CCR5 is expressed on the surface of various immune cells including macrophages, monocytes, microglia, dendric cells, and active memory CD4 T cells. In the human population, the CCR5 genomic mutation, CCR5Δ32, is associated with relative resistance to HIV. These findings paved the way for the discovery and development of CCR5 inhibitors to block HIV transmission and replication. Maraviroc, discovered as a CCR5 antagonist, is the only CCR5 inhibitor that has been approved by both US FDA and the European Medicines Agency (EMA) for treating HIV/AIDS patients. In this review, we summarize the medicinal chemistry and clinical studies of Maraviroc. PMID:25159165

  5. Chemokines in tumor proximal fluids.

    Science.gov (United States)

    Kotyza, Jaromir

    2017-03-01

    Chemokines are chemotactic cytokines produced by leukocytes and other types of cells including tumor cells. Their action is determined by the expression of cognate receptors and subsequent signaling in target cells, followed by the modulation of cytoskeletal proteins and the induction of other responses. In tumors, chemokines produced by neoplastic/stroma cells control the leukocyte infiltrate influencing tumor growth and progression. Tumor cells also express functional chemokine receptors responding to chemokine signals, promoting cell survival, proliferation and metastasis formation. Chemokines may be detected in serum of cancer patients, but due to the paracrine nature of these molecules, more significant concentrations are found in the tumor adjacent, non-vascular fluids, collectively called tumor proximal fluids. This review summarizes the expression of CC and CXC chemokines in these fluids, namely in interstitial fluid, pleural, ascitic, and cyst fluids, but also in urine, saliva, cerebrospinal fluid, cervical secretions and bronchoalveolar lavage fluid. Most comparative clinical studies reveal increased chemokine levels in high-grade tumor proximal fluids rather than in low-grade tumors and benign conditions, indicating shorter survival periods. The data confirm peritumoral fluid chemokines as sensitive diagnostic and prognostic markers, as well as offer support for chemokines and their receptors as potential targets for antitumor therapy.

  6. HTLV-1 specific CD8+ T cell function augmented by blockade of 2B4/CD48 interaction in HTLV-1 infection.

    Directory of Open Access Journals (Sweden)

    Chibueze Chioma Ezinne

    Full Text Available CD8+ T cell response is important in the response to viral infections; this response though is regulated by inhibitory receptors. Expression of inhibitory receptors has been positively correlated with CD8+ T cell exhaustion; the consequent effect of simultaneous blockade of these inhibitory receptors on CD8+ T cell response in viral infections have been studied, however, the role of individual blockade of receptor-ligand pair is unclear. 2B4/CD48 interaction is involved in CD8+T cell regulation, its signal transducer SAP (signaling lymphocyte activation molecule (SLAM-associated protein is required for stimulatory function of 2B4/CD244 on lymphocytes hence, we analyzed 2B4/CD244 (natural killer cell receptor and SAP (signaling lymphocyte activation molecule(SLAM-associated protein on total CD8+ and HTLV-1 specific CD8+T cells in HTLV-1 infection and the effect of blockade of interaction with ligand CD48 on HTLV-1 specific CD8+ T cell function. We observed a high expression of 2B4/CD244 on CD8+ T cells relative to uninfected and further upregulation on HTLV-1 specific CD8+ T cells. 2B4+ CD8+ T cells exhibited more of an effector and terminally differentiated memory phenotype. Blockade of 2B4/CD48 interaction resulted in improvement in function via perforin expression and degranulation as measured by CD107a surface mobilization on HTLV-1 specific CD8+ T cells. In the light of these findings, we thus propose an inhibitory role for 2B4/CD48 interaction on CD8+T cell function.

  7. CD8+ memory T-cell inflation renders compromised CD4+ T-cell-dependent CD8+ T-cell immunity via naïve T-cell anergy

    Directory of Open Access Journals (Sweden)

    Xu A

    2017-06-01

    Full Text Available Aizhang Xu,1,2 Andrew Freywald,3 Yufeng Xie,4 Zejun Li,5 Jim Xiang1,2 1Cancer Research Cluster, Saskatchewan Cancer Agency, 2Department of Oncology, 3Department of Pathology, University of Saskatchewan, Saskatoon, SK, Canada; 4Department of Oncology, First Affiliated Hospital, Soochow University, Suzhou, 5Shanghai Veterinary Research Institute, Shanghai, China Abstract: Whether inflation of CD8+ memory T (mT cells, which is often derived from repeated prime-boost vaccinations or chronic viral infections in the elderly, would affect late CD8+ T-cell immunity is a long-standing paradox. We have previously established an animal model with mT-cell inflation by transferring ConA-stimulated monoclonal CD8+ T cells derived from Ova-specific T-cell-receptor transgenic OTI mice into irradiation-induced lymphopenic B6 mice. In this study, we also established another two animal models with mT-cell inflation by transferring, 1 ConA-stimulated monoclonal CD8+ T cells derived from lymphocytic choriomeningitis virus glycoprotein-specific T-cell-receptor transgenic P14 mice, and 2 ConA-stimulated polyclonal CD8+ T cells derived from B6.1 mice into B6 mice with irradiation-induced lymphopenia. We vaccinated these mice with recombinant Ova-expressing Listeria monocytogenes and Ova-pulsed dendritic cells, which stimulated CD4+ T cell-independent and CD4+ T-cell-dependent CD8+ T-cell responses, respectively, and assessed Ova-specific CD8+ T-cell responses by flow cytometry. We found that Ova-specific CD8+ T-cell responses derived from the latter but not the former vaccination were significantly reduced in mice with CD8+ mT-cell inflation compared to wild-type B6 mice. We determined that naïve CD8+ T cells purified from splenocytes of mice with mT-cell inflation had defects in cell proliferation upon stimulation in vitro and in vivo and upregulated T-cell anergy-associated Itch and GRAIL molecules. Taken together, our data reveal that CD8+ mT-cell inflation renders

  8. Identification of lineage-specifying cytokines that signal all CD8+-cytotoxic-lineage-fate 'decisions' in the thymus.

    Science.gov (United States)

    Etzensperger, Ruth; Kadakia, Tejas; Tai, Xuguang; Alag, Amala; Guinter, Terry I; Egawa, Takeshi; Erman, Batu; Singer, Alfred

    2017-11-01

    T cell antigen receptor (TCR) signaling in the thymus initiates positive selection, but the CD8 + -lineage fate is thought to be induced by cytokines after TCR signaling has ceased, although this remains controversial and unproven. We have identified four cytokines (IL-6, IFN-γ, TSLP and TGF-β) that did not signal via the common γ-chain (γ c ) receptor but that, like IL-7 and IL-15, induced expression of the lineage-specifying transcription factor Runx3d and signaled the generation of CD8 + T cells. Elimination of in vivo signaling by all six of these 'lineage-specifying cytokines' during positive selection eliminated Runx3d expression and completely abolished the generation of CD8 + single-positive thymocytes. Thus, this study proves that signaling during positive selection by lineage-specifying cytokines is responsible for all CD8 + -lineage-fate 'decisions' in the thymus.

  9. Development of Peptide Antagonists of Chemokine Receptors Involved in Breast Cancer Metastasis

    National Research Council Canada - National Science Library

    Blondelle, Sylvie E

    2004-01-01

    .... This was accomplished by screening in a competitive assay synthetic combinatorial libraries (SCLs) made up of D-amino acid peptides for their ability to antagonize CXCR4 receptor function using HeLa cells and PBMC cells (used as standard...

  10. Development of Peptide Antagonists of Chemokine Receptors Involved in Breast Cancer Metastasis

    National Research Council Canada - National Science Library

    Blondelle, Sylvie E

    2005-01-01

    .... This was accomplished by screening in a competitive assay synthetic combinatorial libraries (SCLs) made up of D-amino acid peptides for their ability to antagonize CXCR4 receptor function using HeLa cells and PBMC cells (used as standard...

  11. An extrafollicular pathway for the generation of effector CD8+ T cells driven by the proinflammatory cytokine, IL-12

    Science.gov (United States)

    Shah, Suhagi; Grotenbreg, Gijsbert M; Rivera, Amariliz; Yap, George S

    2015-01-01

    The proinflammatory cytokine IL-12 drives the generation of terminally differentiated KLRG1+ effector CD8+ T cells. Using a Toxoplasma vaccination model, we delineate the sequence of events that naïve CD8+ T cells undergo to become terminal effectors and the differentiation steps controlled by IL-12. We demonstrate that direct IL-12 signaling on CD8+ T cells is essential for the induction of KLRG1 and IFN-γ, but the subsequent downregulation of CXCR3 is controlled by IL-12 indirectly through the actions of IFN-γ and IFN-γ-inducible chemokines. Differentiation of nascent effectors occurs in an extrafollicular splenic compartment and is driven by late IL-12 production by DCs distinct from the classical CD8α+ DC. Unexpectedly, we also found extensive proliferation of both KLRG1− and KLRG1+ CD8+ T cells in the marginal zone and red pulp, which ceases prior to the final KLRG1Hi CXCR3Lo stage. Our findings highlight the notion of an extrafollicular pathway for effector T cell generation. DOI: http://dx.doi.org/10.7554/eLife.09017.001 PMID:26244629

  12. Characterization of Human CD8 T Cell Responses in Dengue Virus-Infected Patients from India.

    Science.gov (United States)

    Chandele, Anmol; Sewatanon, Jaturong; Gunisetty, Sivaram; Singla, Mohit; Onlamoon, Nattawat; Akondy, Rama S; Kissick, Haydn Thomas; Nayak, Kaustuv; Reddy, Elluri Seetharami; Kalam, Haroon; Kumar, Dhiraj; Verma, Anil; Panda, HareKrushna; Wang, Siyu; Angkasekwinai, Nasikarn; Pattanapanyasat, Kovit; Chokephaibulkit, Kulkanya; Medigeshi, Guruprasad R; Lodha, Rakesh; Kabra, Sushil; Ahmed, Rafi; Murali-Krishna, Kaja

    2016-12-15

    Epidemiological studies suggest that India has the largest number of dengue virus infection cases worldwide. However, there is minimal information about the immunological responses in these patients. CD8 T cells are important in dengue, because they have been implicated in both protection and immunopathology. Here, we provide a detailed analysis of HLA-DR + CD38 + and HLA-DR - CD38 + effector CD8 T cell subsets in dengue patients from India and Thailand. Both CD8 T cell subsets expanded and expressed markers indicative of antigen-driven proliferation, tissue homing, and cytotoxic effector functions, with the HLA-DR + CD38 + subset being the most striking in these effector qualities. The breadth of the dengue-specific CD8 T cell response was diverse, with NS3-specific cells being the most dominant. Interestingly, only a small fraction of these activated effector CD8 T cells produced gamma interferon (IFN-γ) when stimulated with dengue virus peptide pools. Transcriptomics revealed downregulation of key molecules involved in T cell receptor (TCR) signaling. Consistent with this, the majority of these CD8 T cells remained IFN-γ unresponsive even after TCR-dependent polyclonal stimulation (anti-CD3 plus anti-CD28) but produced IFN-γ by TCR-independent polyclonal stimulation (phorbol 12-myristate 13-acetate [PMA] plus ionomycin). Thus, the vast majority of these proliferating, highly differentiated effector CD8 T cells probably acquire TCR refractoriness at the time the patient is experiencing febrile illness that leads to IFN-γ unresponsiveness. Our studies open novel avenues for understanding the mechanisms that fine-tune the balance between CD8 T cell-mediated protective versus pathological effects in dengue. Dengue is becoming a global public health concern. Although CD8 T cells have been implicated both in protection and in the cytokine-mediated immunopathology of dengue, how the balance is maintained between these opposing functions remains unknown. We

  13. Alternative pathway for the development of Vα14+ NKT cells directly from CD4-CD8- thymocytes that bypasses the CD4+CD8+ stage.

    Science.gov (United States)

    Dashtsoodol, Nyambayar; Shigeura, Tomokuni; Aihara, Minako; Ozawa, Ritsuko; Kojo, Satoshi; Harada, Michishige; Endo, Takaho A; Watanabe, Takashi; Ohara, Osamu; Taniguchi, Masaru

    2017-03-01

    Although invariant V α 14 + natural killer T cells (NKT cells) are thought to be generated from CD4 + CD8 + double-positive (DP) thymocytes, the developmental origin of CD4 - CD8 - double-negative (DN) NKT cells still remains unresolved. Here we provide definitive genetic evidence obtained, through studies of mice with DP-stage-specific ablation of expression of the gene encoding the recombinase component RAG-2 (Rag2) and by a fate-mapping approach, that supports the proposal of the existence of an alternative developmental pathway through which a fraction of DN NKT cells with strong T-helper-type-1 (T H 1)-biased and cytotoxic characteristics develop from late DN-stage thymocytes, bypassing the DP stage. These findings provide new insight into understanding of the development of NKT cells and propose a role for timing of expression of the invariant T cell antigen receptor in determining the functional properties of NKT cells.

  14. The neonatal CD8+ T cell repertoire rapidly diversifies during persistent viral infection1

    Science.gov (United States)

    Venturi, Vanessa; Nzingha, Kito; Amos, Timothy G.; Charles, Wisler C.; Dekhtiarenko, Iryna; Cicin-Sain, Luka; Davenport, Miles P.; Rudd, Brian D.

    2015-01-01

    Cytomegalovirus (CMV) is the most common congenital infection in the United States. The major target of congenital CMV is the brain, with clinical manifestations including mental retardation, vision impairment and sensorineural hearing loss. Previous reports have shown that CD8+ T cells are required to control viral replication and significant numbers of CMV-specific CD8+ T cells persist in the brain even after the initial infection has been cleared. However, the dynamics of CD8+ T cells in the brain during latency remains largely undefined. In this report, we used T cell receptor (TCR) sequencing to track the development and maintenance of neonatal clonotypes in the brain and spleen of mice during chronic infection. Given the discontinuous nature of tissue resident memory CD8+ T cells, we hypothesized that neonatal TCR clonotypes would be ‘locked-in’ the brain and persist into adulthood. Surprisingly, we found that the antigen-specific T cell repertoire in neonatal-infected mice diversified during persistent infection in both the brain and spleen, while maintaining substantial similarity between the CD8+ T cell populations in the brain and spleen in both early and late infection. However, despite the diversification of, and potential interchange between, the spleen and brain antigen-specific T cell repertoires, we observed that germline-encoded TCR clonotypes, characteristic of neonatal infection, persisted in the brain, albeit sometimes in low abundance. These results provide valuable insights into the evolution of CD8+ T cell repertoires following neonatal CMV infection and thus have important implications for the development of therapeutic strategies to control CMV in early life. PMID:26764033

  15. Phenotypic alteration of CD8+ T cells in chronic lymphocytic leukemia is associated with epigenetic reprogramming.

    Science.gov (United States)

    Wu, Jiazhu; Xu, Xiaojing; Lee, Eun-Joon; Shull, Austin Y; Pei, Lirong; Awan, Farrukh; Wang, Xiaoling; Choi, Jeong-Hyeon; Deng, Libin; Xin, Hong-Bo; Zhong, Wenxun; Liang, Jinhua; Miao, Yi; Wu, Yujie; Fan, Lei; Li, Jianyong; Xu, Wei; Shi, Huidong

    2016-06-28

    Immunosuppression is a prevalent clinical feature in chronic lymphocytic leukemia (CLL) patients, with many patients demonstrating increased susceptibility to infections as well as increased failure of an antitumor immune response. However, much is currently not understood regarding the precise mechanisms that attribute to this immunosuppressive phenotype in CLL. To provide further clarity to this particular phenomenon, we analyzed the T-cell profile of CLL patient samples within a large cohort and observed that patients with an inverted CD4/CD8 ratio had a shorter time to first treatment as well as overall survival. These observations coincided with higher expression of the immune checkpoint receptor PD-1 in CLL patient CD8+ T cells when compared to age-matched healthy donors. Interestingly, we discovered that increased PD-1 expression in CD8+ T cells corresponds with decreased DNA methylation levels in a distal upstream locus of the PD-1 gene PDCD1. Further analysis using luciferase reporter assays suggests that the identified PDCD1 distal upstream region acts as an enhancer for PDCD1 transcription and this region becomes demethylated during activation of naïve CD8+ T cells by anti-CD3/anti-CD28 antibodies and IL2. Finally, we conducted a genome-wide DNA methylation analysis comparing CD8+ T cells from CLL patients against healthy donors and identified additional differentially methylated genes with known immune regulatory functions including CCR6 and KLRG1. Taken together, our findings reveal the occurrence of epigenetic reprogramming taking place within CLL patient CD8+ T cells and highlight the potential mechanism of how immunosuppression is accomplished in CLL.

  16. A G-protein-coupled chemokine receptor: A putative insertion site for a multi-pathogen recombinant capripoxvirus vaccine strategy.

    Science.gov (United States)

    Cêtre-Sossah, Catherine; Dickmu, Simon; Kwiatek, Olivier; Albina, Emmanuel

    2017-09-01

    Capripoxviruses (CaPVs) have been shown to be ideal viral vectors for the development of recombinant multivalent vaccines to enable delivery of immunogenic genes from ruminant pathogens. So far, the viral thymidine kinase (TK) gene is the only gene used to generate recombinants. A putative non-essential gene encoding a G-protein-coupled chemokine receptor subfamily homologue (GPCR) was targeted as an additional insertion site. Peste des petits ruminants (PPR) was chosen as a disease model. A new recombinant CaPV expressing the viral attachment hemagglutinin (H) of the PPR virus (PPRV) in the GPCR insertion site (rKS1-HPPR-GPCR) was generated in the backbone North African isolate KS1 strain of lumpy skin disease virus (LSDV). Comparison with the recombinant CaPV expressing the H of PPRV in the TK gene (rKS1-HPPR-TK) shown to induce protection against both PPR and LSD in both sheep and goats was assessed. The suitability of the GPCR gene to be a putative additional insertion site in the CaPV genome is evaluated and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Chemokine CCL2 and its receptor CCR2 in the dorsal root ganglion contribute to oxaliplatin-induced mechanical hypersensitivity.

    Science.gov (United States)

    Illias, A M; Gist, A C; Zhang, H; Kosturakis, A K; Dougherty, P M

    2018-03-15

    Activation of innate immune mechanisms within the dorsal root ganglion (DRG) and spinal dorsal horn has been shown to play a key role in the development of neuropathic pain including paclitaxel-related chemotherapy-induced peripheral neuropathy (CIPN). Here we tested whether similar mechanisms are generalizable to oxaliplatin-induced CIPN. After a single intraperitoneal injection of 3mg/kg oxaliplatin, mechanical withdrawal threshold and the expression of C-C chemokine ligand 2 (CCL2) and its receptor, CCR2 in the DRG were measured by behavioral testing and immunohistochemical (IHC) staining, respectively. Mechanical responsiveness increased from the first day after oxaliplatin injection and persisted until day 15, the last day of this experiment. IHC showed that the expression of CCL2/CCR2 started to increase by 4hrs after oxaliplatin treatment, was significantly increased at day 4, and then both signals became normalized by day15. Co-treatment with intrathecal anti-CCL2 antibodies prevented the development of oxaliplatin-induced mechanical hyper-responsiveness, and transiently reversed established hyperalgesia when given 1 week after chemotherapy. This is the first study to demonstrate CCL2/CCR2 signaling in a model of oxaliplatin-related CIPN; and it further shows that blocking of this signal can attenuate the development of oxaliplatin-induced mechanical hyperalgesia. Activation of innate immune mechanisms may therefore be a generalized basis for CIPN irrespective of the specific class of agent.

  18. Role of the chemokine receptors CCR1, CCR2 and CCR4 in the pathogenesis of experimental dengue infection in mice.

    Directory of Open Access Journals (Sweden)

    Rodrigo Guabiraba

    Full Text Available Dengue virus (DENV, a mosquito-borne flavivirus, is a public health problem in many tropical countries. Recent clinical data have shown an association between levels of different chemokines in plasma and severity of dengue. We evaluated the role of CC chemokine receptors CCR1, CCR2 and CCR4 in an experimental model of DENV-2 infection in mice. Infection of mice induced evident clinical disease and tissue damage, including thrombocytopenia, hemoconcentration, lymphopenia, increased levels of transaminases and pro-inflammatory cytokines, and lethality in WT mice. Importantly, infected WT mice presented increased levels of chemokines CCL2/JE, CCL3/MIP-1α and CCL5/RANTES in spleen and liver. CCR1⁻/⁻ mice had a mild phenotype with disease presentation and lethality similar to those of WT mice. In CCR2⁻/⁻ mice, lethality, liver damage, levels of IL-6 and IFN-γ, and leukocyte activation were attenuated. However, thrombocytopenia, hemoconcentration and systemic TNF-α levels were similar to infected WT mice. Infection enhanced levels of CCL17/TARC, a CCR4 ligand. In CCR4⁻/⁻ mice, lethality, tissue injury and systemic inflammation were markedly decreased. Despite differences in disease presentation in CCR-deficient mice, there was no significant difference in viral load. In conclusion, activation of chemokine receptors has discrete roles in the pathogenesis of dengue infection. These studies suggest that the chemokine storm that follows severe primary dengue infection associates mostly to development of disease rather than protection.

  19. Similar chemokine receptor profiles in lymphomas with central nervous system involvement - possible biomarkers for patient selection for central nervous system prophylaxis, a retrospective study.

