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1.
Ned Tijdschr Tandheelkd ; 127(6): 358-364, 2020 Jun.
Artigo em Holandês | MEDLINE | ID: mdl-32716399

RESUMO

Gingivitis and periodontitis can worsen with reduced immune fitness. Various causes can reduce immune fitness in a host, as a result of which the balance between the host and the microbiome is disturbed. Among others, lifestyle factors, such as stress and smoking, can have a negative influence on immune fitness. An association has been demonstrated between stress and periodontitis and also acute necrotising ulcerative gingivitis or periodontitis. There are indications that neurons are able to secrete pro-inflammatory cytokines and chemokines that worsen chronic inflammatory reactions in the periodontium and compromise immune fitness. In vitro studies show high cortisol levels may contribute to the increased growth of P. gingivalis. Stress as a risk factor for periodontitis and the role of stress as a negative influence on the results of periodontal treatment are difficult to estimate clinically. Nevertheless, attention to and awareness of stress as an aspect of the comprehensive set of risk factors for periodontitis can diminish its negative impact on immune fitness.


Assuntos
Gengivite , Periodontite , Humanos , Inflamação , Periodonto
2.
Pol J Vet Sci ; 19(2): 309-15, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27487504

RESUMO

Microbiological and parasitological investigation was carried out on a colony of feral pigeons, located in a green area near the main hospital of a Central Italy city. One hundred pigeons were submitted to clinical examination. Cloacal swabs, grouped in pool of 4 samples, were analyzed to detect the presence of Coxiella burnetii, Chlamydia psittaci, Chlamydophila spp. using a biomolecular procedure, while individual cloacal samples were examined for Salmonella spp., Campylobacter spp., and yeasts by means of a specific culture media. An ELISA test was used to determine the presence of Giardia spp., and Cryptosporidium spp. coproantigens. Individual serological samples were also tested with the modified agglutination test (MAT) in order to detect antibodies against Toxoplasma gondii. The pigeons did not show any clinical signs. The cloacal pools proved to be negative for C. burnetii DNA while three pools were positive for C. psittaci or Chlamydophila spp. DNAs. Salmonella spp. was not detected. C. jejuni and C. coli were found in 13% and 4% of the samples, respectively. No Giardia spp. and Cryptosporidium spp. were detected. Thirty-three out of 100 samples (33%) were positive for yeast colonies. The seroprevalence for T. gondii was 8%. Although with moderate incidence, potentially zoonotic agents were present thus highlighting the need for sanitary surveillance on feral pigeon colonies.


Assuntos
Infecções Bacterianas/veterinária , Doenças das Aves/microbiologia , Columbidae , Infecções Protozoárias em Animais/parasitologia , Animais , Antígenos de Protozoários/isolamento & purificação , Infecções Bacterianas/epidemiologia , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Cloaca/microbiologia , Cloaca/parasitologia , DNA Bacteriano/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Itália/epidemiologia , Infecções Protozoárias em Animais/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Zoonoses
3.
Infection ; 42(1): 141-51, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24150958

RESUMO

PURPOSE: We compared the risk factors, the diagnostic tools and the outcome of filamentous fungal infections (FFIs) in hematological patients (HAEs) and non-hematological patients (non-HAEs). METHODS: Prospective surveillance (2009-2011) of proven and probable FFIs was implemented in 23 Italian hospitals. RESULTS: Out of 232 FFIs, 113 occurred in HAEs and 119 in non-HAEs. The most frequent infection was invasive aspergillosis (76.1 % for HAEs, 56.3 % for non-HAEs), and the localization was principally pulmonary (83.2 % for HAEs, 74.8 % for non-HAEs). Neutropenia was a risk factor for 89.4 % HAEs; the main underlying condition was corticosteroid treatment (52.9 %) for non-HAEs. The distribution of proven and probable FFIs was different in the two groups: proven FFIs occurred more frequently in non-HAEs, whereas probable FFIs were correlated with the HAEs. The sensitivity of the galactomannan assay was higher for HAEs than for non-HAEs (95.3 vs. 48.1 %). The overall mortality rate was 44.2 % among the HAEs and 35.3 % among the non-HAEs. The etiology influenced the patient outcomes: mucormycosis was associated with a high mortality rate (57.1 % for HAEs, 77.8 % for non-HAEs). CONCLUSIONS: The epidemiological and clinical data for FFIs were not identical in the HAEs and non-HAEs. The differences should be considered to improve the management of FFIs according to the patients' setting.


