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1.
Medicina (B Aires) ; 76(3): 166-72, 2016.
Article in Spanish | MEDLINE | ID: mdl-27295706

ABSTRACT

The monogenic autoinflammatory diseases are rare, genetic disorders resulting in constitutive innate immune defects leading to excessive response to danger signals, spontaneous activation of inflammatory mediators or loss of inhibitory regulators. During the past 15 years, a growing number of monogenic inflammatory diseases have been described and their respective responsible genes identified. The proteins encoded by these genes are involved in the regulatory pathways of inflammation and are mostly expressed in cells of the innate immune system. Although a group of patients exhibit episodic systemic inflammation (periodic fevers), these disorders are mediated by continuous overproduction and release of pro-inflammatory mediators, notably IL-1ß, and are best considered as autoinflammatory diseases rather than periodic fevers. The most common autoinflammatory diseases are familial Mediterranean fever (FMF), TNF receptor-associated periodic syndrome (TRAPS), mevalonate kinase deficiency/hyperimmunoglobulin D syndrome (MKD/HIDS) and the cryopyrin-associated periodic syndromes (CAPS). Clinical features often include fever, cutaneous rash, serosal involvement and acute phase reactants. Autoantibodies are usually absent but may accompany certain syndromes. Diagnosis remains clinical and is based on the different phenotypic features. Genetic diagnosis is of utmost importance, but must be performed judiciously and interpreted cautiously. Treatment with biologic agents that block proinflammatory cytokines, particularly IL-1, has proved to be dramatically effective in many patients. Still, in many cases of autoinflammation no genetic abnormalities are detected and treatment remains suboptimal, raising the question of novel pathogenic mutations in unexplored genes and pathways.


Subject(s)
Hereditary Autoinflammatory Diseases/immunology , Hereditary Autoinflammatory Diseases/pathology , Fever/genetics , Fever/immunology , Fever/pathology , Fever/physiopathology , Hereditary Autoinflammatory Diseases/genetics , Hereditary Autoinflammatory Diseases/physiopathology , Humans , Interleukin-1beta/immunology , Interleukin-6/immunology , Mutation/immunology , Tumor Necrosis Factors/immunology
2.
Medicina (B.Aires) ; Medicina (B.Aires);76(3): 166-172, June 2016. ilus
Article in Spanish | LILACS | ID: biblio-841565

ABSTRACT

Las enfermedades autoinflamatorias monogénicas son desórdenes raros que resultan en defectos del sistema inmune innato, originando excesiva respuesta a señales de peligro, activación espontánea de vías inflamatorias o pérdida de reguladores inhibitorios. En los últimos 15 años un creciente número de enfermedades inflamatorias monogénicas han sido descriptas y sus respectivos genes responsables identificados. Las proteínas codificadas por estos genes están involucradas en las vías regulatorias de la inflamación y están expresadas fundamentalmente en las células del sistema inmune innato. Si bien un grupo de pacientes exhibe inflamación sistémica episódica (fiebres periódicas), estos desórdenes están mediados por una continua sobreproducción y liberación de mediadores pro-inflamatorios -especialmente la interleucina 1beta- y su conceptualización como enfermedades autoinflamatorias es preferible por sobre la de fiebres periódicas. Las enfermedades más frecuentes son fiebre mediterránea familiar (FMF), TRAPS, deficiencia de mevalonatocinasa/síndrome de hiper IgD (MKD/HIDS) y los síndromes periódicos asociados a criopirina (CAPS). Sus características clínicas frecuentemente incluyen fiebre, erupciones cutáneas, compromiso de serosas y reactantes de fase aguda. Los autoanticuerpos están usualmente ausentes pero pueden observarse en ciertos síndromes. El diagnóstico es clínico y se basa en las características fenotípicas. El diagnóstico genético es muy importante pero debe ser realizado de manera juiciosa e interpretado con cautela. El tratamiento con agentes biológicos que bloquean citocinas pro-inflamatorias, particularmente IL-1, ha demostrado ser efectivo en muchos pacientes. Sin embargo, en otros tantos casos no se descubren anormalidades genéticas y el tratamiento es subóptimo, planteando la posibilidad de mutaciones patogénicas en genes y vías aún no explorados.