    Science.gov (United States)

    Lemma, Siria A; Pasanen, Anna Kaisa; Haapasaari, Kirsi-Maria; Sippola, Antti; Sormunen, Raija; Soini, Ylermi; Jantunen, Esa; Koivunen, Petri; Salokorpi, Niina; Bloigu, Risto; Turpeenniemi-Hujanen, Taina; Kuittinen, Outi

    2016-05-01

    Central nervous system (CNS) relapse occurs in around 5% of diffuse large B-cell lymphoma (DLBCL) cases. No biomarkers to identify high-risk patients have been discovered. We evaluated the expression of lymphocyte-guiding chemokine receptors in systemic and CNS lymphomas. Immunohistochemical staining for CXCR4, CXCR5, CCR7, CXCL12, and CXCL13 was performed on 89 tissue samples, including cases of primary central nervous system lymphoma (PCNSL), secondary CNS lymphoma (sCNSL), and systemic DLBCL. Also, 10 reactive lymph node samples were included. Immunoelectron microscopy was performed on two PCNSLs, one sCNSL, one systemic DLBCL, and one reactive lymph node samples, and staining was performed for CXCR4, CXCR5, CXCL12, and CXCL13. Chi-square test was used to determine correlations between clinical parameters, diagnostic groups, and chemokine receptor expression. Strong nuclear CXCR4 positivity correlated with systemic DLBCL, whereas strong cytoplasmic CXCR5 positivity correlated with CNS involvement (P = 0.003 and P = 0.039). Immunoelectron microscopy revealed a nuclear CXCR4 staining in reactive lymph node, compared with cytoplasmic and membranous localization seen in CNS lymphomas. We found that CNS lymphoma presented a chemokine receptor profile different from systemic disease. Our findings give new information on the CNS tropism of DLBCL and, if confirmed, may contribute to more effective targeting of CNS prophylaxis among patients with DLBCL. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Gliadin induces an increase in intestinal permeability and zonulin release by binding to the chemokine receptor CXCR3.

    Science.gov (United States)

    Lammers, Karen M; Lu, Ruliang; Brownley, Julie; Lu, Bao; Gerard, Craig; Thomas, Karen; Rallabhandi, Prasad; Shea-Donohue, Terez; Tamiz, Amir; Alkan, Sefik; Netzel-Arnett, Sarah; Antalis, Toni; Vogel, Stefanie N; Fasano, Alessio

    2008-07-01

    Celiac disease is an immune-mediated enteropathy triggered by gliadin, a component of the grain protein gluten. Gliadin induces an MyD88-dependent zonulin release that leads to increased intestinal permeability, a postulated early element in the pathogenesis of celiac disease. We aimed to establish the molecular basis of gliadin interaction with intestinal mucosa leading to intestinal barrier impairment. Alpha-gliadin affinity column was loaded with intestinal mucosal membrane lysates to identify the putative gliadin-binding moiety. In vitro experiments with chemokine receptor CXCR3 transfectants were performed to confirm binding of gliadin and/or 26 overlapping 20mer alpha-gliadin synthetic peptides to the receptor. CXCR3 protein and gene expression were studied in intestinal epithelial cell lines and human biopsy specimens. Gliadin-CXCR3 interaction was further analyzed by immunofluorescence microscopy, laser capture microscopy, real-time reverse-transcription polymerase chain reaction, and immunoprecipitation/Western blot analysis. Ex vivo experiments were performed using C57BL/6 wild-type and CXCR3(-/-) mouse small intestines to measure intestinal permeability and zonulin release. Affinity column and colocalization experiments showed that gliadin binds to CXCR3 and that at least 2 alpha-gliadin 20mer synthetic peptides are involved in this binding. CXCR3 is expressed in mouse and human intestinal epithelia and lamina propria. Mucosal CXCR3 expression was elevated in active celiac disease but returned to baseline levels following implementation of a gluten-free diet. Gliadin induced physical association between CXCR3 and MyD88 in enterocytes. Gliadin increased zonulin release and intestinal permeability in wild-type but not CXCR3(-/-) mouse small intestine. Gliadin binds to CXCR3 and leads to MyD88-dependent zonulin release and increased intestinal permeability.

  1. Expression, purification, crystallization and preliminary X-ray diffraction analysis of rhesus macaque CD8αα homodimer

    International Nuclear Information System (INIS)

    Zong, Lili; Chen, Yong; Yan, Jinghua; Zhang, Jianhua

    2010-01-01

    CD8α exodomain protein, a crucial immune-system factor in rhesus macaque (M. mulatta), one of the best animal models for vaccine design, was assembled and crystallized. The full structure data will contribute to future studies of immune responses in rhesus macaques. As a T-cell co-receptor, CD8 binds to MHC class I molecules and plays a pivotal role in the activation of cytotoxic T lymphocytes. To date, structures of CD8 have been solved for two different mammals: human and mouse. The infection of rhesus macaques (Macaca mulatta) by simian immunodeficiency virus (SIV) is the best animal model for studying HIV. In this study, the rhesus macaque CD8 (rCD8) αα homodimer was obtained and rCD8α exodomain protein crystals were successfully obtained for further structural analysis. Diffraction data were collected to a resolution of 2.4 Å. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 46.52, b = 56.28, c = 82.40 Å. These data will facilitate further studies on the structural differences between these CD8 structures and the cellular immune responses of rhesus macaque

  2. Influence of the CCR2-V64I Polymorphism on Human Immunodeficiency Virus Type 1 Coreceptor Activity and on Chemokine Receptor Function of CCR2b, CCR3, CCR5, and CXCR4

    OpenAIRE

    Lee, Benhur; Doranz, Benjamin J.; Rana, Shalini; Yi, Yanji; Mellado, Mario; Frade, Jose M. R.; Martinez-A., Carlos; O’Brien, Stephen J.; Dean, Michael; Collman, Ronald G.; Doms, Robert W.

    1998-01-01

    The chemokine receptors CCR5 and CXCR4 are used by human immunodeficiency virus type 1 (HIV-1) in conjunction with CD4 to infect cells. In addition, some virus strains can use alternative chemokine receptors, including CCR2b and CCR3, for infection. A polymorphism in CCR2 (CCR2-V64I) is associated with a 2- to 4-year delay in the progression to AIDS. To investigate the mechanism of this protective effect, we studied the expression of CCR2b and CCR2b-V64I, their chemokine and HIV-1 coreceptor ...

  3. cAMP-responsive element modulator α (CREMα) trans-represses the transmembrane glycoprotein CD8 and contributes to the generation of CD3+CD4-CD8- T cells in health and disease.

    Science.gov (United States)

    Hedrich, Christian M; Rauen, Thomas; Crispin, Jose C; Koga, Tomohiro; Ioannidis, Christina; Zajdel, Melissa; Kyttaris, Vasileios C; Tsokos, George C

    2013-11-01

    T cell receptor-αβ(+) CD3(+)CD4(-)CD8(-) "double-negative" T cells are expanded in the peripheral blood of patients with systemic lupus erythematosus and autoimmune lymphoproliferative syndrome. In both disorders, double-negative T cells infiltrate tissues, induce immunoglobulin production, and secrete proinflammatory cytokines. Double-negative T cells derive from CD8(+) T cells through down-regulation of CD8 surface co-receptors. However, the molecular mechanisms orchestrating this process remain unclear. Here, we demonstrate that the transcription factor cAMP-responsive element modulator α (CREMα), which is expressed at increased levels in T cells from systemic lupus erythematosus patients, contributes to transcriptional silencing of CD8A and CD8B. We provide the first evidence that CREMα trans-represses a regulatory element 5' of the CD8B gene. Therefore, CREMα represents a promising candidate in the search for biomarkers and treatment options in diseases in which double-negative T cells contribute to the pathogenesis.

  4. Notch signaling pathway dampens tumor-infiltrating CD8+T cells activity in patients with colorectal carcinoma.

    Science.gov (United States)

    Yu, Weifeng; Wang, Yanjun; Guo, Peng

    2018-01-01

    CD8 + T cells play critical role in controlling the metastasis and prognosis of cancer. Controversy remains as to the contribution of Notch signaling pathway in modulation of CD8 + T cells activity and development of tumorigenesis. Thus, the aim of the current study was to investigate the immunoregulatory role of Notch signaling pathway to peripheral and tumor-infiltrating CD8 + T cells in patients with colorectal carcinoma. A total of 46 patients with colorectal carcinoma and 20 health individuals were enrolled, and CD8 + T cells were purified from both peripheral bloods and carcinoma specimens. Cytolytic and noncytolytic functions of CD8 + T cells in response to Notch signaling inhibition were evaluated by measurements of lactate dehydrogenase release and proinflammatory cytokines production in both direct and indirect contact co-culture system to target HT29 cells. Cellular proliferation and inhibitory receptors expression in CD8 + T cells were also assessed by CCK-8 method and flow cytometry. There was no remarkable difference in percentage of CD8 + T cells between healthy individuals and patients with colorectal carcinoma. Notch1/2 and Hes1/5 mRNAs were elevated expressed in tumor-infiltrating CD8 + T cells in patients with colorectal carcinoma, however, did not correlated with tumor differentiation or stages. CD8 + T cells from healthy individuals presented stronger cytotoxicity, which was not affected by Notch signaling inhibitor. Inhibition of Notch signaling pathway not only promoted cytotoxicity of tumor-infiltrating CD8 + T cells, but also enhanced proinflammatory cytokines (including IFN-γ, TNF-α, IL-1β, IL-6, and IL-8) production by CD8 + T cells from patients with colorectal carcinoma. This process was accompanied by decreased expression of PD-1 in CD8 + T cells without influencing cellular proliferation. Our results indicated a potential immunosuppressive property of Notch signaling pathway, which dampened both cytolytic and noncytolytic functions

  5. The role of CD8+ T cells during allograft rejection

    Directory of Open Access Journals (Sweden)

    V. Bueno

    2002-11-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  6. NADPH oxidase deficiency underlies dysfunction of aged CD8+ Tregs

    Science.gov (United States)

    Wen, Zhenke; Shimojima, Yasuhiro; Shirai, Tsuyoshi; Li, Yinyin; Ju, Jihang; Yang, Zhen; Tian, Lu; Goronzy, Jörg J.

    2016-01-01

    Immune aging results in progressive loss of both protective immunity and T cell–mediated suppression, thereby conferring susceptibility to a combination of immunodeficiency and chronic inflammatory disease. Here, we determined that older individuals fail to generate immunosuppressive CD8+CCR7+ Tregs, a defect that is even more pronounced in the age-related vasculitic syndrome giant cell arteritis. In young, healthy individuals, CD8+CCR7+ Tregs are localized in T cell zones of secondary lymphoid organs, suppress activation and expansion of CD4 T cells by inhibiting the phosphorylation of membrane-proximal signaling molecules, and effectively inhibit proliferative expansion of CD4 T cells in vitro and in vivo. We identified deficiency of NADPH oxidase 2 (NOX2) as the molecular underpinning of CD8 Treg failure in the older individuals and in patients with giant cell arteritis. CD8 Tregs suppress by releasing exosomes that carry preassembled NOX2 membrane clusters and are taken up by CD4 T cells. Overexpression of NOX2 in aged CD8 Tregs promptly restored suppressive function. Together, our data support NOX2 as a critical component of the suppressive machinery of CD8 Tregs and suggest that repairing NOX2 deficiency in these cells may protect older individuals from tissue-destructive inflammatory disease, such as large-vessel vasculitis. PMID:27088800

  7. Priming by chemokines restricts lateral mobility of the adhesion receptor LFA-1 and restores adhesion to ICAM-1 nano-aggregates on human mature dendritic cells.

    Directory of Open Access Journals (Sweden)

    Kyra J E Borgman

    Full Text Available LFA-1 is a leukocyte specific β2 integrin that plays a major role in regulating adhesion and migration of different immune cells. Recent data suggest that LFA-1 on mature dendritic cells (mDCs may function as a chemokine-inducible anchor during homing of DCs through the afferent lymphatics into the lymph nodes, by transiently switching its molecular conformational state. However, the role of LFA-1 mobility in this process is not yet known, despite that the importance of lateral organization and dynamics for LFA-1-mediated adhesion regulation is broadly recognized. Using single particle tracking approaches we here show that LFA-1 exhibits higher mobility on resting mDCs compared to monocytes. Lymphoid chemokine CCL21 stimulation of the LFA-1 high affinity state on mDCs, led to a significant reduction of mobility and an increase on the fraction of stationary receptors, consistent with re-activation of the receptor. Addition of soluble monomeric ICAM-1 in the presence of CCL21 did not alter the diffusion profile of LFA-1 while soluble ICAM-1 nano-aggregates in the presence of CCL21 further reduced LFA-1 mobility and readily bound to the receptor. Overall, our results emphasize the importance of LFA-1 lateral mobility across the membrane on the regulation of integrin activation and its function as adhesion receptor. Importantly, our data show that chemokines alone are not sufficient to trigger the high affinity state of the integrin based on the strict definition that affinity refers to the adhesion capacity of a single receptor to its ligand in solution. Instead our data indicate that nanoclustering of the receptor, induced by multi-ligand binding, is required to maintain stable cell adhesion once LFA-1 high affinity state is transiently triggered by inside-out signals.

  8. Structure-Activity Relationships and Identification of Optmized CC-Chemokine Receptor CCR1, 5, and 8 Metal-Ion Chelators

    DEFF Research Database (Denmark)

    Chalikiopoulos, Alexander; Thiele, Stefanie; Malmgaard-Clausen, Mikkel

    2013-01-01

    Chemokine receptors are involved in trafficking of leukocytes and represent targets for autoimmune conditions, inflammatory diseases, viral infections, and cancer. We recently published CCR1, CCR8, and CCR5 agonists and positive modulators based on a three metal-ion chelator series: 2,2'-bipyridine...... better accommodated in the receptors than polar groups. The new analog brominated terpyridine (29) resulted in the highest chelator potencies observed so far CCR1 (EC50: 0.49 μM) and CCR8 (EC50: 0.28 μM). Furthermore, we identified the first selective CCR5 agonist chelator, meta dithiomethylated...

  9. Identification of Zika virus epitopes reveals immunodominant and protective roles for dengue virus cross-reactive CD8+T cells.

    Science.gov (United States)

    Wen, Jinsheng; Tang, William Weihao; Sheets, Nicholas; Ellison, Julia; Sette, Alessandro; Kim, Kenneth; Shresta, Sujan

    2017-03-13

    CD8 + T cells play an important role in controlling Flavivirus infection, including Zika virus (ZIKV). Here, we have identified 25 HLA-B*0702-restricted epitopes and 1 HLA-A*0101-restricted epitope using interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) and intracellular cytokine staining (ICS) in ZIKV-infected IFN-α/β receptor-deficient HLA transgenic mice. The cross-reactivity of ZIKV epitopes to dengue virus (DENV) was tested using IFN-γ-ELISPOT and IFN-γ-ICS on CD8 + T cells from DENV-infected mice, and five cross-reactive HLA-B*0702-binding peptides were identified by both assays. ZIKV/DENV cross-reactive CD8 + T cells in DENV-immune mice expanded post ZIKV challenge and dominated in the subsequent CD8 + T cell response. ZIKV challenge following immunization of mice with ZIKV-specific and ZIKV/DENV cross-reactive epitopes elicited CD8 + T cell responses that reduced infectious ZIKV levels, and CD8 + T cell depletions confirmed that CD8 + T cells mediated this protection. These results identify ZIKV-specific and ZIKV/DENV cross-reactive epitopes and demonstrate both an altered immunodominance pattern in the DENV-immune setting relative to naive, as well as a protective role for epitope-specific CD8 + T cells against ZIKV. These results have important implications for ZIKV vaccine development and provide a mouse model for evaluating anti-ZIKV CD8 + T cell responses of human relevance.

  10. Interleukin-7 augments CD8+T cells function and promotes viral clearance in chronic hepatitis C virus infection.

    Science.gov (United States)

    Hou, Huanrong; Kang, Yi; Zeng, Yanli; Li, Yukui; Shang, Jia

    2018-02-01

    Interleukin (IL)-7 is a potent proliferation, activation, and survival cytokine for CD8 + T cells to improve viral and tumor specific CD8 + T cell responses. However, the role of IL-7 in regulation of dysfunctional hepatitis C virus (HCV)-specific CD8 + T cells was not fully elucidated. Thus, a total of 53 patients with chronic hepatitis C and 24 healthy individuals were enrolled in the current study. Serum IL-7 and its receptor α chain CD127 expression was measured. The modulatory function of IL-7 to CD8 + T cells was investigated in both direct and indirect contact co-culture with HCVcc-infected Huh7.5 cells. Both serum IL-7 and CD127 expression on CD8 + T cells was significantly reduced in chronic HCV-infected patients, which was negatively correlated with HCV RNA. Stimulation of IL-7 promoted both cytotoxicity and cytokines (interferon-γ, tumor necrosis factor-α, and IL-2) production of CD8 + T cells from patients with chronic hepatitis C. Moreover, IL-7 increased proliferation of CD8 + T cells, while downregulated a critical repressor of cytokine signaling, suppressor of cytokine signaling 3 (SOCS3). The IL-7-mediated enhancement effects to CD8 + T cells were dependent on IL-6 production. The current data suggested that IL-7 induced both cytolytic and noncytolytic functions of CD8 + T cells probably via repression of SOCS3. IL-7 might be considered as one of the therapeutic candidates for treatment of chronic HCV infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Comparison of Vaccine-Induced Effector CD8 T Cell Responses Directed against Self- and Non-Self-Tumor Antigens

    DEFF Research Database (Denmark)

    Pedersen, Sara R; Sørensen, Maria R; Buus, Søren

    2013-01-01

    It is generally accepted that CD8 T cells play a major role in tumor control, yet vaccination aimed at eliciting potent CD8 T cell responses are rarely efficient in clinical trials. To try and understand why this is so, we have generated potent adenoviral vectors encoding the endogenous tumor Ags...... (TA) tyrosinase-related protein-2 (TRP-2) and glycoprotein 100 (GP100) tethered to the invariant chain (Ii). Using these vectors, we sought to characterize the self-TA-specific CD8 T cell response and compare it to that induced against non-self-Ags expressed from a similar vector platform...... construct expressing a foreign (viral) TA induced efficient tumor control. Analyzing the self-TA-specific CD8 T cells, we observed that these could be activated to produce IFN-γ and TNF-α. In addition, surface expression of phenotypic markers and inhibitory receptors, as well as in vivo cytotoxicity...

  12. NKG2D stimulation of CD8(+) T cells during priming promotes their capacity to produce cytokines in response to viral infection in mice

    NARCIS (Netherlands)

    Kavazovic, Inga; Lenartic, Maja; Jelencic, Vedrana; Jurkovic, Slaven; Lemmermann, Niels A. W.; Jonjic, Stipan; Polic, Bojan; Wensveen, Felix M.

    2017-01-01

    Natural killer group 2 member D (NKG2D) is an activating receptor that is expressed on most cytotoxic cells of the immune system, including NK cells, , and CD8(+) T cells. It is still a matter of debate whether and how NKG2D mediates priming of CD8(+) T cells in vivo, due to a lack of studies where

  13. Determination of CD4+ and CD8+ lymphocytes with the cytosphere assay: a comparative study with flow cytometry and the immunoalkaline phosphatase method

    DEFF Research Database (Denmark)

    Gernow, A; Lisse, I M; Böttiger, B

    1995-01-01

    The proportion and absolute numbers of CD4+ and CD8+ lymphocytes in peripheral blood were determined using a new manual method, the cytosphere assay (CA). This method uses small latex beads coated with monoclonal antibodies directed against the CD4 and CD8 receptors, respectively. The CA was comp...

  14. MicroRNA Expression Patterns of CD8+ T Cells in Acute and Chronic Brucellosis

    Science.gov (United States)

    Budak, Ferah; Bal, S. Haldun; Tezcan, Gulcin; Guvenc, Furkan; Akalin, E. Halis; Goral, Guher; Deniz, Gunnur

    2016-01-01

    Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis. PMID:27824867

  15. Mast-Cell-Derived TNF Amplifies CD8+ Dendritic Cell Functionality and CD8+ T Cell Priming

    Directory of Open Access Journals (Sweden)

    Jan Dudeck

    2015-10-01

    Full Text Available Mast cells are critical promoters of adaptive immunity in the contact hypersensitivity model, but the mechanism of allergen sensitization is poorly understood. Using Mcpt5-CreTNFFL/FL mice, we show here that the absence of TNF exclusively in mast cells impaired the expansion of CD8+ T cells upon sensitization and the T-cell-driven adaptive immune response to elicitation. T cells primed in the absence of mast cell TNF exhibited a diminished efficiency to transfer sensitization to naive recipients. Specifically, mast cell TNF promotes CD8+ dendritic cell (DC maturation and migration to draining lymph nodes. The peripherally released mast cell TNF further critically boosts the CD8+ T-cell-priming efficiency of CD8+ DCs, thereby linking mast cell effects on T cells to DC modulation. Collectively, our findings identify the distinct potential of mast cell TNF to amplify CD8+ DC functionality and CD8+ T-cell-dominated adaptive immunity, which may be of great importance for immunotherapy and vaccination approaches.

  16. Conformational Ensembles Explored Dynamically from Disordered Peptides Targeting Chemokine Receptor CXCR4

    Directory of Open Access Journals (Sweden)

    Marian Vincenzi

    2015-05-01

    Full Text Available This work reports on the design and the synthesis of two short linear peptides both containing a few amino acids with disorder propensity and an allylic ester group at the C-terminal end. Their structural properties were firstly analyzed by means of experimental techniques in solution such as CD and NMR methods that highlighted peptide flexibility. These results were further confirmed by MD simulations that demonstrated the ability of the peptides to assume conformational ensembles. They revealed a network of transient and dynamic H-bonds and interactions with water molecules. Binding assays with a well-known drug-target, i.e., the CXCR4 receptor, were also carried out in an attempt to verify their biological function and the possibility to use the assays to develop new specific targets for CXCR4. Moreover, our data indicate that these peptides represent useful tools for molecular recognition processes in which a flexible conformation is required in order to obtain an interaction with a specific target.