Assuntos
Fungos/classificação , Fungos/isolamento & purificação , Micoses/epidemiologia , Micoses/microbiologia , Sistema de Registros , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes Diagnósticos de Rotina , Feminino , Neoplasias Hematológicas/complicações , Hospitais , Humanos , Itália/epidemiologia , Masculino , Técnicas Microbiológicas/métodos , Pessoa de Meia-Idade , Micoses/diagnóstico , Micoses/mortalidade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
4.
Anal Bioanal Chem ; 405(19): 6365-71, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23722889

RESUMO

We report the development of an indirect ELISA procedure for specific identification of chicken-egg yolk and animal glues in painting micro-samples. The results presented integrate previously published work on ELISA recognition of bovine ß-casein and chicken ovalbumin in painting materials. The integrated final ELISA procedure-optimised for protein extraction, immuno-reagent concentrations, blocking solution, incubation time, and temperature-enables multiplex identification, in single samples, of proteinaceous materials, i.e. chicken-egg yolk and albumen, animal glues, and bovine milk and/or casein, mainly used by painters in the past. The procedure has been systematically tested on laboratory models of mural and easel paintings, both naturally and artificially aged, to assess possible inhibitory effects on the immuno-reaction caused by inorganic painting materials (pigments and substrates) and by protein degradation resulting from aging processes. Real samples from case studies, which had previously been investigated and characterised by spectroscopy and chromatography, were successfully studied by use of the developed ELISA procedure. The commercial availability of all the immuno-reagents used, the affordable analytical equipment, and the specificity, sensitivity, and rapidity of ELISA make this method very attractive to diagnostic laboratories in the field of cultural heritage science. Possible further developments to the analytical potential of this technique include improvement of antibody performance and inclusion of other classes of bio-molecules as analytical targets.


Assuntos
Adesivos/análise , Corantes/análise , Ensaio de Imunoadsorção Enzimática/métodos , Pintura/análise , Animais , Caseínas/análise , Bovinos , Galinhas , Gema de Ovo/química , Ovalbumina/análise , Pinturas
5.
Genes Immun ; 13(2): 197-201, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21866115

RESUMO

Non-Hodgkin lymphoma (NHL) has been associated with immunological defects, chronic inflammatory and autoimmune conditions. Given the link between immune dysfunction and NHL, genetic variants in toll-like receptors (TLRs) have been regarded as potential predictive factors of susceptibility to NHL. Adequate anti-tumoral responses are known to depend on TLR9 function, such that the use of its synthetic ligand is being targeted as a therapeutic strategy. We investigated the association between the functional rs5743836 polymorphism in the TLR9 promoter and risk for B-cell NHL and its major subtypes in three independent case-control association studies from Portugal (1160 controls, 797 patients), Italy (468 controls, 494 patients) and the US (972 controls, 868 patients). We found that the rs5743836 polymorphism was significantly overtransmitted in both Portuguese (odds ratio (OR), 1.85; P=7.3E-9) and Italian (OR, 1.84; P=6.0E-5) and not in the US cohort of NHL patients. Moreover, the increased transcriptional activity of TLR9 in mononuclear cells from patients harboring rs5743836 further supports a functional effect of this polymorphism on NHL susceptibility in a population-dependent manner.


