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Teunis B. H. Geijtenbeek - One of the best experts on this subject based on the ideXlab platform.

  • DC-SIGN in Infection and Immunity
    C-Type Lectin Receptors in Immunity, 2016
    Co-Authors: Joris K. Sprokholt, Ronald J. Overmars, Teunis B. H. Geijtenbeek
    Abstract:

    Dendritic cells (DCs) play a central role in the immune system by patrolling peripheral tissues to sample antigens to induce antigen-specific adaptive immune responses in lymphoid tissues. DCs express pattern recognition receptors such as toll-like receptors (TLRs), RIG-I-like receptors (RLRs), and C-type lectin receptors (CLRs) to interact with pathogens for antigen presentation and immune activation. One of the CLRs involved in different processes of DC function is DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN). DC-SIGN recognition of pathogens leads to efficient internalization and processing of antigen for MHC class I and II presentation. In addition, triggering of DC-SIGN induces intracellular signaling that affects immune responses. Although DC-SIGN signaling by itself does not lead to activation of transcription factors such as NFκB, it greatly modifies signaling pathways induced by other receptors, including TLRs, RLRs, and interferon receptors. Modulation of signaling pathways by DC-SIGN tailors adaptive immune responses to different pathogens by driving specific T-helper cell responses. Intriguingly, DC-SIGN signaling depends on the carbohydrate structures present on pathogens as mannose structures induce very different signaling cascades than fucose structures, providing DCs with the plasticity to tailor immune responses to a diverse range of pathogens. Several pathogens however have evolved to subvert DC-SIGN functions for effective infection of DCs and efficient transmission to target cells. In this chapter we will discuss DC-SIGN structure, expression, and DC-SIGN functionality in shaping adaptive immune responses and immunopathogenesis.

  • Glycodendrimers prevent HIV transmission via DC-SIGN on dendritic cells.
    International immunology, 2013
    Co-Authors: Juan J. Garcia-vallejo, Teunis B. H. Geijtenbeek, Hakan Kalay, Nathalie Koning, Martino Ambrosini, Ilona M. Vuist, Ramin Sarrami-forooshani, Yvette Van Kooyk
    Abstract:

    Dendritic cells (DCs) are antigen-presenting cells efficient in capturing pathogens, and processing their antigenic determinants for presentation to antigen-specific T cells to induce robust immune responses. Their location at peripheral tissues and the expression of pattern-recognition receptors, among them DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), facilitates the capture of pathogens before spreading. However, some pathogens have developed strategies to escape the immune system. One of the most successful is HIV-1, which targets DC-SIGN for transport to the lymph node where the virus infects CD4 + T cells. Contact of HIV-1 with DC-SIGN is thus the first event in the pathogenic cascade and, therefore, it is the primary target point for therapies aimed at HIV infection prevention. DC-SIGN recognizes specific glycans on HIV-1 and this interaction can be blocked by competitive inhibition through glycans. Although the affinity of glycans is relatively low, multivalency may increase avidity and the strength to compete with HIV-1 virions. We have designed multivalent dendrimeric compounds based on Lewis-type antigens that bind DC-SIGN with high selectivity and avidity and that effectively block gp120 binding to DC-SIGN and, consequently, HIV transmission to CD4 + T cells. Binding to DC-SIGN and gp120 inhibition was higher on glycodendrimers with larger molecular diameter, indicating that the geometry of the compounds is an important factor determining their functionality. Our compounds elicited DC-SIGN internalization, a property of the receptor upon triggering, but did not affect the maturation status of DCs. Thus, Le X glycodendrimers

  • Branched oligosaccharide structures on HBV prevent interaction with both DC-SIGN and L-SIGN
    Journal of Viral Hepatitis, 2008
    Co-Authors: M. L. Op Den Brouw, Teunis B. H. Geijtenbeek, M. A. W. P. De Jong, Irene S. Ludwig, Rg Van Der Molen, H.l.a. Janssen, Andrea M. Woltman
    Abstract:

    Hepatitis B virus (HBV) is a DNA virus that infects the liver as primary target. Currently, a high affinity receptor for HBV is still unknown. The dendritic cell specific C-type lectin DC-SIGN is involved in pathogen recognition through mannose and fucose containing carbohydrates leading to the induction of an anti-viral immune response. Many glycosylated viruses subvert this immune surveillance function and exploit DC-SIGN as a port of entry and for trans-infection of target cells. The glycosylation pattern on HBV surface antigens (HBsAg) together with the tissue distribution of HBV would allow interaction between HBV and DC-SIGN and its liver-expressed homologue L-SIGN. Therefore, a detailed study to investigate the binding of HBV to DC-SIGN and L-SIGN was performed. For HCV, both DC-SIGN and L-SIGN are known to bind envelope glycoproteins E1 and E2. Soluble DC-SIGN and L-SIGN specifically bound HCV virus-like particles, but no interaction with either HBsAg or HepG2.2.15-derived HBV was detected. Also, neither DC-SIGN nor L-SIGN transfected Raji cells bound HBsAg. In contrast, highly mannosylated HBV, obtained by treating HBV producing HepG2.2.15 cells with the alpha-mannosidase I inhibitor kifunensine, is recognized by DC-SIGN. The alpha-mannosidase I trimming of N-linked oligosaccharide structures thus prevents recognition by DC-SIGN. On the basis of these findings, it is tempting to speculate that HBV exploits mannose trimming as a way to escape recognition by DC-SIGN and thereby subvert a possible immune activation response

