Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capacity of pertussis toxin (PT) to induce maturation and functional activities of human monocyte-derived dendritic cells (DCs) was investigated. Both native PT (nPT) and genetically detoxified PT (dPT) efficiently promoted expression on DCs of CD80, CD86, human leukocyte antigen-DR, and CD83 markers, alloreactive antigen presentation, and cytokine production, primarily interferon (IFN)-gamma. Although they did not affect interleukin (IL)-10 production by lipopolysaccharide (LPS)-stimulated DCs, both nPT and dPT strongly synergized with LPS for IL-12 production. PTs plus LPS-stimulated DCs secreted soluble factors fostering IFN-gamma but not IL-4 and IL-5 production by naive T cells. T helper type 1 (Th1) polarization was, as alloreactive antigen presentation, inhibited by anti-IL-12 monoclonal antibody. These findings support the notion that nPT, in addition to inducing specific immune response, is a potent Th1 adjuvant and that dPT fully preserves this adjuvanticity. The synergic interaction between PT and LPS in IL-12 production might be relevant for the mechanisms of vaccine-induced protection.
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PMID:Native and genetically inactivated pertussis toxins induce human dendritic cell maturation and synergize with lipopolysaccharide in promoting T helper type 1 responses. 1213 31

Virgin T cells being primed to Th2-inducing or Th1-inducing Ags, respectively, start to synthesize IL-4 or IFN-gamma as they begin to proliferate. Parallel respective induction of B cells to produce gamma1 or gamma2a switch transcripts provides additional evidence of early divergent Th activity. This report concerns the roles of IL-4, IL-13, and B cells in these early events in vivo. Th2 responses were induced in lymph nodes against hapten-protein given s.c. with killed Bordetella pertussis adjuvant. In T cell proliferation in wild-type mice, IL-4 message up-regulation and gamma1 and epsilon switch transcript production were underway 48-72 h after immunization. The absence of IL-4, IL-13, or B cells did not alter the early T cell proliferative response. The gamma1 and epsilon switch transcript production was still induced in the absence of IL-4, IL-13, or both, but at a reduced level, while the dominance of switching to IgG1 in the extrafollicular hapten-specific plasma cell response was retained. The up-regulation of IL-4 message was not reduced or delayed in the absence of B cells and was only marginally reduced by the absence of IL-13. It is concluded that signals delivered by dendritic cells, which are not dependent on the presence of IL-4, IL-13, or B cells, can prime virgin T cells and induce the early Th2 activities studied. These early events that direct virgin T cells toward Th2 differentiation contrast with the critical later role of Th2 cytokines in selectively expanding Th2 clones and driving further IL-4 synthesis.
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PMID:Th2 activities induced during virgin T cell priming in the absence of IL-4, IL-13, and B cells. 1221 3

Experimental autoimmune encephalomyelitis (EAE) is an animal model of human multiple sclerosis that requires the activation of autoreactive T cells for the expression of pathology. EAE has been most frequently studied in the Lewis rat model as well as in several murine models of EAE including the PLJ and B10PL strains. In the present study we describe a novel model of EAE induced in the Wistar rat strain by immunization with guinea pig spinal cord antigens and pertussis toxin (PT). T cell responses were induced to myelin basic protein. Autoreactive T cells could be totally blocked by the in vitro treatment with CTLA4Ig, a protein that blocks the costimulation of autoreactive T cells. The addition of IL-2 could reverse the inhibition seen in vitro with CTLA4Ig. The effects of inhibition of B7 costimulation were also examined by an analysis of cytokine responses and IL-2 receptor on T cells. CTLA4Ig treatment in vitro reduced the expression of IL-2 receptor on T cells, enhanced T cell apoptosis and decreased the synthesis of IL-2, IFN-gamma and TNF-alpha. CTLA4Ig treatment had no effect on IL-10 synthesis by T cells, a cytokine implicated in the functions of regulatory T cell subsets. Overall, our studies support the rationale of B7 blocking therapies as a potential treatment for models of multiple sclerosis. The induction of EAE in the Wistar rat provides yet another novel model in which to examine the regulation of T cell autoimmunity.
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PMID:Experimental autoimmune encephalomyelitis in the Wistar rat: dependence of MBP-specific T cell responsiveness on B7 costimulation. 1238 44