Assuntos
Linfoma não Hodgkin/genética , Polimorfismo Genético , Receptor Toll-Like 9/genética , Feminino , Genética Populacional , Humanos , Linfoma não Hodgkin/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
6.
Anal Bioanal Chem ; 399(9): 3011-23, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21170522

RESUMO

Enzyme-linked immunosorbent assay (ELISA) analysis of proteins offers a particularly promising approach for investigations in cultural heritage on account of its appreciated properties of being highly specific, sensitive, relatively fast, and cost-affordable with respect to other conventional techniques. In spite of that, it has never been fully exploited for routine analyses of painting materials in consideration of several analytical issues that inhibited its diffusion in conservation science: limited sample dimensions, decrease of binder solubility and reduced availability of antibody bonding sites occurring with protein degradation. In this study, an ELISA analytical protocol suited for the identification of aged denatured proteins in ancient painting micro-samples has been developed. We focused on the detection of bovine ß-casein and chicken ovalbumin as markers of bovine milk (or casein) and chicken albumen, respectively. A systematic experimentation of the ELISA protocol has been carried out on mock-ups of mural and easel painting prepared with 13 different pigments to assess limits and strengths of the method when applied for the identification of proteins in presence of a predominant inorganic matrix. The analytical procedure has been optimized with respect to protein extraction, antibodies' concentrations, incubation time and temperature; it allows the detection of the investigated proteins with sensitivity down to nanograms. The optimized protocol was then tested on artificially aged painting models. Analytical results were very encouraging and demonstrated that ELISA allows for protein analysis also in degraded painting samples. To address the feasibility of the developed ELISA methodology, we positively investigated real painting samples and results have been cross-validated by gas chromatography-mass spectrometry.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Pintura/análise , Pinturas , Proteínas/análise , Animais , Caseínas/análise , Bovinos , Galinhas , Clara de Ovo/análise
7.
J Glob Antimicrob Resist ; 22: 231-237, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32061880

RESUMO

OBJECTIVES: This study was conducted to assess the prevalence of azole resistance in Aspergillus isolates from patients with haematological malignancies or who were undergoing haematopoietic stem cell transplantation and to identify the molecular mechanism of resistance. METHODS: In this 28-month prospective study involving 18 Italian centres, Aspergillus isolates from surveillance cultures were collected and screened for azole resistance, and mutations in the cyp51A gene were identified. Resistant isolates were genotyped by microsatellite analysis, and the allelic profiles were compared with those of resistant environmental and clinical isolates from the same geographical area that had been previously genotyped. RESULTS: There were 292 Aspergillus isolates collected from 228 patients. The isolates belonged mainly to the section Fumigati (45.9%), Nigri (20.9%), Flavi (16.8%) and Terrei (4.8%). Three isolates showed itraconazole resistance: Aspergillus fumigatus sensu stricto, Aspergillus lentulus (section Fumigati) and Aspergillus awamori (section Nigri). The itraconazole resistance rates were 1% and 1.48% considering all Aspergillus spp. isolates and the Aspergillus section Fumigati, respectively. The prevalence of azole resistance among all the patients was 1.3%. Among patients harbouring A. fumigatus sensu stricto isolates, the resistance rate was 0.79%. The A. fumigatus isolate, with the TR34/L98H mutation, was genotypically distant from the environmental and clinical strains previously genotyped. CONCLUSIONS: In this study, the Aspergillus azole resistance rate was 1% (3/292). In addition to A. fumigatus sensu stricto, A. lentulus and A. awamori azole-resistant isolates were identified. Therefore, it is important have a correct identification at the species level to address a rapid therapy better, quickly understand the shift towards cryptic species and have an updated knowledge of the local epidemiology.


Assuntos
Azóis , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus/genética , Azóis/farmacologia , Humanos , Itália/epidemiologia , Testes de Sensibilidade Microbiana , Estudos Prospectivos
8.
Anal Bioanal Chem ; 392(1-2): 57-64, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18392811

RESUMO

Immunofluorescence microscopy offers a highly specific analytical tool for unambiguous recognition and mapping of proteins in complex matrices. In the present work, the analytical potentials of immunofluorescence microscopy have been exploited to provide recognition of proteinaceous binders in painting cross-sections. An optimised analytical protocol is proposed for the identification of ovalbumin and of bovine serum albumin as markers of egg white and casein, respectively. The study has been carried out on laboratory model samples simulating both easel and mural paintings. The obtained results demonstrated the effectiveness of the method, suggesting the potential future use of immunofluorescence microscopy as a routine diagnostic tool in conservation science. Possible developments of the proposed methodology in order to improve the specificity of the method and its detection sensitivity are presented and discussed.


