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1.
Osteoarthritis Cartilage ; 22(4): 578-85, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24508775

RESUMO

OBJECTIVE: Investigate a role for calcitonin gene-related peptide (CGRP) in osteoarthritis (OA)-related pain. DESIGN: Neutralizing antibodies to CGRP were generated de novo. One of these antibodies, LY2951742, was characterized in vitro and tested in pre-clinical in vivo models of OA pain. RESULTS: LY2951742 exhibited high affinity to both human and rat CGRP (KD of 31 and 246 pM, respectively). The antibody neutralized CGRP-mediated induction of cAMP in SK-N-MC cells in vitro and capsaicin-induced dermal blood flow in the rat. Neutralization of CGRP significantly reduced pain behavior as measured by weight bearing differential in the rat monoiodoacetate model of OA pain in a dose-dependent manner. Moreover, pain reduction with neutralization of CGRP occurred independently of prostaglandins, since LY2951742 and NSAIDs worked additively in the NSAID-responsive version of the model and CGRP neutralization remained effective in the NSAID non-responsive version of the model. Neutralization of CGRP also provided dose-dependent and prolonged (>60 days) pain reduction in the rat meniscal tear model of OA after only a single injection of LY2951742. CONCLUSIONS: LY2951742 is a high affinity, neutralizing antibody to CGRP. Neutralization of CGRP is efficacious in several OA pain models and works independently of NSAID mechanisms of action. LY2951742 holds promise for the treatment of pain in OA patients.


Assuntos
Anticorpos Neutralizantes/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Dor/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Peptídeos Catiônicos Antimicrobianos , Catelicidinas/metabolismo , Modelos Animais de Doenças , Humanos , Masculino , Ratos , Ratos Endogâmicos Lew , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea
2.
Neuroscience ; 228: 271-82, 2013 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-23098803

RESUMO

BACKGROUND: Calcitonin gene-related peptide (CGRP) is a powerful pro-inflammatory mediator thought to play a significant role in the development of inflammation and pain. We investigated the role of CGRP in trigeminal inflammatory pain by determining the ability of a monoclonal antibody to CGRP to modify central Fos expression in response to stimulation of the inflamed ferret tooth pulp. We also assessed the effect of the antibody on pulpal inflammation. METHODS: Ten adult ferrets were prepared under anaesthesia to allow stimulation of the upper and lower left canine pulps, recording from the digastric muscle and intravenous injections at subsequent experiments. In all animals, pulpal inflammation was induced by introducing human caries into a deep buccal cavity. Four days later animals were treated intravenously with either CGRP antibody (n=5) or vehicle (n=5). After a further 2 days animals were re-anaesthetised and the tooth pulps stimulated at 10 times jaw-opening reflex threshold. Brainstems and tooth pulps were processed immunohistochemically for Fos and the common leucocyte marker CD45, respectively. RESULTS: Fos was expressed in ipsilateral trigeminal subnuclei caudalis (Vc) and oralis (Vo). Significantly fewer Fos-positive nuclei were present within Vc of CGRP antibody-treated animals (p=0.003 vs vehicle-treated). Mean percentage area of staining for CD45 was significantly less in antibody-treated animals (p=0.04 vs vehicle-treated). CONCLUSIONS: This is the first direct evidence that sequestration of CGRP has anti-inflammatory and putative analgesic effects. Previous studies using this Fos model have demonstrated that it is able to predict clinical analgesic efficacy. Thus these data indicate that this antibody may have analgesic effects in dental pain and other types of inflammatory-mediated transmission, and suggest that this is in part due to peripheral anti-inflammatory effects.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Anticorpos Monoclonais/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/antagonistas & inibidores , Peptídeo Relacionado com Gene de Calcitonina/imunologia , Medição da Dor/métodos , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Polpa Dentária/imunologia , Polpa Dentária/metabolismo , Feminino , Furões , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/terapia , Resultado do Tratamento
3.
Oncogene ; 29(38): 5299-310, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20622903

