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1.
Nucleus (La Habana) ; (65): 32-35, ene.-jun. 2019. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1091386

ABSTRACT

Abstract At INFN-LNL (Istituto Nazionale di Fisica Nucleare- Laboratori Nazionali di Legnaro) SPES (Selective Production of Exotic Species), a new facility for the production of radioactive ion beams is being constructed at INFN-LNL (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Legnaro). Radioactive ion beams of neutron-rich nuclei with high purity, in the range of mass between 80 and 160 amu, will be produced by nuclear reactions induced by 40 MeV protons from a cyclotron. The goal of the ISOLPHARM project is to provide a feasibility study for an innovative technology for the production of extremely very high specific activity beta emitting radionuclides as radiopharmaceutical precursors. The ISOL method, adopted in the ISOLPHARM project (a branch of the SPES project), gives the possibility of obtaining pure isobaric beams. In this way, no isotopic contaminations will be present in the beam and afterwards in a proper trapping substrate. The ground-breaking idea of the ISOLPHARM method was granted an International patent (INFN).


Resumen En INFN-LNL (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Legnaro) SPES (Producción selectiva de especies exóticas), se está construyendo una nueva instalación para la producción de haces de iones radiactivos en INFN-LNL (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Legnaro). Se producirán haces de iones radiactivos de núcleos ricos en neutrones con alta pureza, en el rango de masa entre 80 y 160 amu, por reacciones nucleares inducidas por protones de 40 MeV de un ciclotrón. El objetivo del proyecto ISOLPHARM es proporcionar un estudio de viabilidad para una tecnología innovadora para la producción de radionúclidos emisores de beta de actividad específica extremadamente alta como precursores radiofarmacéuticos. El método ISOL, adoptado en el proyecto ISOLPHARM (una rama del proyecto SPES), ofrece la posibilidad de obtener haces isobáricos puros. De esta manera, no habrá contaminaciones isotópicas en el haz y luego en un sustrato de atrapamiento adecuado. La idea pionera del método ISOLPHARM recibió una patente internacional (INFN).

2.
Nucleus (La Habana) ; (63): 48-52, Jan.-June 2018. graf
Article in English | LILACS | ID: biblio-990209

ABSTRACT

Summary SPES (Selective Production of Exotic Species) is the INFN project for a Nuclear Physics facility for the production of Radioactive Ion Beams (RIBs). It is in advanced construction in Legnaro, with several technological innovations and challenges foreseen, comprehensive of new achievements and improvements. SPES will provide mostly neutron-rich exotic beams, derived by the fission fragments (up to 1013fiss/s) produced in the interaction of an intense proton beam (200 μA) on a direct UCx target. Several other targets will be developed, in order to provide users a large beam selection. The expected SPES beam intensities, their quality and, finally, their maximum energies (up to 11 MeV/n for A=130) will permit to perform forefront research in nuclear structure and nuclear dynamics, studying a region of the nuclear chart far from stability. This goal will be reached by coordinating the developments on the accelerator complex and those of up-to-date experimental set-ups.


Resumen SPES (Selective Production of Exotic Species) es el proyecto INFN para una instalación de física nuclear para la producción de haces de iones radiactivos (RIB). Está en construcción avanzada en Legnaro, que prevé varias innovaciones tecnológicas y desafíos, con nuevos logros y mejoras. SPES proporcionará principalmente haces exóticos ricos en neutrones, derivados de los fragmentos de fisión (hasta 1013fisiones/s) producidos en la interacción de un intenso haz de protones (200 μA) con un blanco UCx directo. Se utilizarán diversos blancos para proporcionar a los usuarios una gran selección de haces. Las intensidades esperadas del haz SPES, su calidad y, finalmente, sus energías máximas (hasta 11 MeV/n para A=130) permitirán realizar investigaciones de vanguardia en la estructura nuclear y la dinámica nuclear, estudiando una región del mapa nuclear lejos de la estabilidad. Este objetivo se alcanzará coordinando los desarrollos en el complejo del acelerador con las configuraciones experimentales actualizadas.