Assuntos
Caseínas/análise , Proteínas do Ovo/análise , Microscopia de Fluorescência/métodos , Ovalbumina/análise , Pinturas , Soroalbumina Bovina/análise , Reações Antígeno-Anticorpo , Corantes/análise , Clara de Ovo/análise , Clara de Ovo/química , Sensibilidade e Especificidade
9.
G Ital Med Lav Ergon ; 28(4): 466-71, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-17380948

RESUMO

The purpose of this study was to quantify and identify the airborne microbial contamination in Umbria Sawmills. In this paper we reported the preliminary results of our analysis. Microbial contaminants (fungi and bacteria) were assessed with passive (IMA Standard) and active (SAS microbial sampler) methods. There were significant differences of bacterial and/or fungal CFU/m3 values between the outdoor and indoor environments during the normal sawmills activity. Staphylococcus, Sphingomonas, Pasteurella, were the most predominant bacteria. The most predominant isolated fungi belong to Cladosporium, Penicillium, Alternaria and Aspergillus genus.


Assuntos
Microbiologia do Ar , Poluentes Ocupacionais do Ar , Poluição do Ar em Ambientes Fechados/análise , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Exposição Ocupacional/análise , Madeira , Poluentes Ocupacionais do Ar/isolamento & purificação , Aspergillus/isolamento & purificação , Cladosporium/isolamento & purificação , Contagem de Colônia Microbiana , Poeira , Humanos , Itália , Pasteurella/isolamento & purificação , Penicillium/isolamento & purificação , Sphingomonas/isolamento & purificação , Staphylococcus/isolamento & purificação
10.
J Immunol Methods ; 135(1-2): 71-5, 1990 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-2273266

RESUMO

An indirect immunofluorescence microassay, which permits automated reading, has been employed for simple, rapid and objective detection of surface and intracellular antigens. Initially, the cells, spun in microplates, are fixed with glutaraldehyde (0.25% v/v in PBS). Following fixation, the cells can be stored at 4 degrees C for up to 2 weeks before being used in the immunofluorescence microassay. The fixed cells are then stained according to standard procedures using appropriate first and fluorescein-conjugated second antibodies. An automated and quantitative evaluation of the fluorescence intensity of the cell samples was achieved using the Titertek Fluoroskan II automatic reader. This microassay was shown to be suitable for the detection of the surface MAC1 antigen and intracellular v-myc protein in the GG2EE macrophage cell line.


Assuntos
Antígenos de Superfície/análise , Citoplasma/imunologia , Imunofluorescência , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Antígeno de Macrófago 1/análise , Macrófagos/imunologia , Proteína Oncogênica p55(v-myc)/análise
11.
J Neuroimmunol ; 58(1): 111-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7730446

RESUMO

In the present paper, we investigated the involvement of cryptococcal melanogenesis and macrophage nitric oxide (NO) production in the accomplishment of anticryptococcal activity by microglial effector cells, using the murine cell line BV-2. We demonstrate that the constitutive levels of anticryptococcal activity exerted by BV-2 cells is significantly enhanced upon interferon gamma plus lipopolysaccharide treatment. The phenomenon, which occurs with no enhancement of phagocytic activity, is associated with the production of high levels of NO and is abolished by addition of NG-monomethyl-L-arginine. Comparable patterns of results are observed employing either unopsonized or opsonized microbial targets, the latter microorganisms being markedly more susceptible to BV-2 cell antimicrobial activity. Furthermore, melanization of Cryptococcus neoformans significantly reduces its susceptibility to BV-2 antimicrobial activity, regardless of the fact that activated macrophages or opsonized microorganisms have been employed. In conclusion, our results provide evidence that NO-dependent events are involved in the fulfillment of anticryptococcal activity by activated microglial cells and that fungal melanization is a precious escamotage through which C. neoformans overcomes host defenses.