  • Measles Virus Targets DC-SIGN To Enhance Dendritic Cell Infection
    Journal of virology, 2006
    Co-Authors: Lot De Witte, Yvette Van Kooyk, Marion Abt, Sibylle Schneider-schaulies, Teunis B. H. Geijtenbeek
    Abstract:

    Dendritic cells (DCs) are involved in the pathogenesis of measles virus (MV) infection by inducing immune suppression and possibly spreading the virus from the respiratory tract to lymphatic tissues. It is becoming evident that DC function can be modulated by the involvement of different receptors in pathogen interaction. Therefore, we have investigated the relative contributions of different MV-specific receptors on DCs to MV uptake into and infection of these cells. DCs express the MV receptors CD46 and CD150, and we demonstrate that the C-type lectin DC-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) is a novel receptor for laboratory-adapted and wild-type MV strains. The ligands for DC-SIGN are both MV glycoproteins F and H. In contrast to CD46 and CD150, DC-SIGN does not support MV entry, since DC-SIGN does not confer susceptibility when stably expressed in CHO cells. However, DC-SIGN is important for the infection of immature DCs with MV, since both attachment and infection of immature DCs with MV are blocked in the presence of DC-SIGN inhibitors. Our data demonstrate that DC-SIGN is crucial as an attachment receptor to enhance CD46/CD150-mediated infection of DCs in cis. Moreover, MV might not only target DC-SIGN to infect DCs but may also use DC-SIGN for viral transmission and immune suppression.

  • interactions of dc sign with mac 1 and ceacam1 regulate contact between dendritic cells and neutrophils
    FEBS Letters, 2005
    Co-Authors: Klaas P J M Van Gisbergen, Irene S. Ludwig, Teunis B. H. Geijtenbeek, Yvette Van Kooyk
    Abstract:

    Early during infection neutrophils are the most important immune cells that are involved in killing of pathogenic bacteria and regulation of innate immune responses at the site of infection. It has become clear that neutrophils also modulate adaptive immunity through interactions with dendritic cells (DCs) that are pivotal in the induction of T cell responses. Upon activation, neutrophils release TNF-α and induce maturation of DCs that enables these antigen-presenting cells to stimulate T cell proliferation and to induce T helper 1 polarization. DC maturation by neutrophils also requires cellular interactions that are mediated by binding of the DC-specific receptor DC-SIGN to Mac-1 on the neutrophil. Here, we demonstrate that also CEACAM1 is an important ligand for DC-SIGN on neutrophils. Binding of DC-SIGN to both CEACAM1 and Mac-1 is required to establish cellular interactions with neutrophils. DC-SIGN is a C-type lectin that has specificity for Lewisx, and we show that DC-SIGN mediates binding to CEACAM1 through Lewisx moieties that are specifically expressed on CEACAM1 derived from neutrophils. This indicates that glycosylation-driven binding of both Mac-1 and CEACAM1 to DC-SIGN is essential for interactions of neutrophils with DCs and enables neutrophils to modulate T cell responses through interactions with DCs.

Yvette Van Kooyk - One of the best experts on this subject based on the ideXlab platform.

  • The physiological role of DC-SIGN: A tale of mice and men
    Trends in immunology, 2013
    Co-Authors: Juan J. Garcia-vallejo, Yvette Van Kooyk
    Abstract:

    The innate immune receptor DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin) was discovered over a decade ago and was initially identified as a pattern recognition receptor. In addition to its ability to recognize a broad range of pathogen-derived ligands and self-glycoproteins, DC-SIGN also mediates intercellular adhesion, as well as antigen uptake and signaling, which is a functional hallmark of dendritic cells (DCs). Most research on DC-SIGN has relied on in vitro studies. The in vivo function of DC-SIGN is difficult to address, in part because there are eight genetic homologs in mice with no clear DC-SIGN ortholog. Here, we summarize the functions attributed to DC-SIGN based on in vitro data and discuss the limitations of available mouse models to uncover the physiological role of this receptor in vivo.

  • Glycodendrimers prevent HIV transmission via DC-SIGN on dendritic cells.
    International immunology, 2013
    Co-Authors: Juan J. Garcia-vallejo, Teunis B. H. Geijtenbeek, Hakan Kalay, Nathalie Koning, Martino Ambrosini, Ilona M. Vuist, Ramin Sarrami-forooshani, Yvette Van Kooyk
    Abstract:

    Dendritic cells (DCs) are antigen-presenting cells efficient in capturing pathogens, and processing their antigenic determinants for presentation to antigen-specific T cells to induce robust immune responses. Their location at peripheral tissues and the expression of pattern-recognition receptors, among them DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), facilitates the capture of pathogens before spreading. However, some pathogens have developed strategies to escape the immune system. One of the most successful is HIV-1, which targets DC-SIGN for transport to the lymph node where the virus infects CD4 + T cells. Contact of HIV-1 with DC-SIGN is thus the first event in the pathogenic cascade and, therefore, it is the primary target point for therapies aimed at HIV infection prevention. DC-SIGN recognizes specific glycans on HIV-1 and this interaction can be blocked by competitive inhibition through glycans. Although the affinity of glycans is relatively low, multivalency may increase avidity and the strength to compete with HIV-1 virions. We have designed multivalent dendrimeric compounds based on Lewis-type antigens that bind DC-SIGN with high selectivity and avidity and that effectively block gp120 binding to DC-SIGN and, consequently, HIV transmission to CD4 + T cells. Binding to DC-SIGN and gp120 inhibition was higher on glycodendrimers with larger molecular diameter, indicating that the geometry of the compounds is an important factor determining their functionality. Our compounds elicited DC-SIGN internalization, a property of the receptor upon triggering, but did not affect the maturation status of DCs. Thus, Le X glycodendrimers

  • targeting glycan modified ova to murine dc sign transgenic dendritic cells enhances mhc class i and ii presentation
    Molecular Immunology, 2009
    Co-Authors: Satwinder Kaur Singh, Martin Schaefer, Johannes Stephani, Tim Sparwasser, Hakan Kalay, Juan J Garciavallejo, Joke Den M M Haan, Eirikur Saeland, Yvette Van Kooyk
    Abstract:

    Dendritic cells have gained much interest in the field of anti-cancer vaccine development because of their central function in immune regulation. One of the receptors that facilitate DC-specific targeting of antigens is the DC-specific C-type lectin DC-SIGN. Although DC-SIGN is specifically expressed on human DCs, its murine homologue is not present on any murine DC subsets, which makes in vivo evaluation of potential DC-SIGN targeting vaccines very difficult. Here we describe the use of DC-SIGN transgenic mice, as a good model system to evaluate DC-SIGN targeting vaccines. We demonstrate that glycan modification of OVA with DC-SIGN targeting glycans, targets antigen specifically to bone marrow (BM)** derived DCs and splenic DCs. Glycan modification of OVA with Lewis X or Lewis B oligosaccharides, that target DC-SIGN transgenic DCs, resulted in efficient 10-fold induction of OT-II compared to unmodified OVA. Interestingly, glycan modified OVA proteins were significantly cross-presented to OT-I T cells by wild type DC, 10-fold more than native OVA, and the expression of DC-SIGN further enhanced this cross-presentation. Targeting of glycosylated OVA was neither accompanied with any DC maturation, nor the production of inflammatory or anti-inflammatory cytokines. Thus, we conclude that glycan modification of antigens and targeting to DC-SIGN enhance both CD4 and CD8 T cell responses. Furthermore, our data demonstrate that DC-SIGN transgenic mice are valuable tool for optimisation and efficiency testing of DC vaccination strategies that are designed to target in particular the human DC-SIGN receptor.

  • Measles Virus Targets DC-SIGN To Enhance Dendritic Cell Infection
    Journal of virology, 2006
    Co-Authors: Lot De Witte, Yvette Van Kooyk, Marion Abt, Sibylle Schneider-schaulies, Teunis B. H. Geijtenbeek
    Abstract:

    Dendritic cells (DCs) are involved in the pathogenesis of measles virus (MV) infection by inducing immune suppression and possibly spreading the virus from the respiratory tract to lymphatic tissues. It is becoming evident that DC function can be modulated by the involvement of different receptors in pathogen interaction. Therefore, we have investigated the relative contributions of different MV-specific receptors on DCs to MV uptake into and infection of these cells. DCs express the MV receptors CD46 and CD150, and we demonstrate that the C-type lectin DC-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) is a novel receptor for laboratory-adapted and wild-type MV strains. The ligands for DC-SIGN are both MV glycoproteins F and H. In contrast to CD46 and CD150, DC-SIGN does not support MV entry, since DC-SIGN does not confer susceptibility when stably expressed in CHO cells. However, DC-SIGN is important for the infection of immature DCs with MV, since both attachment and infection of immature DCs with MV are blocked in the presence of DC-SIGN inhibitors. Our data demonstrate that DC-SIGN is crucial as an attachment receptor to enhance CD46/CD150-mediated infection of DCs in cis. Moreover, MV might not only target DC-SIGN to infect DCs but may also use DC-SIGN for viral transmission and immune suppression.

  • Carbohydrate specificities of the murine DC-SIGN homologue mSIGNR1.
    Immunobiology, 2005
    Co-Authors: Estella A Koppel, Yvette Van Kooyk, Irene S. Ludwig, Ben J. Appelmelk, Teunis B. H. Geijtenbeek
    Abstract:

    C-type lectins are important receptors expressed by antigen presenting cells that are involved in cellular communications as well as in pathogen uptake. An important C-type lectin family is represented by DC-SIGN and its homologues in human and mouse. Here we have investigated the carbohydrate specificity of cellular mSIGNR1 and compared it with DC-SIGN and L-SIGN. mSIGNR1 has a similar specificity as human DC-SIGN for high mannose-containing ligands present on both cellular and pathogen ligands. However, the DC-SIGN molecules differ in their recognition of Lewis antigens; mSIGNR1 interacts not only with Le(x/y) and Le(a/b) antigens similar to DC-SIGN, but also with sialylated Lex, a ligand for selectins. The differential recognition of Lewis antigens suggests differences between mSIGNR1 and DC-SIGN in the recognition of cellular ligands and pathogens that express Lewis epitopes.

