Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 110(8): 2981-6, 2013 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-23382225

RESUMEN

Recent work has suggested that beta-lactam antibiotics might directly affect eukaryotic cellular functions. Here, we studied the effects of commonly used beta-lactam antibiotics on rodent and human T cells in vitro and in vivo on T-cell-mediated experimental autoimmune diseases. We now report that experimental autoimmune encephalomyelitis and adjuvant arthritis were significantly more severe in rats treated with cefuroxime and other beta-lactams. T cells appeared to mediate the effect: an anti-myelin basic protein T-cell line treated with cefuroxime or penicillin was more encephalitogenic in adoptive transfer experiments. The beta-lactam ampicillin, in contrast to cefuroxime and penicillin, did not enhance encephalomyelitis, but did inhibit the autoimmune diabetes developing spontaneously in nonobese diabetic mice. Gene expression analysis of human peripheral blood T cells showed that numerous genes associated with T helper 2 (Th2) and T regulatory (Treg) differentiation were down-regulated in T cells stimulated in the presence of cefuroxime; these genes were up-regulated in the presence of ampicillin. The T-cell protein that covalently bound beta-lactam antibiotics was found to be albumin. Human and rodent T cells expressed albumin mRNA and protein, and penicillin-modified albumin was taken up by rat T cells, leading to enhanced encephalitogenicity. Thus, beta-lactam antibiotics in wide clinical use have marked effects on T-cell behavior; beta-lactam antibiotics can function as immunomodulators, apparently through covalent binding to albumin.


Asunto(s)
Albúminas/metabolismo , Antibacterianos/farmacología , Expresión Génica/efectos de los fármacos , Linfocitos T/efectos de los fármacos , beta-Lactamas/farmacología , Animales , Antibacterianos/metabolismo , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/inmunología , Humanos , Unión Proteica , Ratas , Linfocitos T/inmunología , Linfocitos T/metabolismo , beta-Lactamas/metabolismo
2.
Stem Cell Rev Rep ; 8(2): 343-54, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21881833

RESUMEN

In human multiple myeloma (MM), the tumor cells exhibit strict dependence on bone marrow (BM) stromal elements. It has been suggested that, in turn, MM cells modify multipotent stromal cells (MSCs), diverting them to support the myeloma. We investigated MM-derived MSCs by comparing their toll-like receptor (TLR) responses to those of MSCs derived from healthy controls. We now report that MM-derived MSCs manifested intact proliferation responses and IL-6 secretion and their adipose and osteogenic differentiation responses to TLR ligands were also similar to those of healthy controls, ranging from augmentation to inhibition. However, MM-derived MSCs were found to be defective in IL-8 secretion and ERK1/2 phosphorylation following TLR-2 activation. Moreover, MM-derived MSCs failed to respond to EGF by elevation of ERK1/2 phosphorylation. The persistence of these changes in extensively cultured MM-derived MSCs, suggests that these cells are stably, if not irreversibly modified.


Asunto(s)
Factor de Crecimiento Epidérmico/farmacología , Células Madre Mesenquimatosas/patología , Mieloma Múltiple/inmunología , Mieloma Múltiple/patología , Receptores Toll-Like/metabolismo , Adulto , Biomarcadores/metabolismo , Diferenciación Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Interleucina-8/metabolismo , Cinética , Ligandos , Lipoproteínas/farmacología , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/enzimología , Persona de Mediana Edad , Fosforilación/efectos de los fármacos
3.
J Immunol ; 187(10): 5452-62, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21998458