Assuntos
Arginina/análogos & derivados , Cryptococcus neoformans/imunologia , Interferon gama/farmacologia , Microglia/microbiologia , Óxido Nítrico/fisiologia , Fagocitose , Animais , Arginina/farmacologia , Linhagem Celular , Genes myc , Camundongos , Microglia/efeitos dos fármacos , Microglia/imunologia , Proteínas Oncogênicas v-raf , Fagocitose/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Proteínas Recombinantes , Retroviridae , Proteínas Oncogênicas de Retroviridae/genética , Transfecção , ômega-N-Metilarginina
12.
FEMS Immunol Med Microbiol ; 7(4): 289-95, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8136779

RESUMO

The present study was designed to establish the susceptibility of macrophage-mediated effector functions to tetanus toxin (TT). Using the murine macrophage cell line, GG2EE, generated in vitro by v-raf/v-myc oncogenes, we have previously provided evidence that TT selectively inhibits interferon gamma (IFN-gamma), but not basal, lysozyme activity. Here we show that while neither phagocytic nor candidacidal activities are affected by TT treatment, antitumoral activity is significantly impaired after exposure to TT. This phenomenon, which is dose-dependent, is fully ascribed to the holotoxin, as heat inactivated TT, C or A-B fragments result ineffective. Furthermore, C but not A-B fragment competes with TT in abrogating its inhibitory effects. Overall, these data indicate that TT is not a broad-spectrum, down-regulating signal on macrophage-mediated functions, thus implying that its toxic action is exerted on specific molecular targets.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Toxina Tetânica/farmacologia , Animais , Candida/imunologia , Linhagem Celular , Interferon gama/farmacologia , Macrófagos/imunologia , Camundongos
13.
FEMS Immunol Med Microbiol ; 9(3): 207-15, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7529080

RESUMO

In the present study, we compared four macrophage (M phi) cell lines from different anatomical origins for functional and secretory activities against the two morphogenetic forms of the fungus Candida albicans. We show that all the cell lines actively phagocytize the yeast and exert antimicrobial activity against both forms of Candida, although M phi of microglial origin are the most effective. When assessed for secretory properties, microglial M phi exhibit a peculiar pattern with respect to other M phi populations under either basal or stimulated conditions. In particular, only microglial M phi fail to respond to the hyphal form of the fungus (H-Candida), which instead acts as a potent tumor necrosis factor inducer in the other M phi cell lines. When exposed to H-Candida, microglial M phi are indistinguishable from other M phi in their ability to modulate specific surface adhesion molecules. In addition to strengthening the knowledge on functional heterogeneity among M phi, our data provide evidence on the peculiar behavior of microglial M phi. To what extent M phi heterogeneity may be related to tissue homeostasis is discussed.


Assuntos
Candida albicans/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Animais , Northern Blotting , Medula Óssea/imunologia , Encéfalo/imunologia , Linhagem Celular/imunologia , Linhagem Celular/metabolismo , Linhagem Celular/microbiologia , Citometria de Fluxo , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Cavidade Peritoneal/citologia , Fagocitose/fisiologia , RNA/isolamento & purificação , Fator de Necrose Tumoral alfa/análise
14.
Ann Chim ; 91(11-12): 785-93, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11836956

RESUMO

Preliminary results on limestone weathering caused by air pollution and microbial colonization are presented in this study. Outdoor exposure experimental assays were performed on Scaglia limestone samples. Samples were exposed in two areas in Perugia (Italy) that differ for degree of urban air pollution. At different times of exposure, ranging from 1 to 12 months, microbial contamination and textural modifications of sampled surfaces were evaluated by microbiological procedures, X-ray diffraction, and scanning electron microscopy. After one year of exposure a significant fungal colonization and the presence of weathering products (i.e. gypsum) were detected on sampled surfaces.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Carbonato de Cálcio/química , Cladosporium/crescimento & desenvolvimento , Rhodotorula/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Itália , Microscopia Eletrônica de Varredura , Difração de Raios X
15.
Bone Marrow Transplant ; 45(11): 1645-52, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20173782