3.
PLoS One ; 7(9): e46041, 2012.
Article in English | MEDLINE | ID: mdl-23029377

ABSTRACT

BACKGROUND: Although currently available IGRA have been reported to be promising markers for TB infection, they cannot distinguish active tuberculosis (TB) from latent infection (LTBI). OBJECTIVE: Children with LTBI, active TB disease or uninfected were prospectively evaluated by an in-house ELISPOT assay in order to investigate possible immunological markers for a differential diagnosis between LTBI and active TB. METHODS: Children at risk for TB infection prospectively enrolled in our infectious disease unit were evaluated by in-house IFN-γ and IL-2 based ELISPOT assays using a panel of Mycobacterium tuberculosis antigens. RESULTS: Twenty-nine children were classified as uninfected, 21 as LTBI and 25 as active TB cases (including 5 definite and 20 probable cases). Significantly higher IFN-γ ELISPOT responses were observed in infected vs. uninfected children for ESAT-6 (p<0.0001), CFP-10 (p<0.0001), TB 10.3 (p = 0.003), and AlaDH (p = 0.001), while differences were not significant considering Ag85B (p = 0.063), PstS1 (p = 0.512), and HspX (16 kDa) (p = 0.139). IL-2 ELISPOT assay responses were different for ESAT-6 (p<0.0001), CFP-10 (p<0.0001), TB 10.3 (p<0.0001), HspX (16 kDa) (p<0.0001), PstS1 (p<0.0001) and AlaDH (p = 0.001); but not for Ag85B (p = 0.063). Comparing results between children with LTBI and those with TB disease differences were significant for IFN-γ ELISPOT only for AlaDH antigen (p = 0.021) and for IL-2 ELISPOT assay for AlaDH (p<0.0001) and TB 10.3 antigen (p = 0.043). ROC analyses demonstrated sensitivity of 100% and specificity of 81% of AlaDH-IL-2 ELISPOT assay in discriminating between latent and active TB using a cut off of 12.5 SCF per million PBMCs. CONCLUSION: Our data suggest that IL-2 based ELISPOT with AlaDH antigen may be of help in discriminating children with active from those with latent TB.


Subject(s)
Antigens, Bacterial/immunology , Enzyme-Linked Immunospot Assay/methods , Interferon-gamma , Interleukin-2 , Latent Tuberculosis/diagnosis , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/diagnosis , Child , Child, Preschool , Humans , Infant , Interferon-gamma/immunology , Interleukin-2/immunology , Latent Tuberculosis/immunology , Prospective Studies , Tuberculosis/immunology
5.
Expert Opin Ther Targets ; 14(7): 759-74, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20536413

ABSTRACT

IMPORTANCE OF THE FIELD: IL-23 is one of the most intriguing cytokine for its many immunological functions, which are the basis of its important role in host defense but also of its possible contribution to the pathogenesis of several diseases. AREAS COVERED IN THIS REVIEW: The literature and patents about IL-23 pathway and their targeting in therapeutic potential applications. Findings published within the last 5 years receive particular attention. WHAT THE READER WILL GAIN: An overview of the emerging role of IL-23 in physiological and pathological conditions and a review of the different approaches (IL-23 pathway-based) currently used for autoimmune diseases and cancer therapies and the results obtained both in preclinical models and in clinical trials. TAKE HOME MESSAGE: Inhibition/targeting of IL-23 may be a good and novel therapeutic strategy, especially in the treatment of diseases like psoriasis, for which current treatments show more pronounced side effects than those of IL-23-blocking and employed as part of specific patient-tailored therapies in inflammatory bowel diseases.


Subject(s)
Autoimmunity/drug effects , Bacterial Infections/drug therapy , Interleukin-23/antagonists & inhibitors , Interleukin-23/physiology , Neoplasms/drug therapy , Animals , Autoimmunity/immunology , Autoimmunity/physiology , Bacterial Infections/immunology , Bacterial Infections/physiopathology , Gene Expression Regulation , Humans , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/physiopathology , Interleukin-17/antagonists & inhibitors , Interleukin-17/genetics , Interleukin-17/physiology , Interleukin-23/chemistry , Interleukin-23/genetics , Neoplasms/immunology , Neoplasms/physiopathology , Psoriasis/drug therapy , Psoriasis/physiopathology , Receptors, Interleukin/chemistry , Receptors, Interleukin/physiology
6.
J Asthma Allergy ; 3: 139-47, 2010 Sep 29.
Article in English | MEDLINE | ID: mdl-21437048