The monogenic autoinflammatory diseases are rare, genetic disorders resulting in constitutive innate immune defects leading to excessive response to danger signals, spontaneous activation of inflammatory mediators or loss of inhibitory regulators. During the past 15 years, a growing number of monogenic inflammatory diseases have been described and their respective responsible genes identified. The proteins encoded by these genes are involved in the regulatory pathways of inflammation and are mostly expressed in cells of the innate immune system. Although a group of patients exhibit episodic systemic inflammation (periodic fevers), these disorders are mediated by continuous overproduction and release of pro-inflammatory mediators, notably IL-1β, and are best considered as autoinflammatory diseases rather than periodic fevers. The most common autoinflammatory diseases are familial Mediterranean fever (FMF), TNF receptor-associated periodic syndrome (TRAPS), mevalonate kinase deficiency/hyperimmunoglobulin D syndrome (MKD/HIDS) and the cryopyrin-associated periodic syndromes (CAPS). Clinical features often include fever, cutaneous rash, serosal involvement and acute phase reactants. Autoantibodies are usually absent but may accompany certain syndromes. Diagnosis remains clinical and is based on the different phenotypic features. Genetic diagnosis is of utmost importance, but must be performed judiciously and interpreted cautiously. Treatment with biologic agents that block proinflammatory cytokines, particularly IL-1, has proved to be dramatically effective in many patients. Still, in many cases of autoinflammation no genetic abnormalities are detected and treatment remains suboptimal, raising the question of novel pathogenic mutations in unexplored genes and pathways.


Subject(s)
Humans , Hereditary Autoinflammatory Diseases/immunology , Hereditary Autoinflammatory Diseases/pathology , Interleukin-6/immunology , Tumor Necrosis Factors/immunology , Interleukin-1beta/immunology , Hereditary Autoinflammatory Diseases/physiopathology , Hereditary Autoinflammatory Diseases/genetics , Fever/physiopathology , Fever/genetics , Fever/immunology , Fever/pathology , Mutation/immunology
3.
Rev. latinoam. enferm. (Online) ; 23(4): 603-610, July-Aug. 2015. tab, ilus
Article in English | LILACS, BDENF - Nursing | ID: lil-761705

ABSTRACT

AbstractObjective: to evaluate the effect of foot reflexology on feet impairment of people with type 2 diabetes mellitus.Method: this is a randomized, controlled and blind clinical trial. The sample was comprised by people with type 2 diabetes mellitus who, after being randomized into Treated group (n = 21) and Control group (n = 24), received guidelines on foot self-care. To the Treated Group it was also provided 12 sessions of foot reflexology. The scores of impairment indicators related to skin and hair, blood circulation, tissue sensitivity and temperature were measured by means of the instrument for assessing tissue integrity of the feet of people with diabetes mellitus. Chi-square test, Fisher exact test, Mann-Whitney test and regression analyzes were applied to the data, considering a significance level of 5% (P value <0.05).Results: participants who received the therapy showed better scores in some impairment indicators related to skin and hair (hair growth, elasticity/turgor, hydration, perspiration, texture and integrity of the skin/ skin peeling).Conclusion: the foot reflexology had a beneficial effect on feet impairment of people with type 2 diabetes mellitus, which makes it a viable therapy, deserving investment. This study was registered in the Brazilian Registry of Clinical Trials - RBR-8zk8sz.


ResumoObjetivo:avaliar o efeito da reflexologia podal no comprometimento dos pés de pessoas com diabetes mellitus tipo 2.Método:trata-se de um ensaio clínico, randomizado, controlado e mascarado. A amostra foi composta por pessoas com diabetes mellitus tipo 2 que, após serem randomizadas em grupo Tratado (n=21) e Controle (n=24), receberam orientações de autocuidado com os pés. Ao Grupo Tratado também foram fornecidas 12 sessões de reflexologia podal. Foram mensurados os escores de comprometimento de indicadores relacionados à pele e pelos, circulação sanguínea, sensibilidade e temperatura tissular por meio do Instrumento para avaliação da integridade tissular dos pés de pessoas com diabetes mellitus. Aos dados foram aplicados os testes Qui-Quadrado, Exato de Fisher, Mann-Whitney e Análises de regressão, considerando-se nível de significância de 5% (Valor P<0,05).Resultados:os participantes que receberam a terapia apresentaram melhores escores de comprometimento em alguns indicadores relacionados à pele e pelos (crescimento de pelos, elasticidade/tugor, hidratação, transpiração, textura e integridade da pele/descamação cutânea).Conclusão:a reflexologia podal apresentou efeito benéfico sobre o comprometimento dos pés de pessoas com diabetes mellitus tipo 2, o que a torna uma terapia viável e que merece investimento. Este estudo foi registrado no Registro Brasileiro de Ensaios Clínicos - RBR-8zk8sz.