Yvette Van Kooyk - One of the best experts on this subject based on the ideXlab platform.

  • the human glycoprotein salivary agglutinin inhibits the interaction of dc sign and langerin with oral micro organisms
    Journal of Innate Immunity, 2016
    Co-Authors: Martine A Boks, Sabrina T G Gunput, Ilona Kosten, A J M Ligtenberg, Sandra J Van Vliet, Susan Gibbs, Yvette Van Kooyk
    Abstract:

    Salivary agglutinin (SAG), also known as gp340 or SALSA, is a glycoprotein encoded by the Deleted in Malignant Brain Tumours 1 gene and is abundantly present in human saliva. SAG aggregates bacteria and viruses, thereby promoting their clearance from the oral cavity. The mucosa lining the oral cavity contains dendritic cells (DC) and Langerhans cells (LC), which express the C-type lectin receptors (CLR) DC-SIGN and Langerin, respectively. Both DC-SIGN and Langerin recognise mannose and fucose carbohydrate structures on pathogens and self-glycoproteins to regulate immunity and homeostasis. The purpose of this study was to investigate whether SAG interacts with these CLR and whether this interferes with the binding to oral pathogens. We show that whole parotid saliva and SAG, when coated to microplates, strongly interact with DC-SIGN and Langerin, probably via mannose and fucose structures. Also, primary human DC and LC bind parotid saliva and SAG via DC-SIGN and Langerin, respectively. Furthermore, SAG binding to DC-SIGN or Langerin prevented binding to the micro-organisms Candida albicans and Escherichia coli which express mannose and fucose-containing glycan structures. Thus, binding of saliva glycoprotein SAG to DC-SIGN and Langerin may inhibit pathogen-DC/LC interactions, and could prove to be a new immunomodulatory mechanism of SAG.

  • interactions of dc sign with mac 1 and ceacam1 regulate contact between dendritic cells and neutrophils
    FEBS Letters, 2005
    Co-Authors: Klaas P J M Van Gisbergen, Irene S. Ludwig, Teunis B. H. Geijtenbeek, Yvette Van Kooyk
    Abstract:

    Early during infection neutrophils are the most important immune cells that are involved in killing of pathogenic bacteria and regulation of innate immune responses at the site of infection. It has become clear that neutrophils also modulate adaptive immunity through interactions with dendritic cells (DCs) that are pivotal in the induction of T cell responses. Upon activation, neutrophils release TNF-α and induce maturation of DCs that enables these antigen-presenting cells to stimulate T cell proliferation and to induce T helper 1 polarization. DC maturation by neutrophils also requires cellular interactions that are mediated by binding of the DC-specific receptor DC-SIGN to Mac-1 on the neutrophil. Here, we demonstrate that also CEACAM1 is an important ligand for DC-SIGN on neutrophils. Binding of DC-SIGN to both CEACAM1 and Mac-1 is required to establish cellular interactions with neutrophils. DC-SIGN is a C-type lectin that has specificity for Lewisx, and we show that DC-SIGN mediates binding to CEACAM1 through Lewisx moieties that are specifically expressed on CEACAM1 derived from neutrophils. This indicates that glycosylation-driven binding of both Mac-1 and CEACAM1 to DC-SIGN is essential for interactions of neutrophils with DCs and enables neutrophils to modulate T cell responses through interactions with DCs.

  • lentivirus mediated rna interference of dc sign expression inhibits human immunodeficiency virus transmission from dendritic cells to t cells
    Journal of Virology, 2004
    Co-Authors: Jeanfrancois Arrighi, Teunis B. H. Geijtenbeek, Marjorie Pion, Maciej Wiznerowicz, Eduardo Garcia, Shahnaz Abraham, Florence Leuba, Valerie Dutoit, Odile Ducreyrundquist, Yvette Van Kooyk
    Abstract:

    In the early events of human immunodeficiency virus type 1 (HIV-1) infection, immature dendritic cells (DCs) expressing the DC-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) receptor capture small amounts of HIV-1 on mucosal surfaces and spread viral infection to CD4(+) T cells in lymph nodes (22, 34, 45). RNA interference has emerged as a powerful tool to gain insight into gene function. For this purpose, lentiviral vectors that express short hairpin RNA (shRNA) for the delivery of small interfering RNA (siRNA) into mammalian cells represent a powerful tool to achieve stable gene silencing. In order to interfere with DC-SIGN function, we developed shRNA-expressing lentiviral vectors capable of conditionally suppressing DC-SIGN expression. Selectivity of inhibition of human DC-SIGN and L-SIGN and chimpanzee and rhesus macaque DC-SIGN was obtained by using distinct siRNAs. Suppression of DC-SIGN expression inhibited the attachment of the gp120 envelope glycoprotein of HIV-1 to DC-SIGN transfectants, as well as transfer of HIV-1 to target cells in trans. Furthermore, shRNA-expressing lentiviral vectors were capable of efficiently suppressing DC-SIGN expression in primary human DCs. DC-SIGN-negative DCs were unable to enhance transfer of HIV-1 infectivity to T cells in trans, demonstrating an essential role for the DC-SIGN receptor in transferring infectious viral particles from DCs to T cells. The present system should have broad applications for studying the function of DC-SIGN in the pathogenesis of HIV as well as other pathogens also recognized by this receptor.