ABSTRACT

Current evidence indicates an inverse association between Helicobacter pylori and asthma and allergy. H. pylori is a Gram-negative bacterium which represents the major cause of peptic ulcer and gastric cancer, and preferentially elicits a T helper (Th)-1 response. Many H. pylori factors, such as the neutrophil-activating factor of H. pylori (HP-NAP), are able to drive Th-1 polarization and to display a powerful inhibition of allergic Th-2 response. This article proposes an overview of the actual knowledge about the effects of H. pylori on asthma and allergy. Special attention has been drawn to HP-NAP as a potential novel strategy for the prevention and treatment of asthma and atopy.

7.
Expert Opin Ther Pat ; 19(5): 623-41, 2009 May.
Article in English | MEDLINE | ID: mdl-19441938

ABSTRACT

BACKGROUND: Cancer remains one of the leading causes of death. Over the past decade, discovery of tumor antigens, as well as new findings in basic immunology, have led to novel opportunities for developing active immunotherapeutical approaches for prevention and treatment of cancer. OBJECTIVE/METHODS: This is a review of the literature and patents on the therapeutic potential of immune-based cell cancer therapies. RESULTS/CONCLUSION: In this article, we discuss the different approaches at present used for immune-based cell cancer therapies, and the results obtained both in preclinical models and in clinical trials of hematological malignancies and solid tumors.


Subject(s)
Cancer Vaccines/therapeutic use , Immunotherapy/methods , Neoplasms/therapy , Animals , Antigens, Neoplasm/immunology , Cancer Vaccines/pharmacology , Clinical Trials as Topic , Drug Evaluation, Preclinical , Humans , Immunity, Innate/immunology , Neoplasms/immunology , Neoplasms/prevention & control , Patents as Topic
8.
Cancer Immunol Immunother ; 58(11): 1819-30, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19319530

ABSTRACT

Gastric cancer is a significant cause of morbidity and mortality worldwide. Surgical resection remains the primary curative treatment for gastric adenocarcinoma, but the poor (15-35%) survival rate at 5 years has prompted many studies for new therapeutic strategies, such as specific immunotherapy. The aim of this study was to analyze the functional properties of the T cell response to different antigen peptides related to gastric cancer in patients with gastric adenocarcinoma. To this purpose, we have cloned and characterized tumor-infiltrating T cells (TILs) isolated from the neoplastic gastric tissue samples. A T cell response specific to different peptides of gastric cancer antigens tested was documented in 17 out of 20 patients, selected for their HLA-A02 and/or -A24 alleles. Most of the cancer peptide-specific TILs expressed a Th1/Tc1 profile and cytotoxic activity against target cells. The effector functions of cancer peptide-specific T cells obtained from the peripheral blood of the same patients were also studied. The majority of peripheral blood peptide-specific T cells also expressed the Th1/Tc1 functional profile. In conclusion, in most of the patients with gastric adenocarcinoma, a specific type-1 T cell response to gastric cancer antigens was detectable and would have the potential of hamper tumor cell growth. However, in order to get tumor cell killing in vivo, the activity and the number of cancer peptide-specific Th1/Tc1 cells probably need to be enhanced by vaccination with the appropriate cancer antigenic peptides or by injection of the autologus tumor peptide-specific T cells expanded in vitro.


Subject(s)
Adenocarcinoma/immunology , Antigens, Neoplasm/immunology , Peptide Fragments/immunology , Stomach Neoplasms/immunology , T-Lymphocytes/immunology , Aged , Apoptosis , Cytotoxicity, Immunologic , Female , Flow Cytometry , Herpesvirus 4, Human/genetics , Humans , Lymphocytes, Tumor-Infiltrating/immunology , Male , Middle Aged , Receptors, Antigen, T-Cell, alpha-beta/immunology
9.
FEMS Immunol Med Microbiol ; 56(1): 1-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19220467

ABSTRACT

Bronchial asthma and allergic diseases are orchestrated by T-cells producing T-helper type 2 (Th2) cytokines, such as interleukin-4 (IL-4) and IL-5, and are inhibited by Th1 responses. Helicobacter pylori has chronically infected the human population for c. 100,000 years and preferentially elicits a Th1 mucosal immune response with the production of interferon-gamma and IL-12. Among several bacterial factors, the neutrophil-activating protein of H. pylori (HP-NAP) not only plays a key role in driving Th1 inflammation but it is also able to inhibit Th2 responses in vitro and in vivo in allergic bronchial asthma, in humans and mice. Both systemic and mucosal administrations of HP-NAP are successful in reducing eosinophilia, immunoglobulin E and systemic Th2 cytokines at the bronchial level. Thus, these results identify HP-NAP as a candidate for novel strategies for the prevention and treatment of allergic diseases.