ResumenObjetivo:evaluar el efecto de la reflexología podal en el comprometimiento de los pies de personas con diabetes mellitus tipo 2.Método:se trata de un ensayo clínico, aleatorio, controlado y enmascarado. La muestra estuvo compuesta por personas con diabetes mellitus tipo 2 que, después de ser tratadas aleatoriamente en los grupos Tratado (n=21) y Control (n=24), recibieron orientaciones de autocuidado de los pies. También, al Grupo Tratado se le suministraron 12 sesiones de reflexología podal. Fueron medidos los puntajes de comprometimiento de indicadores relacionados a la piel y pelos, circulación sanguínea, sensibilidad y temperatura tisular por medio de instrumento para evaluación de la integridad del tejido de los pies de personas con diabetes mellitus. Los datos fueron sometidos a las pruebas Chi-cuadrado, Exacta de Fisher, Mann-Whitney y Análisis de regresión, considerando un nivel de significación de 5% (Valor p<0,05).Resultados:los participantes que recibieron la terapia presentaron mejores puntajes de comprometimiento en algunos indicadores relacionados a la piel y pelos (crecimiento de pelos, elasticidad/turgencia, hidratación, transpiración, textura e integridad de la piel/descamación cutánea).Conclusión:la reflexología podal presentó efecto benéfico sobre el comprometimiento de los pies de personas con diabetes mellitus tipo 2, lo que la torna una terapia viable y que merece inversiones. Este estudio fue registrado en el Registro Brasileño de Ensayos Clínicos - RBR-8zk8sz.


Subject(s)
Animals , Female , Mice , Antibodies, Monoclonal, Murine-Derived/pharmacology , /immunology , /immunology , Graft Survival/drug effects , Heart Transplantation , Lymphocyte Function-Associated Antigen-1/immunology , Membrane Glycoproteins/immunology , Tumor Necrosis Factors/immunology , Allografts , Graft Rejection/immunology , Graft Rejection/pathology , Graft Rejection/prevention & control , Graft Survival/immunology , Intercellular Adhesion Molecule-1/immunology , Mice, Inbred BALB C , Skin Transplantation , Time Factors
4.
PLoS One ; 7(7): e40142, 2012.
Article in English | MEDLINE | ID: mdl-22768337

ABSTRACT

The pineal gland, a circumventricular organ, plays an integrative role in defense responses. The injury-induced suppression of the pineal gland hormone, melatonin, which is triggered by darkness, allows the mounting of innate immune responses. We have previously shown that cultured pineal glands, which express toll-like receptor 4 (TLR4) and tumor necrosis factor receptor 1 (TNFR1), produce TNF when challenged with lipopolysaccharide (LPS). Here our aim was to evaluate which cells present in the pineal gland, astrocytes, microglia or pinealocytes produced TNF, in order to understand the interaction between pineal activity, melatonin production and immune function. Cultured pineal glands or pinealocytes were stimulated with LPS. TNF content was measured using an enzyme-linked immunosorbent assay. TLR4 and TNFR1 expression were analyzed by confocal microscopy. Microglial morphology was analyzed by immunohistochemistry. In the present study, we show that although the main cell types of the pineal gland (pinealocytes, astrocytes and microglia) express TLR4, the production of TNF induced by LPS is mediated by microglia. This effect is due to activation of the nuclear factor kappa B (NF-kB) pathway. In addition, we observed that LPS activates microglia and modulates the expression of TNFR1 in pinealocytes. As TNF has been shown to amplify and prolong inflammatory responses, its production by pineal microglia suggests a glia-pinealocyte network that regulates melatonin output. The current study demonstrates the molecular and cellular basis for understanding how melatonin synthesis is regulated during an innate immune response, thus our results reinforce the role of the pineal gland as sensor of immune status.