  17. Conformational ensembles explored dynamically from disordered peptides targeting chemokine receptor CXCR4.

    Science.gov (United States)

    Vincenzi, Marian; Costantini, Susan; Scala, Stefania; Tesauro, Diego; Accardo, Antonella; Leone, Marilisa; Colonna, Giovanni; Guillon, Jean; Portella, Luigi; Trotta, Anna Maria; Ronga, Luisa; Rossi, Filomena

    2015-05-28

    This work reports on the design and the synthesis of two short linear peptides both containing a few amino acids with disorder propensity and an allylic ester group at the C-terminal end. Their structural properties were firstly analyzed by means of experimental techniques in solution such as CD and NMR methods that highlighted peptide flexibility. These results were further confirmed by MD simulations that demonstrated the ability of the peptides to assume conformational ensembles. They revealed a network of transient and dynamic H-bonds and interactions with water molecules. Binding assays with a well-known drug-target, i.e., the CXCR4 receptor, were also carried out in an attempt to verify their biological function and the possibility to use the assays to develop new specific targets for CXCR4. Moreover, our data indicate that these peptides represent useful tools for molecular recognition processes in which a flexible conformation is required in order to obtain an interaction with a specific target.

  18. Expression and function of the SDF-1 chemokine receptors CXCR4 and CXCR7 during mouse limb muscle development and regeneration.

    Science.gov (United States)

    Hunger, Conny; Ödemis, Veysel; Engele, Jürgen

    2012-10-15

    The chemokine, SDF-1/CXCL12, and its receptor, CXCR4, have been implied to play major roles during limb myogenesis. This concept was recently challenged by the identification of CXCR7 as an alternative SDF-1 receptor, which can either act as a scavenger receptor, a modulator of CXCR4, or an active chemokine receptor. We have now re-examined this issue by determining whether SDF-1 would signal to C2C12 myoblasts and subsequently influence their differentiation via CXCR4 and/or CXCR7. In addition, we have analyzed CXCR7, CXCR4, and SDF-1 expression in developing and injured mouse limb muscles. We demonstrate that in undifferentiated C2C12 cells, SDF-1-dependent cell signaling and resulting inhibitory effects on myogenic differentiation are entirely mediated by CXCR4. We further demonstrate that CXCR7 expression increases in differentiating C2C12 cells, which in turn abrogates CXCR4 signaling. Moreover, consistent with the view that CXCR4 and CXCR7 control limb myogenesis in vivo by similar mechanisms, we found that CXCR4 expression is the highest in late embryonic hindlimb muscles and drops shortly after birth when secondary muscle growth terminates. Vice versa, CXCR7 expression increased perinatally and persisted into adult life. Finally, underscoring the role of the SDF-1 system in muscle regeneration, we observed that SDF-1 is continuously expressed by endomysial cells of postnatal and adult muscle fibers. Analysis of dystrophin-deficient mdx mice additionally revealed that muscle regeneration is associated with muscular re-expression of CXCR4. The apparent tight control of limb muscle development and regeneration by CXCR4 and CXCR7 points to these chemokine receptors as promising therapeutic targets for certain muscle disorders. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. A novel Cd8-cis-regulatory element preferentially directs expression in CD44hiCD62L+ CD8+ T cells and in CD8αα+ dendritic cells.

    Science.gov (United States)

    Sakaguchi, Shinya; Hombauer, Matthias; Hassan, Hammad; Tanaka, Hirokazu; Yasmin, Nighat; Naoe, Yoshinori; Bilic, Ivan; Moser, Mirjam A; Hainberger, Daniela; Mayer, Herbert; Seiser, Christian; Bergthaler, Andreas; Taniuchi, Ichiro; Ellmeier, Wilfried

    2015-04-01

    CD8 coreceptor expression is dynamically regulated during thymocyte development and is tightly controlled by the activity of at least 5 different cis-regulatory elements. Despite the detailed characterization of the Cd8 loci, the regulation of the complex expression pattern of CD8 cannot be fully explained by the activity of the known Cd8 enhancers. In this study, we revisited the Cd8ab gene complex with bioinformatics and transgenic reporter gene expression approaches to search for additional Cd8 cis-regulatory elements. This led to the identification of an ECR (ECR-4), which in transgenic reporter gene expression assays, directed expression preferentially in CD44(hi)CD62L(+) CD8(+) T cells, including innate-like CD8(+) T cells. ECR-4, designated as Cd8 enhancer E8VI, was bound by Runx/CBFβ complexes and Bcl11b, indicating that E8VI is part of the cis-regulatory network that recruits transcription factors to the Cd8ab gene complex in CD8(+) T cells. Transgenic reporter expression was maintained in LCMV-specific CD8(+) T cells upon infection, although short-term, in vitro activation led to a down-regulation of E8VI activity. Finally, E8VI directed transgene expression also in CD8αα(+) DCs but not in CD8αα-expressing IELs. Taken together, we have identified a novel Cd8 enhancer that directs expression in CD44(hi)CD62L(+) CD8(+) T cells, including innate-like and antigen-specific effector/memory CD8(+) T cells and in CD8αα(+) DCs, and thus, our data provide further insight into the cis-regulatory networks that control CD8 expression. © Society for Leukocyte Biology.

  20. Capripoxvirus G-protein-coupled chemokine receptor: a host-range gene suitable for virus animal origin discrimination.

    Science.gov (United States)

    Le Goff, Christian; Lamien, Charles Euloge; Fakhfakh, Emna; Chadeyras, Amélie; Aba-Adulugba, Elexpeter; Libeau, Geneviève; Tuppurainen, Eeva; Wallace, David B; Adam, Tajelser; Silber, Roland; Gulyaz, Vely; Madani, Hafsa; Caufour, Philippe; Hammami, Salah; Diallo, Adama; Albina, Emmanuel

    2009-08-01

    The genus Capripoxvirus within the family Poxviridae comprises three closely related viruses, namely goat pox, sheep pox and lumpy skin disease viruses. This nomenclature is based on the animal species from which the virus was first isolated, respectively, goat, sheep and cattle. Since capripoxviruses are serologically identical, their specific identification relies exclusively on the use of molecular tools. We describe here the suitability of the G-protein-coupled chemokine receptor (GPCR) gene for use in host-range grouping of capripoxviruses. The analysis of 58 capripoxviruses showed three tight genetic clusters consisting of goat pox, sheep pox and lumpy skin disease viruses. However, a few discrepancies exist with the classical virus-host origin nomenclature: a virus isolated from sheep is grouped in the goat poxvirus clade and vice versa. Intra-group diversity was further observed for the goat pox and lumpy skin disease virus isolates. Despite the presence of nine vaccine strains, no genetic determinants of virulence were identified on the GPCR gene. For sheep poxviruses, the addition or deletion of 21 nucleic acids (7 aa) was consistently observed in the 5' terminal part of the gene. Specific signatures for each cluster were also identified. Prediction of the capripoxvirus GPCR topology, and its comparison with other known mammalian GPCRs and viral homologues, revealed not only a classical GPCR profile in the last three-quarters of the protein but also unique features such as a longer N-terminal end with a proximal hydrophobic alpha-helix and a shorter serine-rich C-tail.

  1. Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling and Apoptosis: Implications for Human Immunodeficiency Virus Type 1-Associated Dementia

    Science.gov (United States)

    Zheng, Jialin; Ghorpade, Anuja; Niemann, Douglas; Cotter, Robin L.; Thylin, Michael R.; Epstein, Leon; Swartz, Jennifer M.; Shepard, Robin B.; Liu, Xiaojuan; Nukuna, Adeline; Gendelman, Howard E.

    1999-01-01

    Chemokine receptors pivotal for human immunodeficiency virus type 1 (HIV-1) infection in lymphocytes and macrophages (CCR3, CCR5, and CXCR4) are expressed on neural cells (microglia, astrocytes, and/or neurons). It is these cells which are damaged during progressive HIV-1 infection of the central nervous system. We theorize that viral coreceptors could effect neural cell damage during HIV-1-associated dementia (HAD) without simultaneously affecting viral replication. To these ends, we studied the ability of diverse viral strains to affect intracellular signaling and apoptosis of neurons, astrocytes, and monocyte-derived macrophages. Inhibition of cyclic AMP, activation of inositol 1,4,5-trisphosphate, and apoptosis were induced by diverse HIV-1 strains, principally in neurons. Virions from T-cell-tropic (T-tropic) strains (MN, IIIB, and Lai) produced the most significant alterations in signaling of neurons and astrocytes. The HIV-1 envelope glycoprotein, gp120, induced markedly less neural damage than purified virions. Macrophage-tropic (M-tropic) strains (ADA, JR-FL, Bal, MS-CSF, and DJV) produced the least neural damage, while 89.6, a dual-tropic HIV-1 strain, elicited intermediate neural cell damage. All T-tropic strain-mediated neuronal impairments were blocked by the CXCR4 antibody, 12G5. In contrast, the M-tropic strains were only partially blocked by 12G5. CXCR4-mediated neuronal apoptosis was confirmed in pure populations of rat cerebellar granule neurons and was blocked by HA1004, an inhibitor of calcium/calmodulin-dependent protein kinase II, protein kinase A, and protein kinase C. Taken together, these results suggest that progeny HIV-1 virions can influence neuronal signal transduction and apoptosis. This process occurs, in part, through CXCR4 and is independent of CD4 binding. T-tropic viruses that traffic in and out of the brain during progressive HIV-1 disease may play an important role in HAD neuropathogenesis. PMID:10482576

  2. Effect of chemokine receptor CXCR4 on hypoxia-induced pulmonary hypertension and vascular remodeling in rats

    Directory of Open Access Journals (Sweden)

    Hales Charles A

    2011-02-01

    Full Text Available Abstract Background CXCR4 is the receptor for chemokine CXCL12 and reportedly plays an important role in systemic vascular repair and remodeling, but the role of CXCR4 in development of pulmonary hypertension and vascular remodeling has not been fully understood. Methods In this study we investigated the role of CXCR4 in the development of pulmonary hypertension and vascular remodeling by using a CXCR4 inhibitor AMD3100 and by electroporation of CXCR4 shRNA into bone marrow cells and then transplantation of the bone marrow cells into rats. Results We found that the CXCR4 inhibitor significantly decreased chronic hypoxia-induced pulmonary hypertension and vascular remodeling in rats and, most importantly, we found that the rats that were transplanted with the bone marrow cells electroporated with CXCR4 shRNA had significantly lower mean pulmonary pressure (mPAP, ratio of right ventricular weight to left ventricular plus septal weight (RV/(LV+S and wall thickness of pulmonary artery induced by chronic hypoxia as compared with control rats. Conclusions The hypothesis that CXCR4 is critical in hypoxic pulmonary hypertension in rats has been demonstrated. The present study not only has shown an inhibitory effect caused by systemic inhibition of CXCR4 activity on pulmonary hypertension, but more importantly also has revealed that specific inhibition of the CXCR4 in bone marrow cells can reduce pulmonary hypertension and vascular remodeling via decreasing bone marrow derived cell recruitment to the lung in hypoxia. This study suggests a novel therapeutic approach for pulmonary hypertension by inhibiting bone marrow derived cell recruitment.

  3. Relation of circulating concentrations of chemokine receptor CCR5 ligands to C-peptide, proinsulin and HbA1c and disease progression in type 1 diabetes

    DEFF Research Database (Denmark)

    Pfleger, C.; Kaas, A.; Hansen, L.

    2008-01-01

    Th1 related chemokines CCL3 and CCL5 and Th2 related CCL4 as ligands of the receptor CCR5 contribute to disease development in animal models of type 1 diabetes. In humans, no data are available addressing the role of these chemokines regarding disease progression and remission. We investigated...... longitudinally circulating concentrations of CCR5 ligands of 256 newly diagnosed patients with type 1 diabetes. CCR5 ligands were differentially associated with beta-cell function and clinical remission. CCL5 was decreased in remitters and positively associated with HbA1c suggestive of a Th1 associated...... of CCR5 by therapeutic agents such as maraviroc may provide a new therapeutic target to ameliorate disease progression in type 1 diabetes. (C) 2008 Elsevier Inc. All rights reserved Udgivelsesdato: 2008/7...

  4. Relation of circulating concentrations of chemokine receptor CCR5 ligands to C-peptide, proinsulin and HbA1c and disease progression in type 1 diabetes

    DEFF Research Database (Denmark)

    Pfleger, C; Kaas, A; Hansen, L

    2008-01-01

    Th1 related chemokines CCL3 and CCL5 and Th2 related CCL4 as ligands of the receptor CCR5 contribute to disease development in animal models of type 1 diabetes. In humans, no data are available addressing the role of these chemokines regarding disease progression and remission. We investigated...... longitudinally circulating concentrations of CCR5 ligands of 256 newly diagnosed patients with type 1 diabetes. CCR5 ligands were differentially associated with beta-cell function and clinical remission. CCL5 was decreased in remitters and positively associated with HbA1c suggestive of a Th1 associated...... of CCR5 by therapeutic agents such as maraviroc may provide a new therapeutic target to ameliorate disease progression in type 1 diabetes....

  5. Phenotype of NK-Like CD8(+) T Cells with Innate Features in Humans and Their Relevance in Cancer Diseases

    Science.gov (United States)

    Barbarin, Alice; Cayssials, Emilie; Jacomet, Florence; Nunez, Nicolas Gonzalo; Basbous, Sara; Lefèvre, Lucie; Abdallah, Myriam; Piccirilli, Nathalie; Morin, Benjamin; Lavoue, Vincent; Catros, Véronique; Piaggio, Eliane; Herbelin, André; Gombert, Jean-Marc

    2017-01-01

    Unconventional T cells are defined by their capacity to respond to signals other than the well-known complex of peptides and major histocompatibility complex proteins. Among the burgeoning family of unconventional T cells, innate-like CD8(+) T cells in the mouse were discovered in the early 2000s. This subset of CD8(+) T cells bears a memory phenotype without having encountered a foreign antigen and can respond to innate-like IL-12 + IL-18 stimulation. Although the concept of innate memory CD8(+) T cells is now well established in mice, whether an equivalent memory NK-like T-cell population exists in humans remains under debate. We recently reported that CD8(+) T cells responding to innate-like IL-12 + IL-18 stimulation and co-expressing the transcription factor Eomesodermin (Eomes) and KIR/NKG2A membrane receptors with a memory/EMRA phenotype may represent a new, functionally distinct innate T cell subset in humans. In this review, after a summary on the known innate CD8(+) T-cell features in the mouse, we propose Eomes together with KIR/NKG2A and CD49d as a signature to standardize the identification of this innate CD8(+) T-cell subset in humans. Next, we discuss IL-4 and IL-15 involvement in the generation of innate CD8(+) T cells and particularly its possible dependency on the promyelocytic leukemia zinc-finger factor expressing iNKT cells, an innate T cell subset well documented for its susceptibility to tumor immune subversion. After that, focusing on cancer diseases, we provide new insights into the potential role of these innate CD8(+) T cells in a physiopathological context in humans. Based on empirical data obtained in cases of chronic myeloid leukemia, a myeloproliferative syndrome controlled by the immune system, and in solid tumors, we observe both the possible contribution of innate CD8(+) T cells to cancer disease control and their susceptibility to tumor immune subversion. Finally, we note that during tumor progression, innate CD8(+) T

  6. Human influenza viruses and CD8(+) T cell responses.

    Science.gov (United States)

    Grant, Emma J; Quiñones-Parra, Sergio M; Clemens, E Bridie; Kedzierska, Katherine

    2016-02-01

    Influenza A viruses (IAVs) cause significant morbidity and mortality worldwide, despite new strain-specific vaccines being available annually. As IAV-specific CD8(+) T cells promote viral control in the absence of neutralizing antibodies, and can mediate cross-reactive immunity toward distinct IAVs to drive rapid recovery from both mild and severe influenza disease, there is great interest in developing a universal T cell vaccine. However, despite detailed studies in mouse models of influenza virus infection, there is still a paucity of data on human epitope-specific CD8(+) T cell responses to IAVs. This review focuses on our current understanding of human CD8(+) T cell immunity against distinct IAVs and discusses the possibility of achieving a CD8(+) T cell mediated-vaccine that protects against multiple, distinct IAV strains across diverse human populations. We also review the importance of CD8(+) T cell immunity in individuals highly susceptible to severe influenza infection, including those hospitalised with influenza, the elderly and Indigenous populations. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Chemerin Elicits Potent Constrictor Actions via Chemokine-Like Receptor 1 (CMKLR1), not G-Protein-Coupled Receptor 1 (GPR1), in Human and Rat Vasculature.

    Science.gov (United States)

    Kennedy, Amanda J; Yang, Peiran; Read, Cai; Kuc, Rhoda E; Yang, Lucy; Taylor, Emily J A; Taylor, Colin W; Maguire, Janet J; Davenport, Anthony P

    2016-10-14

    Circulating levels of chemerin are significantly higher in hypertensive patients and positively correlate with blood pressure. Chemerin activates chemokine-like receptor 1 (CMKLR1 or ChemR23) and is proposed to activate the "orphan" G-protein-coupled receptor 1 (GPR1), which has been linked with hypertension. Our aim was to localize chemerin, CMKLR1, and GPR1 in the human vasculature and determine whether 1 or both of these receptors mediate vasoconstriction. Using immunohistochemistry and molecular biology in conduit arteries and veins and resistance vessels, we localized chemerin to endothelium, smooth muscle, and adventitia and found that CMKLR1 and GPR1 were widely expressed in smooth muscle. C9 (chemerin149-157) contracted human saphenous vein (pD 2 =7.30±0.31) and resistance arteries (pD 2 =7.05±0.54) and increased blood pressure in rats by 9.1±1.0 mm Hg at 200 nmol. Crucially, these in vitro and in vivo vascular actions were blocked by CCX832, which we confirmed to be highly selective for CMKLR1 over GPR1. C9 inhibited cAMP accumulation in human aortic smooth muscle cells and preconstricted rat aorta, consistent with the observed vasoconstrictor action. Downstream signaling was explored further and, compared to chemerin, C9 showed a bias factor=≈5000 for the G i protein pathway, suggesting that CMKLR1 exhibits biased agonism. Our data suggest that chemerin acts at CMKLR1, but not GPR1, to increase blood pressure. Chemerin has an established detrimental role in metabolic syndrome, and these direct vascular actions may contribute to hypertension, an additional risk factor for cardiovascular disease. This study provides proof of principle for the therapeutic potential of selective CMKLR1 antagonists. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  8. CCR9 Is Not Required for the Homing of Pro-inflammatory Effector T cells, but Is Crucial for Recruitment and Expansion of FoxP3+ CD8+ Tregs in the Small Intestine

    DEFF Research Database (Denmark)

    Gomez-Casado, Cristina; Joeris, Thorsten; Holmkvist, Petra

    Chemokine receptor 9 (CCR9) is required for the homeostatic recruitment of T cells to the mucosa of the small intestine. Accordingly, CCR9 has been suggested as a potential target to inhibit the recruitment of proinflammatory effector T cells (Teff) in inflammatory bowel disease (IBD). Since...... the contribution of CCR9 to the recruitment of Teff in inflammation is not entirely clear, we aimed to address this question using IFABPtOva mice. These mice express Ovalbumin (Ova) specifically in small intestinal epithelial cells, which allows triggering of acute inflammation following transfer of Ova......-specific CD8+ T cells (OT-I cells) and adjuvant treatment. Strikingly, intestinal inflammation in IFABP-tOva mice could also be triggered following transfer of CCR9-deficient OT-I cells, demonstrating that CCR9 is not required for homing of Teff cells. Interestingly, OTI cells transferred to IFABP-tOva mice...