RESUMEN

Gliomas that grow uninhibited in the brain almost never metastasize outside the CNS. The rare occurrences of extracranial metastasis are usually associated with a suppressed immune system. This observation raises the possibility that some gliomas might not grow outside the CNS due to an inherent immune response, We report in this study that the highly malignant F98 Fischer rat undifferentiated glioma, which grows aggressively in the brain, spontaneously regresses when injected live s.c. We found that this regression is immune-mediated and that it markedly enhances the survival or cures rats challenged with the same tumor intracranially either before or after the s.c. live-cell treatment. Adoptive transfer experiments showed the effect was immune-mediated and that the CD8 T cell fraction, which exhibited direct tumor cytotoxicity, was more effective than the CD4 T cell fraction in mediating resistance to intracranial challenge of naive rats. Brain tumors from treated rats exhibited enhanced CD3(+)CD8(+)CD4(-) and CD3(+)CD4(+)CD8(-) T cell infiltration and IFN-γ secretion. The results in the F98 glioma were corroborated in the Lewis rat CNS-1 astrocytoma. In both tumor models, s.c. treatment with live cells was significantly better than immunization with irradiated cells. We propose in this study a location-based immunotherapeutic phenomenon we term "split immunity": a tumor that thrives in an immune-privileged site may be inhibited by injecting live, unmodified tumor cells into a site that is not privileged, generating protective immunity that spreads back to the privileged site. Split immunity could explain several long-standing paradoxes regarding the lack of overt extracranial metastasis in patients with primary brain tumors.


Asunto(s)
Astrocitoma/inmunología , Astrocitoma/prevención & control , Diferenciación Celular/inmunología , Glioma/inmunología , Glioma/prevención & control , Rechazo de Injerto/inmunología , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/prevención & control , Animales , Astrocitoma/patología , Supervivencia Celular/inmunología , Células Cultivadas , Células Clonales , Técnicas de Cocultivo , Relación Dosis-Respuesta Inmunológica , Femenino , Glioma/patología , Rechazo de Injerto/patología , Inyecciones Intraventriculares , Inyecciones Subcutáneas , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Neoplasias Cutáneas/patología , Células Tumorales Cultivadas
4.
J Autoimmun ; 35(2): 135-44, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20580204

RESUMEN

T cell vaccination (TCV) with irradiated encephalitogenic T cells induces resistance to EAE. However, the fate of the encephalitogenic T cells in vivo following TCV has yet to be studied. Here we used anti-MBP encephalitogenic T cells that were transduced to express GFP to study the effects of TCV on these cells. In naïve rats or in control-vaccinated (Ova-GFP) rats injected i.v. with GFP-labeled effector cells, high numbers of effector T cells were found along with macrophages, CD8 T cells and Non-GFP CD4 cells in the spleens, parathymic lymph nodes (PTLN) and spinal cords. In contrast, the recipients that had been treated with TCV (anti-MBP T-cell lines) showed few if any GFP-labeled effector T cells throughout the disease (day 1-8) and their spinal cords were almost clear of macrophages, CD4 and CD8 cells. Splenocytes in the control groups secreted IFNgamma in response to MBP and showed high numbers of IFNgamma secreting CD4 and CD8 cells in their spinal cords at the disease peak. In the TCV-protected groups, splenocytes showed no reactivity to MBP but secreted IFNgamma in response to irradiated encephalitogenic T cells--an anti-idiotypic response. Thus, TCV leads to a marked decrease in the numbers of effector T cells in the CNS and lymphoid organs, to a marked reduction in the Th1 cytokine producing cells in the CNS, and to the appearance of T cells responsive to the anti-MBP effector T cells.


Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Esclerosis Múltiple/inmunología , Proteína Básica de Mielina/metabolismo , Linfocitos T/metabolismo , Animales , Antígenos CD4/biosíntesis , Antígenos CD8/biosíntesis , Línea Celular , Encefalomielitis Autoinmune Experimental/prevención & control , Femenino , Proteínas Fluorescentes Verdes/genética , Humanos , Interferón gamma/metabolismo , Activación de Linfocitos , Macrófagos/patología , Proteína Básica de Mielina/inmunología , Ratas , Ratas Endogámicas Lew , Médula Espinal/patología , Linfocitos T/inmunología , Linfocitos T/patología , Linfocitos T/trasplante , Vacunación
5.
Immunology ; 128(1): 92-102, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19689739