RESUMO

The functional relationship and cross-regulation between autophagy and apoptosis is complex. In this study we show that the high-mobility group box 1 protein (HMGB1) is a redox-sensitive regulator of the balance between autophagy and apoptosis. In cancer cells, anticancer agents enhanced autophagy and apoptosis, as well as HMGB1 release. HMGB1 release may be a prosurvival signal for residual cells after various cytotoxic cancer treatments. Diminished HMGB1 by short hairpin RNA transfection or inhibition of HMGB1 release by ethyl pyruvate or other small molecules led predominantly to apoptosis and decreased autophagy in stressed cancer cells. In this setting, reducible HMGB1 binds to the receptor for advanced glycation end products (RAGEs), but not to Toll-like receptor 4, induces Beclin1-dependent autophagy and promotes tumor resistance to alkylators (melphalan), tubulin disrupting agents (paclitaxel), DNA crosslinkers (ultraviolet light) and DNA intercalators (oxaliplatin or adriamycin). On the contrary, oxidized HMGB1 increases the cytotoxicity of these agents and induces apoptosis mediated by the caspase-9/-3 intrinsic pathway. HMGB1 release, as well as its redox state, thus links autophagy and apoptosis, representing a suitable target when coupled with conventional tumor treatments.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Proteína HMGB1/fisiologia , Neoplasias/patologia , Antineoplásicos/farmacologia , Proteína HMGB1/metabolismo , Oxirredução
4.
J Immunol ; 167(8): 4172-9, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11591737

RESUMO

Immature B cells display increased sensitivity to tolerance induction compared with their mature counterparts. The molecular mechanisms underlying these differences are poorly defined. In this study, we demonstrate unique maturation stage-dependent differences in B cell Ag receptor (BCR) signaling, including BCR-mediated calcium mobilization responses. Immature B cells display greater increases in intracellular calcium concentrations following Ag stimulation. This has consequences for the induction of biologically relevant responses: immature B cells require lower Ag concentrations for activation than mature B cells, as measured by induction of receptor editing and CD86 expression, respectively. BCR-induced tyrosine phosphorylation of CD79a, Lyn, B cell linker protein, and phospholipase Cgamma2 is enhanced in immature B cells and they exhibit greater capacitative calcium entry in response to Ag. Moreover, B cell linker protein, Bruton's tyrosine kinase, and phospholipase Cgamma2, which are crucial for the induction of calcium mobilization responses, are present at approximately 3-fold higher levels in immature B cells, potentially contributing to increased mobilization of calcium. Consistent with this possibility, we found that the previously reported lack of inositol-1,4,5-triphosphate production in immature B cells may be explained by enhanced inositol-1,4,5-triphosphate breakdown. These data demonstrate that multiple mechanisms guarantee increased Ag-induced mobilization of calcium in immature B cells and presumably ensure elimination of autoreactive B cells from the repertoire.


Assuntos
Linfócitos B/imunologia , Células-Tronco Hematopoéticas/imunologia , Tolerância Imunológica , Ativação Linfocitária , Receptores de Antígenos de Linfócitos B/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos CD/metabolismo , Antígenos CD79 , Cálcio/metabolismo , Proteínas de Transporte , Inositol 1,4,5-Trifosfato/metabolismo , Isoenzimas/metabolismo , Camundongos , Camundongos Transgênicos , Fosfolipase C gama , Fosfoproteínas , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Quinases da Família src/metabolismo
5.
Immunity ; 14(1): 33-43, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11163228

RESUMO

Available evidence indicates that B cell tolerance is attained by receptor editing, anergy, or clonal deletion. Here, we describe a p-azophenylarsonate (Ars)-specific immunoglobulin transgenic mouse in which B cells become anergic as a consequence of cross-reaction with autoantigen in the bone marrow. Developing bone marrow B cells show no evidence of receptor editing but transiently upregulate activation markers and appear to undergo accelerated development. Mature B cells are present in normal numbers but are refractory to BCR-mediated induction of calcium mobilization, tyrosine phosphorylation, and antibody responses. Activation marker expression and acquisition of the anergic phenotype is prevented in bone marrow cultures by monovalent hapten. In this model, it appears that induction of anergy in B cells can be prevented by monovalent hapten competing with autoantigen for the binding site.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Anergia Clonal/imunologia , Haptenos/imunologia , Imunoglobulinas/imunologia , Ativação Linfocitária/imunologia , Alelos , Animais , Biomarcadores , DNA de Cadeia Simples/imunologia , Expressão Gênica , Hemocianinas/imunologia , Cadeias delta de Imunoglobulina/genética , Cadeias delta de Imunoglobulina/imunologia , Cadeias kappa de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/imunologia , Cadeias mu de Imunoglobulina/genética , Cadeias mu de Imunoglobulina/imunologia , Imunoglobulinas/genética , Camundongos , Camundongos Transgênicos , Transgenes , p-Azobenzenoarsonato/imunologia
6.
Digestion ; 62(1): 14-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10899720

