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CpG Oligodeoxynucleotides (cpg + oligodeoxynucleotide)
Selected AbstractsCpG oligodeoxynucleotides protect mice from lethal challenge with Candida albicans via a pathway involving tumor necrosis factor-,-dependent interleukin-12 inductionFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2007Jung-Hwa Choi Abstract In this study, we have attempted to determine whether the systemic administration of CpG oligodeoxynucleotide (CpG-ODN) 1826 would protect mice against systemic lethal Candida albicans infection. CpG-ODNs were found completely to protect mice from death and also reduced the growth of C. albicans in the kidneys. The administration of CpG-ODNs resulted in early interleukin (IL)-12 mRNA expression in the kidneys and an increase in serum IL-12 levels. The protective activity of CpG-ODN was abolished in IL-12-deficient (IL-12,/,) mice, thereby indicating the IL-12-dependency inherent to the effects of CpG-ODN. The protective effect of CpG-ODN was not associated with the activity of NF-,B. Interestingly, in tumor necrosis factor (TNF)-,-deficient (TNF,/,) mice CpG-ODN neither exerted protective effects nor induced IL-12 expression. These data indicate that CpG-ODN protects animals against lethal C. albicans challenge via a pathway that involves the TNF-,-dependent induction of IL-12. [source] Development and Evaluation of a DNA Vaccine Based on Helicobacter pylori urease B: Failure to Prevent Experimental Infection in the Mouse ModelHELICOBACTER, Issue 6 2006Livania Zavala-Spinetti Abstract Background:, The development of a vaccine against Helicobacter pylori has become a priority to prevent major morbidity and mortality associated with this infection. Our goal was to prepare and evaluate a DNA vaccine based on the urease B gene (ureB). Methods:, The ureB gene of H. pylori was amplified and cloned into the eukaryotic expression vector pcDNA3.1/TOPO. Plasmid DNA was purified from transformed Escherichia coli cells and used to immunize mice by the intragastric, intramuscular, intrarectal (40 µg each) and intranasal (16 µg) route, three doses every 2 weeks, with CpG oligodeoxynucleotide (ODN) as adjuvant. Four weeks after the third dose, animals were orally challenged with Helicobacter felis and were sacrificed 6 weeks later. The stomach was stained to detect the presence of infection. Results:, Despite in vitro confirmation of successful cloning and functionality of the ureB gene with expression of a protein morphologically and antigenically identical to urease B, the DNA vaccine did not perform well in vivo. Immunization of mice produced a weak immune response. Overall, intrarectal and intranasal administration seemed more immunogenic than other routes. Protection against challenge was modest and nonsignificant, and slightly better on animals immunized by the intramuscular and intranasal route. Conclusion:, A DNA vaccine based on H. pylori urease B was poorly immunogenic and nonprotective at the conditions evaluated. Higher doses, better adjuvants or a prime-boost approach may circumvent these limitations. [source] Rapid and reliable generation of invariant natural killer T-cell lines in vitroIMMUNOLOGY, Issue 3 2009Asako Chiba Summary Several tools have proved useful in the study of invariant natural killer T (iNKT) cells, including CD1d-deficient mice, J,281-deficient mice, synthetic lipid antigens and antigen-loaded CD1d tetramers. However, the generation and examination of long-term primary murine iNKT cell lines in vitro has been challenging. Here, we show the rapid generation of iNKT cell lines from splenic iNKT cells of V,14 T-cell receptor (TCR) transgenic (Tg) mice. These purified iNKT cells were stimulated by bone marrow-derived dendritic cells (BMDCs) loaded with ,-galactosylceramide (,GalCer) and cultured with interleukin (IL)-2 and IL-7. iNKT cells proliferated dramatically, and the cell number exhibited a 100-fold increase within 2 weeks and a 105 -fold increase in 8 weeks after repeated stimulation with ,GalCer. The iNKT cell lines consisted of iNKT cells expressing V, chains including V,8.1/8.2, V,14, V,10, V,6 and V,7, and responded to stimulation with ,GalCer presented both by BMDCs and by plate-bound CD1d. In addition, the iNKT cell lines produced interferon (IFN)-, when activated by lipopolysaccharide (LPS) or CpG oligodeoxynucleotide (ODN)-stimulated BMDCs. Further, we show that iNKT cell lines produced cytokines in response