  • mycobacteria target dc sign to suppress dendritic cell function
    Journal of Experimental Medicine, 2003
    Co-Authors: Teunis B. H. Geijtenbeek, Sandra J Van Vliet, Ben J. Appelmelk, Estella A Koppel, Marta Sanchezhernandez, Christine M J E Vandenbrouckegrauls, Yvette Van Kooyk
    Abstract:

    Mycobacterium tuberculosis represents a world-wide health risk and immunosuppression is a particular problem in M. tuberculosis infections. Although macrophages are primarily infected, dendritic cells (DCs) are important in inducing cellular immune responses against M. tuberculosis. We hypothesized that DCs represent a target for M. tuberculosis and that the observed immuno-suppression results from modulation of DC functions. We demonstrate that the DC-specific C-type lectin DC-SIGN is an important receptor on DCs that captures and internalizes intact Mycobacterium bovis bacillus Calmette-Guerin (BCG) through the mycobacterial cell wall component ManLAM. Antibodies against DC-SIGN block M. bovis BCG infection of DCs. ManLAM is also secreted by M. tuberculosis-infected macrophages and has been implicated as a virulence factor. Strikingly, ManLAM binding to DC-SIGN prevents mycobacteria- or LPS-induced DC maturation. Both mycobacteria and LPS induce DC maturation through Toll-like receptor (TLR) signaling, suggesting that DC-SIGN, upon binding of ManLAM, interferes with TLR-mediated signals. Blocking antibodies against DC-SIGN reverse the ManLAM-mediated immunosuppressive effects. Our results suggest that M. tuberculosis targets DC-SIGN both to infect DCs and to down-regulate DC-mediated immune responses. Moreover, we demonstrate that DC-SIGN has a broader pathogen recognition profile than previously shown, suggesting that DC-SIGN may represent a molecular target for clinical intervention in infections other than HIV-1.

  • identification of different binding sites in the dendritic cell specific receptor dc sign for intercellular adhesion molecule 3 and hiv 1
    Journal of Biological Chemistry, 2002
    Co-Authors: Teunis B. H. Geijtenbeek, Sandra J Van Vliet, Carl G. Figdor, Gerard C F Van Duijnhoven, Elmar Krieger, Gert Vriend, Yvette Van Kooyk
    Abstract:

    The novel dendritic cell (DC)-specific human immunodeficiency virus type 1 (HIV-1) receptor DC-SIGN plays a key role in the dissemination of HIV-1 by DC. DC-SIGN is thought to capture HIV-1 at mucosal sites of entry, facilitating transport to lymphoid tissues, where DC-SIGN efficiently transmits HIV-1 to T cells. DC-SIGN is also important in the initiation of immune responses by regulating DC-T cell interactions through intercellular adhesion molecule 3 (ICAM-3). We have characterized the mechanism of ligand binding by DC-SIGN and identified the crucial amino acids involved in this process. Strikingly, the HIV-1 gp120 binding site in DC-SIGN is different from that of ICAM-3, consistent with the observation that glycosylation of gp120, in contrast to ICAM-3, is not crucial to the interaction with DC-SIGN. A specific mutation in DC-SIGN abrogated ICAM-3 binding, whereas the HIV-1 gp120 interaction was unaffected. This DC-SIGN mutant captured HIV-1 and infected T cells in trans as efficiently as wild-type DC-SIGN, demonstrating that ICAM-3 binding is not necessary for HIV-1 transmission. This study provides a basis for the design of drugs that inhibit or alter interactions of DC-SIGN with gp120 but not with ICAM-3 or vice versa and that have a therapeutic value in immunological diseases and/or HIV-1 infections.

Robert W. Doms - One of the best experts on this subject based on the ideXlab platform.

  • hepatitis c virus glycoproteins interact with dc sign and dc signr
    Journal of Virology, 2003
    Co-Authors: Stefan Pöhlmann, Frédéric Baribaud, Robert W. Doms, Jie Zhang, Zhiwei Chen, George J Leslie, George Lin, Angela Granellipiperno, Charles M Rice, Jane A Mckeating
    Abstract:

    DC-SIGN and DC-SIGNR are two closely related membrane-associated C-type lectins that bind human immunodeficiency virus (HIV) envelope glycoprotein with high affinity. Binding of HIV to cells expressing DC-SIGN or DC-SIGNR can enhance the efficiency of infection of cells coexpressing the specific HIV receptors. DC-SIGN is expressed on some dendritic cells, while DC-SIGNR is localized to certain endothelial cell populations, including hepatic sinusoidal endothelial cells. We found that soluble versions of the hepatitis C virus (HCV) E2 glycoprotein and retrovirus pseudotypes expressing chimeric forms of both HCV E1 and E2 glycoproteins bound efficiently to DC-SIGN and DC-SIGNR expressed on cell lines and primary human endothelial cells but not to other C-type lectins tested. Soluble E2 bound to immature and mature human monocyte-derived dendritic cells (MDDCs). Binding of E2 to immature MDDCs was dependent on DC-SIGN interactions, while binding to mature MDDCs was partly independent of DC-SIGN, suggesting that other cell surface molecules may mediate HCV glycoprotein interactions. HCV interactions with DC-SIGN and DC-SIGNR may contribute to the establishment or persistence of infection both by the capture and delivery of virus to the liver and by modulating dendritic cell function.