RESUMO

T helper (Th) 17 cells have emerged as important mediators in infectious and inflammatory diseases and, recently, in transplant rejection. We analyzed the associations between five common genetic variants in the IL-23/Th17 signaling pathway, namely in IL17A, IL17F and IL23R genes, and clinical outcome in T cell-depleted allogeneic SCT (allo-SCT). In the multivariate analysis, variants in IL23R and IL17A genes were the most important prognostic factors. Thus, patient GA genotype at rs11209026 in IL23R was associated with improved overall survival (hazard ratio (HR)=0.48; P=0.028) and, in donor, with decreased risk of fungal infections (P=0.05). In contrast, patient TC and CC genotypes at rs8193036 in IL17A gene were associated with increased risk of CMV infection (HR=3.68; P=0.011) and patient acute GVHD (HR=7.08; P=0.008), respectively. These results suggest that genetic variants in the IL-23/Th17 inflammatory pathway are important prognostic factors for the clinical outcome of allo-SCT. Although validation studies are ultimately required, our results would suggest the potential usefulness of IL-23/Th17 genotyping in donor selection and patient evaluation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Interleucina-17/genética , Interleucina-23/genética , Depleção Linfocítica , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Criança , Intervalo Livre de Doença , Feminino , Genótipo , Humanos , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Linfócitos T/citologia , Adulto Jovem
17.
J Infect Dis ; 197(4): 618-21, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18275280

RESUMO

Toll-like receptors (TLRs) are important components of innate immunity. We investigated the association between polymorphisms in the TLR2, TLR4, and TLR9 genes and susceptibility to noninvasive forms of pulmonary aspergillosis. A significant association was observed between allele G on Asp299Gly (TLR4) and chronic cavitary pulmonary aspergillosis (odds ratio [OR], 3.46; P =.003). Susceptibility to allergic bronchopulmonary aspergillosis was associated with allele C on T-1237C (TLR9) (OR, 2.49; P =. 043). No particular polymorphism was associated with severe asthma with fungal sensitization. These findings reinforce the importance of innate immunity in the pathogenesis of different forms of aspergillosis.


Assuntos
Aspergilose Broncopulmonar Alérgica/imunologia , Aspergillus fumigatus/imunologia , Pneumopatias Fúngicas/imunologia , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/genética , Idoso , Aspergilose/genética , Aspergilose/imunologia , Aspergilose Broncopulmonar Alérgica/genética , Aspergillus fumigatus/patogenicidade , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Pneumopatias Fúngicas/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptor 2 Toll-Like/genética
18.
Med Mycol ; 43 Suppl 1: S181-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16110810

RESUMO

Efficient responses to fungi require different mechanisms of immunity. Dendritic cells (DCs) are uniquely able to decode the fungus-associated information and translate it into qualitatively different T helper (Th) immune responses. Murine and human DCs phagocytose conidia and hyphae of Aspergillus fumigatus through distinct recognition receptors. The engagement of distinct receptors translates into disparate downstream signaling events, ultimately affecting cytokine production and co-stimulation. Adoptive transfer of different types of DCs activates protective and non-protective Th cells as well as regulatory T cells, ultimately affecting the outcome of the infection in mice with invasive aspergillosis. The infusion of fungus-pulsed or RNA-transfected DCs also accelerates recovery of functional antifungal Th 1 responses in mice with allogeneic hematopoietic stem cell transplantation. Patients receiving T cell-depleted allogeneic hematopoietic stem cell transplantation are unable to develop antigen-specific T cell responses soon after transplant due to defective DC functions. Our results suggest that the adoptive transfer of DCs may restore immunocompetence in hematopoietic stem cell transplantation by contributing to the educational program of T cells. Thus, the remarkable furictional plasticity of DCs can be exploited for the deliberate targeting of cells and pathways of cell-mediated immunity in response to the fungus.