to microbial antigens. In summary, high-yield iNKT cell lines were generated very rapidly and robustly expanded, and these iNKT cells responded to both TCR and cytokine stimulation in vitro. Given the desire to study primary iNKT cells for many purposes, these iNKT cell lines should provide an important tool for the study of iNKT cell subsets, antigen and TCR specificity, activation, inactivation and effector functions. [source] H2-Dd -mediated upregulation of interleukin-4 production by natural killer T-cell and dendritic cell interactionIMMUNOLOGY, Issue 1 2008Kazuomi Mizuuchi Summary Natural killer T (NKT) cells are capable of subserving apparently opposite functions, the interferon-, (IFN-,)-mediated enhancement of host defence and interleukin-4 (IL-4) -mediated immune regulation. Although dendritic cells (DCs) potently activate NKT cells, DC regulation of the IL-4,IFN-, balance via NKT-cell activation is not well characterized. In the present study, we examined the effect of DC treatment with CpG oligodeoxynucleotide (ODN), a Toll-like receptor 9 ligand, on the induction of NKT-cell cytokine production. CpG-ODN-conditioned and ,-galactosylceramide (,-GalCer)-loaded myeloid DCs (CpG-DCs) from BALB/c mice showed enhanced ability to induce NKT-cell production of IL-4, but not IFN-,, compared to ,-GalCer-loaded control DCs (not treated with CpG-ODN). The CpG-DCs expressed significantly higher levels of H2-Dd than control DCs, and blocking of the H2-Dd and Ly49 receptor interaction during antigen presentation completely abolished the enhanced ability of the CpG-DCs to induce NKT-cell production of IL-4. These findings demonstrate that DC recognition of the CpG motif leads to induction of enhanced IL-4 production by NKT cells via interaction of the augmented H2-Dd with Ly49 receptors on NKT cells. [source] Innate immune responses induced by CpG oligodeoxyribonucleotide stimulation of ovine blood mononuclear cellsIMMUNOLOGY, Issue 2 2003Angelo Mena Summary Examples exist in the literature that demonstrate that treatment with immunostimulatory cytosine,phosphate,guanosine (CpG)-DNA can protect mice against infection by intracellular pathogens. There are, however, few studies reporting that CpG-DNA offers similar disease protection in other species. In this study, we assessed the potential of a class A and class B CpG oligodeoxynucleotide (ODN) to induce innate immune responses in sheep, an outbred species. Using peripheral blood mononuclear cells, we have for the first time demonstrated CpG-ODN-induced innate immune responses, including natural-killer-like activity [non-major histocompatibility complex (MHC)-restricted cytotoxicity], interferon-, secretion and 2,-5,A oligoadenylate synthetase activity, that could contribute to immune protection in sheep. The type and magnitude of these responses were dependent on ODN class and non-MHC-restricted killing was not associated with interferon-, production. The latter observation is in contrast with observations reported for mice and humans. These observations support the conclusion that differences in CpG-ODN-induced responses exist among species and that specific ODN sequences can significantly influence innate immune responses. [source] CpG ODN enhance antigen-specific NKT cell activation via plasmacytoid dendritic cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2005Anja Marschner Abstract Human V,24+ V,11+ natural killer T cells (NKT cells) are "natural memory" T cells that detect glycolipid antigens such as ,-galactosylceramide (,-GalCer) presented on CD1d. In the present study we found that highly purified V,24+ NKT cells lack TLR9 mRNA, and thus are not sensitive towards stimulation with CpG oligodeoxynucleotides (ODN). Within PBMC, however, CpG ODN synergistically activated NKT cells stimulated with their cognate antigen ,-GalCer. Depletion of plasmacytoid dendritic cells (PDC) or myeloid dendritic cells (MDC) revealed that both DC subsets were necessary for the synergistic activation of NKT cells by ,-GalCer and CpG ODN. While PDC were responsible for the stimulation of NKT cells with CpG ODN, MDC but not PDC presented ,-GalCer via CD1d. Partial activation of NKT cells was mediated by PDC-derived IFN-,, whereas full activation of NKT cells as indicated by IFN,, production required cell-to-cell contact of PDC and NKT cells in addition to IFN-,; OX40 was involved in this interaction. We conclude that CpG-activated PDC enhance ,-GalCer-specific