Subject(s)
Asthma/immunology , Helicobacter Infections/immunology , Helicobacter pylori , Hypersensitivity/immunology , Animals , Asthma/complications , Asthma/metabolism , Asthma/physiopathology , Bacterial Proteins/biosynthesis , Bacterial Proteins/immunology , Cytokines/biosynthesis , Cytokines/immunology , Helicobacter Infections/complications , Helicobacter Infections/metabolism , Helicobacter pylori/immunology , Helicobacter pylori/metabolism , Humans , Hypersensitivity/complications , Hypersensitivity/metabolism , Inflammation/immunology , Inflammation/metabolism , Mice , Neutrophil Activation , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/metabolism
10.
Arthritis Rheum ; 58(11): 3609-17, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18975343

ABSTRACT

OBJECTIVE: Human Lyme arthritis caused by Borrelia burgdorferi is characterized by an inflammatory infiltrate that consists mainly of neutrophils and T cells. This study was undertaken to evaluate the role of the innate and acquired immune responses elicited by the neutrophil-activating protein A (NapA) of B burgdorferi in patients with Lyme arthritis. METHODS: Serum anti-NapA antibodies were measured in 27 patients with Lyme arthritis and 30 healthy control subjects. The cytokine profile of synovial fluid T cells specific for NapA was investigated in 5 patients with Lyme arthritis. The cytokine profile induced by NapA in neutrophils and monocytes was also investigated. RESULTS: Serum anti-NapA antibodies were found in 48% of the patients with Lyme arthritis but were undetectable in the healthy controls. T cells from the synovial fluid of patients with Lyme arthritis produced interleukin-17 (IL-17) in response to NapA. Moreover, NapA was able to induce the expression of IL-23 in neutrophils and monocytes, as well as the expression of IL-6, IL-1beta, and transforming growth factor beta (TGFbeta) in monocytes, via Toll-like receptor 2. CONCLUSION: These findings indicate that NapA of B burgdorferi is able to drive the expression of IL-6, IL-1beta, IL-23, and TGFbeta by cells of the innate immune system and to elicit a synovial fluid Th17 cell response that might play a crucial role in the pathogenesis of Lyme arthritis.


Subject(s)
Bacterial Proteins/immunology , Borrelia burgdorferi/immunology , Chemokines, CXC/immunology , Interleukin-17/immunology , Lyme Disease/immunology , T-Lymphocytes/immunology , Adolescent , Adult , Antibodies, Bacterial/analysis , Child , Female , Humans , Interleukin-17/biosynthesis , Interleukin-1beta/biosynthesis , Interleukin-23/biosynthesis , Interleukin-6/biosynthesis , Male , Middle Aged , Monocytes/immunology , Neutrophils/immunology , Synovial Fluid/immunology , Transforming Growth Factor beta/biosynthesis
11.
J Allergy Clin Immunol ; 122(5): 908-913.e5, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18804852