  9. IRF9 Prevents CD8+T Cell Exhaustion in an Extrinsic Manner during Acute Lymphocytic Choriomeningitis Virus Infection.

    Science.gov (United States)

    Huber, Magdalena; Suprunenko, Tamara; Ashhurst, Thomas; Marbach, Felix; Raifer, Hartmann; Wolff, Svenja; Strecker, Thomas; Viengkhou, Barney; Jung, So Ri; Obermann, Hannah-Lena; Bauer, Stefan; Xu, Haifeng C; Lang, Philipp A; Tom, Adomati; Lang, Karl S; King, Nicholas J C; Campbell, Iain L; Hofer, Markus J

    2017-11-15

    Effective CD8 + T cell responses play an important role in determining the course of a viral infection. Overwhelming antigen exposure can result in suboptimal CD8 + T cell responses, leading to chronic infection. This altered CD8 + T cell differentiation state, termed exhaustion, is characterized by reduced effector function, upregulation of inhibitory receptors, and altered expression of transcription factors. Prevention of overwhelming antigen exposure to limit CD8 + T cell exhaustion is of significant interest for the control of chronic infection. The transcription factor interferon regulatory factor 9 (IRF9) is a component of type I interferon (IFN-I) signaling downstream of the IFN-I receptor (IFNAR). Using acute infection of mice with lymphocytic choriomeningitis virus (LCMV) strain Armstrong, we show here that IRF9 limited early LCMV replication by regulating expression of interferon-stimulated genes and IFN-I and by controlling levels of IRF7, a transcription factor essential for IFN-I production. Infection of IRF9- or IFNAR-deficient mice led to a loss of early restriction of viral replication and impaired antiviral responses in dendritic cells, resulting in CD8 + T cell exhaustion and chronic infection. Differences in the antiviral activities of IRF9- and IFNAR-deficient mice and dendritic cells provided further evidence of IRF9-independent IFN-I signaling. Thus, our findings illustrate a CD8 + T cell-extrinsic function for IRF9, as a signaling factor downstream of IFNAR, in preventing overwhelming antigen exposure resulting in CD8 + T cell exhaustion and, ultimately, chronic infection. IMPORTANCE During early viral infection, overwhelming antigen exposure can cause functional exhaustion of CD8 + T cells and lead to chronic infection. Here we show that the transcription factor interferon regulatory factor 9 (IRF9) plays a decisive role in preventing CD8 + T cell exhaustion. Using acute infection of mice with LCMV strain Armstrong, we found that IRF9

  10. Radiosensitivity of CD3-CD8+CD56+ NK cells

    Energy Technology Data Exchange (ETDEWEB)

    Vokurkova, Doris [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic); Vavrova, Jirina [University of Defence, Faculty of Military Health Sciences, Department of Radiobiology, Hradec Kralove (Czech Republic); Sinkora, Jiri [Becton Dickinson (Czech Republic); Stoklasova, Alena [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic); Blaha, Vaclav [University of Defence, Faculty of Military Health Sciences, Department of Radiobiology, Hradec Kralove (Czech Republic); Rezacova, Martina, E-mail: rezacovam@lfhk.cuni.c [Charles University in Prague, Faculty of Medicine in Hradec Kralove, Department of Medical Biochemistry, Simkova 870, 50038 Hradec Kralove 1 (Czech Republic)

    2010-10-15

    The effect of lower doses (0.5-3.0 Gy) of gamma radiation on radiosensitivity of CD3-/CD8+ NK cells subpopulation isolated from the peripheral blood of healthy volunteers was studied 48 h after the irradiation. Only a subtle increase in terms of induction of apoptosis (A+ cells), was observed in Annexin positive CD3-/CD8+ NK cells. The assessment of the relative presence of CD3{sup -}/CD8{sup +} NK cells in Annexin negative populations of lymphocytes considerably contributes to the elimination of individual variability and could be useful in biodosimetry. Living CD3-/CD8+; Annexin negative NK cells were analyzed using five-color flow cytometry 16 h after irradiation by the doses of 1-10 Gy. The study was carried out on NK cells subsets CD3-/CD8- CD16+, CD56 (dim) and CD56 (bright). NK cells characterized with their low-density expression of CD56 (dim) are more cytotoxic and express CD16. Those with high-density expression of CD56 (bright) are known for their capacity to produce cytokines following activation of monocytes but their natural cytotoxicity is low; they are classified as CD16- or CD16 (dim). A dose-depending decrease in the relative presence of CD3-/CD8+ NK cells was observed 16 h after ionizing radiation (1-10 Gy). The decrease was highly pronounced in CD56 (bright) subset of NK cells and this subpopulation was considered as the most radiosensitive one. Unfortunately, the most radiosensitive subpopulation of NK cells - CD56bright cannot be used as a biodosimetric marker due to its insufficient amount in peripheral blood.

  11. The scavenging chemokine receptor ACKR2 has a significant impact on acute mortality rate and early lesion development after traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Thomas M Woodcock

    Full Text Available The atypical chemokine receptor ACKR2 promotes resolution of acute inflammation by operating as a scavenger receptor for inflammatory CC chemokines in several experimental models of inflammatory disorders, however its role in the brain remains unclear. Based on our previous reports of increased expression of inflammatory chemokines and their corresponding receptors following traumatic brain injury (TBI, we hypothesised that ACKR2 modulates neuroinflammation following brain trauma and that its deletion exacerbates cellular inflammation and chemokine production. We demonstrate increased CCL2 and ACKR2 mRNA expression in post-mortem human brain, whereby ACKR2 mRNA levels correlated with later times post-TBI. This data is consistent with the transient upregulation of ACKR2 observed in mouse brain after closed head injury (CHI. As compared to WT animals, ACKR2-/- mice showed a higher mortality rate after CHI, while the neurological outcome in surviving mice was similar. At day 1 post-injury, ACKR2-/- mice displayed aggravated lesion volume and no differences in CCL2 expression and macrophage recruitment relative to WT mice. Reciprocal regulation of ACKR2 and CCL2 expression was explored in cultured astrocytes, which are recognized as the major source of CCL2 and also express ACKR2. ACKR2 mRNA increased as early as 2 hours after an inflammatory challenge in WT astrocytes. As expected, CCL2 expression also dramatically increased at 4 hours in WT astrocytes but was significantly lower in ACKR2-/- astrocytes, possibly indicating a co-regulation of CCL2 and ACKR2 in these cells. Conversely, in vivo, CCL2 mRNA/protein levels were increased similarly in ACKR2-/- and WT brains at 4 and 12 hours after CHI, in line with the lack of differences in cerebral macrophage recruitment and neurological recovery. In conclusion, ACKR2 is induced after TBI and has a significant impact on mortality and lesion development acutely following CHI, while its role in chemokine

  12. New insights in chemokine signaling [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Daniel F. Legler

    2018-01-01

    Full Text Available Chemokine signaling is essential for coordinated cell migration in health and disease to specifically govern cell positioning in space and time. Typically, chemokines signal through heptahelical, G protein-coupled receptors to orchestrate cell migration. Notably, chemokine receptors are highly dynamic structures and signaling efficiency largely depends on the discrete contact with the ligand. Promiscuity of both chemokines and chemokine receptors, combined with biased signaling and allosteric modulation of receptor activation, guarantees a tightly controlled recruitment and positioning of individual cells within the local environment at a given time. Here, we discuss recent insights in understanding chemokine gradient formation by atypical chemokine receptors and how typical chemokine receptors can transmit distinct signals to translate guidance cues into coordinated cell locomotion in space and time.

  13. Blimp-1–mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis

    Science.gov (United States)

    Cobb, Dustin A.; Bhadra, Rajarshi

    2016-01-01

    CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)–susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell–intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches. PMID:27481131

  14. Magnitude and kinetics of CD8+ T cell activation during hyperacute HIV infection impacts viral set point

    Science.gov (United States)

    Ndhlovu, Zaza; Kamya, Philomena; Mewalal, Nikoshia; Kløverpris, Henrik N.; Nkosi, Thandeka; Pretorius, Karyn; Laher, Faatima; Ogunshola, Funsho; Chopera, Denis; Shekhar, Karthik; Ghebremichael, Musie; Ismail, Nasreen; Moodley, Amber; Malik, Amna; Leslie, Alasdair; Goulder, Philip J.R; Buus, Søren; Chakraborty, Arup; Dong, Krista; Ndung’u, Thumbi; Walker, Bruce D.

    2015-01-01

    Summary CD8+ T cells contribute to the control of HIV, but it is not clear whether initial immune responses modulate the viral set point. We screened high-risk uninfected women twice a week for plasma HIV RNA and identified twelve hyperacute infections. Onset of viremia elicited a massive HIV-specific CD8+ T cell response, with limited bystander activation of non-HIV memory CD8+ T cells. HIV-specific CD8+ T cells secreted little interferon-γ, underwent rapid apoptosis and failed to upregulate the interleukin 7 receptor, known to be important for T cell survival. The rapidity to peak CD8+ T cell activation and the absolute magnitude of activation induced by the exponential rise in viremia were inversely correlated with set point viremia. These data indicate that rapid, high magnitude HIV-induced CD8+ T cell responses are crucial for subsequent immune control of acute infection, which has important implications for HIV vaccine design. PMID:26362266

  15. Immediate Dysfunction of Vaccine-Elicited CD8+ T Cells Primed in the Absence of CD4+ T Cells

    Science.gov (United States)

    Provine, Nicholas M.; Larocca, Rafael A.; Aid, Malika; Penaloza-MacMaster, Pablo; Badamchi-Zadeh, Alexander; Borducchi, Erica N.; Yates, Kathleen B.; Abbink, Peter; Kirilova, Marinela; Ng’ang’a, David; Bramson, Jonathan; Haining, W. Nicholas

    2016-01-01

    CD4+ T cell help is critical for optimal CD8+ T cell memory differentiation and maintenance in many experimental systems. In addition, many reports have identified reduced primary CD8+ T cell responses in the absence of CD4+ T cell help, which often coincides with reduced Ag or pathogen clearance. In this study, we demonstrate that absence of CD4+ T cells at the time of adenovirus vector immunization of mice led to immediate impairments in early CD8+ T cell functionality and differentiation. Unhelped CD8+ T cells exhibited a reduced effector phenotype, decreased ex vivo cytotoxicity, and decreased capacity to produce cytokines. This dysfunctional state was imprinted within 3 d of immunization. Unhelped CD8+ T cells expressed elevated levels of inhibitory receptors and exhibited transcriptomic exhaustion and anergy profiles by gene set enrichment analysis. Dysfunctional, impaired effector differentiation also occurred following immunization of CD4+ T cell–deficient mice with a poxvirus vector. This study demonstrates that following priming with viral vectors, CD4+ T cell help is required to promote both the expansion and acquisition of effector functions by CD8+ T cells, which is accomplished by preventing immediate dysfunction. PMID:27448585

  16. Cytomegalovirus vector expressing RAE-1γ induces enhanced anti-tumor capacity of murine CD8+T cells.

    Science.gov (United States)

    Tršan, Tihana; Vuković, Kristina; Filipović, Petra; Brizić, Ana Lesac; Lemmermann, Niels A W; Schober, Kilian; Busch, Dirk H; Britt, William J; Messerle, Martin; Krmpotić, Astrid; Jonjić, Stipan

    2017-08-01

    Designing CD8 + T-cell vaccines, which would provide protection against tumors is still considered a great challenge in immunotherapy. Here we show the robust potential of cytomegalovirus (CMV) vector expressing the NKG2D ligand RAE-1γ as CD8 + T cell-based vaccine against malignant tumors. Immunization with the CMV vector expressing RAE-1γ, delayed tumor growth or even provided complete protection against tumor challenge in both prophylactic and therapeutic settings. Moreover, a potent tumor control in mice vaccinated with this vector can be further enhanced by blocking the immune checkpoints TIGIT and PD-1. CMV vector expressing RAE-1γ potentiated expansion of KLRG1 + CD8 + T cells with enhanced effector properties. This vaccination was even more efficient in neonatal mice, resulting in the expansion and long-term maintenance of epitope-specific CD8 + T cells conferring robust resistance against tumor challenge. Our data show that immunomodulation of CD8 + T-cell responses promoted by herpesvirus expressing a ligand for NKG2D receptor can provide a powerful platform for the prevention and treatment of CD8 + T-cell sensitive tumors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Microbial corruption of the chemokine system: an expanding paradigm.

    Science.gov (United States)

    Pease, J E; Murphy, P M

    1998-06-01

    The chemokine signaling system includes more than 40 secreted pro-inflammatory peptides and 12 G protein-coupled receptors that together orchestrate specific leukocyte trafficking in the mammalian immune system, ideally for anti- microbial defense and tissue repair processes. Paradoxically and perversely, some chemokines and chemokine receptors are also promicrobial factors and facilitate infectious disease, the result of either exploitation or subversion by specific microbes. Two modes of exploitation are known: usage of cellular chemokine receptors for cell entry by intracellular pathogens, including HIV, and usage of virally-encoded chemokine receptors for host cell proliferation. Likewise, two modes of subversion are known: virally-encoded chemokine antagonists and virally-encoded chemokine scavengers. Understanding how microbes turn the tables on the chemokine system may point to new methods to prevent or treat infection, or, more generally, to treat inappropriate chemokine-mediated inflammation. Copyright 1998 Academic Press.

  18. Monocyte-derived dendritic cells are essential for CD8+ T cell activation and anti-tumor responses after local immunotherapy

    Directory of Open Access Journals (Sweden)

    Sabine eKuhn

    2015-11-01

    Full Text Available Tumors harbor several populations of dendritic cells with the ability to prime tumor-specific T cells. However, these T cells mostly fail to differentiate into armed effectors and are unable to control tumor growth. We have previously shown that treatment with immunostimulatory agents at the tumor site can activate anti-tumor immune responses, and is associated with the appearance of a population of monocyte-derived dendritic cells in the tumor and tumor-draining lymph node. Here we use dendritic cell or monocyte depletion and monocyte transfer to show that these monocyte-derived dendritic cells are critical to the activation of anti-tumor immune responses. Treatment with the immunostimulatory agents Monosodium Urate crystals and Mycobacterium smegmatis induced the accumulation of monocytes in the draining lymph node, their upregulation of CD11c and MHCII, and expression of iNOS, TNFα and IL12p40. Blocking monocyte entry into the lymph node and tumor through neutralization of the chemokine CCL2 or inhibition of Colony Stimulating Factor-1 receptor signaling prevented the generation of monocyte-derived dendritic cells, the infiltration of tumor-specific T cells into the tumor, and anti-tumor responses. In a reciprocal fashion, monocytes transferred into mice depleted of CD11c+ cells were sufficient to rescue CD8+ T cell priming in lymph node and delay tumor growth. Thus monocytes exposed to the appropriate conditions become powerful activators of tumor-specific CD8+ T cells and anti-tumor immunity.

  19. A BTLA-mediated bait-and-switch strategy permits Listeria expansion in CD8α+ DCs to promote long term T cell responses

    Science.gov (United States)

    Yang, Xuanming; Zhang, Xunmin; Sun, Yonglian; Tu, Tony; Fu, May Lynne; Miller, Mendy; Fu, Yang-Xin

    2014-01-01

    SUMMARY Listeria monocytogenes infected CD8α+ DCs in the spleen are essential for CD8+ T cell generation. CD8α+ DCs are also necessary for Listeria expansion and dissemination within the host. The mechanisms that regulate CD8α+ DCs to allow Listeria expansion are unclear. We find that activating the B and T lymphocyte attenuator (BTLA), a co-inhibitory receptor on CD8α+ DCs, suppresses, while blocking BTLA enhances both the primary and memory CD8 T cell responses against Listeria. Btla−/− mice have lower effector and memory CD8+ T cells while paradoxically also being more resistant to Listeria. Although bacterial entry into Btla−/− CD8α+ DCs is unaffected, Listeria fails to expand within these cells. BTLA signaling limits Fas/FasL-mediated suppression of Listeria expansion within CD8α+ DCs to more effectively alert adaptive immune cells. This study uncovers a BTLA-mediated strategy used by the host that permits Listeria proliferation to enable increasing T cell responses for long-term protection. PMID:25011109

  20. Toll-like receptor 2 contributes to chemokine gene expression and macrophage infiltration in the dorsal root ganglia after peripheral nerve injury

    Directory of Open Access Journals (Sweden)

    Lee Sung Joong

    2011-09-01

    Full Text Available Abstract Background We have previously reported that nerve injury-induced neuropathic pain is attenuated in toll-like receptor 2 (TLR2 knock-out mice. In these mice, inflammatory gene expression and spinal cord microglia actvation is compromised, whereas the effects in the dorsal root ganglia (DRG have not been tested. In this study, we investigated the role of TLR2 in inflammatory responses in the DRG after peripheral nerve injury. Results L5 spinal nerve transection injury induced the expression of macrophage-attracting chemokines such as CCL2/MCP-1 and CCL3/MIP-1 and subsequent macrophage infiltration in the DRG of wild-type mice. In TLR2 knock-out mice, however, the induction of chemokine expression and macrophage infiltration following nerve injury were markedly reduced. Similarly, the induction of IL-1β and TNF-α expression in the DRG by spinal nerve injury was ameliorated in TLR2 knock-out mice. The reduced inflammatory response in the DRG was accompanied by attenuation of nerve injury-induced spontaneous pain hypersensitivity in TLR2 knock-out mice. Conclusions Our data show that TLR2 contributes to nerve injury-induced proinflammatory chemokine/cytokine gene expression and macrophage infiltration in the DRG, which may have relevance in the reduced pain hypersensitivity in TLR2 knock-out mice after spinal nerve injury.

  1. Signal Integration by Akt Regulates CD8 TCell Effector and Memory Differentiation

    Science.gov (United States)

    Kim, Eui Ho; Sullivan, Jeremy A.; Plisch, Erin H.; Tejera, Melba Marie; Jatzek, Anna; Choi, Kwan Yong; Suresh, M.

    2012-01-01

    During a T cell response, the effector CTL pool contains two cellular subsets: short-lived effector cells (SLECs), a majority of which are destined for apoptosis, and the memory precursor effector cells (MPECs) that differentiate into memory cells. Understanding the mechanisms that govern the differentiation of memory CD8 T cells is of fundamental importance in the development of effective CD8 T cell-based vaccines. The strength and nature of TCR signaling along with signals delivered by cytokines like IL-2 and IL-12influence differentiation of SLECs and MPECs. A central question is, how are signals emanating from multiple receptors integrated and interpreted to define the fate of effector CTLs? Using genetic and pharmacological tools, we have identified Akt as a signal integrator that links distinct facets of CTL differentiation to the specific signaling pathways of FOXO, mTOR, and Wnt/β-catenin. Sustained Akt activation triggered by convergent extracellular signals evokes a transcription program that enhances effector functions, drives differentiation of terminal effectors, and diminishes the CTLs’ potential to survive and differentiate into memory cells. While sustained Akt activation severely impaired CD8 T cell memory and protective immunity, in vivo inhibition of Akt rescued SLECs from deletion and increased the number of memory CD8 T cells. Thus, the cumulative strength of convergent signals from signaling molecules such as TCR, costimulatory molecules, and cytokine receptors governs the magnitude of Akt activation, which in turn controls the generation of long-lived memory cells. These findings suggest that therapeutic modulation of Akt might be a strategy to augment vaccine-induced immunity. PMID:22467649

  2. Multi-scale modeling of the CD8 immune response

    Science.gov (United States)

    Barbarroux, Loic; Michel, Philippe; Adimy, Mostafa; Crauste, Fabien

    2016-06-01

    During the primary CD8 T-Cell immune response to an intracellular pathogen, CD8 T-Cells undergo exponential proliferation and continuous differentiation, acquiring cytotoxic capabilities to address the infection and memorize the corresponding antigen. After cleaning the organism, the only CD8 T-Cells left are antigen-specific memory cells whose role is to respond stronger and faster in case they are presented this very same antigen again. That is how vaccines work: a small quantity of a weakened pathogen is introduced in the organism to trigger the primary response, generating corresponding memory cells in the process, giving the organism a way to defend himself in case it encounters the same pathogen again. To investigate this process, we propose a non linear, multi-scale mathematical model of the CD8 T-Cells immune response due to vaccination using a maturity structured partial differential equation. At the intracellular scale, the level of expression of key proteins is modeled by a delay differential equation system, which gives the speeds of maturation for each cell. The population of cells is modeled by a maturity structured equation whose speeds are given by the intracellular model. We focus here on building the model, as well as its asymptotic study. Finally, we display numerical simulations showing the model can reproduce the biological dynamics of the cell population for both the primary response and the secondary responses.

  3. Global transcriptional characterization of CD8+ T cell memory.

    Science.gov (United States)

    Böttcher, Jan; Knolle, Percy A

    2015-02-01

    The differentiation of memory CD8T cells after acute infections comprises generation of functionally distinct populations that either have proliferative potential or display cytotoxic effector functions and that either recirculate into lymphoid tissues or remain tissue-resident. The development of these functionally distinct cell populations is dictated by defined signals from the microenvironment that result in a coordinated expression of a network of transcription factors, which determine the functionality of memory T cells. Distinct transcriptional regulation observed during chronic viral infection that results in generation of T cells that control viral replication in the absence of immunopathology suggests the existence of so far unappreciated functional adaptation of T cell function to the particular need during chronic infections to control infection and avoid immunopathology. Furthermore, the non-canonical generation of CD8T cell memory outside of lymphoid tissues in the liver in the absence of inflammation is correlated with a distinct transcriptional profile and indicates further complexity in the commensurate immune response to infectious pathogens that escape innate immunity. Taken together, distinct profiles of transcriptional regulation are linked to CD8T cells with different functions and provide important mechanistic insight into the continuous functional adaptation of CD8T cells to generate a commensurate immune response to infectious challenges. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Multi-scale modeling of the CD8 immune response

    Energy Technology Data Exchange (ETDEWEB)

    Barbarroux, Loic, E-mail: loic.barbarroux@doctorant.ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Michel, Philippe, E-mail: philippe.michel@ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Adimy, Mostafa, E-mail: mostafa.adimy@inria.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France); Crauste, Fabien, E-mail: crauste@math.univ-lyon1.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France)

    2016-06-08

    During the primary CD8 T-Cell immune response to an intracellular pathogen, CD8 T-Cells undergo exponential proliferation and continuous differentiation, acquiring cytotoxic capabilities to address the infection and memorize the corresponding antigen. After cleaning the organism, the only CD8 T-Cells left are antigen-specific memory cells whose role is to respond stronger and faster in case they are presented this very same antigen again. That is how vaccines work: a small quantity of a weakened pathogen is introduced in the organism to trigger the primary response, generating corresponding memory cells in the process, giving the organism a way to defend himself in case it encounters the same pathogen again. To investigate this process, we propose a non linear, multi-scale mathematical model of the CD8 T-Cells immune response due to vaccination using a maturity structured partial differential equation. At the intracellular scale, the level of expression of key proteins is modeled by a delay differential equation system, which gives the speeds of maturation for each cell. The population of cells is modeled by a maturity structured equation whose speeds are given by the intracellular model. We focus here on building the model, as well as its asymptotic study. Finally, we display numerical simulations showing the model can reproduce the biological dynamics of the cell population for both the primary response and the secondary responses.