RESUMO

BACKGROUND: An abnormal immune response may play a pathogenetic role in chronic pancreatitis. However, to date characterization of the systemic immunological changes in patients with chronic pancreatitis has not been undertaken. METHODS: Lymphocyte phenotypes and proliferation ((3)H-thymidine) after stimulation with mitogens and interleukin-2 were studied in peripheral mononuclear cells from 11 patients with chronic pancreatitis (alcohol-induced n = 6; idiopathic pancreatitis n = 5). The natural killer cell activity was investigated in a (51)Cr release cytotoxicity assay. In vitro cytokine release of stimulated mononuclear cells was measured. RESULTS: Flow cytometric studies showed a significant decrease in the percentage of circulating CD8+, CD56+ and CD25+ cells in patients with chronic pancreatitis independent of the etiology. Comparing all patients with chronic pancreatitis to controls, the proliferation rate was not significantly increased, but patients with pain (n = 5) showed increased proliferation in comparison to patients without pain (n = 6). No significant difference in natural killer cytotoxicity was observed. The in vitro release of tumor necrosis factor-alpha and interleukin-10 by stimulated mononuclear cells was increased. CONCLUSIONS: Chronic pancreatitis is accompanied by systemic immune dysregulation. The observed changes in peripheral mononuclear cells reveal additional evidence that the cell-mediated immune response may contribute to the development of pain and tissue destruction in chronic pancreatitis.


Assuntos
Subpopulações de Linfócitos , Pancreatite/imunologia , Adulto , Doença Crônica , Feminino , Citometria de Fluxo , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Pancreatite/patologia , Fenótipo
7.
J Exp Med ; 191(9): 1545-54, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10790429

RESUMO

Although the Src homology 2 domain-containing 5' inositol phosphatase (SHIP) is a well-known mediator of inhibitory signals after B cell antigen receptor (BCR) coaggregation with the low affinity Fc receptor, it is not known whether SHIP functions to inhibit signals after stimulation through the BCR alone. Here, we show using gene-ablated mice that SHIP is a crucial regulator of BCR-mediated signaling, B cell activation, and B cell development. We demonstrate a critical role for SHIP in termination of phosphatidylinositol 3,4,5-triphosphate (PI[3,4,5]P(3)) signals that follow BCR aggregation. Consistent with enhanced PI(3,4,5)P(3) signaling, we find that splenic B cells from SHIP-deficient mice display enhanced sensitivity to BCR-mediated induction of the activation markers CD86 and CD69. We further demonstrate that SHIP regulates the rate of B cell development in the bone marrow and spleen, as B cell precursors from SHIP-deficient mice progress more rapidly through the immature and transitional developmental stages. Finally, we observe that SHIP-deficient B cells have increased resistance to BCR-mediated cell death. These results demonstrate a central role for SHIP in regulation of BCR signaling and B cell biology, from signal driven development in the bone marrow and spleen, to activation and death in the periphery.


Assuntos
Linfócitos B/imunologia , Monoéster Fosfórico Hidrolases/metabolismo , Domínios de Homologia de src , Animais , Medula Óssea/crescimento & desenvolvimento , Morte Celular , Capeamento Imunológico , Ativação Linfocitária , Camundongos , Camundongos Mutantes , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Baço/crescimento & desenvolvimento
8.
Ann Sci ; 57(1): 1-25, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11624166

RESUMO

A prominent feature of late nineteenth-century psychology was its intense preoccupation with precision. Precision was at once an ideal and an argument: the quest for precision helped psychology to establish its status as a mature science, sharing a characteristic concern with the natural sciences. We will analyse how psychologists set out to produce precision in 'mental chronometry', the measurement of the duration of psychological processes. In his Leipzig laboratory, Wundt inaugurated an elaborate research programme on mental chronometry. We will look at the problem of calibration of experimental apparatus and will describe the intricate material, literary, and social technologies involved in the manufacture of precision. First, we shall discuss some of the technical problems involved in the measurement of ever shorter time-spans. Next, the Cattell-Berger experiments will help us to argue against the received view that all the precision went into the hardware, and practically none into the social organization of experimentation. Experimenters made deliberate efforts to bring themselves and their subjects under a regime of control and calibration similar to that which reigned over the experimental machinery. In Leipzig psychology, the particular blend of material and social technology resulted in a specific object of study: the generalized mind. We will then show that the distribution of precision in experimental psychology outside Leipzig demanded a concerted effort of instruments, texts, and people. It will appear that the forceful attempts to produce precision and uniformity had some rather paradoxical consequences.