ABSTRACT

BACKGROUND: The Helicobacter pylori neutrophil-activating protein (HP-NAP) is able to induce IL-12 expression by cells of innate immunity and to shift to T(H)1 human allergen-specific T(H)2 cells in vitro. OBJECTIVE: We performed an in vivo investigation of the ability of HP-NAP to downmodulate the T(H)2 response induced in mice by Trichinella spiralis infection. METHODS: Groups of T spiralis-infected BALB/c mice received intraperitoneal PBS/rat IgG2b (control animals) or 10 microg of HP-NAP with or without anti-Toll-like receptor 2 antibody on days 10 and 28 after infection. Blood eosinophils, total and T spiralis-specific IgE levels, and cytokine levels were measured in the plasma up to day 42, when splenocytes were cultured for cytokine production. RESULTS: Although control animals showed significant eosinophilia and increase of total and T spiralis-specific IgE, IL-4, and IL-5 levels from days 10 to 14, HP-NAP-treated animals showed less eosinophilia and total and excretory/secretory antigens of T spiralis-specific IgE in the blood. HP-NAP-treated animals also had higher IL-12 and IFN-gamma plasma levels and lower IL-4 and IL-5 levels. The addition of anti-Toll-like receptor 2 antibody abrogated the anti-T(H)2/pro-T(H)1 activity of HP-NAP. CONCLUSION: This study provides evidence that HP-NAP enhances endogenous IL-12 and IFN-gamma response and exerts a powerful anti-T(H)2 activity in vivo, targeting both IL-5-induced eosinophilia and IL-4-mediated hyper-IgE responses induced by parasitic infection.


Subject(s)
Bacterial Proteins/immunology , Th2 Cells/immunology , Trichinella spiralis , Trichinellosis/immunology , Animals , Antigens, Bacterial/immunology , Disease Models, Animal , Down-Regulation , Eosinophilia/immunology , Female , Immunoglobulin E/immunology , Interferon-gamma/immunology , Interleukin-12/immunology , Interleukin-4/immunology , Interleukin-5/immunology , Mice , Mice, Inbred BALB C , Th1 Cells/immunology
12.
Cell Microbiol ; 10(11): 2355-63, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18671823

ABSTRACT

The Helicobacter pylori neutrophil-activating protein (HP-NAP) is able in vitro to elicit IL-12 and IL-23 production via agonistic interaction with toll-like receptor 2, and to promote Th1 polarization of allergen-specific T-cell responses. This study was aimed to assess whether systemic/intraperitoneal and/or mucosal HP-NAP administration inhibited the Th2-mediated bronchial inflammation using a mouse model of allergic asthma induced by inhaled ovalbumin (OVA). Systemic HP-NAP delivery markedly reduced the lung eosinophilia in response to repeated challenge with aerosolized OVA. Likewise, the production of IL-4, IL-5 and GM-CSF was significantly lower in the bronchoalveolar lavage of animals treated with systemic HP-NAP plus OVA than that of animals treated with OVA alone. Systemic HP-NAP also significantly resulted in both reduction of total serum IgE and increase of IL-12 plasma levels. Mucosal administration of HP-NAP was equally successful as the systemic delivery in reducing eosinophilia, IgE and Th2 cytokine levels in bronchoalveolar lavage. However, no suppression of lung eosinophilia and bronchial Th2 cytokines was observed in toll-like receptor 2-knock-out mice following HP-NAP treatment. These results identify HP-NAP as a candidate for novel strategies of prevention and treatment of allergic diseases.


Subject(s)
Asthma/immunology , Bacterial Proteins/immunology , Inflammation/immunology , Neutrophils/immunology , Th2 Cells/immunology , Animals , Antigens, Bacterial/genetics , Antigens, Bacterial/immunology , Bacterial Proteins/genetics , Bronchoalveolar Lavage Fluid/cytology , Cytokines/blood , Cytokines/immunology , Humans , Immunoglobulin E/blood , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Ovalbumin/immunology , Pulmonary Eosinophilia/immunology
13.
PLoS Negl Trop Dis ; 2(6): e255, 2008 Jun 25.
Article in English | MEDLINE | ID: mdl-18575596

ABSTRACT

Infectious diseases remain a major health and socioeconomic problem in many low-income countries, particularly in sub-Saharan Africa. For many years, the three most devastating diseases, HIV/AIDS, malaria, and tuberculosis (TB) have received most of the world's attention. However, in rural and impoverished urban areas, a number of infectious diseases remain neglected and cause massive suffering. It has been calculated that a group of 13 neglected infectious diseases affects over one billion people, corresponding to a sixth of the world's population. These diseases include infections with different types of worms and parasites, cholera, and sleeping sickness, and can cause significant mortality and severe disabilities in low-income countries. For most of these diseases, vaccines are either not available, poorly effective, or too expensive. Moreover, these neglected diseases often occur in individuals who are also affected by HIV/AIDS, malaria, or TB, making the problem even more serious and indicating that co-infections are the rule rather than the exception in many geographical areas. To address the importance of combating co-infections, scientists from 14 different countries in Africa and Europe met in Addis Ababa, Ethiopia, on September 9-11, 2007. The message coming from these scientists is that the only possibility for winning the fight against infections in low-income countries is by studying, in the most global way possible, the complex interaction between different infections and conditions of malnourishment. The new scientific and technical tools of the post-genomic era can allow us to reach this goal. However, a concomitant effort in improving education and social conditions will be needed to make the scientific findings effective.