  5. Acquired Antibody Responses against Plasmodium vivax Infection Vary with Host Genotype for Duffy Antigen Receptor for Chemokines (DARC)

    Science.gov (United States)

    Maestre, Amanda; Muskus, Carlos; Duque, Victoria; Agudelo, Olga; Liu, Pu; Takagi, Akihide; Ntumngia, Francis B.; Adams, John H.; Sim, Kim Lee; Hoffman, Stephen L.; Corradin, Giampietro; Velez, Ivan D.; Wang, Ruobing

    2010-01-01

    Background Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC) is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are ‘resistant’ to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens. Methodology/Findings We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1) and Duffy binding protein (PvDBP) varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull) were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B). The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion. Conclusion/Significance Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the

  6. Acquired antibody responses against Plasmodium vivax infection vary with host genotype for duffy antigen receptor for chemokines (DARC.

    Directory of Open Access Journals (Sweden)

    Amanda Maestre

    2010-07-01

    Full Text Available Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are 'resistant' to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens.We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1 and Duffy binding protein (PvDBP varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B. The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion.Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the primary mechanisms by which P. vivax evades

  7. Association of chemokine receptor CX3CR1 V249I and T280M polymorphisms with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    A K Yadav

    2016-01-01

    Full Text Available The chemokine fractalkine (CX3CL1 and its receptor CX3CR1 are involved in the activation of leukocytes. Two common single-nucleotide polymorphisms of the CX3CR1 gene, V249I and T280M, have been associated with reduced fractalkine signaling, leading to decreased adhesive function and leukocyte chemotaxis. We hypothesized that variation in the CX3CR1 gene could be associated with chronic kidney disease (CKD, a disease of inflammatory activation. We studied the association between CX3CR1 V249I and T280M polymorphisms, and fractalkine and highly sensitive C-reactive protein (hs-CRP levels in 123 patients with CKD and 100 healthy controls (HCs. Genotype analysis was done by polymerase chain reaction-restriction fragment length polymorphism, and fractalkine and hs-CRP levels were analyzed by enzyme-linked immunosorbent assay. MM genotype of T280M was absent in CKD patients, while in controls it was seen in 1% of the individuals. The allele frequencies in both the groups were similar (P = 0.059. Compared to HC, M280M + T280M genotype was more frequent in CKD (P = 0.041. The frequency of II genotype of V249I was 0.8% in CKD, whereas in HC, it was 2%. I249I + V249I genotype was more frequent in CKD as compared to HC (P = 0.034. No difference in allelic frequency of V249I was noted between the two groups (P = 0.061, odds ratios = 1.74, 95% confidence intervals = 0.96–3.12. Plasma fractalkine and serum hs-CRP levels were higher in CKD subjects (P = 0.004 and P 's 0.0001. No association of either genotype was found with fractalkine and hs-CRP levels. Polymorphisms at I249 and M280 genotype in CX3CR1 gene are associated with CKD; however, there was no association of fractalkine or inflammatory marker with these genotypes.

  8. A closed-tube assay for genotyping of the 32-bp deletion polymorphism in the chemokine receptor 5 (CCR5) gene

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Berg; Werge, Thomas

    2007-01-01

    We have developed a closed-tube assay for determination of the chemokine receptor type 5 (CCR5) 32-bp deletion allele, which protects against infections with HIV and modulates susceptibility to a variety of inflammatory diseases. This assay utilizes dissociation analysis of amplified products...... in the presence of Sybr Green I for allele discrimination. After having established robust conditions for the assay, we used it to genotype 590 unknown DNA samples. A blinded comparison with a procedure based upon agarose gel electrophoresis of amplified material revealed complete concordance between the two...

  9. Relationship between the chemokine receptor CCR5 and microglia in neurological disorders: consequences of targeting CCR5 on neuroinflammation, neuronal death and regeneration in a model of epilepsy.

    Science.gov (United States)

    Louboutin, Jean-Pierre; Strayer, David S

    2013-09-01

    Chemokines may play a role in leukocyte migration across the blood-brain barrier (BBB) during neuroinflammation and other neuropathological processes, such as epilepsy. The CC chemokine receptor 5 (CCR5) is a member of CC-chemokine receptor family that binds several chemokines, including CCL3 (macrophage inflammatory protein-1alpha, MIP-1alpha), CCL4 (macrophage inflammatory protein-1beta, MIP-1beta) and CCL5 (RANTES). The current review examines the relationship between CCR5 and the microglia in different neurological disorders and models of CNS injury. CCR5 expression is upregulated in different neurological diseases, where it is often immunolocalized in microglial cells. A multistep cascade couples CCR5 activation by chemokines to Ca(2+) increases in human microglia. Because changes in [Ca(2+)] (i) affect chemotaxis, secretion, and gene expression, pharmacologic modulation of this pathway may alter inflammatory and degenerative processes in the CNS. Consequently, targeting CCR5 by using CCR5 antagonists may attenuate critical aspects of neuroinflammation in different models of neurological disorders. To illustrate the interaction between CCR5 and microglia in the CNS, we used a model of excitotoxicity, and demonstrate the intimate involvement of CCR5 in neuron injury and inflammation attendant to kainic acid (KA)-induced neurotoxicity. CCR5 participates in neuronal injury caused by the excitotoxin, KA, brings inflammatory cells to the sites of KA-induced CNS injury, defines the extent of tissue loss after KA exposure and limits reparative responses. We used a SV40-derived vector carrying an interfering RNA (RNAi) that targets CCR5. Delivered directly to the bone marrow, this vector decreased CCR5 expression in circulating cells. Animals so treated showed greatly reduced expression of CCR5 and its ligands (MIP-1alpha and RANTES) in the CNS, including in the brain vasculature, decreased BBB leakage, demonstrated greater KA-stimulated neurogenesis and increased

  10. Tumor-derived exosomes induce CD8+T cell suppressors.

    Science.gov (United States)

    Maybruck, Brian T; Pfannenstiel, Lukas W; Diaz-Montero, Marcela; Gastman, Brian R

    2017-08-15

    The suppressive nature of immune cells in the tumor microenvironment plays a major role in regulating anti-tumor immune responses. Our previous work demonstrated that a soluble factor from tumor cells is able to induce a suppressor phenotype (SP) in human CD8 + T cells typified by loss of CD27/CD28 expression and acquisition of a potent suppressor function. The present study hypothesized that the soluble mechanism that is inducing the SP in CD8 + T cells are tumor-derived exosomes (TDEs). Membrane vesicles and TDEs from multiple head and neck cancer cell line's conditioned growth media were isolated by ultracentrifugation and precipitation, respectively. Human purified CD3 + CD8 + T cells were assessed for their induction of the T cell SP by flow cytometry identifying loss of CD27/CD28 expression and in vitro suppression assays. Furthermore, the T cell SP was characterized for the attenuation of IFN-γ production. To delineate exosomal proteins contributing to T cell SP, mass spectrometry was used to identify unique proteins that were present in TDEs. CRISPR/Cas9 knockout constructs were used to examine the role of one of these proteins, galectin-1. To assess the role of exosomal RNA, RNA purified from TDEs was nucleofected into CD8 + T cells followed by suppression analysis. Using fractionated conditioned growth media, factors >200 kDa induced CD8 + T cell SP, which was determined to be an exosome by mass spectrometry analysis. Multiple head and neck cancer-derived cell lines were found to secrete T cell SP-inducing exosomes. Mass spectrometry analysis revealed that an immunoregulatory protein, galectin-1 (Gal-1), was expressed in those exosomes, but not in TDEs unable to induce T cell SP. Galectin-1 knockout cells were found to be less able to induce T cell SP. Furthermore, RNA purified from the T cell SP-inducing exosomes were found to partially induce the SP when transfected into normal CD8 + T cells. For the first-time, TDEs have been identified to induce a

  11. Innate-like Cytotoxic Function of Bystander-Activated CD8+T Cells Is Associated with Liver Injury in Acute Hepatitis A.

    Science.gov (United States)

    Kim, Jihye; Chang, Dong-Yeop; Lee, Hyun Woong; Lee, Hoyoung; Kim, Jong Hoon; Sung, Pil Soo; Kim, Kyung Hwan; Hong, Seon-Hui; Kang, Wonseok; Lee, Jino; Shin, So Youn; Yu, Hee Tae; You, Sooseong; Choi, Yoon Seok; Oh, Insoo; Lee, Dong Ho; Lee, Dong Hyeon; Jung, Min Kyung; Suh, Kyung-Suk; Hwang, Shin; Kim, Won; Park, Su-Hyung; Kim, Hyung Joon; Shin, Eui-Cheol

    2018-01-16

    Acute hepatitis A (AHA) involves severe CD8 + T cell-mediated liver injury. Here we showed during AHA, CD8 + T cells specific to unrelated viruses became activated. Hepatitis A virus (HAV)-infected cells produced IL-15 that induced T cell receptor (TCR)-independent activation of memory CD8 + T cells. TCR-independent activation of non-HAV-specific CD8 + T cells were detected in patients, as indicated by NKG2D upregulation, a marker of TCR-independent T cell activation by IL-15. CD8 + T cells derived from AHA patients exerted innate-like cytotoxicity triggered by activating receptors NKG2D and NKp30 without TCR engagement. We demonstrated that the severity of liver injury in AHA patients correlated with the activation of HAV-unrelated virus-specific CD8 + T cells and the innate-like cytolytic activity of CD8 + T cells, but not the activation of HAV-specific T cells. Thus, host injury in AHA is associated with innate-like cytotoxicity of bystander-activated CD8 + T cells, a result with implications for acute viral diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Activation and exhaustion of antigen-specific CD8+T cells occur in different splenic compartments during infection with Plasmodium berghei.

    Science.gov (United States)

    Bayarsaikhan, Ganchimeg; Miyakoda, Mana; Yamamoto, Kazuo; Kimura, Daisuke; Akbari, Masoud; Yuda, Masao; Yui, Katsuyuki

    2017-06-01

    The spleen is the major organ in which T cells are primed during infection with malaria parasites. However, little is known regarding the dynamics of the immune responses and their localization within the splenic tissue during malaria infection. We examined murine CD8 + T cell responses during infection with Plasmodium berghei using recombinant parasites expressing a model antigen ovalbumin (OVA) protein and compared the responses with those elicited by Listeria monocytogenes expressing the same antigen. OVA-specific CD8 + T cells were mainly activated in the white pulp of the spleen during malaria infection, as similarly observed during Listeria infection. However, the fates of these activated CD8 + T cells were distinct. During infection with malaria parasites, activated CD8 + T cells preferentially accumulated in the red pulp and/or marginal zone, where cytokine production of OVA-specific CD8 + T cells decreased, and the expression of multiple inhibitory receptors increased. These cells preferentially underwent apoptosis, suggesting that T cell exhaustion mainly occurred in the red pulp and/or marginal zone. However, during Listeria infection, OVA-specific CD8 + T cells only transiently expressed inhibitory receptors in the white pulp and maintained their ability to produce cytokines and become memory cells. These results highlighted the distinct fates of CD8 + T cells during infection with Plasmodium parasites and Listeria, and suggested that activation and exhaustion of specific CD8 + T cells occurred in distinct spleen compartments during infection with malaria parasites. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. CD8+mycosis fungoides: A low-grade lymphoproliferative disorder.

    Science.gov (United States)

    Martinez-Escala, Maria Estela; Kantor, Robert W; Cices, Ahuva; Zhou, Xiaolong A; Kaplan, Jason B; Pro, Barbara; Choi, Jaehyuk; Guitart, Joan

    2017-09-01

    The prognosis of the CD8 + subtype of mycosis fungoides (MF) is controversial. Although most authors believe that determining the presence of this cell surface antigen has no prognostic value, others have observed a more indolent course for CD8 + MF compared with CD4 + MF. To review the cases of CD8 + MF in the pediatric and adult populations seen at our institution. This is a retrospective review of clinical and pathologic data. Age, stage at presentation, and outcomes of patients at our institution were compared with those of 2 large MF cohorts that predominantly were CD4 + from the relevant literature. Sixty-seven patients of a median age of 46 years were included. A higher frequency of early-stage disease was observed for CD8 + MF patients at diagnosis when compared with other cohorts, including 31 (47%) patients with stage IA, 33 (50%) with stage IB, and 2 (3%) with stage IIB (P = .001, P = .001, and P = .002, respectively). With a median follow-up (5.5 years, range 0.2-21 years) similar to other cohorts, a higher rate of complete remission was achieved (65.5%, P = .001), and a lower rate of progression was observed (P = .004). This is a retrospective review. Our experience with CD8 + MF confirms a more indolent course of disease with this MF variant. Our results warrant a conservative treatment approach limited to skin-directed therapies and observation in most patients. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  14. Multiscale Modeling of the Early CD8 T-Cell Immune Response in Lymph Nodes: An Integrative Study

    Directory of Open Access Journals (Sweden)

    Sotiris A. Prokopiou

    2014-09-01

    Full Text Available CD8 T-cells are critical  in controlling infection by intracellular  pathogens. Upon encountering antigen presenting cells, T-cell receptor activation promotes the differentiation of naïve CD8 T-cells into strongly proliferating  activated and effector stages. We propose a 2D-multiscale computational model to study the maturation of CD8 T-cells in a lymph node controlled by their molecular profile. A novel molecular pathway is presented and converted into an ordinary differential  equation model, coupled with a cellular Potts model to describe cell-cell interactions. Key molecular  players such as activated IL2 receptor and Tbet levels  control the differentiation  from naïve into activated and effector stages, respectively,  while caspases and Fas-Fas ligand interactions control cell apoptosis.  Coupling  this molecular model to the cellular scale successfully  reproduces  qualitatively the evolution of total CD8 T-cell counts observed in mice lymph node, between Day 3 and 5.5 post-infection. Furthermore, this model allows us to make testable predictions  of the evolution of the different CD8 T-cell stages.

  15. Lack of common TCRA and TCRB clonotypes in CD8+/ TCRαβ+ T-cell large granular lymphocyte leukemia: A review on the role of antigenic selection in the immunopathogenesis of CD8+ T-LGL

    NARCIS (Netherlands)

    Y. Sandberg (Yorick); M.J. Kallemeijn (Martine); W.A. Dik (Willem); D. Tielemans; I.L.M. Wolvers-Tettero (I. L M); E.J. van Gastel-Mol (Ellen); T. Szczepanski (Tomasz); Y. Pol (Y.); N. Darzentas (Nikos); J.J.M. van Dongen (Jacques); A.W. Langerak (Anton)

    2014-01-01

    textabstractClonal CD8 +/T-cell receptor (TCR)αβ+ T-cell large granular lymphocyte (T-LGL) proliferations constitute the most common subtype of T-LGL leukemia. Although the etiology of T-LGL leukemia is largely unknown, it has been hypothesized that chronic antigenic stimulation contributes to the

  16. CD8+T cells expressing both PD-1 and TIGIT but not CD226 are dysfunctional in acute myeloid leukemia (AML) patients.

    Science.gov (United States)

    Wang, Mengjie; Bu, Jin; Zhou, Maohua; Sido, Jessica; Lin, Yu; Liu, Guanfang; Lin, Qiwen; Xu, Xiuzhang; Leavenworth, Jianmei W; Shen, Erxia

    2018-05-01

    Acute myeloid leukemia (AML) is one of the most common types of leukemia among adults with an overall poor prognosis and very limited treatment management. Immune checkpoint blockade of PD-1 alone or combined with other immune checkpoint blockade has gained impressive results in murine AML models by improving anti-leukemia CD8 + T cell function, which has greatly promoted the strategy to utilize combined immune checkpoint inhibitors to treat AML patients. However, the expression profiles of these immune checkpoint receptors, such as co-inhibitory receptors PD-1 and TIGIT and co-stimulatory receptor CD226, in T cells from AML patients have not been clearly defined. Here we have defined subsets of CD8 + and CD4 + T cells in the peripheral blood (PB) from newly diagnosed AML patients and healthy controls (HCs). We have observed increased frequencies of PD-1- and TIGIT- expressing CD8 + T cells but decreased occurrence of CD226-expressing CD8 + T cells in AML patients. Further analysis of these CD8 + T cells revealed a unique CD8 + T cell subset that expressed PD-1 and TIGIT but displayed lower levels of CD226 was associated with failure to achieve remission after induction chemotherapy and FLT3-ITD mutations which predict poor clinical prognosis in AML patients. Importantly, these PD-1 + TIGIT + CD226 - CD8 + T cells are dysfunctional with lower expression of intracellular IFN-γ and TNF-α than their counterparts in HCs. Therefore, our studies revealed that an increased frequency of a unique CD8 + T cell subset, PD-1 + TIGIT + CD226 - CD8 + T cells, is associated with CD8 + T cell dysfunction and poor clinical prognosis of AML patients, which may reveal critical diagnostic or prognostic biomarkers and direct more efficient therapeutic strategies. Copyright © 2017. Published by Elsevier Inc.

  17. Low expression of activation marker CD69 and chemokine receptors CCR5 and CXCR3 on memory T cells after 2009 H1N1 influenza A antigen stimulation in vitro following H1N1 vaccination of HIV-infected individuals.

    Science.gov (United States)

    Chawansuntati, Kriangkrai; Chotirosniramit, Nuntisa; Sugandhavesa, Patcharaphan; Aurpibul, Linda; Thetket, Sunida; Kosashunhanan, Natthapol; Supindham, Taweewat; Kaewthip, Oranitcha; Sroysuwan, Piyathida; Sirisanthana, Thira; Suparatpinyo, Khuanchai; Wipasa, Jiraprapa

    2015-01-01

    Unlike well-studied antibody responses to pandemic 2009 H1N1 influenza A virus vaccines in human immunodeficiency virus-infected (HIV+) individuals, less well understood are cell-mediated immune (CMI) responses to this antigen in this susceptible population. We investigated such influenza-specific CMI responses in 61 HIV+ individuals and in 20 HIV-negative (HIV-) healthy controls. Each was vaccinated with a single licensed dose of inactivated, split-virion vaccine comprised of the influenza A/California/7/2009 (H1N1) virus-like strain. Cells collected just prior to vaccination and at 1 and 3 months afterwards were stimulated in vitro with dialyzed vaccine antigen and assayed by flow cytometry for cytokines TNF-α, IFN-γ, IL-2, and IL-10, for degranulation marker CD107a, as well as phenotypes of memory T-cell subpopulations. Comparable increases of cytokine-producing and CD107a-expressing T cells were observed in both HIV+ subjects and healthy HIV-controls. However, by 3 months post-vaccination, in vitro antigen stimulation of peripheral blood mononuclear cells induced greater expansion in controls of both CD4 and CD8 central memory and effector memory T cells, as well as higher expression of the activation marker CD69 and chemokine receptors CCR5 and CXCR3 than in HIV+ subjects. We concluded CD4+ and CD8+ memory T cells produce cytokines at comparable levels in both groups, whereas the expression after in vitro stimulation of molecules critical for cell migration to infection sites are lower in the HIV+ than in comparable controls. Further immunization strategies against influenza are needed to improve the CMI responses in people living with HIV.

  18. Low CD4/CD8 T-Cell Ratio Associated with Inflammatory Arthropathy in Human T-Cell Leukemia Virus Type I Tax Transgenic Mice

    Science.gov (United States)

    Ohsugi, Takeo; Kumasaka, Toshio

    2011-01-01

    Background Human T-cell leukemia virus type I (HTLV-1) can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATL) as well as inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A transgenic mouse that expresses HTLV-1 Tax also develops T-cell leukemia/lymphoma and an inflammatory arthropathy that resembles rheumatoid arthritis. The aim of this study was to identify the primary T-cell subsets involved in the development of arthropathy in Tax transgenic mice. Principal Findings By 24 months of age, Tax transgenic mice developed severe arthropathy with a cumulative incidence of 22.8%. The pathological findings of arthropathy in Tax transgenic mice were similar to those seen in human rheumatoid arthritis or mouse models of rheumatoid arthritis, with synovial proliferation and a positive rheumatoid factor. Before the onset of spontaneous arthropathy, young and old Tax transgenic mice were not sensitive to collagen and did not develop arthritis after immunization with type II collagen. The arthropathic Tax transgenic mice showed a significantly decreased proportion of splenic CD4+ T cells, whereas the proportion of splenic CD8+ T cells was increased. Regulatory T cells (CD4+CD25+Foxp3+) were significantly decreased and CD8+ T cells that expressed the chemokine receptor CCR4 (CD8+CCR4+) were significantly increased in arthropathic Tax transgenic mice. The expression of tax mRNA was strong in the spleen and joints of arthropathic mice, with a 40-fold increase compared with healthy transgenic mice. Conclusions Our findings reveal that Tax transgenic mice develop rheumatoid-like arthritis with proliferating synovial cells in the joints; however, the proportion of different splenic T-cell subsets in these mice was completely different from other commonly used animal models of rheumatoid arthritis. The crucial T-cell subsets in arthropathic Tax transgenic mice appear to resemble those in HAM/TSP patients

  19. Low CD4/CD8 T-cell ratio associated with inflammatory arthropathy in human T-cell leukemia virus type I Tax transgenic mice.