Subject(s)
Melatonin/biosynthesis , Neuroglia/metabolism , Paracrine Communication/physiology , Pineal Gland/metabolism , Receptors, Tumor Necrosis Factor, Type I/biosynthesis , Tumor Necrosis Factors/metabolism , Animals , Cells, Cultured , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , Lipopolysaccharides/pharmacology , Male , Melatonin/immunology , Neuroglia/cytology , Neuroglia/immunology , Paracrine Communication/drug effects , Pineal Gland/cytology , Pineal Gland/immunology , Rats , Rats, Wistar , Receptors, Tumor Necrosis Factor, Type I/immunology , Tumor Necrosis Factors/immunology
5.
Rio de Janeiro; s.n; 2009. xvi,91 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-556622

ABSTRACT

As proteínas da família do Fator de Necrose Tumoral (TNF) possuem papel importante na indução de processos biológicos como proliferação, diferenciação, sobrevivência e morte celular. APRIL (ligante indutor de proliferação) é uma citocina desta família que promove proliferação e sobrevivência tumoral, modulando, também, a atividade de linfócitos B, favorecendo a sobrevivência e produção de anticorpos. Por outro lado, seus efeitos em linfócitos T ainda não pouco conhecidos. APRIL interage com os receptores BCMA e TACI expressos em linfócitos. Além destes, APRIL pode ligar-se a proteoglicanas de heparan-sulfato (HSPG) nas superfícies celulares. Camundongos transgênicos para APRIL que expressam a proteína em excesso desenvolvem neoplasia associada às células B-1. Em análise preliminar por imunohistoquímica encontramos um aumento de células B220+ no timo destes animais comparado aos controles. O timo é o órgão linfóide primário onde ocorre a maturação de linfócitos T, processo altamente dependente da migração dos timócitos no microambiente tímico. Para isto, os timócitos interagem com células epiteliais tímicas (TEC) e com uma rede de matriz extracelular complexa, que apresenta entre outros componentes, fibronectina e laminina. No entanto, os efeitos de APRIL no timo ainda não são conhecidos. Neste sentido, nosso objetivo foi estudar o efeito de APRIL na migração de timócitos de camundongos normais através de ensaios de migração em câmaras de transwell. Inicialmente, investigamos o impacto de APRIL na sobrevivência e proliferação de timócitos, porém, não encontramos alterações após o tratamento in vitro com a proteína recombinante. Por outro lado, os ensaios de migração ex vivo revelaram que APRIL possui efeito quimiorrepulsor, provavelmente, em conseqüência da diminuição da adesão dos timócitos conforme análise do co-cultivo com linhagens de TEC. A modulação destes eventos não estava relacionada com alteração do perfil de expressão dos receptores para fibronectina e laminina (VLA-4/VLA-5 e VLA-6) nas subpopulações de timócitos. Além disso, o efeito quimiorrepulsor de APRIL foi potencializado por CXCL12 e laminina (mas não por fibronectina). E ainda, os timócitos, ao contrário das TEC, não expressam receptor TACI. No entanto, o pré tratamento com heparina bloqueia parcialmente o efeito de APRIL na migração dos timócitos, sugerindo que este seja mediado pela interação com HSPG. Assim, concluímos que APRIL estimule a migração de timócitos, e module negativamente a adesão celular, através da interação com HSPG.


Subject(s)
Allergy and Immunology , Tumor Necrosis Factors/immunology , Mice, Transgenic
6.
Int Wound J ; 5(4): 530-9, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19006574

ABSTRACT

Lower extremity ulceration is one of the serious and long-term diabetic complications rendering a significant social burden in terms of amputation and quality-of-life reduction. Diabetic patients experience a substantial wound-healing deficit. These lesions are featured by an exaggerated and prolonged inflammatory reaction with a significant impairment in local bacterial invasion control. Experimental and clinical evidences document the deleterious consequences of the wound's pro-inflammatory phenotype for the repair process. From a biochemical standpoint, hyperinflammation favours wound matrix degradation, thus, amplifying a pre-existing granulation tissue productive cells' invasiveness and recruitment deficit. Tumour necrosis factor perpetuates homing of inflammatory cells, triggers pro-apoptotic genes and impairs reepithelialisation. Advanced glycation end-products act in concert with inflammatory mediators and commit fibroblasts and vascular cells to apoptosis, contributing to granulation tissue demise. Therapeutic approaches aimed to downregulate hyperinflammation and/or attenuate glucolipotoxicity may assist in diabetic wound healing by dismantling downstream effectors. These medical interventions are demanded to reduce amputations in an expanding diabetic population.