Assuntos
Aspergilose/imunologia , Aspergilose/terapia , Aspergillus fumigatus/imunologia , Células Dendríticas/imunologia , Células Dendríticas/transplante , Transferência Adotiva , Animais , Aspergilose/microbiologia , Aspergillus fumigatus/patogenicidade , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunoterapia , Camundongos , Vacinação
19.
Infect Immun ; 57(8): 2452-6, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2501219

RESUMO

This study was designed to evaluate the effects of tetanus toxin (TT) on lysozyme (LZM) activity by the GG2EE macrophage cell line. GG2EE cells spontaneously produced low amounts of LZM, which were mostly secreted into the culture medium. Upon treatment with various cytokines, GG2EE cells exhibited altered LZM activity. In particular, exposure of GG2EE cells to alpha/beta interferon (IFN-alpha/beta) reduced LZM activity, as opposed to treatment with gamma interferon (IFN-gamma) or colony-stimulating factor 1, which potentiated LZM activity. Spontaneous LZM activity of GG2EE cells was not susceptible to TT action; in contrast, when IFN-gamma- or colony-stimulating factor 1-susceptible cells were treated with TT, a significant reduction on LZM activity was observed. The TT inhibitory effect was dose dependent and manifested only after a 6-h incubation of GG2EE cells with TT. Treatment of GG2EE cells with heat-inactivated TT as well as Ibc- and B-IIb-TT-derived fragments was found to be ineffective, while pretreatment with B-IIb- but not with Ibc-TT-derived fragment abrogated the TT effect. Overall, these data indicate the existence of a specific TT-GG2EE cell interaction, leading to selective inhibition of cytokine-induced LZM activity.


Assuntos
Fatores Biológicos/farmacologia , Macrófagos/enzimologia , Muramidase/antagonistas & inibidores , Toxina Tetânica/farmacologia , Animais , Ligação Competitiva , Linhagem Celular , Fatores Estimuladores de Colônias/farmacologia , Citocinas , Interferon Tipo I/farmacologia , Interferon gama/farmacologia , Cinética , Camundongos , Peso Molecular , Fragmentos de Peptídeos/farmacologia , Toxina Tetânica/antagonistas & inibidores
20.
Infect Immun ; 61(9): 3605-10, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8359883

RESUMO

By using a nonneuronal cell system, evidence has previously been provided that tetanus toxin (TT) intoxication occurs in macrophages, impairing their secretory activity as well as their antitumoral activity. In particular, both secreted and total lysozyme (LZM) activities are reduced by TT treatment, provided that GG2EE macrophages have been preexposed to gamma interferon (IFN-gamma). In an attempt to provide insight into the molecular mechanisms underlying this phenomenon, we focused our attention on the levels of LZM-specific transcripts. GG2EE macrophages preexposed to IFN-gamma exhibited augmented levels of LZM-specific mRNA. Such an effect was detected 1 h after removal of IFN-gamma, peaked at 3 h, and gradually decreased with time in culture. Exposure of IFN-gamma-pretreated GG2EE macrophages to TT resulted in the prevention of the IFN-gamma-mediated upregulation of LZM mRNA levels. The phenomenon was mediated by the holotoxin (> or = 1 micrograms/ml) and abrogated by preexposure of the macrophages to the C fragment of TT. Protein kinase C (PKC) and Ca(2+)-calmodulin-dependent PK were likely involved in the IFN-gamma-mediated upregulation of LZM mRNA levels and biological activity, as assessed by PK inhibitors. Furthermore, PK inhibitors mimicked TT in impairing LZM activity of GG2EE macrophages, thus suggesting that impairment of PKC and/or the Ca(2+)-calmodulin-dependent PK pathway(s) may be one of the events involved in TT intoxication of macrophages.


Assuntos
Interferon gama/farmacologia , Macrófagos/efeitos dos fármacos , Muramidase/genética , RNA Mensageiro/análise , Toxina Tetânica/toxicidade , Animais , Linhagem Celular , Macrófagos/enzimologia , Camundongos , Camundongos Endogâmicos C3H , Inibidores de Proteínas Quinases , Proteínas Quinases/fisiologia , RNA Mensageiro/genética , Regulação para Cima
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