    Directory of Open Access Journals (Sweden)

    Takeo Ohsugi

    Full Text Available BACKGROUND: Human T-cell leukemia virus type I (HTLV-1 can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATL as well as inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. A transgenic mouse that expresses HTLV-1 Tax also develops T-cell leukemia/lymphoma and an inflammatory arthropathy that resembles rheumatoid arthritis. The aim of this study was to identify the primary T-cell subsets involved in the development of arthropathy in Tax transgenic mice. PRINCIPAL FINDINGS: By 24 months of age, Tax transgenic mice developed severe arthropathy with a cumulative incidence of 22.8%. The pathological findings of arthropathy in Tax transgenic mice were similar to those seen in human rheumatoid arthritis or mouse models of rheumatoid arthritis, with synovial proliferation and a positive rheumatoid factor. Before the onset of spontaneous arthropathy, young and old Tax transgenic mice were not sensitive to collagen and did not develop arthritis after immunization with type II collagen. The arthropathic Tax transgenic mice showed a significantly decreased proportion of splenic CD4(+ T cells, whereas the proportion of splenic CD8(+ T cells was increased. Regulatory T cells (CD4(+CD25(+Foxp3(+ were significantly decreased and CD8(+ T cells that expressed the chemokine receptor CCR4 (CD8(+CCR4(+ were significantly increased in arthropathic Tax transgenic mice. The expression of tax mRNA was strong in the spleen and joints of arthropathic mice, with a 40-fold increase compared with healthy transgenic mice. CONCLUSIONS: Our findings reveal that Tax transgenic mice develop rheumatoid-like arthritis with proliferating synovial cells in the joints; however, the proportion of different splenic T-cell subsets in these mice was completely different from other commonly used animal models of rheumatoid arthritis. The crucial T-cell subsets in arthropathic Tax transgenic mice appear to resemble

  20. Acquired transcriptional programming in functional and exhausted virus-specific CD8 T cells.

    Science.gov (United States)

    Youngblood, Ben; Wherry, E John; Ahmed, Rafi

    2012-01-01

    Failure to control viral infections such as HIV results in T-cell receptor (TCR) and inhibitory receptor driven exhaustion of antigen-specific T cells. Persistent signaling by these receptors during chronic viral infection sculpts the transcriptional regulatory programs of virus-specific T cells. The resulting gene expression profile is tailored to temper the potentially damaging effector functions of cytotoxic T cells and adapt them to an antigen-rich and inflammation-rich environment. Here we review recent studies investigating mechanisms of transcriptional regulation of effector, functional memory, and exhausted T-cell functions during acute versus chronic infections. Patterns of gene expression in virus-specific CD8 T cells are a result of a combination of pro and inhibitory signals from antigen presentation (TCR-mediated) and co-inhibitory receptor ligation (PD-1, 2B4). Further, memory-specific transcriptional regulation of 2B4 expression and signaling impose a self-limiting secondary effector response to a prolonged viral infection. Additionally, differentiation of functional memory CD8 T cells is coupled with acquisition of a repressive epigenetic program for PD-1 expression. However, chronic infection provides a signal that blocks the acquisition of these epigenetic modifications reinforcing the suppression of cytotoxic lymphocyte (CTL) functions in exhausted cells. Current findings suggest that the mechanism(s) that delineate functional memory versus exhaustion are coupled with acquisition of transcriptional programs at the effector stage of differentiation, reinforced by cessation or persistence of TCR signaling.

  1. Translation is actively regulated during the differentiation of CD8+ effector T cells.

    Science.gov (United States)

    Araki, Koichi; Morita, Masahiro; Bederman, Annelise G; Konieczny, Bogumila T; Kissick, Haydn T; Sonenberg, Nahum; Ahmed, Rafi

    2017-09-01

    Translation is a critical process in protein synthesis, but translational regulation in antigen-specific T cells in vivo has not been well defined. Here we have characterized the translatome of virus-specific CD8 + effector T cells (T eff cells) during acute infection of mice with lymphocytic choriomeningitis virus (LCMV). Antigen-specific T cells exerted dynamic translational control of gene expression that correlated with cell proliferation and stimulation via the T cell antigen receptor (TCR). The translation of mRNAs that encode translation machinery, including ribosomal proteins, was upregulated during the T cell clonal-expansion phase, followed by inhibition of the translation of those transcripts when the CD8 + T eff cells stopped dividing just before the contraction phase. That translational suppression was more pronounced in terminal effector cells than in memory precursor cells and was regulated by antigenic stimulation and signals from the kinase mTOR. Our studies show that translation of transcripts encoding ribosomal proteins is regulated during the differentiation of CD8 + T eff cells and might have a role in fate 'decisions' involved in the formation of memory cells.

  2. The immunometabolite S-2-hydroxyglutarate regulates CD8+ T-lymphocyte fate

    Science.gov (United States)

    Tyrakis, Petros A.; Palazon, Asis; Macias, David; Lee, Kian. L.; Phan, Anthony. T.; Veliça, Pedro; You, Jia; Chia, Grace S.; Sim, Jingwei; Doedens, Andrew; Abelanet, Alice; Evans, Colin E.; Griffiths, John R.; Poellinger, Lorenz; Goldrath, Ananda. W.; Johnson, Randall S.

    2016-01-01

    R-2-hydroxyglutarate accumulates to millimolar levels in cancers with gain-of-function isocitrate dehydrogenase 1/2 mutations. These levels of R-2-hydroxyglutarate affect 2-oxoglutarate-dependent dioxygenases. Both R- and S-2-hydroxyglutarate, the other enantiomer of this metabolite, are detectible in healthy individuals, yet their physiological function remains elusive. Here we show that CD8+ T-lymphocytes accumulate 2-hydroxyglutarate in response to T-cell receptor triggering. This increases to millimolar levels in physiological oxygen conditions, via a hypoxia inducible factor 1 alpha-dependent mechanism. S-2-hydroxyglutarate predominates over R-2-hydroxyglutarate in activated T cells, and we demonstrate alterations in markers of CD8+ T-lymphocyte differentiation in response to this metabolite. Modulation of histone and DNA demethylation as well as hypoxia inducible factor 1 alpha stability mediate these effects. S-2-hydroxyglutarate treatment greatly enhances the in vivo proliferation, persistence and anti-tumour capacity of adoptively transferred CD8+ T-lymphocytes. Thus S-2-hydroxyglutarate acts as an immunometabolite that links environmental context, via a metabolic-epigenetic axis, to immune fate and function. PMID:27798602

  3. In vivo proliferation of naïve and memory influenza-specific CD8(+) T cells

    DEFF Research Database (Denmark)

    Flynn, K J; Riberdy, J M; Christensen, Jan Pravsgaard

    1999-01-01

    The virus-specific CD8(+) T cell response has been analyzed through the development, effector, and recovery phases of primary and secondary influenza pneumonia. Apparently, most, if not all, memory T cells expressing clonotypic receptors that bind a tetrameric complex of influenza nucleoprotein (NP......)(366-374) peptide+H-2D(b) (NPP) are induced to divide during the course of this localized respiratory infection. The replicative phase of the recall response ends about the time that virus can no longer be recovered from the lung, whereas some primary CD8(+)NPP(+) T cells may proliferate for a few more...

  4. HIV-infected women have high numbers of CD103-CD8+ T cells residing close to the basal membrane of the ectocervical epithelium.

    Science.gov (United States)

    Gibbs, Anna; Buggert, Marcus; Edfeldt, Gabriella; Ranefall, Petter; Introini, Andrea; Cheuk, Stanley; Martini, Elisa; Eidsmo, Liv; Ball, Terry B; Kimani, Joshua; Kaul, Rupert; Karlsson, Annika C; Wählby, Carolina; Broliden, Kristina; Tjernlund, Annelie

    2017-12-20

    Genital mucosa is the main portal of entry for various incoming pathogens, including HIV, hence an important site for host immune defenses. Tissue-resident memory T (TRM) cells defend tissue barriers against infections and are characterized by expression of CD103 and CD69. Here we describe the composition of CD8+ TRM cells in the ectocervix of healthy and HIV-infected women. Study samples were collected from healthy Swedish and Kenyan HIV-infected and uninfected women. Customized computerized image-based in situ analysis was developed to assess the ectocervical biopsies. Genital mucosa and blood samples were assessed by flow cytometry. While ectocervical epithelium of healthy women was populated with bona fide CD8+ TRM cells (CD103+CD69+), HIV-infected women displayed high frequency of CD103-CD8+ cells residing close to their epithelial basal membrane. Accumulation of CD103-CD8+ cells was associated with chemokine expression in the ectocervix and HIV viral load. CD103+CD8+ and CD103-CD8+ T cells expressed cytotoxic effector molecules in the ectocervical epithelium of healthy and HIV-infected women. Additionally, HIV-infected women had decreased frequencies of circulating CD103+CD8+ T cells. Our data provide insight into the distribution of CD8+ TRM cells in human genital mucosa, a critically important location for immune defense against pathogens, including HIV. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  5. Involvement of CD8+ T Cells in Multiple Sclerosis

    Science.gov (United States)

    Salou, Marion; Nicol, Bryan; Garcia, Alexandra; Laplaud, David-Axel

    2015-01-01

    Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by focal demyelination patches associated with inflammatory infiltrates containing T lymphocytes. For decades, CD4+ T cells have been recognized as playing a major role in the disease, especially in animal models, which has led to the development of several therapies. However, interest has recently developed in the involvement of CD8+ T cells in MS following the analysis of infiltrating T cells in human brain lesions. A broad range of evidence now suggests that the pathological role of this T cell subset in MS may have been underestimated. In this review, we summarize the literature implicating CD8+ T cells in the pathophysiology of MS. We present data from studies in the fields of genetics, anatomopathology and immunology, mainly in humans but also in animal models of MS. Altogether, this strongly suggests that CD8+ T cells may be major effectors in the disease process, and that the development of treatments specifically targeting this subset would be germane. PMID:26635816

  6. CD4dullCD8bright double-positive T-lymphocytes have a phenotype of granzyme Bpos CD8pos memory T-lymphocytes

    NARCIS (Netherlands)

    Rentenaar, R. J.; Wever, P. C.; van Diepen, F. N.; Schellekens, P. T.; Wertheim, P. M.; ten Berge, I. J.

    1999-01-01

    BACKGROUND: T-lymphocytes that co-express CD4 and CD8 antigens may be found in small percentages in the peripheral blood of healthy individuals, and have a CD4brightCD8dull phenotype. CD4dullCD8bright T-lymphocytes have been found only in temporal association with some viral infections. METHODS:

  7. Angiogenic peptide (AG)-30/5C activates human keratinocytes to produce cytokines/chemokines and to migrate and proliferate via MrgX receptors.

    Science.gov (United States)

    Kiatsurayanon, Chanisa; Niyonsaba, François; Chieosilapatham, Panjit; Okumura, Ko; Ikeda, Shigaku; Ogawa, Hideoki

    2016-09-01

    In addition to their antimicrobial activities, antimicrobial peptides, also known as host defense peptides (HDPs) activate keratinocytes; promote wound healing; and improve the skin barrier. AG-30/5C is a novel angiogenic HDP that activates various functions of fibroblasts and endothelial cells, including cytokine/chemokine production and wound healing. To investigate whether AG-30/5C activates human keratinocytes and to examine the underlying mechanisms. Production of cytokines/chemokines was assessed by ELISA. Expression of Mas-related G-protein coupled receptors X (MrgXs) in keratinocytes was determined by real-time PCR and Western blot. MAPK and NF-κB activation was analysed by Western blot. Cell migration was assessed by chemotaxis microchamber and in vitro wound closure assay, whereas cell proliferation was analysed using an XTT assay. We found that AG-30/5C was more efficient than its parent peptide AG-30 in increasing the production of various cytokines/chemokines and promoting keratinocyte migration and proliferation. Furthermore, MrgX3 and MrgX4 receptors were constitutively expressed in keratinocytes at higher levels than MrgX1 and MrgX2, and were up-regulated upon stimulation with TLR ligands. Because MrgX3 and MrgX4 siRNAs suppressed AG-30/5C-mediated cytokine/chemokine production, keratinocyte migration and proliferation, we propose that AG-30/5C utilizes these MrgXs to stimulate keratinocytes. In addition, AG-30/5C-induced activation of keratinocytes was controlled by MAPK and NF-κB pathways, as evidenced by the inhibitory effects of ERK-, JNK-, p38- and NF-κB-specific inhibitors. Indeed, we confirmed that AG-30/5C enhanced phosphorylation of MAPKs and IκB. Our findings provide novel evidence that AG-30/5C may be a useful therapeutic agent for wound healing by activating human keratinocytes. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  8. T-bet and Eomes Are Differentially Linked to the Exhausted Phenotype of CD8+T Cells in HIV Infection

    DEFF Research Database (Denmark)

    Buggert, Marcus; Tauriainen, Johanna; Yamamoto, Takuya

    2014-01-01

    . Here, we examined the relationship between these transcription factors and the expression of several inhibitory receptors (PD-1, CD160, and 2B4), functional characteristics and memory differentiation of CD8+ T cells in chronic and treated HIV infection. The expression of PD-1, CD160, and 2B4 on total...... displayed a balanced expression pattern of T-bet and Eomes. The T-betdimEomeshi virus-specific CD8+ T cells did not show features of terminal differentiation, but rather a transitional memory phenotype with poor polyfunctional (effector) characteristics. The transitional and exhausted phenotype of HIV...... to an inverse expression balance between T-bet and Eomes, which is not reversed despite long-term viral control through ART. These results aid to explain the inability of HIV-specific CD8+ T cells to control the viral replication post-ART cessation....

  9. The CXC chemokine receptor encoded by herpesvirus saimiri, ECRF3, shows ligand-regulated signaling through Gi, Gq, and G12/13 proteins but constitutive signaling only through Gi and G12/13 proteins

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; McLean, Katherine A; Holst, Peter J

    2004-01-01

    Open reading frame 74 (ORF74) of many gamma(2)-herpesviruses encodes a CXC chemokine receptor. The molecular pharmacological profile of ORF74 from herpesvirus saimiri, ECRF3, is characterized here and compared with that of the well known ORF74 from human herpesvirus 8 (HHV8). The ECRF3 receptor b...... ligand selectivity of ECRF3 among ORF74 receptors could reflect differences in the cellular tropism of the gamma(2)-herpesviruses....

  10. Efficacious early antiviral activity of HIV Gag- and Pol-specific HLA-B 2705-restricted CD8+ T cells

    DEFF Research Database (Denmark)

    Payne, Rebecca P; Kløverpris, Henrik; Sacha, Jonah B

    2010-01-01

    control of HIV, we first characterized the CD8(+) T-cell responses of nine highly active antiretroviral therapy (HAART)-naïve B 2705-positive subjects. Unexpectedly, we observed a strong response to an HLA-B 2705-restricted Pol epitope, KRKGGIGGY (KY9), in 8/9 subjects. The magnitude of the KY9 response...... by the respective CD8(+) T-cell response. By comparing inhibitions of viral replication by CD8(+) T cells specific for the Gag KK10, Pol KY9, and Vpr VL9 HLA-B 2705-restricted epitopes, we observed a consistent hierarchy of antiviral efficacy (Gag KK10 > Pol KY9 > Vpr VL9). This hierarchy was associated with early...... recognition of HIV-1-infected cells, within 6 h of infection, by KK10- and KY9-specific CD8(+) T cells but not until 18 h postinfection by VL9-specific CD8(+) T cells. There was no association between antiviral efficacy and proliferative capacity, cytotoxicity, polyfunctionality, or T-cell receptor (TCR...

  11. Monitoring of local CD8 β-expressing cell populations during Eimeria tenella infection of naïve and immune chickens

    DEFF Research Database (Denmark)

    Wattrang, Eva; Thebo, Per; Lunden, Anna

    2016-01-01

    The purpose of this study was to monitor abundance and activation of local CD8β-expressing T-cell populations during Eimeria tenella infections of naïve chickens and chickens immune by previous infections. Chickens were infected with E. tenella up to three times. Caecal T-cell receptor (TCR) γ/δ-CD......8β+ cells (cytotoxic T lymphocytes; CTL) and TCRγ/δ+CD8β+ cells were characterized with respect to activation markers (blast transformation, CD25 and cell surface CD107a). Cells were also induced to degranulate in vitro as a measure of activation potential. Major findings included a prominent long...

  12. Chronic Trypanosoma cruzi-elicited cardiomyopathy: from the discovery to the proposal of rational therapeutic interventions targeting cell adhesion molecules and chemokine receptors--how to make a dream come true.

    Science.gov (United States)

    Lannes-Vieira, Joseli; Silverio, Jaline Coutinho; Pereira, Isabela Resende; Vinagre, Nathália Ferreira; Carvalho, Cristiano Marcelo Espinola; Paiva, Cláudia Neto; Silva da, Andréa Alice

    2009-07-01

    One hundred years ago, Carlos Chagas discovered a new disease, the American trypanosomiasis. Chagas and co-workers later characterised the disease's common manifestation, chronic cardiomyopathy, and suggested that parasitic persistence coupled with inflammation was the key underlying pathogenic mechanism. Better comprehension of the molecular mechanisms leading to clinical heart afflictions is a prerequisite to developing new therapies that ameliorate inflammation and improve heart function without hampering parasite control. Here, we review recent data showing that distinct cell adhesion molecules, chemokines and chemokine receptors participate in anti-parasite immunity and/or detrimental leukocyte trafficking to the heart. Moreover, we offer evidence that CC-chemokine receptors may be attractive therapeutic targets aiming to regain homeostatic balance in parasite/host interaction thereby improving prognosis, supporting that it is becoming a non-phantasious proposal.

  13. Methods of Controlling Invasive Fungal Infections Using CD8+ T Cells

    Directory of Open Access Journals (Sweden)

    Pappanaicken R. Kumaresan

    2018-01-01

    Full Text Available Invasive fungal infections (IFIs cause high rates of morbidity and mortality in immunocompromised patients. Pattern-recognition receptors present on the surfaces of innate immune cells recognize fungal pathogens and activate the first line of defense against fungal infection. The second line of defense is the adaptive immune system which involves mainly CD4+ T cells, while CD8+ T cells also play a role. CD8+ T cell-based vaccines designed to prevent IFIs are currently being investigated in clinical trials, their use could play an especially important role in acquired immune deficiency syndrome patients. So far, none of the vaccines used to treat IFI have been approved by the FDA. Here, we review current and future antifungal immunotherapy strategies involving CD8+ T cells. We highlight recent advances in the use of T cells engineered using a Sleeping Beauty vector to treat IFIs. Recent clinical trials using chimeric antigen receptor (CAR T-cell therapy to treat patients with leukemia have shown very promising results. We hypothesized that CAR T cells could also be used to control IFI. Therefore, we designed a CAR that targets β-glucan, a sugar molecule found in most of the fungal cell walls, using the extracellular domain of Dectin-1, which binds to β-glucan. Mice treated with D-CAR+ T cells displayed reductions in hyphal growth of Aspergillus compared to the untreated group. Patients suffering from IFIs due to primary immunodeficiency, secondary immunodeficiency (e.g., HIV, or hematopoietic transplant patients may benefit from bioengineered CAR T cell therapy.

  14. CXC chemokine receptor 3 expression on CD34(+) hematopoietic progenitors from human cord blood induced by granulocyte-macrophage colony-stimulating factor

    DEFF Research Database (Denmark)

    Jinquan, T; Quan, S; Jacobi, H H

    2000-01-01

    -induced CD34(+) progenitor chemotaxis. These chemotactic attracted CD34(+) progenitors are colony-forming units-granulocyte-macrophage. gamma IP-10 and Mig also induced GM-CSF-stimulated CD34(+) progenitor adhesion and aggregation by means of CXCR3, a finding confirmed by the observation that anti-CXCR3 m......Ab blocked these functions of gammaIP-10 and Mig but not of chemokine stromal cell-derived factor 1 alpha. gamma IP-10-induced and Mig-induced up-regulation of integrins (CD49a and CD49b) was found to play a crucial role in adhesion of GM-CSF-stimulated CD34(+) progenitors. Moreover, gamma IP-10 and Mig...... stimulated CXCR3 redistribution and cellular polarization in GM-CSF-stimulated CD34(+) progenitors. These results indicate that CXCR3-gamma IP-10 and CXCR3-Mig receptor-ligand pairs, as well as the effects of GM-CSF on them, may be especially important in the cytokine/chemokine environment...

  15. Generalized Liver- and Blood-Derived CD8+ T-Cell Impairment in Response to Cytokines in Chronic Hepatitis C Virus Infection.

    Directory of Open Access Journals (Sweden)

    Stephanie C Burke Schinkel

    Full Text Available Generalized CD8+ T-cell impairment in chronic hepatitis C virus (HCV infection and the contribution of liver-infiltrating CD8+ T-cells to the immunopathogenesis of this infection remain poorly understood. It is hypothesized that this impairment is partially due to reduced CD8+ T-cell activity in response to cytokines such as IL-7, particularly within the liver. To investigate this, the phenotype and cytokine responsiveness of blood- and liver-derived CD8+ T-cells from healthy controls and individuals with HCV infection were compared. In blood, IL-7 receptor α (CD127 expression on bulk CD8+ T-cells in HCV infection was no different than controls yet was lower on central memory T-cells, and there were fewer naïve cells. IL-7-induced signalling through phosphorylated STAT5 was lower in HCV infection than in controls, and differed between CD8+ T-cell subsets. Production of Bcl-2 following IL-7 stimulation was also lower in HCV infection and inversely related to the degree of liver fibrosis. In liver-derived CD8+ T-cells, STAT5 activation could not be increased with cytokine stimulation and basal Bcl-2 levels of liver-derived CD8+ T-cells were lower than blood-derived counterparts in HCV infection. Therefore, generalized CD8+ T-cell impairment in HCV infection is characterized, in part, by impaired IL-7-mediated signalling and survival, independent of CD127 expression. This impairment is more pronounced in the liver and may be associated with an increased potential for apoptosis. This generalized CD8+ T-cell impairment represents an important immune dysfunction in chronic HCV infection that may alter patient health.

  16. Expression of co-stimulatory and adhesion molecules and chemokine or apoptosis receptors on acute myeloid leukaemia : high CD40 and CD11a expression correlates with poor prognosis

    NARCIS (Netherlands)

    Brouwer, RE; Hoefnagel, J; van der Burg, BB; Jedema, [No Value; Zwinderman, KH; Starrenburg, ICW; Kluin-Nelemans, HC; Barge, RMY; Willemze, R; Falkenburg, JHF

    2001-01-01

    The expression of adhesion and co-stimulatory molecules. and chemokine and death receptors such as tumour necrosis factor (TNF) and FAS on acute myeloid leukaemia (AML) may influence the biology of the disease and response to chemotherapy and immunotherapy. In this study, we analysed the expression

  17. Three phases of CD8 T cell response in the lung following H1N1 influenza infection and sphingosine 1 phosphate agonist therapy.