Accumulating evidence indicates that monocyte chemoattractant protein-1 (MCP-1), a CC chemokine, also displays immunoregulatory functions and may be involved in Th subset differentiation. In this study, we examined the effects of MCP-1 on the cytokine-driven differentiation of monocytes into dendritic cells (DCs), the most potent APCs for naive T cells. We found that DCs generated in the presence of MCP-1 displayed a markedly reduced production of IL-12 in response to CD40 ligand but not in response to Staphylococcus aureus stimulation in the presence or absence of IFN-gamma. The production of IL-10, a potent endogenous IL-12 inhibitor, was not affected by MCP-1. Whereas the inhibitory activity of MCP-1 on IL-12 production by monocytes was sensitive to pertussis toxin, its effects on DC differentiation were pertussis toxin resistant. MCP-1 did not affect the surface phenotype and T cell-stimulating activity of DCs, but most interestingly, naive T cells stimulated with MCP-1-primed DCs produced much less IFN-gamma but the same levels of IL-13. Taken together, our results indicated that MCP-1 modulates the differentiation of monocytes into DCs and may thereby inhibit Th1 cell development.
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PMID:Monocyte chemoattractant protein-1 selectively inhibits the acquisition of CD40 ligand-dependent IL-12-producing capacity of monocyte-derived dendritic cells and modulates Th1 immune response. 1239 Nov 96

In this report we describe pertussis toxin-induced reversible encephalopathy dependent on monocyte chemoattractant protein-1 (MCP-1) overexpression (PREMO), a novel animal model that exhibits features of human encephalopathic complications of inflammatory disorders such as viral meningoencephalitis and Lyme neuroborreliosis as well as the mild toxic encephalopathy that commonly precedes relapses of multiple sclerosis (MS). Overexpression of the mouse MCP-1 gene product (classically termed JE) in astrocytes, the major physiological CNS cellular source of MCP-1, failed to induce neurological impairment. Unexpectedly, transgenic (tg) mice overexpressing MCP-1 at a high level (MCP-1(hi)) manifested transient, severe encephalopathy with high mortality after injections of pertussis toxin (PTx) plus complete Freund's adjuvant (CFA). Surviving mice showed markedly improved function and did not relapse during a prolonged period of observation. Tg mice that expressed lower levels of MCP-1 were affected minimally after CFA/PTx injections, and tg expression of other chemokines failed to elicit this disorder. The disorder was significantly milder in mice lacking T-cells, which therefore play a deleterious role in this encephalopathic process. Disruption of CC chemokine receptor 2 (CCR2) abolished both CNS inflammation and encephalopathy, identifying CCR2 as a relevant receptor for this disorder. Proinflammatory and type 1 cytokines including TNF-alpha, IL-1beta, IFN-gamma, IL-2, RANTES, and IP-10 were elevated in CNS tissues from mice with PREMO. These studies characterize a novel model of reversible inflammatory encephalopathy that is dependent on both genetic and environmental factors.
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PMID:Pertussis toxin-induced reversible encephalopathy dependent on monocyte chemoattractant protein-1 overexpression in mice. 1248 56

The open reading frame (ORF) 74 of gamma-2-herpesviruses encodes a G protein-coupled receptor which is highly conserved in members of this subfamily and is homologous to the CXCR2 chemokine receptor. The viral G protein-coupled receptor has been implicated in viral pathogenesis. However, the advantage of such chemokine receptor homologues to the virus is currently unknown. To address this, we constructed ORF74 deletion mutants of a mouse gamma-2-herpesvirus (MHV-68) and examined the effect of the deletion on viral growth and reactivation from latency. Growth of the mutant viruses in NIH 3T3 cells was similar to that of wild-type virus. However, CXC chemokines with ELR motifs, KC, and macrophage-inflammatory protein 2, significantly increased viral replication of the wild-type, but not the mutant viruses, via a pertussis toxin-insensitive, mitogen-activated protein/extracellular signal-regulated kinase and phosphatidylinositol 3-kinase-dependent pathway. IFN-gamma-inducible protein 10, a CXC chemokine lacking an ELR motif, was able to reverse the effect of KC on viral replication. The mutant viruses also showed significantly reduced reactivation from latently infected mouse splenocytes. Reinsertion of ORF74 into the mutant virus restored the wild-type phenotype. Utilizing a viral CXCR2 homologue to enhance replication and reactivation from latency represents a novel mechanism by which gammaherpesviruses can subvert the immune response.
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PMID:A gammaherpesvirus G protein-coupled receptor homologue is required for increased viral replication in response to chemokines and efficient reactivation from latency. 1249 6

Induction of mucosal immunity in the respiratory tract is crucial for protection against respiratory infections. Here, we have investigated the effects of the routes of immunization as well as of three different adjuvants on the induction of mucosal immune responses. Mice were immunized using intranasal (i.n.) or intraperitoneal (i.p.) routes with the mycobacterium PstS-1 antigen. Cholera toxin (CT), detoxified pertussis toxin (detPT) and RU 41.740 from Klebsiella pneumoniae were compared as mucosal adjuvants. Our data showed that i.n. route of immunization induced the most favorable stimulation of mucosal antigen-specific IgA responses supported by mixed Th cells producing IL-4, IL-5, IFN-gamma. In contrast, i.p. immunizations elicited only enhancement of systemic responses, predominantly of the Th2 type. Furthermore, the use of CT as mucosal adjuvant resulted in the stimulation of a mixed Th cell response whereas detPT evoked mainly Th2 type of responses. Likewise CT, the RU 41.740 adjuvant elicited a mixed Th cell response, albeit supported by much lower numbers of CD4(+) T-cells. Thus, i.n. route of immunization favors the induction of mucosal and systemic immune responses, while the Th cell development at mucosal inductive site is influenced by the adjuvant used for immunizations.
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PMID:B- and T-cell responses to the mycobacterium surface antigen PstS-1 in the respiratory tract and adjacent tissues. Role of adjuvants and routes of immunization. 1253 44