RESUMEN

Fischer strain rats resist active induction of experimental autoimmune encephalomyelitis (EAE) following immunization with guinea-pig myelin basic protein (MBP) in complete Freund's adjuvant (CFA). Nevertheless, we now report that an encephalitogenic CD4(+) anti-MBP T-cell line could be developed from actively immunized Fischer rats. Adoptive transfer of the activated line mediated acute EAE in adult Fischer rats, but not in 1-day-old rats. Moreover, we found that both resting and activated anti-MBP T cells injected 1 day post-natally rendered these rats susceptible later in life to the active induction of EAE by immunization with MBP/CFA. The actively induced EAE manifested the accelerated onset of a secondary, memory-type response. Resting anti-MBP T cells injected even up to 2 weeks post-natally produced no clinical signs but seeded 50-100% of the recipients for an active encephalitogenic immune response to MBP. An earlier T-cell injection (1-2 days) produced a higher incidence and stronger response. The transferred resting T cells entered the neonatal spleen and thymus and proliferated there but did not change the total anti-MBP precursor number in adults. Splenocytes harvested from rats that were injected neonatally but not exposed to MBP in vivo proliferated strongly and produced significant amounts of interferon-gamma to MBP in vitro. Similar results were observed in rats injected with resting T-cell lines reactive to ovalbumin, suggesting that the neonatal injection of resting T cells specific for a self or for a foreign antigen can seed the immune system with the potential for an enhanced effector response to that antigen later in life.


Asunto(s)
Linfocitos T CD4-Positivos/trasplante , Encefalomielitis Autoinmune Experimental/inmunología , Proteína Básica de Mielina/inmunología , Traslado Adoptivo , Animales , Animales Recién Nacidos , Linfocitos T CD4-Positivos/inmunología , Línea Celular , Proliferación Celular , Susceptibilidad a Enfermedades , Activación de Linfocitos/inmunología , Ovalbúmina/inmunología , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Bazo/inmunología , Timo/inmunología
6.
J Neuroimmunol ; 208(1-2): 19-29, 2009 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-19189872

RESUMEN

Accumulating evidence suggests that autoimmunity against neuronal proteins is important for MS pathogenesis. We have characterized T- and B-cell responses associated with experimental autoimmune encephalomyelitis (EAE) induced in Lewis rats with recombinant beta-Synuclein (betaSync), a neuronal component. The encephalitogenic betaSync-specific T cells recognize a single immunodominant region with an epitope delineated at amino acids 97-105; B-cell specificity is more widespread, albeit directed mostly to the C-terminus of betaSync. Most interestingly, betaSync-induced autoimmune T- and B-cell responses spread not only to other neuronal antigens but also to myelin encephalitogens, raising the possibility that anti-neuronal immune attacks could also result in demyelination.


Asunto(s)
Autoanticuerpos/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Vaina de Mielina/inmunología , Vaina de Mielina/metabolismo , Sinucleína beta/fisiología , Secuencia de Aminoácidos , Animales , Autoanticuerpos/biosíntesis , Línea Celular , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/genética , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/metabolismo , Femenino , Humanos , Ratones , Datos de Secuencia Molecular , Ratas , Ratas Endogámicas Lew , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/toxicidad , Sinucleína beta/toxicidad
7.
PLoS One ; 3(12): e4026, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19107191

RESUMEN

The 60 kDa heat shock protein (HSP60) has been reported to influence T-cell responses in two ways: as a ligand of toll-like receptor 2 signalling and as an antigen. Here we describe a new mechanism of T-cell immuno-regulation focused on HSP60: HSP60 is up-regulated and presented by activated T cells (HSP60 is an ergotope) to regulatory (anti-ergotypic) T cells. Presentation of HSP60 by activated T cells was found to be MHC-restricted and dependent on accessory molecules - CD28, CD80 and CD86. Anti-ergotypic T cells responded to T-cell HSP60 by proliferation and secreted IFNgamma and TGFbeta1. In vitro, the anti-ergotypic T cells inhibited IFNgamma production by their activated T-cell targets. In vivo, adoptive transfer of an anti-ergotypic HSP60-specific T-cell line led to decreased secretion of IFNgamma by arthritogenic T cells and ameliorated adjuvant arthritis (AA). Thus, the presentation of HSP60 by activated T cells turns them into targets for anti-ergotypic regulatory T cells specific for HSP60. However, the direct interaction between the anti-ergotypic T regulators (anti-HSP60) and the activated T cells also down-regulated the regulators. Thus, by functioning as an ergotope, HSP60 can control both the effector T cells and the regulatory HSP60-specific T cells that control them.