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    Melanie P Matheu

    Full Text Available Influenza-induced lung edema and inflammation are exacerbated by a positive feedback loop of cytokine and chemokine production termed a 'cytokine storm', a hallmark of increased influenza-related morbidity and mortality. Upon infection, an immune response is rapidly initiated in the lungs and draining lymph node, leading to expansion of virus-specific effector cells. Using two-photon microscopy, we imaged the dynamics of dendritic cells (DC and virus-specific eGFP(+CD8(+ T cells in the lungs and draining mediastinal lymph nodes during the first two weeks following influenza infection. Three distinct phases of T cell and CD11c(+ DC behavior were revealed: 1 Priming, facilitated by the arrival of lung DCs in the lymph node and characterized by antigen recognition and expansion of antigen-specific CD8(+ T cells; asymmetric T cell division in contact with DCs was frequently observed. 2 Clearance, during which DCs re-populate the lung and T cells leave the draining lymph node and re-enter the lung tissue where enlarged, motile T cells come into contact with DCs and form long-lived interactions. 3 Maintenance, characterized by T-cell scanning of the lung tissue and dissociation from local antigen presenting cells; the T cells spend less time in association with DCs and migrate rapidly on collagen. A single dose of a sphingosine-1-phosphate receptor agonist, AAL-R, sufficient to suppress influenza-induced cytokine-storm, altered T cell and DC behavior during influenza clearance, delaying T cell division, cellular infiltration in the lung, and suppressing T-DC interactions in the lung. Our results provide a detailed description of T cell and DC choreography and dynamics in the lymph node and the lung during influenza infection. In addition, we suggest that phase lags in T cell and DC dynamics induced by targeting S1P receptors in vivo may attenuate the intensity of the immune response and can be manipulated for therapeutic benefit.

  18. Pentoxifylline reverses chronic experimental Chagasic cardiomyopathy in association with repositioning of abnormal CD8+ T-cell response.

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    Isabela Resende Pereira

    2015-03-01

    Full Text Available Chronic chagasic cardiomyopathy (CCC, the main clinical sign of Chagas disease, is associated with systemic CD8+ T-cell abnormalities and CD8-enriched myocarditis occurring in an inflammatory milieu. Pentoxifylline (PTX, a phosphodiesterase inhibitor, has immunoregulatory and cardioprotective properties. Here, we tested PTX effects on CD8+ T-cell abnormalities and cardiac alterations using a model of experimental Chagas' heart disease.C57BL/6 mice chronically infected by the Colombian Trypanosoma cruzi strain and presenting signs of CCC were treated with PTX. The downmodulation of T-cell receptors on CD8+ cells induced by T. cruzi infection was rescued by PTX therapy. Also, PTX reduced the frequency of CD8+ T-cells expressing activation and migration markers in the spleen and the activation of blood vessel endothelial cells and the intensity of inflammation in the heart tissue. Although preserved interferon-gamma production systemically and in the cardiac tissue, PTX therapy reduced the number of perforin+ cells invading this tissue. PTX did not alter parasite load, but hampered the progression of heart injury, improving connexin 43 expression and decreasing fibronectin overdeposition. Further, PTX reversed electrical abnormalities as bradycardia and prolonged PR, QTc and QRS intervals in chronically infected mice. Moreover, PTX therapy improved heart remodeling since reduced left ventricular (LV hypertrophy and restored the decreased LV ejection fraction.PTX therapy ameliorates critical aspects of CCC and repositioned CD8+ T-cell response towards homeostasis, reinforcing that immunological abnormalities are crucially linked, as cause or effect, to CCC. Therefore, PTX emerges as a candidate to treat the non-beneficial immune deregulation associated with chronic Chagas' heart disease and to improve prognosis.

  19. Liver sinusoidal endothelial cells contribute to CD8 T cell tolerance toward circulating carcinoembryonic antigen in mice.

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    Höchst, Bastian; Schildberg, Frank A; Böttcher, Jan; Metzger, Christina; Huss, Sebastian; Türler, Andreas; Overhaus, Markus; Knoblich, Andreas; Schneider, Berthold; Pantelis, Dimitrios; Kurts, Christian; Kalff, Jörg C; Knolle, Percy; Diehl, Linda

    2012-11-01

    Immunity against cancer is impeded by local mechanisms promoting development of tumor-specific T cell tolerance, such as regulatory T cells, myeloid-derived suppressor cells, or immunosuppressive factors in the tumor microenvironment. The release of soluble antigens, such as carcinoembryonic antigen (CEA) from colorectal carcinoma (CRC) cells, has been investigated for diagnostic purposes, but not for its immunological consequences. Here, we address the question of whether soluble CEA influences tumor-specific immunity. Mice were injected with soluble CEA protein, and CEA-specific CD8 T cells were analyzed for their phenotype and functionality by means of restimulation ex vivo or antitumor efficacy in vivo. We furthermore characterized the CD8 T cell population in peripheral blood mononuclear cell (PBMCs) from healthy donors and colorectal carcinoma patients. In mice, circulating CEA was preferentially taken up in a mannose receptor-dependent manner and cross-presented by liver sinusoidal endothelial cells, but not dendritic cells, to CD8 T cells. Such systemically circulating CEA promoted tolerization of CEA-specific CD8 T cells in the endogenous T cell repertoire through the coinhibitory molecule B7H1. These CD8 T cells were not deleted but were rendered nonresponsive to antigen-specific stimulation and failed to control growth of CEA-expressing tumor cells. These nonresponsive CD8 T cells were phenotypically similar to central memory T cells being CD44(high) CD62L(high) CD25(neg) . We found T cells with a similar phenotype in PBMCs of healthy donors and at increased frequency also in patients with colorectal carcinoma. Our results provide evidence for the existence of an unrecognized tumor immune escape involving cross-presentation of systemically circulating tumor antigens that may influence immunotherapy of cancer. Copyright © 2012 American Association for the Study of Liver Diseases.

  20. The Microbiota Contributes to CD8+ T Cell Activation and Nutrient Malabsorption following Intestinal Infection with Giardia duodenalis.

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    Keselman, Aleksander; Li, Erqiu; Maloney, Jenny; Singer, Steven M

    2016-10-01

    Giardia duodenalis is a noninvasive luminal pathogen that impairs digestive function in its host in part by reducing intestinal disaccharidase activity. This enzyme deficiency has been shown in mice to require CD8(+) T cells. We recently showed that both host immune responses and parasite strain affected disaccharidase levels during murine giardiasis. However, high doses of antibiotics were used to facilitate infections in that study, and we therefore decided to systematically examine the effects of antibiotic use on pathogenesis and immune responses in the mouse model of giardiasis. We found that antibiotic treatment did not overtly increase the parasite burden but significantly limited the disaccharidase deficiency observed in infected mice. Moreover, while infected mice had more activated CD8(+) αβ T cells in the small intestinal lamina propria, this increase was absent in antibiotic-treated mice. Infection also led to increased numbers of CD4(+) αβ T cells in the lamina propria and activation of T cell receptor γδ-expressing intraepithelial lymphocytes (IEL), but these changes were not affected by antibiotics. Finally, we show that activated CD8(+) T cells express gamma interferon (IFN-γ) and granzymes but that granzymes are not required for sucrase deficiency. We conclude that CD8(+) T cells become activated in giardiasis through an antibiotic-sensitive process and contribute to reduced sucrase activity. These are the first data directly demonstrating activation of CD8(+) T cells and γδ T cells during Giardia infections. These data also demonstrate that disruption of the intestinal microbiota by antibiotic treatment prevents pathological CD8(+) T cell activation in giardiasis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  1. A temporal role of type I interferon signaling in CD8+ T cell maturation during acute West Nile virus infection.

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    Amelia K Pinto

    2011-12-01

    Full Text Available A genetic absence of the common IFN-α/β signaling receptor (IFNAR in mice is associated with enhanced viral replication and altered adaptive immune responses. However, analysis of IFNAR(-/- mice is limited for studying the functions of type I IFN at discrete stages of viral infection. To define the temporal functions of type I IFN signaling in the context of infection by West Nile virus (WNV, we treated mice with MAR1-5A3, a neutralizing, non cell-depleting anti-IFNAR antibody. Inhibition of type I IFN signaling at or before day 2 after infection was associated with markedly enhanced viral burden, whereas treatment at day 4 had substantially less effect on WNV dissemination. While antibody treatment prior to infection resulted in massive expansion of virus-specific CD8(+ T cells, blockade of type I IFN signaling starting at day 4 induced dysfunctional CD8(+ T cells with depressed cytokine responses and expression of phenotypic markers suggesting exhaustion. Thus, only the later maturation phase of anti-WNV CD8(+ T cell development requires type I IFN signaling. WNV infection experiments in BATF3(-/- mice, which lack CD8-α dendritic cells and have impaired priming due to inefficient antigen cross-presentation, revealed a similar effect of blocking IFN signaling on CD8(+ T cell maturation. Collectively, our results suggest that cell non-autonomous type I IFN signaling shapes maturation of antiviral CD8(+ T cell response at a stage distinct from the initial priming event.

  2. Pentoxifylline Reverses Chronic Experimental Chagasic Cardiomyopathy in Association with Repositioning of Abnormal CD8+ T-Cell Response

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    Pereira, Isabela Resende; Vilar-Pereira, Glaucia; Moreira, Otacilio Cruz; Ramos, Isalira Peroba; Gibaldi, Daniel; Britto, Constança; Moraes, Milton Ozório; Lannes-Vieira, Joseli

    2015-01-01

    Background Chronic chagasic cardiomyopathy (CCC), the main clinical sign of Chagas disease, is associated with systemic CD8+ T-cell abnormalities and CD8-enriched myocarditis occurring in an inflammatory milieu. Pentoxifylline (PTX), a phosphodiesterase inhibitor, has immunoregulatory and cardioprotective properties. Here, we tested PTX effects on CD8+ T-cell abnormalities and cardiac alterations using a model of experimental Chagas’ heart disease. Methodology/Principal Findings C57BL/6 mice chronically infected by the Colombian Trypanosoma cruzi strain and presenting signs of CCC were treated with PTX. The downmodulation of T-cell receptors on CD8+ cells induced by T. cruzi infection was rescued by PTX therapy. Also, PTX reduced the frequency of CD8+ T-cells expressing activation and migration markers in the spleen and the activation of blood vessel endothelial cells and the intensity of inflammation in the heart tissue. Although preserved interferon-gamma production systemically and in the cardiac tissue, PTX therapy reduced the number of perforin+ cells invading this tissue. PTX did not alter parasite load, but hampered the progression of heart injury, improving connexin 43 expression and decreasing fibronectin overdeposition. Further, PTX reversed electrical abnormalities as bradycardia and prolonged PR, QTc and QRS intervals in chronically infected mice. Moreover, PTX therapy improved heart remodeling since reduced left ventricular (LV) hypertrophy and restored the decreased LV ejection fraction. Conclusions/Significance PTX therapy ameliorates critical aspects of CCC and repositioned CD8+ T-cell response towards homeostasis, reinforcing that immunological abnormalities are crucially linked, as cause or effect, to CCC. Therefore, PTX emerges as a candidate to treat the non-beneficial immune deregulation associated with chronic Chagas' heart disease and to improve prognosis. PMID:25789471

  3. Early and Delayed Antiretroviral Therapy Results in Comparable Reductions in CD8+T Cell Exhaustion Marker Expression.

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    Rutishauser, Rachel Lena; Hartogensis, Wendy; Deguit, Christian Deo; Krone, Melissa; Hoh, Rebecca; Hecht, Frederick M; Pilcher, Christopher D; Bacchetti, Peter; Deeks, Steven G; Hunt, Peter W; McCune, Joseph M

    2017-07-01

    In untreated HIV infection, CD8 + T cell exhaustion (i.e., decreased proliferative and effector capacity) is associated with high levels of expression of coinhibitory receptors, including PD-1, T cell immunoreceptor with Ig and ITIM domains (TIGIT), CD160, and 2B4. This is evident for both HIV-specific and non-HIV-specific CD8 + T cells. Antiretroviral therapy (ART) initiated during chronic infection decreases but may not completely normalize the expression of such "exhaustion markers." Compared to initiation of ART later in the course of disease, initiation soon after infection reduces some parameters of chronic inflammation and adaptive immune dysfunction. However, it is not known if Early ART (e.g., initiated within the first 6 months after HIV infection) versus Delayed ART (e.g., initiated during chronic infection) preferentially reduces expression of exhaustion markers. We evaluated exhaustion marker expression on subsets of circulating effector and memory CD8 + T cells at longitudinal pre- and post-ART (2 and 5 years on ART) time points from n = 19 (Early ART) and n = 23 (Delayed ART) individuals. Before ART, TIGIT and CD160 were expressed on a statistically significantly higher proportion of effector and transitional memory cells from individuals in the Delayed ART group: the timing of ART initiation, however, did not consistently affect the expression of the exhaustion markers once viral suppression was achieved. Understanding which factors do and do not regulate aspects of CD8 + T cell exhaustion, including the expression of exhaustion markers, is critical to inform the rational design of CD8 + T cell-based therapies to treat HIV, for which CD8 + T cell exhaustion remains an important barrier to efficacy.

  4. Chemokine (C-C Motif) Receptor-Like 2 is not essential for lung injury, lung inflammation, or airway hyperresponsiveness induced by acute exposure to ozone.

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    Malik, Farhan; Cromar, Kevin R; Atkins, Constance L; Price, Roger E; Jackson, William T; Siddiqui, Saad R; Spencer, Chantal Y; Mitchell, Nicholas C; Haque, Ikram U; Johnston, Richard A

    2017-12-01

    Inhalation of ozone (O 3 ), a gaseous air pollutant, causes lung injury, lung inflammation, and airway hyperresponsiveness. Macrophages, mast cells, and neutrophils contribute to one or more of these sequelae induced by O 3 Furthermore, each of these aforementioned cells express chemokine (C-C motif) receptor-like 2 (Ccrl2), an atypical chemokine receptor that facilitates leukocyte chemotaxis. Given that Ccrl2 is expressed by cells essential to the development of O 3 -induced lung pathology and that chemerin, a Ccrl2 ligand, is increased in bronchoalveolar lavage fluid (BALF) by O 3 , we hypothesized that Ccrl2 contributes to the development of lung injury, lung inflammation, and airway hyperresponsiveness induced by O 3 To that end, we measured indices of lung injury (BALF protein, BALF epithelial cells, and bronchiolar epithelial injury), lung inflammation (BALF cytokines and BALF leukocytes), and airway responsiveness to acetyl- β -methylcholine chloride (respiratory system resistance) in wild-type and mice genetically deficient in Ccrl2 (Ccrl2-deficient mice) 4 and/or 24 hours following cessation of acute exposure to either filtered room air (air) or O 3 In air-exposed mice, BALF chemerin was greater in Ccrl2-deficient as compared to wild-type mice. O 3 increased BALF chemerin in mice of both genotypes, yet following O 3 exposure, BALF chemerin was greater in Ccrl2-deficient as compared to wild-type mice. O 3 increased indices of lung injury, lung inflammation, and airway responsiveness. Nevertheless, no indices were different between genotypes following O 3 exposure. In conclusion, we demonstrate that Ccrl2 modulates chemerin levels in the epithelial lining fluid of the lungs but does not contribute to the development of O 3 -induced lung pathology. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  5. Exacerbation of collagen induced arthritis by Fcγ receptor targeted collagen peptide due to enhanced inflammatory chemokine and cytokine production

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    Szarka E

    2012-04-01

    Full Text Available Eszter Szarka1*, Zsuzsa Neer1*, Péter Balogh2, Monika Ádori1, Adrienn Angyal1, József Prechl3, Endre Kiss1,3, Dorottya Kövesdi1, Gabriella Sármay11Department of Immunology, Eötvös Loránd University, 1117 Budapest, 2Department of Immunology and Biotechnology, University of Pécs, Pécs, 3Immunology Research Group of the Hungarian Academy of Science at Eötvös Loránd University, 1117 Budapest, Hungary*These authors contributed equally to this workAbstract: Antibodies specific for bovine type II collagen (CII and Fcγ receptors play a major role in collagen-induced arthritis (CIA, a mouse model of rheumatoid arthritis (RA. Our aim was to clarify the mechanism of immune complex-mediated inflammation and modulation of the disease. CII pre-immunized DBA/1 mice were intravenously boosted with extravidin coupled biotinylated monomeric CII-peptide epitope (ARGLTGRPGDA and its complexes with biotinylated FcγRII/III specific single chain Fv (scFv fragment. Disease scores were monitored, antibody titers and cytokines were determined by ELISA, and binding of complexes was detected by flow cytometry and immune histochemistry. Cytokine and chemokine secretion was monitored by protein profiler microarray. When intravenously administered into collagen-primed DBA/1 mice, both CII-peptide and its complex with 2.4G2 scFv significantly accelerated CIA and increased the severity of the disease, whereas the monomeric peptide and monomeric 2.4G2 scFv had no effect. FcγRII/III targeted CII-peptide complexes bound to marginal zone macrophages and dendritic cells, and significantly elevated the synthesis of peptide-specific IgG2a. Furthermore, CII-peptide containing complexes augmented the in vivo secretion of cytokines, including IL-10, IL-12, IL-17, IL-23, and chemokines (CXCL13, MIP-1, MIP-2. These data indicate that complexes formed by the CII-peptide epitope aggravate CIA by inducing the secretion of chemokines and the IL-12/23 family of pro

  6. HIV-1 Nef down-modulates C-C and C-X-C chemokine receptors via ubiquitin and ubiquitin-independent mechanism.

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    Prabha Chandrasekaran

    Full Text Available Human and Simian Immunodeficiency virus (HIV-1, HIV-2, and SIV encode an accessory protein, Nef, which is a pathogenesis and virulence factor. Nef is a multivalent adapter that dysregulates the trafficking of many immune cell receptors, including chemokine receptors (CKRs. Physiological endocytic itinerary of agonist occupied CXCR4 involves ubiquitinylation of the phosphorylated receptor at three critical lysine residues and dynamin-dependent trafficking through the ESCRT pathway into lysosomes for degradation. Likewise, Nef induced CXCR4 degradation was critically dependent on the three lysines in the C-terminal -SSLKILSKGK- motif. Nef directly recruits the HECT domain E3 ligases AIP4 or NEDD4 to CXCR4 in the resting state. This mechanism was confirmed by ternary interactions of Nef, CXCR4 and AIP4 or NEDD4; by reversal of Nef effect by expression of catalytically inactive AIP4-C830A mutant; and siRNA knockdown of AIP4, NEDD4 or some ESCRT-0 adapters. However, ubiquitinylation dependent lysosomal degradation was not the only mechanism by which Nef downregulated CKRs. Agonist and Nef mediated CXCR2 (and CXCR1 degradation was ubiquitinylation independent. Nef also profoundly downregulated the naturally truncated CXCR4 associated with WHIM syndrome and engineered variants of CXCR4 that resist CXCL12 induced internalization via an ubiquitinylation independent mechanism.

  7. Human CD8+ T cells from TB pleurisy respond to four immunodominant epitopes in Mtb CFP10 restricted by HLA-B alleles.

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    Li Li

    Full Text Available CD8(+ T cells are essential for host defense to Mycobacterium tuberculosis (Mtb infection and identification of CD8(+ T cell epitopes from Mtb is of importance for the development of effective peptide-based diagnostics and vaccines. We previously demonstrated that the secreted 10-KDa culture filtrate protein (CFP10 from Mtb is a potent CD8(+ T cell antigen but the repertoire and dominance pattern of human CD8 epitopes for CFP10 remained poorly characterized. In the present study, we undertook to define immunodominant CD8 epitopes involved in CFP10 using a panel of CFP10-derived 13-15 amino acid (aa peptides overlapping by 11 aa. Four peptides in CFP10 were observed to induce significant CD8(+ T cell responses and we further determined the size of the epitopes involved in each individual peptide tested. Four 9 aa CD8 epitopes were finally identified and deleting a single amino acid from the N or C terminus of either peptide markedly reduced IFN-γ production, suggesting that they are minimum of CD8 epitopes. In the individuals tested, each epitope represented a single immunodominant response in CD8(+ T cells. The epitope-specific CD8(+ T cells displayed effector or effector memory phenotypes and could upregulate the expression of CD107a/b upon antigen stimulation. In addition, we found that epitope-specific CD8(+ T cells shared biased usage of T cell receptor (TCR variable region of β chain (Vβ 12, 9, 7.2 or Vβ4 chains. As judged from HLA-typing results and using bioinformatics technology for prediction of MHC binding affinity, we found that the epitope-specific CD8(+ T cells are all restricted by HLA-B alleles. Our findings suggest that the four epitopes in CFP10 recognized by CD8(+ T cells might be of importance for the development of Mtb peptide-based vaccines and for improved diagnosis of TB in humans.