Assuntos
Equipamentos e Provisões/história , Ciência de Laboratório Médico/história , Psicologia Experimental/história , Biotecnologia/história , Alemanha , História do Século XX , Estados Unidos
9.
J Exp Med ; 190(6): 749-56, 1999 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-10499913

RESUMO

Although it is well established that immature B lymphocytes are exquisitely sensitive to tolerance induction compared with their mature counterparts, the molecular basis for this difference is unknown. We demonstrate that signaling by B cell antigen receptors leads to distinct and mutually exclusive biologic responses in mature and immature B cells: upregulation of CD86, CD69, and MHC class II in mature cells and receptor editing in immature cells. These responses can be induced simply by elevation of intracellular free calcium levels, as occurs after receptor aggregation. Importantly, induction of immature B cell responses requires much smaller increases in intracellular free calcium than does induction of mature B cell responses. These differences in biologic response and sensitivity to intracellular free calcium likely contributes to selective elimination at the immature stage of even those B cells that express low affinity for self-antigens.


Assuntos
Linfócitos B/imunologia , Regulação da Expressão Gênica/imunologia , Receptores de Antígenos de Linfócitos B/genética , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos B/citologia , Antígeno B7-2 , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Lectinas Tipo C , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Transgênicos , Edição de RNA/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Regulação para Cima
10.
Curr Opin Immunol ; 11(2): 143-51, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10322153

RESUMO

Constitutive signal transduction by B cell antigen-receptors and/or their surrogates appears to be critical for progression through multiple developmental checkpoints and for survival of mature B cells in the periphery. Antigen-induced signaling via the B cell receptor can compensate for defects in constitutive signaling and initiates receptor editing, apoptosis and anergy in normal mice - purging the repertoire of autoreactive cells. Thus development and survival of mature B cells seem to require continuous receptor signaling of a defined amplitude.


Assuntos
Linfócitos B/fisiologia , Receptores de Antígenos de Linfócitos B/fisiologia , Transdução de Sinais , Animais , Antígenos CD/fisiologia , Antígenos CD79 , Precursores Enzimáticos/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas Tirosina Quinases/fisiologia , Quinase Syk , Quinases da Família src/fisiologia
11.
Eur J Appl Physiol Occup Physiol ; 77(6): 523-6, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9650737

RESUMO

We investigated the mechanisms of stress-induced alterations in adrenocorticotrophin (ACTH) release. Tandem parachutists received either a placebo or the beta-adrenoceptor antagonist propranolol prior to a first time parachute jump. Blood samples were drawn 4 h before, immediately after, and 1 h after the jump. Cortisol and catecholamine concentrations displayed a significant stress-induced increase in both groups. The ACTH plasma concentrations significantly increased in the placebo and the propranolol group, with significantly more pronounced changes in the propranolol-treated subjects compared to the placebo group. These data demonstrated a stress-induced increase of ACTH plasma concentrations in humans that was enhanced by beta-blockade.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Hormônio Adrenocorticotrópico/metabolismo , Propranolol/farmacologia , Estresse Psicológico/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Método Duplo-Cego , Epinefrina/sangue , Humanos , Hidrocortisona/sangue , Masculino , Norepinefrina/sangue , Estresse Psicológico/sangue
12.
Psychosom Med ; 60(3): 290-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9625216