Subject(s)
Diabetic Foot/immunology , Glycation End Products, Advanced/immunology , Matrix Metalloproteinases/immunology , Tumor Necrosis Factors/immunology , Wound Healing/immunology , Apoptosis/immunology , Apoptosis Regulatory Proteins/immunology , Diabetic Foot/prevention & control , Down-Regulation/drug effects , Down-Regulation/immunology , Fibroblasts/immunology , Glycation End Products, Advanced/antagonists & inhibitors , Granulation Tissue/immunology , Humans , Inflammation , Tumor Necrosis Factor Inhibitors , Wound Healing/drug effects
7.
Eur J Immunol ; 36(2): 345-53, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16421947

ABSTRACT

The kinetics of macrophage and T lymphocyte apoptosis were determined in a well-characterized mouse model of pulmonary tuberculosis, comparing strains of intermediate (H37Rv) and high virulence (Beijing strain, code 9501000). Both strains induced a high percentage of apoptotic activated macrophages at days 1 and 3 post infection, although this was twofold lower in Beijing-infected mice. Progressive pneumonia started at day 14 (Beijing) or 21 (H37Rv) post infection. Pneumonic areas contained numerous macrophages with vacuolated cytoplasm (VM). In H37Rv infection few VM were apoptotic (8.7% at day 60), and the percentage was even lower in Beijing infection (1.4% at day 28). A high percentage of VM expressed the anti-apoptotic molecule Bcl-2 (H37Rv, 83%; Beijing, 95%). Both strains induced a progressive increase of apoptotic Th1 lymphocytes, peaking at day 60 in H37Rv infection, or 28 in Beijing infection. The peak was twofold higher in the latter. VM had strong FasL immunostaining, and confocal microscopy showed numerous apoptotic Th1 cells closely associated with them, suggesting that VM might induce apoptosis of Th1 cells. These results support the hypothesis that apoptosis of macrophages is associated with protection, while apoptosis of Th1 cells favors disease progression, and is related to the virulence of the mycobacterial strain.


Subject(s)
Apoptosis/immunology , Macrophages, Alveolar/immunology , Mycobacterium tuberculosis/immunology , Th1 Cells/immunology , Th2 Cells/immunology , Tuberculosis, Pulmonary/immunology , Animals , Cytoplasm/immunology , Cytoplasm/microbiology , Cytoplasm/pathology , Disease Models, Animal , Fas Ligand Protein , Immunohistochemistry , Macrophages, Alveolar/microbiology , Macrophages, Alveolar/pathology , Membrane Glycoproteins/immunology , Mice , Mice, Inbred BALB C , Microscopy, Confocal , Mycobacterium tuberculosis/pathogenicity , Pneumonia/immunology , Pneumonia/microbiology , Pneumonia/pathology , Proto-Oncogene Proteins/immunology , Proto-Oncogene Proteins c-bcl-2 , Species Specificity , Th1 Cells/microbiology , Th1 Cells/pathology , Th2 Cells/microbiology , Th2 Cells/pathology , Tuberculosis, Pulmonary/microbiology , Tuberculosis, Pulmonary/pathology , Tumor Necrosis Factors/immunology
8.
Virus Res ; 116(1-2): 91-7, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16219382

ABSTRACT

Yellow fever is an infectious, non-contagious disease caused by an RNA virus of the family Flaviviridae, which is transmitted to man by the bite of hematophagous mosquitoes. Infection with the yellow fever virus can progress with lesions in the heart, kidneys, central nervous system, and liver. In the liver, the histopathological picture is characterized by necrosis, steatosis and hepatocyte apoptosis, with a preferential midzone distribution. In the present study, liver samples from fatal patients with yellow fever were analyzed. The histopathological pattern was characterized by steatosis, lytic necrosis and hepatocyte apoptosis associated with a moderate mononuclear inflammatory infiltrate. The inflammatory component mainly consisted of CD4+ T lymphocytes, followed by CD8+ T lymphocytes, which showed a preferential portal and midzone distribution. Immunoreactivity to Fas ligand was mainly observed in hepatocytes of the midzone region. Based on these findings, we conclude that lymphocytes play an important role in the genesis of hepatic lesions in severe yellow fever, inducing hepatocyte apoptosis through the binding to Fas receptors. However, further studies are necessary to investigate the participation of other immune factors and to quantify the role of the cytotoxic cellular response in the lesion evolution during the course of disease in the liver.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Membrane Glycoproteins/immunology , Tumor Necrosis Factors/immunology , Yellow Fever/immunology , Adolescent , Adult , Aged , Apoptosis , Child , Child, Preschool , Fas Ligand Protein , Fatty Liver/pathology , Female , Humans , Immunohistochemistry , Infant , Liver/pathology , Male , Middle Aged , Necrosis , Photomicrography
9.
J Leukoc Biol ; 78(4): 853-61, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16046554