  8. Interferon-γ Prevents Death of Bystander Neurons during CD8 T Cell Responses in the Brain

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    Richter, Kirsten; Hausmann, Jürgen; Staeheli, Peter

    2009-01-01

    T cells restricted to neurotropic viruses are potentially harmful as their activity may result in the destruction of neurons. In the Borna disease virus (BDV) model, antiviral CD8 T cells entering the brain of infected mice cause neurological disease but no substantial loss of neurons unless the animals lack interferon-γ (IFN-γ). We show here that glutamate receptor antagonists failed to prevent BDV-induced neuronal loss in IFN-γ-deficient mice, suggesting that excitotoxicity resulting from glutamate receptor overstimulation is an unlikely explanation for the neuronal damage. Experiments with IFN-γ-deficient mice lacking eosinophils indicated that these cells, which specifically accumulate in the infected brains of IFN-γ-deficient mice, are not responsible for CA1 neuronal death. Interestingly, BDV-induced damage of CA1 neurons was reduced significantly in IFN-γ-deficient mice lacking perforin, suggesting a key role for CD8 T cells in this pathological process. Specific death of hippocampal CA1 neurons could be triggered by adoptive transfer of BDV-specific CD8 T cells from IFN-γ-deficient mice into uninfected mice that express transgene-encoded BDV antigen at high level in astrocytes. These results indicate that attack by CD8 T cells that cause the death of CA1 neurons might be directed toward regional astrocytes and that IFN-γ protects vulnerable CA1 neurons from collateral damage resulting from exposure to potentially toxic substances generated as a result of CD8 T cell-mediated impairment of astrocyte function. PMID:19359516

  9. Hyper-IL-15 suppresses metastatic and autochthonous liver cancer by promoting tumour-specific CD8+ T cell responses.

    Science.gov (United States)

    Cheng, Liang; Du, Xuexiang; Wang, Zheng; Ju, Jianqi; Jia, Mingming; Huang, Qibin; Xing, Qiao; Xu, Meng; Tan, Yi; Liu, Mingyue; Du, Peishuang; Su, Lishan; Wang, Shengdian

    2014-12-01

    Liver cancer has a very dismal prognosis due to lack of effective therapy. Here, we studied the therapeutic effects of hyper-interleukin15 (hyper-IL-15), which is composed of IL-15 and the sushi domain of the IL-15 receptor α chain, on metastatic and autochthonous liver cancers. Liver metastatic tumour models were established by intraportally injecting syngeneic mice with murine CT26 colon carcinoma cells or B16-OVA melanoma cells. Primary hepatocellular carcinoma (HCC) was induced by diethylnitrosamine (DEN). A hydrodynamics-based gene delivery method was used to achieve sustained hyper-IL-15 expression in the liver. Liver gene delivery of hyper-IL-15 robustly expanded CD8(+) T and NK cells, leading to a long-term (more than 40 days) accumulation of CD8(+) T cells in vivo, especially in the liver. Hyper-IL-15 treatment exerted remarkable therapeutic effects on well-established liver metastatic tumours and even on DEN-induced autochthonous HCC, and these effects were abolished by depletion of CD8(+) T cells but not NK cells. Hyper-IL-15 triggered IL-12 and interferon-γ production and reduced the expression of co-inhibitory molecules on dendritic cells in the liver. Adoptive transfer of T cell receptor (TCR) transgenic OT-1 cells showed that hyper-IL-15 preferentially expanded tumour-specific CD8(+) T cells and promoted their interferon-γ synthesis and cytotoxicity. Liver delivery of hyper-IL-15 provides an effective therapy against well-established metastatic and autochthonous liver cancers in mouse models by preferentially expanding tumour-specific CD8(+) T cells and promoting their anti-tumour effects. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  10. CD8+ Treg cells suppress CD8+ T cell-responses by IL-10-dependent mechanism during H5N1 influenza virus infection

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    Zou, Qiang; Wu, Bing; Xue, Jia; Fan, Xiaoxu; Feng, Congcong; Geng, Shuang; Wang, Ming; Wang, Bin

    2014-01-01

    Although Treg-cell-mediated suppression during infection or autoimmunity has been described, functions of Treg cells during highly pathogenic avian influenza virus infection remain poorly characterized. Here we found that in Foxp3-GFP transgenic mice, CD8+ Foxp3+ Treg cells, but not CD4+ Foxp3+ Treg cells, were remarkably induced during H5N1 infection. In addition to expressing CD25, the CD8+ Foxp3+ Treg cells showed a high level of GITR and produced IL-10. In an adoptive transfer model, CD8+ Treg cells suppressed CD8+ T-cell responses and promoted H5N1 virus infection, resulting in enhanced mortality and increased virus load in the lung. Furthermore, in vitro neutralization of IL-10 and studies with IL-10R-deficient mice in vitro and in vivo demonstrated an important role for IL-10 production in the capacity of CD8+ Treg cells to inhibit CD8+ T-cell responses. Our findings identify a previously unrecognized role of CD8+ Treg cells in the negative regulation of CD8+ T-cell responses and suggest that modulation of CD8+ Treg cells may be a therapeutic strategy to control H5N1 viral infection. PMID:24114149

  11. Transcriptional regulation during CD8 T-cell immune responses.

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    Munitic, Ivana; Evaristo, César; Sung, Hsueh Cheng; Rocha, Benedita

    2010-01-01

    Naïve CD8 T cells differentiate in response to antigen stimulation. They acquire the capacity to express multiple effector molecules and mediate effector functions that contribute to infection control. Once antigen loads are reduced they revert progressively to a less activated status and eventually reach a steady-state referred to as "memory" that is very different from that of naive cells. Indeed, these "memory" cells are "ready-to-go" populations that acquired the capacity to respond more efficiently to antigen stimulation. They modify their cell cycle machinery in order to divide faster; they likely improve DNA repair and other cell survival mechanisms in order to survive during division and thus to generate much larger clones of effector cells; finally, they also mediate effector functions much faster. These modifications are the consequence of changes in the expression of multiple genes, i.e., on the utilization of a new transcription program.

  12. Cigarette smoke increases TLR4 and TLR9 expression and induces cytokine production from CD8+ T cells in chronic obstructive pulmonary disease

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    Nadigel Jessica

    2011-11-01

    Full Text Available Abstract Background Cigarette smoke is a major risk factor for chronic obstructive pulmonary disease (COPD, an inflammatory lung disorder. COPD is characterized by an increase in CD8+ T cells within the central and peripheral airways. We hypothesized that the CD8+ T cells in COPD patients have increased Toll-like receptor (TLR expression compared to control subjects due to the exposure of cigarette smoke in the airways. Methods Endobronchial biopsies and peripheral blood were obtained from COPD patients and control subjects. TLR4 and TLR9 expression was assessed by immunostaining of lung tissue and flow cytometry of the peripheral blood. CD8+ T cells isolated from peripheral blood were treated with or without cigarette smoke condensate (CSC as well as TLR4 and TLR9 inhibitors. PCR and western blotting were used to determine TLR4 and TLR9 expression, while cytokine secretion from these cells was detected using electrochemiluminescence technology. Results No difference was observed in the overall expression of TLR4 and TLR9 in the lung tissue and peripheral blood of COPD patients compared to control subjects. However, COPD patients had increased TLR4 and TLR9 expression on lung CD8+ T cells. Exposure of CD8+ T cells to CSC resulted in an increase of TLR4 and TLR9 protein expression. CSC exposure also caused the activation of CD8+ T cells, resulting in the production of IL-1β, IL-6, IL-10, IL-12p70, TNFα and IFNγ. Furthermore, inhibition of TLR4 or TLR9 significantly attenuated the production of TNFα and IL-10. Conclusions Our results demonstrate increased expression of TLR4 and TLR9 on lung CD8+ T cells in COPD. CD8+ T cells exposed to CSC increased TLR4 and TLR9 levels and increased cytokine production. These results provide a new perspective on the role of CD8+ T cells in COPD.

  13. CD8+CD25+ T cells reduce atherosclerosis in apoE(−/−) mice

    International Nuclear Information System (INIS)

    Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning; Yano, Juliana; Lio, Wai Man; Trinidad, Portia; Honjo, Tomoyuki; Cercek, Bojan; Shah, Prediman K.; Chyu, Kuang-Yuh

    2014-01-01

    Highlights: •The role of a sub-population of CD8 + T cells with suppressor functions was investigated in atherosclerosis. •CD8 + CD25 + T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8 + CD25 + T cells reduced CD4 + T cell proliferation and CD8 + cytotoxic activity in vitro. •Adoptive transfer of CD8 + CD25 + T cells significantly reduced atherosclerosis. •CD8 + CD25 + T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8 + T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8 + CD25 + T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8 + CD25 + T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8 + CD25 + T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8 + CD25 + T cells from apoE(−/−) mice. Depletion of CD8 + CD25 + from total CD8 + T cells rendered higher cytolytic activity of the remaining CD8 + CD25 − T cells. Adoptive transfer of CD8 + CD25 + T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4 + T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8 + CD25 + T cells in experimental atherosclerosis

  14. Adenoviral Vector Vaccination Induces a Conserved Program of CD8+ T Cell Memory Differentiation in Mouse and Man

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    Beatrice Bolinger

    2015-11-01

    Full Text Available Following exposure to vaccines, antigen-specific CD8+ T cell responses develop as long-term memory pools. Vaccine strategies based on adenoviral vectors, e.g., those developed for HCV, are able to induce and sustain substantial CD8+ T cell populations. How such populations evolve following vaccination remains to be defined at a transcriptional level. We addressed the transcriptional regulation of divergent CD8+ T cell memory pools induced by an adenovector encoding a model antigen (beta-galactosidase. We observe transcriptional profiles that mimic those following infection with persistent pathogens, murine and human cytomegalovirus (CMV. Key transcriptional hallmarks include upregulation of homing receptors and anti-apoptotic pathways, driven by conserved networks of transcription factors, including T-bet. In humans, an adenovirus vaccine induced similar CMV-like phenotypes and transcription factor regulation. These data clarify the core features of CD8+ T cell memory following vaccination with adenovectors and indicate a conserved pathway for memory development shared with persistent herpesviruses.

  15. CD8-positive juvenile onset mycosis fungoides: an immunohistochemical and genotypic analysis of six cases.

    Science.gov (United States)

    Whittam, L R; Calonje, E; Orchard, G; Fraser-Andrews, E A; Woolford, A; Russell-Jones, R

    2000-12-01

    Childhood cases of cytotoxic T-cell lymphoma have not been well described. We have undertaken an immunohistochemical and genotypic analysis of patients presenting with juvenile onset mycosis fungoides (MF). Of 10 patients presenting over a 3-year period, six exhibited a CD8-positive phenotype. These six patients were also CD2, CD3 and TIA1 positive, but CD56 negative. Apart from the cytotoxic phenotype, these patients had clinicopathological features that were indistinguishable from ordinary cases of MF, with slowly evolving patches and plaques. Three patients were staged as 1A and three as 1B, with no evidence of nodal or systemic disease. Patients responded well to conventional therapy, with no evidence of disease progression after 3 years follow-up. Epidermotropism was a prominent feature in four of the six cytotoxic cases. In two patients with an equivocal histology the diagnosis was confirmed by the finding of a clonal population, using polymerase chain reaction/single strand conformational polymorphism analysis of the T-cell receptor gamma gene in lesional skin. The same technique revealed that all blood samples analysed were polyclonal. These data show that cytotoxic T-cell lymphoma can pursue an indolent course and that cases of CD8-positive MF may be over-represented in childhood.

  16. Clonal CD8+ T Cell Persistence and Variable Gene Usage Bias in a Human Transplanted Hand.

    Directory of Open Access Journals (Sweden)

    Joseph Y Kim

    Full Text Available Immune prophylaxis and treatment of transplanted tissue rejection act indiscriminately, risking serious infections and malignancies. Although animal data suggest that cellular immune responses causing rejection may be rather narrow and predictable based on genetic background, there are only limited data regarding the clonal breadth of anti-donor responses in humans after allogeneic organ transplantation. We evaluated the graft-infiltrating CD8+ T lymphocytes in skin punch biopsies of a transplanted hand over 178 days. Profiling of T cell receptor (TCR variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood. Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy. These 11 clones were limited to three TCR beta chain variable (BV gene families. Overall, these data indicate significant oligoclonality and likely restricted BV gene usage of alloreactive CD8+ T lymphocytes, and suggest that changes in rejection status are more due to varying regulation of their activity or number rather than shifts in the clonal populations in the transplanted organ. Given that controlled animal models produce predictable BV usage in T lymphocytes mediating rejection, understanding the determinants of TCR gene usage associated with rejection in humans may have application in specifically targeted immunotherapy.

  17. The possible role of virus-specific CD8(+) memory T cells in decidual tissue

    NARCIS (Netherlands)

    van Egmond, A.; van der Keur, C.; Swings, G. M. J. S.; Scherjon, S. A.; Claas, F. H. J.

    The most abundant lymphocyte present in decidual tissue is the CD8(+) T cell. It has been shown that most decidual CD8(+) T cells have an effector -memory phenotype, but expressed reduced levels of perforin and granzyme B compared with the peripheral CD8(+) effector -memory T cells. The specificity

  18. CD8+ T cells in human autoimmune arthritis : The unusual suspects

    NARCIS (Netherlands)

    Petrelli, Alessandra; Van Wijk, Femke

    2016-01-01

    CD8+ T cells are key players in the body's defence against viral infections and cancer. To date, data on the role of CD8+ T cells in autoimmune diseases have been scarce, especially when compared with the wealth of research on CD4+ T cells. However, growing evidence suggests that CD8+ T-cell

  19. B cells regulate thymic CD8+T cell differentiation in lupus-prone mice.

    Science.gov (United States)

    Xing, Chen; Zhu, Gaizhi; Xiao, He; Fang, Ying; Liu, Xiaoling; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Shen, Beifen; Li, Yan; Ma, Ning; Wang, Renxi

    2017-10-27

    Previous studies have shown that under normal physiological conditions thymic B cells play a critical function in T cell negative selection. We tested the effect of thymic B cells on thymic T-cell differentiation in autoimmune diseases including systemic lupus erythematosus (SLE). We found that thymic B cells and CD8 - CD4 + and CD4 - CD8 + T cells increased, whereas CD4 + CD8 + T cells decreased in lupus-prone mice. Once B cells were reduced, the change was reversed. Furthermore, we found that B cells blocked thymic immature single positive (ISP) CD4 - CD8 + CD3 lo/- RORγt - T cells progression into CD4 + CD8 + T cells. Interestingly, we found a novel population of thymic immature T cells (CD4 - CD8 + CD3 lo RORγt + ) that were induced into mature CD4 - CD8 + CD3 + RORγt + T cells by B cells in lupus-prone mice. Importantly, we found that IgG, produced by thymic B cells, played a critical role in the differentiation of thymic CD8 + ISP and mature RORγt + CD8 + T cells in lupus-prone mice. In conclusion, B cells blocked the differentiation from thymic CD8 + ISP and induced the differentiation of a novel immature CD4 - CD8 + CD3 lo RORγt + T cells into mature RORγt + CD8 + T cells by secreting IgG antibody in lupus-prone mice.

  20. The individuality of (virus-specific) CD8⁺ T cells

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    van Aalderen, M.C.

    2016-01-01

    CD8⁺ T cells are specialized in detecting intracellular pathology. As such, acute phase and memory CD8⁺ T cell responses form an essential line of defense against viral infections. Much of the current knowledge on virus-specific CD8⁺ T cell responses derives from mouse models. However, since mice do

  1. Immunization with radiation-attenuated Plasmodium berghei sporozoites induces liver cCD8alpha+DC that activate CD8+T cells against liver-stage malaria.

    Directory of Open Access Journals (Sweden)

    Ousman Jobe

    Full Text Available Immunization with radiation (gamma-attenuated Plasmodia sporozoites (gamma-spz confers sterile and long-lasting immunity against malaria liver-stage infection. In the P. berghei gamma-spz model, protection is linked to liver CD8+ T cells that express an effector/memory (T(EM phenotype, (CD44(hiCD45RB(loCD62L(lo, and produce IFN-gamma. However, neither the antigen presenting cells (APC that activate these CD8+ T(EM cells nor the site of their induction have been fully investigated. Because conventional (cCD8alpha+ DC (a subset of CD11c+ DC are considered the major inducers of CD8+ T cells, in this study we focused primarily on cCD8alpha+ DC from livers of mice immunized with Pb gamma-spz and asked whether the cCD8alpha+ DC might be involved in the activation of CD8+ T(EM cells. We demonstrate that multiple exposures of mice to Pb gamma-spz lead to a progressive and nearly concurrent accumulation in the liver but not the spleen of both the CD11c+NK1.1(- DC and CD8+ T(EM cells. Upon adoptive transfer, liver CD11c+NK1.1(- DC from Pb gamma-spz-immunized mice induced protective immunity against sporozoite challenge. Moreover, in an in vitro system, liver cCD8alpha(+ DC induced naïve CD8+ T cells to express the CD8+ T(EM phenotype and to secrete IFN-gamma. The in vitro induction of functional CD8+ T(EM cells by cCD8alpha+ DC was inhibited by anti-MHC class I and anti-IL-12 mAbs. These data suggest that liver cCD8alpha+ DC present liver-stage antigens to activate CD8+ T(EM cells, the pre-eminent effectors against pre-erythrocytic malaria. These results provide important implications towards a design of anti-malaria vaccines.

  2. Effects of chemokine receptor signalling on cognition-like, emotion-like and sociability behaviours of CCR6 and CCR7 knockout mice.

    Science.gov (United States)

    Jaehne, E J; Baune, B T

    2014-03-15

    Inflammation is regarded as an important mechanism of neuropsychiatric disorders. Chemokines, which are a part of the immune system, have effects on various aspects of brain function, but little is known about their effects on behaviour. We have compared the cognition-like behaviour (learning and spatial memory) of CCR6(-/-) and CCR7(-/-) mice with wild type (WT) C57BL/6 mice, in the Barnes maze, as well as a range of other behaviours, including exploratory, anxiety and depression-like behaviour, using a battery of tests. Levels of cytokines TNF-α, IL-1β and IL-6 were also measured. In the Barnes maze, CCR7(-/-) mice were shown to take longer to learn the location of the escape box on the 1st of 4 days of training. In the behavioural battery, CCR6(-/-) mice showed higher locomotor activity and lower anxiety in the open field test, and a lack of preference for social novelty in a sociability test. CCR7(-/-) mice behaved much like WT mice, although showed higher anxiety in Elevated Zero Maze. While baseline saccharin preference in a 2-bottle choice test, a test for anhedonia depression-like behaviour, was equal in all strains at baseline, weekly tests showed that both CCR6(-/-) and CCR7(-/-) mice developed a decreased preference for saccharin compared to WT over time. There were no differences between strains in any of the cytokines measured. These results suggest that chemokine receptors may play a role in cognition and learning behaviour, as well as anxiety and other behaviours, although the biological mechanisms are still unclear. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

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    Wang, Lei; Kuang, Lisha; Hitron, John Andrew; Son, Young-Ok; Wang, Xin; Budhraja, Amit [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Lee, Jeong-Chae [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Institute of Oral Biosciences and BK21 Program, Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Pratheeshkumar, Poyil [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Chen, Gang [Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Zhang, Zhuo [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Luo, Jia [Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

    2013-10-01

    Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′,5,7-trihydroxyflavone), a natural dietary flavonoid, suppressed CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other types of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. - Highlights: • Apigenin has a potential in preventing environmental arsenic induced carcinogenesis. • Apigenin suppresses CXCR4 in malignant transformed cells in vitro and in vivo. • The down-regulation of CXCR4 is mainly due to inhibition of NF-κB activity.

  4. Chemokine Receptor Expression Identifies Pre–T Helper (Th)1, Pre–Th2, and Nonpolarized Cells among Human CD4+ Central Memory T Cells

    Science.gov (United States)

    Rivino, Laura; Messi, Mara; Jarrossay, David; Lanzavecchia, Antonio; Sallusto, Federica; Geginat, Jens

    2004-01-01

    We previously reported that central–memory T cells (TCM cells), which express lymph node homing receptors CCR7 and CD62L, are largely devoid of effector functions but acquire characteristics of effector–memory T cells (TEM cells) (i.e., CCR7− T helper [Th]1 or Th2 cells) after stimulation with T cell receptor agonists or homeostatic cytokines. Here we show that three chemokine receptors identify functional subsets within the human CD4+ TCM cell pool. TCM cells expressing CXCR3 secreted low amounts of interferon γ, whereas CCR4+ TCM cells produced some interleukin (IL)-4, but not IL-5. In response to IL-7 and IL-15, CXCR3+ TCM and CCR4+ TCM cells invariably generated fully differentiated CCR7− Th1 and Th2 cells, respectively, suggesting that they represent pre-Th1 and pre-Th2 cells. Conversely, CXCR5+ TCM cells lacking CXCR3 and CCR4 remained nonpolarized and retained CCR7 and CD62L expression upon cytokine-driven expansion. Unlike naive cells, all memory subsets had a low T cell receptor rearrangement excision circle content, spontaneously incorporated bromodeoxyuridine ex vivo, and contained cells specific for tetanus toxoid. Conversely, recall responses to cytomegalovirus and vaccinia virus were largely restricted to CXCR3+ TCM and TEM cells. We conclude that antigen-specific memory T cells are distributed between TEM cells and different subsets of TCM cells. Our results also explain how the quality of primary T cell responses could be maintained by TCM cells in the absence of antigen. PMID:15381728

  5. The role of cytomegalovirus-encoded homologs of G protein-coupled receptors and chemokines in manipulation of and evasion from the immune system.

    Science.gov (United States)

    Vink, C; Smit, M J; Leurs, R; Bruggeman, C A

    2001-12-01

    Cytomegaloviruses (CMVs) have the ability to persist lifelong within the infected host. This ability implies that these viruses are highly adapted to their hosts. Most importantly, they will have to employ strategies to remain hidden from the host's immune system. Virus genes predicted to be involved in these strategies include genes encoding homologs of cellular immune effector or regulatory proteins, such as chemokine (CK) receptor-like G protein-coupled receptors (GPCRs), CKs and MHC class I molecules. These genes may have been