Asunto(s)
Chaperonina 60/inmunología , Epítopos de Linfocito T/inmunología , Linfocitos T Reguladores/inmunología , Animales , Autoantígenos/inmunología , Enfermedades Autoinmunes/inmunología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Chaperonina 60/química , Chaperonina 60/metabolismo , Chaperonina 60/fisiología , Femenino , Inmunidad Celular/efectos de los fármacos , Inflamación/inmunología , Interferón gamma/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/farmacología , Ratas , Ratas Endogámicas Lew , Linfocitos T Reguladores/metabolismo , Vacunas de ADN/farmacología
8.
Arch Immunol Ther Exp (Warsz) ; 55(1): 13-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17221336

RESUMEN

Current treatment of human autoimmune diseases (AIDs) was developed empirically and relies mostly on non-selective suppression of the immune system. Traditional non-selective immunosuppressants such as corticosteroids, cyclophosphamide, and methotrexate and more novel means such as monoclonal antibodies to CD3, CD4, or CD25 do not discriminate between pathogenic and beneficial T cells. Importantly, the severe side effects seen with current therapies are related to the fact that these treatments not only suppress the pathogenic disease-inducing cells, but also cells influential in combating infections and killing malignant cells. Severe infections and malignancies are the inevitable result of non-selective immune suppression. Many of the novel forms of therapy of AID were developed in experimental animals, and their translation to the human disease was associated with the revelation of unexpected and sometimes catastrophic side effects. These surprises underscore the major differences between the relative simplicity of the experimental model and the complexity of the human disease. How can this current state of treatment of AID be improved? Which principles should guide us in the design of new treatments? This review attempts to offer a new look at these questions.


Asunto(s)
Alergia e Inmunología/tendencias , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Medicina Interna/tendencias , Animales , Enfermedades Autoinmunes/tratamiento farmacológico , Modelos Animales de Enfermedad , Predicción , Humanos
9.
Expert Rev Neurother ; 6(5): 653-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16734513

RESUMEN

Alzheimer's disease (AD) is a common and devastating neurodegenerative disease. The incidence of AD is increasing in Western societies. The current treatment of AD is mostly symptomatic and ineffective in stopping or reversing the cognitive impairment. One of the exciting and effective new treatments developed in experimental AD is immunization against amyloid-beta peptide. This article provides an overview of immunization therapy in AD and examines the future prospects of this therapeutic modality.


Asunto(s)
Enfermedad de Alzheimer/terapia , Inmunoterapia , Enfermedad de Alzheimer/inmunología , Péptidos beta-Amiloides/inmunología , Animales , Enfermedades Autoinmunes/etiología , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Humanos , Inmunoterapia/efectos adversos , Inmunoterapia/métodos , Inmunoterapia/tendencias
10.
J Neuroimmunol ; 174(1-2): 3-11, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16427143

RESUMEN

Recent work has shown neuro-protective effects of immunization with self-CNS antigens in animal models of Alzheimer's disease, prion diseases and CNS trauma. The major concern with such an approach is the inadvertent induction of autoimmune disease. The present work was initiated to study the incidence of autoimmune disease associated with the induction of T cell autoimmunity to a panel of 70 peptides derived from CNS proteins. Using a MHC class II motif developed in our laboratory to identify candidate peptides, we selected 70 peptides from 40 different CNS proteins. The proteins were selected randomly and represented various biological functions (surface receptors, structural proteins, synaptic proteins, neurodegeneration related proteins). Each peptide was emulsified in CFA and injected to autoimmune-prone Lewis rats. Immunogenicity was verified by peptide-specific LN cell proliferation. In addition, T cell lines were generated for many peptides and tested by adoptive transfer. Except for the previously reported pathogenicity of beta-synuclein, none of the 68 peptides from 39 proteins was found to induce CNS disease in recipient rats. These findings underscore the efficiency of immunological regulation in preventing CNS autoimmune disease, and confirm the uniqueness of the well-known pathogenic CNS auto-antigens.