  • Expression of DC-SIGN by dendritic cells of intestinal and genital mucosae in humans and rhesus macaques.
    Journal of virology, 2002
    Co-Authors: Brian Jameson, Stefan Pöhlmann, Frédéric Baribaud, Robert W. Doms, Darlene Ghavimi, Frank Mortari, Akiko Iwasaki
    Abstract:

    To better understand the role of dendritic cells (DCs) in human immunodeficiency virus (HIV) transmission at mucosal surfaces, we examined the expressions of the HIV adhesion molecule, dendritic-cell-specific ICAM-3 grabbing nonintegrin (DC-SIGN), its closely related homologue DC-SIGNR, and HIV coreceptors by distinct DC populations in the intestinal and genital tracts of humans and rhesus macaques. We also developed monoclonal antibodies (MAbs) specific for DC-SIGN or DC-SIGNR. In the Peyer's patches, DC-SIGN expression was detected in the interfollicular regions and in clusters of cells in the subepithelial dome regions. DC-SIGN expression was not found on plasmacytoid DCs. DC-SIGNR expression was restricted to endothelial cells in approximately one-third of the capillaries in the terminal ileum. In the vaginal epithelium, Langerhans' cells did not express DC-SIGN, whereas subepithelial DCs in the lamina propria expressed moderate levels of DC-SIGN. Finally, the rectum contained cells that expressed high levels of DC-SIGN throughout the entire thickness of the mucosa, while solitary lymphoid nodules within the rectum showed very little staining for DC-SIGN. Triple-color analysis of rectal tissue indicated that CCR5+ CD4+ DC-SIGN+ DCs were localized just beneath the luminal epithelium. These findings suggest that DC-SIGN+ DCs could play a role in the transmission of primate lentiviruses in the ileum and the rectum whereas accessibility to DC-SIGN+ cells is limited in an intact vaginal mucosa. Finally, we identified a MAb that blocked simian immunodeficiency virus interactions with rhesus macaque DC-SIGN. This and other specific MAbs may be used to assess the relevance of DC-SIGN in virus transmission in vivo.

  • Constitutive and induced expression of DC-SIGN on dendritic cell and macrophage subpopulations in situ and in vitro.
    Journal of leukocyte biology, 2002
    Co-Authors: Elizabeth J. Soilleux, Robert W. Doms, George J Leslie, Lesley S. Morris, Jihed Chehimi, Qi Luo, Ernest L. Levroney, John Trowsdale, Luis J. Montaner, Drew Weissman
    Abstract:

    DC-SIGN is a C-type lectin, highly expressed on the surface of immature dendritic cells (DCs), that mediates efficient infection of T cells in trans by its ability to bind HIV-1, HIV-2, and SIV. In addition, the ability of DC-SIGN to bind adhesion molecules on surfaces of naive T cells and endothelium also suggests its involvement in T-cell activation and DC trafficking. To gain further insights into the range of expression and potential functions of DC-SIGN, we performed a detailed analysis of DC-SIGN expression in adult and fetal tissues and also analyzed its regulated expression on cultured DCs and macrophages. First, we show that DC-SIGN expression is restricted to subsets of immature DCs in tissues and on specialized macrophages in the placenta and lung. There were no overt differences between DC-SIGN expression in adult and fetal tissues except that DC-SIGN expression in alveolar macrophages was only present after birth. Similarly, in tissues, DC-SIGN was observed primarily on immature (CD83-negative) DCs. Secondly, in the peripheral blood, we found expression of DC-SIGN on a small subset of BDCA-2+ plasmacytoid DC precursors (pDC2), concordant with our finding of large numbers of DC-SIGN-positive cells in allergic nasal polyps (previously shown to be infiltrated by DC2). Triple-label confocal microscopy indicated that DC-SIGN was colocalized with BDCA-2 and CD123 on DCs in nasal polyp tissue. Consistent with this finding is our observation that DC-SIGN can be up-regulated on monocyte-derived macrophages upon exposure to the Th2 cytokine, IL-13. In summary, our data demonstrate the relevant populations of DC and macrophages that express DC-SIGN in vivo where it may impact the efficiency of virus infection and indicate that DC-SIGN expression may be involved in the Th2 axis of immunity.