Subject(s)
Acquired Immunodeficiency Syndrome , Communicable Diseases , European Union , Malaria , Research/standards , Tuberculosis , Acquired Immunodeficiency Syndrome/complications , Acquired Immunodeficiency Syndrome/immunology , Animals , Communicable Diseases/complications , Communicable Diseases/immunology , HIV Infections/complications , HIV Infections/immunology , Humans , Malaria/complications , Malaria/immunology , Tuberculosis/complications , Tuberculosis/immunology
14.
FEMS Immunol Med Microbiol ; 50(2): 157-64, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17521355

ABSTRACT

During evolution microorganisms have developed several immune modulating strategies. The Helicobacter pylori neutrophil-activating protein (HP-NAP) is a virulence factor that attracts and activates neutrophils, and promotes their endothelial adhesion and the production of oxygen radicals and chemokines, including CXCL8, CCL3 and CCL4. HP-NAP, a TLR2 agonist, is an immune modulator able to induce the expression of interleukin-12 (IL-12) and IL-23 by human neutrophils and monocytes. In fact, HP-NAP has the potential to shift antigen-specific T-cell responses from a predominant Th2 to a polarized Th1 cytotoxic phenotype, characterized by high levels of interferon-gamma and tumor necrosis factor-alpha production. Thus, HP-NAP is a key factor driving Th1 inflammation in H. pylori infection and may be a new tool for future therapeutic strategies aimed at redirecting Th2 into Th1 responses, for example in atopy, vaccinology and cancer immunotherapy.


Subject(s)
Bacterial Proteins/immunology , Helicobacter Infections/immunology , Helicobacter pylori/immunology , Neutrophils/immunology , Virulence Factors/immunology , Cytokines/immunology , Humans , Monocytes/immunology , Monocytes/microbiology , Neutrophils/microbiology
15.
J Clin Invest ; 116(4): 1092-101, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16543949

ABSTRACT

The Helicobacter pylori neutrophil-activating protein (HP-NAP) is a virulence factor of H. pylori that stimulates in neutrophils high production of oxygen radicals and adhesion to endothelial cells. We report here that HP-NAP is a TLR2 agonist able to induce the expression of IL-12 and IL-23 by neutrophils and monocytes. Addition in culture of HP-NAP, as an immune modulator, to antigen-induced T cell lines resulted in a remarkable increase in the number of IFN-gamma-producing T cells and decrease of IL-4-secreting cells, thus shifting the cytokine profile of antigen-activated human T cells from Th2 to a Th1 cytotoxic phenotype. We also found that in vivo HP-NAP elicited an antigen-specific Th1-polarized T cell response in the gastric mucosa of H. pylori-infected patients. These data indicate HP-NAP as an important factor of H. pylori able to elicit cells of the innate immune system to produce IL-12 and IL-23, and they suggest it as a new tool for promoting Th1 immune responses.


Subject(s)
Bacterial Proteins/metabolism , Helicobacter pylori/metabolism , Th1 Cells/immunology , Adult , Allergens/metabolism , Allergens/pharmacology , Bacterial Proteins/pharmacology , CD4 Antigens/metabolism , Cells, Cultured , Dendritic Cells/metabolism , Female , Genes, MHC Class II , Granulocytes/metabolism , Humans , Immunity, Innate , Interferon-gamma/metabolism , Interleukin-12/biosynthesis , Interleukin-23 , Interleukin-23 Subunit p19 , Interleukins/biosynthesis , Male , Middle Aged , Monocytes/metabolism , Neutrophils/metabolism , Phenotype , Th1 Cells/metabolism , Time Factors , Toll-Like Receptor 2/agonists , Toll-Like Receptor 2/metabolism , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation
16.
Nat Rev Microbiol ; 4(2): 151-9, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16415930

ABSTRACT

Helicobacter pylori can be regarded as a model pathogen for studying persistent colonization of humans. Phase-variable expression of Lewis blood-group antigens by H. pylori allows this microorganism to modulate the host T-helper-1-cell versus T-helper-2-cell response. We describe a model in which interactions between host lectins and pathogen carbohydrates facilitate asymptomatic persistence of H. pylori. This delicate balance, favourable for both the pathogen and the host, could lead to gastric autoimmunity in genetically susceptible individuals.