Asunto(s)
Autoantígenos/fisiología , Enfermedades Autoinmunes del Sistema Nervioso/etiología , Sistema Nervioso Central/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Secuencia de Aminoácidos , Animales , Presentación de Antígeno , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Proliferación Celular , Sistema Nervioso Central/patología , Células Clonales , Citocinas/metabolismo , Relación Dosis-Respuesta Inmunológica , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Inmunización/métodos , Ratones , Ratones Endogámicos NOD , Ratas , Ratas Endogámicas Lew , Especificidad del Receptor de Antígeno de Linfocitos T/inmunología , Especificidad del Receptor de Antígeno de Linfocitos T/fisiología
11.
J Immunol ; 175(6): 3594-602, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16148103

RESUMEN

We recently reported that soluble 60-kDa heat shock protein (HSP60) can directly activate T cells via TLR2 signaling to enhance their Th2 response. In this study we investigated whether HSP60 might also activate B cells by an innate signaling pathway. We found that human HSP60 (but not the Escherichia coli GroEL or the Mycobacterial HSP65 molecules) induced naive mouse B cells to proliferate and to secrete IL-10 and IL-6. In addition, the HSP60-treated B cells up-regulated their expression of MHC class II and accessory molecules CD69, CD40, and B7-2. We tested the functional ability of HSP60-treated B cells to activate an allogeneic T cell response and found enhanced secretion of both IL-10 and IFN-gamma by the responding T cells. The effects of HSP60 were found to be largely dependent on TLR4 and MyD88 signaling; B cells from TLR4-mutant mice or from MyD88 knockout mice showed decreased responses to HSP60. Care was taken to rule out contamination of the HSP60 with LPS as a causative factor. These findings add B cells to the complex web of interactions by which HSP60 can regulate immune responses.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antígenos de Diferenciación/metabolismo , Linfocitos B/inmunología , Chaperonina 60/inmunología , Activación de Linfocitos/inmunología , Receptores Inmunológicos/metabolismo , Receptor Toll-Like 4/metabolismo , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Animales , Proliferación Celular , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Interleucinas/metabolismo , Ratones , Ratones Endogámicos , Ratones Noqueados , Factor 88 de Diferenciación Mieloide , Receptores Inmunológicos/deficiencia , Transducción de Señal/inmunología , Receptor Toll-Like 4/deficiencia , Regulación hacia Arriba/genética
12.
J Immunol ; 175(5): 3439-45, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16116239

RESUMEN

Alzheimer's disease (AD) is the most common human neurodegenerative disease, leading to progressive cognitive decline and eventually death. The prevailing paradigm on the pathogenesis of AD is that abnormally folded proteins accumulate in specific brain areas and lead to neuronal loss via apoptosis. In recent years it has become evident that an inflammatory and possibly autoimmune component exists in AD. Moreover, recent data demonstrate that immunization with amyloid-beta peptide is therapeutically effective in AD. The nature of CNS Ags that are the target of immune attack in AD is unknown. To identify potential autoantigens in AD, we tested sera IgG Abs of AD patients in immunoblots against brain and other tissue lysates. We identified a 42-kDa band in brain lysates that was detected with >50% of 45 AD sera. The band was identified by mass spectrometry to be aldolase A. Western blotting with aldolase using patient sera demonstrated a band of identical size. The Ab reactivity was verified with ELISAs using aldolase. One of 25 elderly control patients and 3 of 30 multiple sclerosis patients showed similar reactivity (p < 0.002). In enzymatic assays, anti-aldolase positive sera were found to inhibit the enzyme's activity, and the presence of the substrate (fructose 1,6-diphosphate) enhanced Ab binding. Immunization of rats and mice with aldolase in complete Freund's adjuvant was not pathogenic. These findings reveal an autoimmune component in AD, point at aldolase as a common autoantigen in this disease, and suggest a new target for potential immune modulation.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Autoantígenos/sangre , Fructosa-Bifosfato Aldolasa/inmunología , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/inmunología , Secuencia de Aminoácidos , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Fructosa-Bifosfato Aldolasa/sangre , Humanos , Sueros Inmunes/inmunología , Inmunización , Inmunoglobulina G/inmunología , Datos de Secuencia Molecular , Peso Molecular , Ratas , Ratas Endogámicas Lew
13.
J Autoimmun ; 24(3): 191-201, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15848041