Neonatal immaturity of the immune system is currently believed to generally limit the induction of immune responses to vaccine Ags and to skew them toward type 2 responses. We demonstrated here that Bordetella pertussis infection in very young infants (median, 2 mo old) as well as the first administration of whole-cell pertussis vaccine induces B. pertussis Ag-specific IFN-gamma secretion by the PBMC of these infants. IFN-gamma was secreted by both CD4(+) and CD8(+) T lymphocytes, and the levels of Ag-induced IFN-gamma secretion did not correlate with the age of the infants. Appearance of the specific Th-1 cell-mediated immunity was accompanied by a general shift of the cytokine secretion profile of these infants toward a stronger Th1 profile, as evidenced by the response to a polyclonal stimulation. We conclude that the immune system of 2-mo-old infants is developmentally mature enough to develop Th1 responses in vivo upon infection by B. pertussis or vaccination with whole-cell pertussis vaccines.
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PMID:Bordetella pertussis infection in 2-month-old infants promotes type 1 T cell responses. 1253 14

Dendritic cells (DCs) are the most potent antigen-presenting cells and a prerequisite for the initiation of primary immune response. This study was performed to investigate the contribution of DCs to the initiation of Graves' hyperthyroidism, an organ-specific autoimmune disease in which the thyrotrophin receptor (TSHR) is the major autoantigen. DCs were prepared from bone marrow precursor cells of BALB/c mice by culturing with granulocyte macrophage-colony stimulating factor and interleukin-4. Subcutaneous injections of DCs infected with recombinant adenovirus expressing the TSHR (but not beta-galactosidase) in syngeneic female mice induced Graves'-like hyperthyroidism (8 and 35% of mice after two and three injections, respectively) characterized by stimulating TSHR antibodies, elevated serum thyroxine levels and diffuse hyperplasitc goiter. TSHR antibodies determined by ELISA were of both IgG1 (Th2-type) and IgG2a (Th1-type) subclasses, and splenocytes from immunized mice secreted interferon-gamma (a Th1 cytokine), not interleukin-4 (a Th2 cytokine), in response to TSHR antigen. Surprisingly, IFN-gamma secretion, and induction of antibodies and disease were almost completely suppressed by co-administration of alum/pertussis toxin, a Th2-dominant adjuvant, whereas polyriboinosinic polyribocytidylic acid, a Th1-inducer, enhanced splenocyte secretion of IFN-gamma without changing disease incidence. These observations demonstrate that DCs efficiently present the TSHR to naive T cells to induce TSHR antibodies and Graves'-like hyperthyroidism in mice. In addition, our results challenge the previous concept of Th2 dominance in Graves' hyperthyroidism and provide support for the role of Th1 immune response in disease pathogenesis.
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PMID:Dendritic cells infected with adenovirus expressing the thyrotrophin receptor induce Graves' hyperthyroidism in BALB/c mice. 1256 82

Pertussis toxin (PTX) has been widely used as an adjuvant to induce Th1-mediated organ-specific autoimmune diseases in animal models. However, the cellular and molecular mechanisms remain to be defined. In this study, we showed that dendritic cells (DC) stimulated with PTX (PTX-DC) were able to substitute for PTX to promote experimental autoimmune uveitis (EAU). EAU induced by PTX-DC revealed a typical Th1 response, characterized by high uveitogenic retinal Ag interphotoreceptor retinoid-binding protein (IRBP)-specific IFN-gamma and IL-12 production in the draining lymph nodes, as well as increased levels of anti-IRBP IgG2a and decreased levels of anti-IRBP IgG1 in the serum of IRBP-immunized mice. Furthermore, PTX-DC preferentially induced T cells to produce the Th1 cytokine, IFN-gamma. After being stimulated with PTX, DC exhibited up-regulation of MHC class II, CD80, CD86, CD40, and DEC205. PTX-DC had also increased allostimulatory capacity and IL-12 and TNF-alpha production. Serum IL-12 was increased in naive mice that received PTX-DC i.p. In addition, PTX activated extracellular signal-regulated kinase in DC. Following the inhibition of extracellular signal-regulated kinase signaling, the maturation of PTX-DC was reduced. Subsequently, the ability of PTX-DC to promote IFN-gamma production by T cells in vitro and to induce EAU in vivo was blocked. The results suggest that PTX might exert an adjuvant effect on DC to promote their maturation and the production of proinflammatory cytokines, thereby eliciting a Th1 response.
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PMID:Pertussis toxin enhances Th1 responses by stimulation of dendritic cells. 1257 36


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