RESUMO

OBJECTIVE: To describe the relationships between cardiovascular and natural killer (NK) cell number changes on acute psychological stress in women. METHOD: Data from eight different studies were analyzed. A total of 128 healthy female subjects, 85 younger (18-45 years) and 43 older (49-87 years), had been subjected to a speech stressor (N = 80) or a mental effort stressor (N = 48), mental arithmetic, or the Stroop test. Correlations between changes in NK cell numbers, systolic (SBP) and diastolic (DBP) blood pressure, and heart rate (HR) were computed. Meta-analysis programs were used to study correlations across studies and to examine whether correlations differed with stressors or age. RESULTS: In all studies, significant increases over baseline were observed for each variable. Across studies, the mean weighted r between changes in HR, DBP, and SBP was medium (rw = .25) to large (rw = .64). A medium to large average correlation between HR and NK changes (rw = .37) was observed, whereas average correlations of changes in NK cell numbers with blood pressure changes were small to medium (rw < or = .23). Correlations between changes in NK cell numbers and cardiovascular variables were homogeneous across studies, whereas mutual correlations between cardiovascular variables were heterogeneous. One moderator variable showed itself: correlations between HR and DBP reactions were larger in studies with older than younger subjects. CONCLUSION: NK cell changes and HR responses induced by acute stress in women are regulated, to some extent, by the same mechanisms. Neither the type of stressor nor age seem to be very important when considering correlations between NK cell and cardiovascular changes. This study integrates information about NK cell and cardiovascular responses in women that can be used as reference material in future studies.


Assuntos
Envelhecimento/fisiologia , Nível de Alerta/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Células Matadoras Naturais/imunologia , Estresse Psicológico/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psiconeuroimunologia , Valores de Referência , Estresse Psicológico/imunologia
13.
Psychosom Med ; 60(3): 359-61, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9625225

RESUMO

OBJECTIVE: Although stressor uncontrollability has been shown to suppress immune responses in animals and for human subjects, the results have been inconsistent. We reanalyzed results of our previous study regarding stress-related immune deviation in man, to establish whether perceived uncontrollability of an acute stressor acts as a co-determinant in the observed changes in immunological parameters. METHOD: Three types of cognitive reactions to an acute interpersonal stressor were assessed: "motivation," "uncontrollability," and "guiltiness." Stress-induced changes in the number of several types of immune cells in peripheral blood and proliferative responses of lymphocytes to antigens and mitogens were assessed. RESULTS: In comparison with control subjects and with subjects perceiving high control over the experimental stress situation, the subject perceiving low control showed a stressor-induced decrease in the number of T helper cells. Reversely, subjects perceiving high control showed an increase in the number of B cells as opposed to the other two groups. The effects of perceived uncontrollability could not be accounted for by mood changes, but they were related to previously experienced life stress. CONCLUSIONS: Perceived uncontrollability of an acute stressor can have immuno-modulating effects over and above those of the stressor per se.


Assuntos
Formação de Anticorpos/imunologia , Nível de Alerta/fisiologia , Controle Interno-Externo , Ativação Linfocitária/imunologia , Estresse Psicológico/complicações , Adulto , Culpa , Humanos , Tolerância Imunológica/imunologia , Relações Interpessoais , Acontecimentos que Mudam a Vida , Contagem de Linfócitos , Subpopulações de Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Motivação , Psiconeuroimunologia
14.
J Endocrinol Invest ; 21(3): 148-53, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9591209

RESUMO

Acute psychological stress of a first time parachute jump stimulated DHEA and cortisol secretion in healthy volunteers. A significant shift from cortisol to DHEA occurred during this stress exposure. This effect was more pronounced in subjects receiving the beta-adrenoceptor antagonist propranolol prior to the jump. In contrast, infusion of epinephrine (0.10 microgram/kg/min) or norepinephrine (0.15 microgram/kg/min) for 20 min neither affected DHEA plasma levels nor the DHEA/cortisol ratio. However, pretreatment with propranolol resulted in a significant increase of the DHEA/cortisol ratio upon infusion of the beta-adrenoceptor agonist epinephrine. These data demonstrate that during acute psychological stress stimulation of adrenal steroid release is accompanied by a shift towards DHEA. Augmentation of this effect by beta-adrenoceptor blockade indicates a beta-adrenoceptor-dependent mechanism affecting DHEA release.


Assuntos
Desidroepiandrosterona/sangue , Glândulas Endócrinas/metabolismo , Estresse Psicológico/metabolismo , Doença Aguda , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Catecolaminas/farmacologia , Hormônios/sangue , Humanos , Masculino , Propranolol/farmacologia
15.
Cell ; 92(2): 173-82, 1998 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-9458042

RESUMO

B lymphocyte development is a highly ordered process that involves immunoglobulin gene rearrangements, antigen receptor expression, and a learning process that minimizes the development of cells with reactivity to self tissue. Two distinct mechanisms for immune tolerance have been defined that operate during early bone marrow stages of B cell development: apoptosis, which eliminates clones of cells, and receptor editing, which spares the cells but genetically reprograms their autoreactive antigen receptors through nested immunoglobulin L chain gene rearrangements. We show here that sensitivity to antigen-induced apoptosis arises relatively late in B cell development and is preceded by a functionally distinct developmental stage capable of receptor editing. This regulation compartmentalizes clonal selection from receptor selection.