Subject(s)
Helicobacter Infections/immunology , Helicobacter Infections/microbiology , Helicobacter pylori/immunology , Stomach Diseases/immunology , Stomach Diseases/microbiology , Amino Acid Sequence , Autoimmunity , Genetic Predisposition to Disease , Helicobacter Infections/genetics , Humans , Molecular Sequence Data , Stomach Diseases/genetics
17.
J Immunol ; 174(10): 6509-17, 2005 May 15.
Article in English | MEDLINE | ID: mdl-15879154

ABSTRACT

Epidemiological studies suggest the potential importance of an inflammatory component in atherosclerosis and support the hypothesis that immune responses to Ags of pathogens cross-react with homologous host proteins due to molecular mimicry. Protein candidates involved may be the stress-induced proteins known as heat shock proteins (HSP). In this study, we report that atherosclerotic plaques harbor in vivo-activated CD4(+) T cells that recognize the human 60-kDa HSP. Such in vivo-activated 60-kDa HSP-specific T cells are not detectable in the peripheral blood. In patients with positive serology and PCR for Chlamydia pneumoniae DNA, but not in patients negative for both, most of plaque-derived T cells specific for human 60-kDa HSP also recognized the C. pneumoniae 60-kDa HSP. We characterized the submolecular specificity of such 60-kDa HSP-specific plaque-derived T cells and identified both the self- and cross-reactive epitopes of that autoantigen. On challenge with human 60-kDa HSP, most of the plaque-derived T cells expressed Th type 1 functions, including cytotoxicity and help for monocyte tissue factor production. We suggest that arterial endothelial cells, undergoing classical atherosclerosis risk factors and conditioned by Th type 1 cytokines, express self 60-kDa HSP, which becomes target for both autoreactive T cells and cross-reactive T cells to microbial 60-kDa HSP via a mechanism of molecular mimicry. This hypothesis is in agreement with the notion that immunization with HSP exacerbates atherosclerosis, whereas immunosuppression and T cell depletion prevent the formation of arteriosclerotic lesions in experimental animals.


Subject(s)
Arteriosclerosis/immunology , Arteriosclerosis/pathology , Autoantigens/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , Chaperonin 60/immunology , Aged , Amino Acid Sequence , Antigen Presentation/immunology , Arteriosclerosis/microbiology , Autoantigens/metabolism , CD4-Positive T-Lymphocytes/microbiology , Cell Movement/immunology , Chaperonin 60/metabolism , Chlamydophila pneumoniae/immunology , Clone Cells , Cytokines/biosynthesis , Epitopes, T-Lymphocyte/immunology , Female , Humans , Jurkat Cells , Lymphocyte Activation/immunology , Male , Middle Aged , Molecular Mimicry/immunology , Molecular Sequence Data , Monocytes/immunology , Monocytes/metabolism , Thromboplastin/biosynthesis
18.
FEMS Immunol Med Microbiol ; 44(2): 113-9, 2005 May 01.
Article in English | MEDLINE | ID: mdl-15866204

ABSTRACT

Helicobacter pylori infection is the major cause of gastroduodenal pathologies, but only a minority of infected patients develop chronic and life threatening diseases, as peptic ulcer, gastric cancer, B-cell lymphoma, or autoimmune gastritis. The type of host immune response against H. pylori is crucial for the outcome of the infection. A predominant H. pylori-specific Th1 response, characterized by high IFN-gamma, TNF-alpha, and IL-12 production associates with peptic ulcer, whereas combined secretion of both Th1 and Th2 cytokines are present in uncomplicated gastritis. Gastric T cells from MALT lymphoma exhibit abnormal help for autologous B-cell proliferation and reduced perforin- and Fas-Fas ligand-mediated killing of B cells. In H. pylori-infected patients with autoimmune gastritis cytolytic T cells infiltrating the gastric mucosa cross-recognize different epitopes of H. pylori proteins and H+K+ ATPase autoantigen. These data suggest that peptic ulcer can be regarded as a Th1-driven immunopathological response to some H. pylori antigens, whereas deregulated and exhaustive H. pylori-induced T cell-dependent B-cell activation can support the onset of low-grade B-cell lymphoma. Alternatively, H. pylori infection may lead in some individuals to gastric autoimmunity via molecular mimicry.