NKT cell activation, and bias activated NKT cells towards a Th1 phenotype. Our results lead to a novel concept of PDC function: to regulate effector activity of antigen-stimulated T cells in a cell contact-dependent manner without the need of simultaneous presentation of the cognate T cell antigen. [source] Murine thymic plasmacytoid dendritic cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 4 2003Tomoyuki Okada Abstract We report herein heterogeneous murine thymic cell subsets expressing CD11c and B220 (CD45R). The CD11c+B220+ subset expresses Ly6Chigh and MHC class IIlow in contrast with previously described thymic DC (CD11c+B220, cells). Freshly isolated thymic CD11c+B220+ cells show typical plasmacytoid morphology which differentiates to mature DC, in vitro with CpG oligodeoxynucleotides (ODN) 2216; we term this subset thymic plasmacytoid DC (pDC). These thymic pDC are highly sensitive to spontaneous apoptosis in vitro and induce low T cell allo-proliferation activity. Thymic pDC express low TLR2, TLR3 and TLR4 mRNA, normally found on human immature DC, and high TLR7 and TLR9 mRNA, normally found on human pDC. Thymic pDC also produce high amounts of IFN-, following culture with CpG ODN 2216 (TLR9 ligands) as compared with the previously defined thymic DC lineage which expresses low TLR9 mRNA and produce high IL-12 (p40) with CpG ODN 2216. These results indicate that thymic pDC are similar to IFN-producing cells as well as human pDC. The TLR and cytokine production profiles are consistent with a nomenclature of pDC. The repertoire of this cell lineage to TLR9 ligands demonstrate that such responses are determined not only by the quantity of expression, but also cell lineage. [source] CpG oligodeoxynucleotides protect mice from lethal challenge with Candida albicans via a pathway involving tumor necrosis factor-,-dependent interleukin-12 inductionFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2007Jung-Hwa Choi Abstract In this study, we have attempted to determine whether the systemic administration of CpG oligodeoxynucleotide (CpG-ODN) 1826 would protect mice against systemic lethal Candida albicans infection. CpG-ODNs were found completely to protect mice from death and also reduced the growth of C. albicans in the kidneys. The administration of CpG-ODNs resulted in early interleukin (IL)-12 mRNA expression in the kidneys and an increase in serum IL-12 levels. The protective activity of CpG-ODN was abolished in IL-12-deficient (IL-12,/,) mice, thereby indicating the IL-12-dependency inherent to the effects of CpG-ODN. The protective effect of CpG-ODN was not associated with the activity of NF-,B. Interestingly, in tumor necrosis factor (TNF)-,-deficient (TNF,/,) mice CpG-ODN neither exerted protective effects nor induced IL-12 expression. These data indicate that CpG-ODN protects animals against lethal C. albicans challenge via a pathway that involves the TNF-,-dependent induction of IL-12. [source] Functional alterations of liver innate immunity of mice with aging in response to CpG-oligodeoxynucleotide,HEPATOLOGY, Issue 5 2008Toshinobu Kawabata Immune functions of liver natural killer T (NKT) cells induced by the synthetic ligand ,-galactosylceramide enhanced age-dependently; hepatic injury and multiorgan dysfunction syndrome (MODS) induced by ligand-activated NKT cells were also enhanced. This study investigated how aging affects liver innate immunity after common bacteria DNA stimulation. Young (6 weeks) and old (50-60 weeks) C57BL/6 mice were injected with CpG oligodeoxynucleotides (CpG-ODN), and the functions of liver leukocytes were assessed. A CpG-ODN injection into the old mice remarkably increased tumor necrosis factor (TNF) production in Kupffer cells, and MODS and lethal shock were induced, both of which are rarely seen in young mice. Old Kupffer cells showed increased Toll-like receptor-9 expression, and CpG-ODN challenge augmented TNF receptor and Fas-L expression in liver NKT cells. Experiments using mice depleted of natural killer (NK) cells by anti-asialoGM1 antibody (Ab), perforin knockout mice, and mice pretreated with neutralizing interferon (IFN)-, Ab demonstrated the important role of liver NK cells in antitumor immunity. The production capacities of old mice for IFN-,, IFN-,, and perforin were much lower than those of young mice, and the CpG-induced antitumor cytotoxicity of liver NK cells lessened. Lethal shock and MODS greatly decreased in old mice depleted/deficient