  • Placental expression of DC-SIGN may mediate intrauterine vertical transmission of HIV
    The Journal of pathology, 2001
    Co-Authors: Elizabeth J. Soilleux, Stefan Pöhlmann, Robert W. Doms, Lesley S. Morris, John Trowsdale, Benhur Lee, Nicholas Coleman
    Abstract:

    Mechanisms of transplacental transmission of human immunodeficiency virus (HIV) are poorly understood. DC-SIGN is a C-type lectin able to bind HIV gp120 with high affinity, mediating HIV adsorption to the surface of dendritic cells for up to several days. Via this mechanism, DC-SIGN significantly enhances the infection of CD4+ co-receptor (CCR5 or CXCR4)+ T lymphocytes in trans. In this study, DC-SIGN-specific serum was developed to investigate the cell type responsible for the high level of DC-SIGN RNA expression previously observed in the placenta. DC-SIGN expression was shown on CD68+ HLA-II+ CD14low S100+/− CD83− CD86− cmrf-44− villous cells consistent with Hofbauer cells and also on CD68+ HLA-II+ CD14high S100− CD83− CD86− cmrf-44− decidual macrophages. The DC-SIGN+ Hofbauer cells co-express CD4 and the chemokine receptors, CCR5 and CXCR4, observations which may account for the ability of these cells to become infected with HIV. These fetal DC-SIGN+ cells are separated by only a layer of trophoblast from both DC-SIGN+ maternal cells and maternal blood, potential sources of HIV in infected mothers. Previous studies have suggested that this trophoblast layer is frequently breached during pregnancy. It is therefore proposed that DC-SIGN may facilitate the transplacental transmission of HIV. Copyright © 2001 John Wiley & Sons, Ltd.

  • dc sign interactions with human immunodeficiency virus type 1 and 2 and simian immunodeficiency virus
    Journal of Virology, 2001
    Co-Authors: Stefan Pöhlmann, Frédéric Baribaud, George J Leslie, Melissa D Sanchez, Kirsten Hiebenthalmillow, Jan Munch, Frank Kirchhoff, Robert W. Doms
    Abstract:

    Dendritic cells (DCs) efficiently bind and transmit human immunodeficiency virus (HIV) to cocultured T cells and so may play an important role in HIV transmission. DC-SIGN, a novel C-type lectin that is expressed in DCs, has recently been shown to bind R5 HIV type 1 (HIV-1) strains and a laboratory-adapted X4 strain. To characterize the interaction of DC-SIGN with primate lentiviruses, we investigated the structural determinants of DC-SIGN required for virus binding and transmission to permissive cells. We constructed a panel of DC-SIGN mutants and established conditions which allowed comparable cell surface expression of all mutants. We found that R5, X4, and R5X4 HIV-1 isolates as well as simian immunodeficiency and HIV-2 strains bound to DC-SIGN and could be transmitted to CD4/coreceptor-positive cell types. DC-SIGN contains a single N-linked carbohydrate chain that is important for efficient cell surface expression but is not required for DC-SIGN-mediated virus binding and transmission. In contrast, C-terminal deletions removing either the lectin binding domain or the repeat region abrogated DC-SIGN function. Trypsin-EDTA treatment inhibited DC-SIGN mediated infection, indicating that virus was maintained at the surface of the DC-SIGN-expressing cells used in this study. Finally, quantitative fluorescence-activated cell sorting analysis of AU1-tagged DC-SIGN revealed that the efficiency of virus transmission was strongly affected by variations in DC-SIGN expression levels. Thus, variations in DC-SIGN expression levels on DCs could greatly affect the susceptibility of human individuals to HIV infection.

Carl G. Figdor - One of the best experts on this subject based on the ideXlab platform.

  • Relevance of DC-SIGN in DC-induced T cell proliferation.
    Journal of leukocyte biology, 2006
    Co-Authors: Karlijn Gijzen, Paul J. Tacken, Aukje W. Zimmerman, Ben Joosten, I. Jolanda M. De Vries, Carl G. Figdor, Ruurd Torensma
    Abstract:

    The role of dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) in DC-T cell communication was assessed by analyzing the effect of DC-SIGN-blocking mAb in MLR. The results show that the degree of inhibition by DC-SIGN and LFA-1 mAb depends on the magnitude of the MLR and the maturation status of the DC. Addition of DC-SIGN mAb at several time-points during MLR showed that DC-SIGN is involved early on in DC-T cell contacts. This initial role is masked by strong adhesive and costimulatory mechanisms, indicating a short-lived effect of DC-SIGN in DC-T cell interactions. To examine this concept in more detail, the percentage of PBL capable of binding DC-SIGN was determined. Analysis of several donors revealed that 1-20% PBL bind to beads coated with recombinant DC-SIGN, and the DC-SIGN-binding cells comprised all major cell subsets found in blood. PBL isolated from a donor with high DC-SIGN-binding capacity were more prone to blocking by DC-SIGN mAb in MLR than PBL from a donor with low DC-SIGN-binding capacity. This study indicates an initial and transient role for DC-SIGN in T cell proliferation, which becomes apparent when T cell proliferation is low and when the percentage of DC-SIGN binding PBL is high.

  • the c type lectin dc sign cd209 is an antigen uptake receptor for candida albicans on dendritic cells
    European Journal of Immunology, 2003
    Co-Authors: Alessandra Cambi, Karlijn Gijzen, Ben Joosten, Ruurd Torensma, Jolanda I M De Vries, Gosse J Adema, Mihai G Netea, Bart Jan Kullberg, Luigina Romani, Carl G. Figdor
    Abstract:

    Dendritic cells (DC) that express the type II C-type lectin DC-SIGN (CD209) are located in the submucosa of tissues, where they mediate HIV-1 entry. Interestingly, the pathogen Candida albicans, the major cause of hospital-acquired fungal infections, penetrates at similar submucosal sites. Here we demonstrate that DC-SIGN is able to bind C. albicans both in DC-SIGN-transfected cell lines and in human monocyte-derived DC. The binding was shown to be time- as well as concentration-dependent, and live as well as heat-inactivated C. albicans were bound to the same extent. Moreover, in immature DC, DC-SIGN was able to internalize C. albicans in specific DC-SIGN-enriched vesicles, distinct from those containing the mannose receptor, the other known C. albicans receptor expressed by DC. Together, these results demonstrate that DC-SIGN is an exquisite pathogen-uptake receptor that captures not only viruses but also fungi.