Subject(s)
Cytokines/metabolism , Helicobacter Infections/immunology , Helicobacter Infections/physiopathology , Helicobacter pylori/immunology , Autoimmune Diseases/immunology , Autoimmune Diseases/microbiology , Helicobacter Infections/microbiology , Humans , Lymphoma, B-Cell, Marginal Zone/immunology , Lymphoma, B-Cell, Marginal Zone/microbiology , Peptic Ulcer/immunology , Peptic Ulcer/microbiology , Stomach Neoplasms/immunology , Stomach Neoplasms/microbiology , T-Lymphocytes/immunology
19.
Blood ; 106(2): 626-34, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15817684

ABSTRACT

Common variable immunodeficiency (CVID) is a primary immune disorder characterized by impaired antibody production, which is in many instances secondary to defective T-cell function (T-CVID). We have previously identified a subset of patients with T-CVID characterized by defective T-cell receptor (TCR)-dependent protein tyrosine phosphorylation. In these patients, ZAP-70 fails to be recruited to the TCR as the result of impaired CD3zeta phosphorylation, which is, however, not dependent on defective Lck expression or activity. Here we show that neither Fyn nor CD45 is affected in these patients. On the other hand, T-CVID T cells show dramatic defects in the Vav/Rac pathway controlling F-actin dynamics. A significant deficiency in Vav protein was indeed observed; in 3 of 4 patients with T-CVID, it was associated with reduced VAV1 mRNA levels. The impairment in Vav expression correlated with defective F-actin reorganization in response to TCR/CD28 co-engagement. Furthermore, TCR/CD28-dependent up-regulation of lipid rafts at the cell surface, which requires F-actin dynamics, was impaired in these patients. The actin cytoskeleton defect could be reversed by reconstitution of Vav1 expression in the patients' T cells. Results demonstrate an essential role of Vav in human T cells and strongly suggest Vav insufficiency in T-CVID.


Subject(s)
Actins/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Common Variable Immunodeficiency/genetics , Common Variable Immunodeficiency/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , CD3 Complex/metabolism , Calcium Signaling , Common Variable Immunodeficiency/immunology , DNA, Complementary/genetics , G(M1) Ganglioside/metabolism , Gene Expression , Humans , In Vitro Techniques , Leukocyte Common Antigens/genetics , Membrane Microdomains/metabolism , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins c-fyn , Proto-Oncogene Proteins c-vav , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Antigen, T-Cell/metabolism , ZAP-70 Protein-Tyrosine Kinase , src-Family Kinases/genetics
20.
Int Rev Immunol ; 24(1-2): 63-91, 2005.
Article in English | MEDLINE | ID: mdl-15763990

ABSTRACT

The gastric mucosal pathogen Helicobacter pylori induces autoantibodies directed against the gastric proton pump H+,K+-ATPase in 20-30% of infected patients. The presence of these autoantibodies is associated with severity of gastritis, increased atrophy, and apoptosis in the corpus mucosa, and patients with these autoantibodies infected with H. pylori display histopathological and clinical features that are similar to those of autoimmune gastritis (AIG). This review will focus on the T helper cell responses, cytokines, and adhesion molecules involved in corpus mucosal atrophy in chronic H. pylori gastritis and in AIG, and the role of H. pylori in the onset of AIG.


Subject(s)
Autoimmune Diseases/etiology , Gastritis/etiology , Helicobacter Infections/immunology , Helicobacter pylori , Anemia, Pernicious/complications , Autoimmune Diseases/immunology , Autoimmune Diseases/microbiology , Cytokines/metabolism , Gastritis/immunology , Gastritis/microbiology , Gastritis, Atrophic/etiology , Humans , Parietal Cells, Gastric/pathology , T-Lymphocytes/immunology
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