ABSTRACT

Monocytes (Mo) mediate central functions in inflammation and immunity. Different subpopulations of Mo with distinct phenotype and functional properties have been described. Here, we investigate the phenotype and function of peripheral Mo from children with hemolytic uremic syndrome (HUS). For this purpose, blood samples from patients in the acute period of HUS (HUS AP) were obtained on admission before dialysis and/or transfusion. The Mo phenotypic characterization was performed on whole blood by flow cytometry, and markers associated to biological functions were selected: CD14 accounting for lipopolysaccharide (LPS) responsiveness, CD11b for adhesion, Fc receptor for immunoglobulin G type I (FcgammaRI)/CD64 for phagocytosis and cytotoxicity, and human leukocyte antigen (HLA)-DR for antigen presentation. Some of these functions were also determined. Moreover, the percentage of CD14+ CD16+ Mo was evaluated. We found that the entire HUS AP Mo population exhibited reduced CD14, CD64, and CD11b expression and decreased LPS-induced tumor necrosis factor production and Fcgamma-dependent cytotoxicity. HUS AP showed an increased percentage of CD14+ CD16+ Mo with higher CD16 and lower CD14 levels compared with the same subset from healthy children. Moreover, the CD14++ CD16- Mo subpopulation of HUS AP had a decreased HLA-DR expression, which correlated with severity. In conclusion, the Mo population from HUS AP patients presents phenotypic and functional alterations. The contribution to the pathogenesis and the possible scenarios that led to these changes are discussed.


Subject(s)
Antigens, Differentiation/immunology , Fetal Blood/immunology , Hemolytic-Uremic Syndrome/immunology , Hemolytic-Uremic Syndrome/physiopathology , Monocytes/immunology , Cell Count , Child, Preschool , Cytotoxicity, Immunologic , Flow Cytometry , Hemolytic-Uremic Syndrome/diagnosis , Humans , Immunoglobulin Fc Fragments/immunology , Infant , Lipopolysaccharides/pharmacology , Phenotype , Tumor Necrosis Factors/immunology
10.
São Paulo; s.n; 2005. 182 p. ilus, tab.
Thesis in Portuguese | LILACS, Inca | ID: lil-553340

ABSTRACT

A infecção persistente por alguns tipos de HPV de alto risco (ex. tipos 16 e 18), é o principal fator de risco para o desenvolvimento de neoplasias intraepiteliais cervicais e lesões precursoras do carcinoma do colo uterino. Diversos estudos sugerem que a resposta imune mediada por células é fundamental para o controle e eliminação das infecções por estes e outros vírus. Um dos principais mediadores/reguladores deste tipo de resposta é o fator de necrose tumoral (TNF)... Estes dados sugerem que a aquisição de resistência à este fator é um evento importante na carcinogênese mediada por HPV. No entanto, os eventos moleculares associados ao efeito diferencial do TNF nestas linhagens são, até o momento, desconhecidos. No presente estudo, foram analisados os níveis de expressão de expressão de algumas proteínas envolvidas na via de ativação do fator NF-kB. Utilizando um anticorpo anti-IkBα, foi detectada uma proteína de aproximadamente 20KDa, induzida após 12 horas de tratamento com TNF e atingindo altos níveis de expressão em torno das 60 horas de tratamento... A expressão diferencial de alguns genes comuns nas células sensíveis ao efeito antiproliferativo do TNF, contrariamente das células resistentes, foi identificada. A expressão destes genes está relacionada à processos biológicos, como, resposta imunológica e inflamatória, proliferação e diferenciação celular e controle da transdução de sinal de diversas vias. A identificação de genes e proteínas cruciais nestes eventos, permitirá avanços no controle da infecção por HPV, além de contribuir para a eventual caracterização de marcadores moleculares na progressão tumoral do câncer cervical...(AU)