  • identification of different binding sites in the dendritic cell specific receptor dc sign for intercellular adhesion molecule 3 and hiv 1
    Journal of Biological Chemistry, 2002
    Co-Authors: Teunis B. H. Geijtenbeek, Sandra J Van Vliet, Carl G. Figdor, Gerard C F Van Duijnhoven, Elmar Krieger, Gert Vriend, Yvette Van Kooyk
    Abstract:

    The novel dendritic cell (DC)-specific human immunodeficiency virus type 1 (HIV-1) receptor DC-SIGN plays a key role in the dissemination of HIV-1 by DC. DC-SIGN is thought to capture HIV-1 at mucosal sites of entry, facilitating transport to lymphoid tissues, where DC-SIGN efficiently transmits HIV-1 to T cells. DC-SIGN is also important in the initiation of immune responses by regulating DC-T cell interactions through intercellular adhesion molecule 3 (ICAM-3). We have characterized the mechanism of ligand binding by DC-SIGN and identified the crucial amino acids involved in this process. Strikingly, the HIV-1 gp120 binding site in DC-SIGN is different from that of ICAM-3, consistent with the observation that glycosylation of gp120, in contrast to ICAM-3, is not crucial to the interaction with DC-SIGN. A specific mutation in DC-SIGN abrogated ICAM-3 binding, whereas the HIV-1 gp120 interaction was unaffected. This DC-SIGN mutant captured HIV-1 and infected T cells in trans as efficiently as wild-type DC-SIGN, demonstrating that ICAM-3 binding is not necessary for HIV-1 transmission. This study provides a basis for the design of drugs that inhibit or alter interactions of DC-SIGN with gp120 but not with ICAM-3 or vice versa and that have a therapeutic value in immunological diseases and/or HIV-1 infections.

  • the dendritic cell specific adhesion receptor dc sign internalizes antigen for presentation to t cells
    Journal of Immunology, 2002
    Co-Authors: Anneke Engering, Sandra J Van Vliet, Carl G. Figdor, Teunis B. H. Geijtenbeek, Mietske Wijers, Ellis Van Liempt, Nicolas Demaurex, Antonio Lanzavecchia, Jack A M Fransen, Vincent Piguet
    Abstract:

    Dendritic cells (DCs) capture Ags or viruses in peripheral tissue to transport them to lymphoid organs to induce cellular T cell responses. Recently, a DC-specific C-type lectin was identified, DC-specific ICAM-grabbing non-integrin (DC-SIGN), that functions as cell adhesion receptor mediating both DC migration and T cell activation. DC-SIGN also functions as an HIV-1R that captures HIVgp120 and facilitates DC-induced HIV transmission of T cells. Internalization motifs in the cytoplasmic tail of DC-SIGN hint to a function of DC-SIGN as endocytic receptor. In this study we demonstrate that on DCs DC-SIGN is rapidly internalized upon binding of soluble ligand. Mutating a putative internalization motif in the cytoplasmic tail reduces ligand-induced internalization. Detailed analysis using ratio fluorescence imaging and electron microscopy showed that DC-SIGN-ligand complexes are targeted to late endosomes/lysosomes. Moreover, ligands internalized by DC-SIGN are efficiently processed and presented to CD4+ T cells. The distinct pattern of expression of C-type lectins on DCs in situ and their nonoverlapping Ag recognition profile hint to selective functions of these receptors to allow a DC to recognize a wide variety of Ags and to process these to induce T cell activation. These data point to a novel function of the adhesion receptor DC-SIGN as an efficient DC-specific Ag receptor that can be used as a target to induce viral and antitumor immunity.

  • identification of dc sign a novel dendritic cell specific icam 3 receptor that supports primary immune responses
    Cell, 2000
    Co-Authors: T.b.h. Geijtenbeek, G.c.f. Van Duijnhoven, S.j. Van Vliet, Y. Van Kooyk, Ruurd Torensma, G J Adema, Carl G. Figdor
    Abstract:

    Contact between dendritic cells (DC) and resting T cells is essential to initiate a primary immune response. Here, we demonstrate that ICAM-3 expressed by resting T cells is important in this first contact with DC. We discovered that instead of the common ICAM-3 receptors LFA-1 and alphaDbeta2, a novel DC-specific C-type lectin, DC-SIGN, binds ICAM-3 with high affinity. DC-SIGN, which is abundantly expressed by DC both in vitro and in vivo, mediates transient adhesion with T cells. Since antibodies against DC-SIGN inhibit DC-induced proliferation of resting T cells, our findings predict that DC-SIGN enables T cell receptor engagement by stabilization of the DC-T cell contact zone.