Assuntos
Apoptose/imunologia , Linfócitos B/imunologia , Deleção Clonal , Rearranjo Gênico de Cadeia Leve de Linfócito B/imunologia , Tolerância Imunológica/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Sequência de Aminoácidos , Animais , Autoantígenos/imunologia , Células da Medula Óssea , Cálcio/metabolismo , Diferenciação Celular , Células Cultivadas , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/genética , Genes bcl-2/imunologia , Antígenos H-2/análise , Imunoglobulina D/análise , Imunoglobulina M/análise , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , RNA Mensageiro/análise
16.
Sci Context ; 11(1): 23-50, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-11623719

RESUMO

This essay addresses the historiographical question of how to study scientific instruments and the connections between them without rigidly determining the boundaries of the object under historical scrutiny beforehand. To do this, I will explore an episode in the early history of the tachistoscope--defined, among other things, as an instrument for the brief exposure of visual stimuli in experimental psychology. After looking at the tachistoscope described by physiologist Volkmann in 1859, I will turn to the gravity chronometer, constructed by Cattell at Wundt's Leipzig institute of psychology in the 1880s. Taking Wittgenstein's notion of family resemblances as a methodological suggestion to travel from one member to another to find out just how members relate to one another, I will investigate part of the family to which both the trachistoscope and the gravity chronometer turn out to belong. A detailed analysis of these instruments, using both historical sources and historical accounts of psychological instruments, may demonstrate that the instrument is not a standard package that, if well applied, will simply secure good results. Each package needs to be assembled again and again; the particular package that is assembled may differ on different occasions. Thus an alternative is developed to an understanding of instruments as univocally functioning material means.


Assuntos
Equipamentos e Provisões/história , Psicologia Experimental/história , Visão Ocular , História do Século XIX , História do Século XX
17.
J Neuroimmunol ; 74(1-2): 159-64, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9119969

RESUMO

Expression and in-vivo modulation of beta- and alpha-adrenoceptors on peripheral human natural killer (CD16+) cells was investigated. Ligand binding studies revealed that CD16+ lymphocytes express beta2, alpha1-, alpha2- but not beta1-adrenoceptors. Infusion of adrenaline, but not noradrenaline, significantly decreased beta2- and alpha1-adrenoceptor numbers on NK cells. Both catecholamines did not appreciably alter alpha2-adrenoceptor numbers. Additional analyses showed that adrenaline administration increases alpha2-adrenoceptor numbers on peripheral mononuclear blood cells (PBMC) and T-cell subsets (CD4+, CD8+) in contrast to decreased receptor numbers on CD16+ cells. These data demonstrate a specific effect of increasing levels of circulating catecholamines on beta2-adrenoceptors on NK cells.


Assuntos
Células Matadoras Naturais/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos beta/metabolismo , Agonistas Adrenérgicos/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Adulto , Antígenos CD4/análise , Antígenos CD8/análise , Epinefrina/farmacologia , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Masculino , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Norepinefrina/farmacologia , Receptores de IgG/análise , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/metabolismo
18.
Brain Behav Immun ; 11(4): 321-32, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9512818

RESUMO

Natural killer (NK) cell circulation is subject to adrenergic regulation. Exactly how NK cells are released into the circulation is unknown. In an attempt to identify some of the mechanisms, the present report focuses on aspects of adhesion regulation of NK cells. Results demonstrate that interactions between NK and endothelial cells (EC) in vitro can be reduced by beta 2-adrenoceptor stimulation for as long as the receptor stimulation occurs. The level of soluble adhesion molecules (sICAM-1, sE-selectin, sVCAM-1) in vivo remained unchanged during adrenaline infusion. In vitro analyses further reveal the requirement for Ca2+/Mg2+ in NK-EC adhesion. Blocking studies indicate the involvement of several members of the beta 1(CD29)- and beta 2(CD18)-integrin family, reducing NK cell adhesion by 28 to 39%. Stimulation of beta 2-adrenoceptors in the presence of these blocking antibodies further reduced NK adhesion by an average of 22%. Analysis of NK cell adhesion to various extracellular matrix components demonstrates significant NK cell adhesion to fibronectin but much less to laminin or collagens I and IV. NK cell adhesion to fibronectin was reduced by 50% upon beta 2-adrenoceptor stimulation, independent of the VLA-4/VLA-5 binding site on fibronectin. Together these results contribute to understanding the influences of beta-adrenoceptor stimulation on NK cell circulation and adhesion.