Persistent infection by some high risk HPV types (ie: types 16 and 18) is the main risk factor for the development of cervical intraepithelial neoplasia and the precursor lesions of cervical cancer. Many studies suggest that cellmediated immunity is important for viral infection contrai and clearence. Tumor necrosis factor (TNF) is one of the main mediators/regulators of inflammatory response. TNF has a potent anti-proliferative effect on normal and HPV16 immortalized keratinocytes (HF698). On the other hand, HPV-18 immortalized keratinocytes (HF18Nco) and severa! cervical carcinomaderived cell lines, are resistant to TNF. These observations suggest that the acquisition of TNF-resistance may constitute an important step in HPV mediated carcinogenesis. However, the molecular basis of this difference is not well understood. In the present study, we analyzed the effect of TNF on NF-KB pathway activation. Using an anti-IKBa antibody, we detected a protein of 20 kDa induced after 12 hours of treatment with TNF. This protein reached higher leveis of expression after 60 hours of treatment. Besides, we found that this protein is constitutively express in the HPV16-immortalized cell line. Severa! experiments are being conducted in arder to identify this protein. Furthermore, we addressed the effect of 3 and 60 hours of TNF treatment on global gene expression of primary human keratinocytes and two HPV-immortalized keratinocytes-derived cell !ines. We observed the differential expression of severa! genes common to both TNF-sensitive cell lines. On the other hand, this was not observed in the TNF-resistant cell line. These genes are involved in immune and inflammatory response, cell proliferation and differentiation and 1n signal transduction contrai. Understanding the mechanisms of host response regulation, as well as the identification of new genes and proteins involved in its regulation, may provide new strategies for HPV infection contrai (AU)


Subject(s)
Humans , Female , Oligonucleotide Array Sequence Analysis , Cervix Uteri , Tumor Necrosis Factors , Papillomavirus Infections , Papillomavirus Infections/immunology , Keratinocytes , Cervix Uteri/injuries , Tumor Necrosis Factors/immunology
11.
Int. j. lepr. other mycobact. dis ; 69(3): 249-250, Sept., 2001. tab
Article in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1227058
12.
Int. j. lepr. other mycobact. dis ; 68(2): 156-166, Jun., 2000. ilus, graf
Article in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1226944

ABSTRACT

In the present study, the experimental model of Mycobacterium leprae infection in the foot pads of BALB/c mice was used to investigate the effects of BCG administration on tumor necrosis factor-alpha (TNF-alpha) production and granuloma development. It was observed that mice intravenously infected with BCG 7 months after M. leprae inoculation into the foot pads presented a more effective mycobacteria clearance, revealed by a significant reduction of BCG-colony forming units in the spleen and by the reduction of acid-fast bacilli (AFB) in the foot pads. BCG infection at the peak of M. leprae infection also modulated the granulomatous response to M. leprae by converting mononuclear granulomas into an epithelioid-cell granuloma. Furthermore, lower TNF-alpha serum levels were detected in M. leprae-infected mice when compared to mice infected with M. leprae + BCG. An analysis of the TNF-alpha gene expression in the spleen by semiquantitative reverse transcription-polymerase chain reactions (RT-PCR) demonstrated that co-infection with BCG induced an earlier expression of TNF-alpha mRNA than in M. leprae-infected mice. The numbers of TNF-alpha-positive cells and apoptotic cells were also enhanced in epithelioid versus non-epithelioid granulomas. As a whole, the data suggest that co-infection of M. leprae-infected mice with BCG modulates TNF-alpha synthesis which, in turn, leads to induction of protective epithelioid granuloma formation in the foot pads and subsequent mycobacterial clearance. Macrophage differentiation into epithelioid cells, in association with the enhancement of TNF-alpha production at the granuloma site, may represent a triggering signal that induced apoptosis in these cells, leading to mycobacterial elimination. Moreover, the rate of apoptosis in epithelioid granulomas may well be related to the extent of immunopathologically mediated tissue damage.


Subject(s)
Animals , Mice , Mice, Inbred BALB C/genetics , Mice, Inbred BALB C/immunology , Tumor Necrosis Factors/genetics , Tumor Necrosis Factors/immunology , Mycobacterium leprae/immunology , BCG Vaccine/therapeutic use
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