in TNF, FasL, or NKT cells. However, depletion of NK cells also decreased serum TNF levels and FasL expression of NKT cells, which resulted in improved hepatic injury and survival, suggesting that NK cells are indirectly involved in MODS/lethal shock induced by NKT cells. Neutralization of TNF did not reduce the CpG-induced antitumor effect in the liver. Conclusion: Hepatic injury and MODS mediated by NKT cells via the TNF and FasL-mediated pathway after CpG injection increased, but the antitumor activity of liver NK cells decreased with aging. (HEPATOLOGY 2008.) [source] Adjuvant effects of CpG oligodeoxynucleotides on responses against T-independent type 2 antigensIMMUNOLOGY, Issue 1 2001J. Kovarik Summary Oligodeoxynucleotides containing CpG motifs (CpG-ODN) are potent in vitro B-cell activators and they have been successfully used to increase in vivo antibody responses to T-dependent peptide and protein antigens. In contrast, the use of CpG-ODN to enhance in vivo antibody responses to various T-independent type 2 (TI-2) antigens has recently generated contradictory results. In this study, we compared the CpG-ODN stimulatory effect on antibody responses of adult and young BALB/c mice to trinitrophenylaminoethyl-carboxymethyl (TNP) -Ficoll and to polysaccharides (PS) from several distinct serotypes of Streptococcus pneumoniae (SPn). CpG-ODN co-administration significantly enhanced antigen-specific immunoglobulin M (IgM), IgG, IgG1 and IgG2a titres to TNP-Ficoll. The depletion of CD4+ cells by monclonal antibodies (GK1.5) identified their essential role in CpG-ODN-mediated enhancement of antibody responses. In contrast to TNP-Ficoll, CpG-ODN failed to enhance IgM and IgG responses to any of the 18 SPnPS serotypes tested. Providing T-cell epitopes by the conjugation of SPnPS to the carrier protein tetanus toxoid again allowed CpG-ODN to mediate enhancement of IgG, IgG2a and IgG3 responses to most SPnPS serotypes. Thus, antigen-presenting cell/T-cell interaction appears to largely mediate the in vivo influence of CpG-ODN on antibody responses to TI-2 antigens. In early life, additional factors limit CpG-ODN modulation of antibody responses to TI-2 antigens. [source] CpG oligodeoxynucleotides accelerate reovirus type 2-triggered insulitis in DBA/1 suckling miceINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 5 2002T. Hayashi Summary. We reported previously that reovirus type-2 (Reo-2) triggers T-helper (Th) 1-mediated autoimmune insulitis resulting in temporal impaired glucose tolerance (IGT) approximately 10 days post infection (d.p.i) in suckling DBA/1 mice. We hypothesized that CpG motifs in bacteria may enhance virus-induced insulitis through its content of unmethylated CpG motifs. In the infected mice, the intraperitoneal treatment of synthetic 20-base oligodeoxynucleotides with CpG motifs (CpG ODN) caused increase in cumulative incidence of insulitis with IGT, increased serum interferon (IFN)-, concentration, and high frequency of autoantibody against pancreatic islet cells, compared to the infected mice without CpG ODN at 17 d.p.i. Also CD4+ and CD8+ lymphocytes infiltrated in and/or around pancreatic islets in the CpG ODN-treated mice. This evidence suggests that CpG ODN may contribute to accelerate Reo-2-induced autoimmune reaction against pancreatic islet cells via additional effects of Th1 cytokines especially IFN-,. [source] Oral immunization with Porphyromonas gingivalis outer membrane protein and CpG oligodeoxynucleotides elicits T helper 1 and 2 cytokines for enhanced protective immunityMOLECULAR ORAL MICROBIOLOGY, Issue 3 2010C. Liu Summary The aim of this study was to evaluate the efficacy of an oral vaccine containing the 40-kDa outer membrane protein of Porphyromonas gingivalis (40K-OMP) and synthetic oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) to control oral infection by P. gingivalis. Oral immunization with 40K-OMP plus CpG ODN induced significant 40K-OMP-specific serum immunoglobulin G (IgG), IgA, and saliva IgA antibody responses. The 40K-OMP-specific CD4+ T cells induced by oral 40K-OMP plus CpG ODN produced both T helper type 1 (Th1; interferon-,) and Th2 (interleukin-4) cytokines. Furthermore, increased frequencies of CD11c+ B220+ dendritic cells (DCs) and CD11c+ CD11b+ DCs with upregulated expression of CD80, CD86, CD40, and major histocompatibility complex class II molecules were noted in spleen, Peyer's patches, and cervical lymph nodes. Immunized