Assuntos
Células Matadoras Naturais/fisiologia , Receptores Adrenérgicos beta/fisiologia , Adesão Celular/fisiologia , Comunicação Celular/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Matriz Extracelular/fisiologia , Fibronectinas/fisiologia , Humanos , Cinética
19.
Brain Behav Immun ; 10(2): 77-91, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8811932

RESUMO

Recent studies demonstrate that acute psychological stress in man affects lymphocyte circulation. It has been suggested that catecholamines are responsible for these changes. The present review summarizes findings regarding catecholamine-induced lympho- and leukocytosis, starting with observations dating back to the beginning of this century. Particular attention is given to the mechanisms of this phenomenon and the potential site of origin of newly appearing leukocytes. Characteristically, two phases are recognized after catecholamine administration: a quick (<30 min) mobilization of lymphocytes, followed by an increase in granulocyte numbers with decreasing lymphocyte numbers. Many studies have shown that catecholamines predominantly affect natural killer (NK) cell and granulocyte circulation, whereas T- and B-cell numbers remain relatively unaffected. The changes in lymphocyte circulation seem to be mainly mediated via activation of beta2-adrenoceptors, whereas granulocyte increases involve alpha-adrenoceptor stimulation. Results further indicate that the marginal pool and the spleen are the major sources for freshly recruited lymphocytes, whereas granulocytes are predominantly released from the marginal pool and the lung. Results from acute psychological stress or physical exercise models corroborate the results obtained with catecholamine administration. Together, the data demonstrate that components of the innate immune system participate in the classical fight/flight response.


Assuntos
Epinefrina/farmacologia , Leucocitose/fisiopatologia , Norepinefrina/farmacologia , Estresse Psicológico/fisiopatologia , Doença Aguda , Córtex Suprarrenal/fisiopatologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Emoções , Epinefrina/fisiologia , Feminino , Granulócitos/efeitos dos fármacos , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Contagem de Leucócitos/efeitos dos fármacos , Leucocitose/etiologia , Linfocitose/induzido quimicamente , Linfocitose/fisiopatologia , Tecido Linfoide/imunologia , Tecido Linfoide/fisiopatologia , Masculino , Norepinefrina/fisiologia , Psiconeuroimunologia , Receptores Adrenérgicos beta 2/efeitos dos fármacos , Receptores Adrenérgicos beta 2/fisiologia , Estresse Psicológico/imunologia
20.
FASEB J ; 10(4): 517-24, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8647351

RESUMO

Acute stress evokes immediate responses in the cardiovascular endocrine, and immune systems. In particular, the number and activity of natural killer (NK) lymphocytes increase after stress. Here, we investigate the possibility to pharmacologically interfere with these stress-induced immunologic changes. Twenty-five healthy males were subjected to an acute stressor, a first-time tandem parachute jump. Subjects were randomly assigned to a beta-adrenoceptor antagonist (propranolol), a benzodiazepine (alprazolam), or placebo group. To analyze the role of the spleen in lymphocyte redistribution, splenectomized subjects performed a parachute jump. Propranolol, but no alprazolam, inhibited the heart rate increase during jumping. Increases in epinephrine and cortisol in the propranolol group were comparable to placebo, but were attenuated by alprazolam. The number and activity of NK cells significantly increased in the placebo group but not in the propranolol group immediately after stress. Alprazolam treatment did not alter the increase in NK cell numbers but did inhibit the increase in NK activity. In splenectomized subjects, NK cell numbers, but not NK activity, increased as in placebo subjects. We conclude that stress-induced changes in the immune system are controlled by beta-adrenergic mechanisms and only partly depend on the spleen; central interference with alprazolam differentially affects stress-induced changes in the NK cell compartment.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Alprazolam/farmacologia , Ansiolíticos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Propranolol/farmacologia , Estresse Psicológico/imunologia , Adulto , Linhagem Celular , Humanos , Hidrocortisona/sangue , Células Matadoras Naturais/imunologia , Masculino , Esplenectomia
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