mice were then infected orally with P. gingivalis to determine whether the immune responses induced by oral 40K-OMP plus CpG ODN were capable of suppressing the bone resorption caused by P. gingivalis infection. Mice given 40K-OMP plus CpG ODN showed significantly reduced bone loss associated with oral infection by P. gingivalis. Oral administration of 40K-OMP together with CpG ODN induces Th1-type and Th2-type cells, which provide help for protective immunity against P. gingivalis infection. This may be an important tool for the prevention of chronic periodontitis. [source] The effects of CpG-C oligodeoxynucleotides on innate immune responses in Eriocheir sinensis (H. Milne-Edwards, 1853)AQUACULTURE RESEARCH, Issue 10 2010Ying Zhang Abstract CpG oligodeoxynucleotides (ODNs) can stimulate the immune system, and therefore are widely used as a therapeutic vaccination and immune adjuvant in human. In the present study, CpG-C, a combination of A- and B-class ODN, was injected into Chinese mitten crab Eriocheir sinensis at three doses (0.1, 1 and 10 ,g crab,1), and the reactive oxygen species (ROS) levels, activities of total intracellular phenoloxidase (PO) and lysozyme-like activities, the mRNA transcripts of EsproPO, EsCrustin and EsALF were assayed to evaluate its modulating effects on the immune system of crab. The ROS levels in all treated and control groups were significantly increased from 6 to 24 h, except that ROS in 0.1 ,g CpG-C-treated crabs was comparable to that of the blank at 6 h. The PO activity was significantly enhanced and EsproPO transcripts were down-regulated (P<0.01) at 6 h after the injection of 0.1 ,g CpG-C, with no significant changes in the other dosage treatments. The lysozyme-like activities and EsCrustin transcripts in the CpG-C-treatment groups were significantly higher than those of controls. The mRNA expression of EsALF remained almost constant in all the groups during the treatment. These results collectively suggested that CpG-C could activate the immune responses of E. sinensis, and might be used as a novel immunostimulant for disease control in crabs. [source] Use of A-type CpG oligodeoxynucleotides as an adjuvant in allergen-specific immunotherapy in humans: a phase I/IIa clinical trialCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2009G. Senti Summary Background B-type CpG oligodeoxynucleotides (ODN) is currently used in clinical trials because of its prolonged half,life, which is due to its phosphorothioate backbone. A-type CpG ODN is a stronger inducer of IFN but has an unstable phosphodiester backbone that has so far prohibited its clinical use. However, upon association with virus-like particles (VLP) consisting of the bacteriophage Q, coat protein, A-type CpG ODN can be stabilized and can become an efficient adjuvant in mice. Therefore, the phase I/IIa study presented represents the first test of A-type CpGs in humans. Objective To test the safety, tolerability and clinical efficacy of QbG10 as an adjuvant for subcutaneous immunotherapy with a house dust mite (HDM) allergen extract in allergic patients. Methods A single centre, open-label phase I/IIa study evaluated the safety, tolerability and clinical efficacy of QbG10 as an adjuvant to immunotherapy with a subcutaneous HMD allergen extract in 20 patients suffering from HDM allergy. Twenty-one patients were enrolled between March and July 2005. Individual immunotherapy lasted 10 weeks. Clinical end-points included questionnaires, conjunctival provocation, skin prick tests and the measurement of allergen-specific IgG and IgE. Results QbG10 was well tolerated. Almost complete tolerance to the allergen was observed in conjunctival provocation testing after treatment with QbG10, and symptoms of rhinitis and allergic asthma were significantly reduced. Within 10 weeks of therapy, patients were nearly symptom-free and this amelioration lasted for at least 38 weeks post-treatment. Following injections of QbG10 and HDM allergen extract, allergen-specific IgG increased, while there was a transient increase in allergen-specific IgE titres. Skin reactivity to HDM was reduced. Conclusion The subcutaneous application of HDM allergen, together with A-type CpG ODN packaged into VLP, was safe. All patients achieved practically complete alleviation of allergy symptoms after 10 weeks of immunotherapy. This promising clinical outcome calls for larger placebo-controlled phase II studies. [source] | ||||||||||||||||||||||