RESUMEN

T regulatory cells play an important role in regulating T cell responses. Anti-ergotypic T cells are a subset of regulatory T cells that proliferate in response to activation markers, ergotopes, expressed on activated, and not on resting syngeneic T cells. Here we report the presence of anti-ergotypic T cells in lymph nodes, spleens and thymuses of naive rats. The development of anti-ergotypic T cells appeared to be independent of antigen priming, as thymocytes from one-day old rats exhibited significant anti-ergotypic proliferative responses. The anti-ergotypic T cells were found to be of the CD8+ phenotype, and included both TCRalpha/beta+ and TCRgamma/delta+ T cells. The TCRgamma/delta+ anti-ergotypic T cells secreted IFNgamma and TNFalpha in response to activated T cells; the TCRalpha/beta+ T cells proliferated but did not secret detectable cytokines. We found that the interaction between the anti-ergotypic T cells and stimulator T cells required cell-to-cell contact between the T cells. Professional APCs were not needed. The response of the TCRalpha/beta+CD8+ anti-ergotypic T cells was MHC-I restricted and B7-CD28 dependent; the response of the TCRgamma/delta+ anti-ergotypic T cells was B7-CD28 dependent, but was not inhibited by antibodies to classical MHC-I or MHC-II molecules. The existence of anti-ergotypic T cells in naive animals suggests that these cells might have a role in the regulation and maintenance of the immune system.


Asunto(s)
Autoinmunidad , Epítopos de Linfocito T/inmunología , Activación de Linfocitos/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Antígenos de Diferenciación/inmunología , Femenino , Interferón gamma/inmunología , Ratas , Ratas Endogámicas Lew , Factor de Necrosis Tumoral alfa/inmunología
14.
Arthritis Rheum ; 50(11): 3712-20, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15529360

RESUMEN

OBJECTIVE: Adjuvant arthritis can be induced in Lewis rats by immunization with Mycobacterium tuberculosis (Mt). The mycobacterial 65-kd heat-shock protein (Hsp65) is targeted by arthritogenic T cells. However, Hsp65 and the mycobacterial 71-kd heat-shock protein are also recognized by T cells that can down-regulate adjuvant-induced arthritis (AIA). We have recently demonstrated that vaccination with human Hsp60 DNA inhibits AIA. The present study was undertaken to analyze the role of the T cell responses to self HSP molecules other than Hsp60 in the control of AIA. METHODS: Lewis rats were immunized with DNA vaccines coding for human Hsp70 or Hsp90 (Hsp70 plasmid [pHsp70] or pHsp90), and AIA was induced. The T cell response to Mt, Hsp60, Hsp70, and Hsp90 (proliferation and cytokine release) was studied, and the T cell response to Hsp60 was mapped with overlapping peptides. RESULTS: The Hsp70 or Hsp90 DNA vaccines shifted the arthritogenic T cell response from a Th1 to a Th2/3 phenotype and inhibited AIA. We detected immune crosstalk between Hsp70/90 and Hsp60: both the Hsp70 and Hsp90 DNA vaccines induced Hsp60-specific T cell responses. Similarly, DNA vaccination with Hsp60 induced Hsp70-specific T cell immunity. Epitope mapping studies revealed that Hsp60-specific T cells induced by pHsp70 vaccination reacted with known regulatory Hsp60 epitopes. CONCLUSION: T cell immunity to Hsp70 and to Hsp90, like Hsp60-specific immunity, can modulate the arthritogenic response in AIA. In addition, our results suggest that the regulatory mechanisms induced by Hsp60, Hsp70, and Hsp90 are reinforced by an immune network that connects their reactivities.


Asunto(s)
Artritis Experimental/prevención & control , Chaperonina 60/inmunología , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/genética , Vacunación , Vacunas de ADN/uso terapéutico , Animales , Formación de Anticuerpos , Antígenos Bacterianos/inmunología , Artritis Experimental/inmunología , Proteínas Bacterianas/inmunología , Chaperoninas/inmunología , Reacciones Cruzadas , Epítopos , Femenino , Proteínas HSP70 de Choque Térmico/inmunología , Proteínas HSP90 de Choque Térmico/inmunología , Humanos , Ratas , Ratas Endogámicas Lew , Linfocitos T/inmunología
15.
J Nutr ; 134(8): 1964-9, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15284384

RESUMEN

Probiotic bacteria have beneficial effects in infectious and inflammatory diseases, principally in bowel disorders. In the case of chronic progressive autoimmune arthritides, a major goal of treatment is to reduce inflammation. We hypothesized that probiotic bacteria would ameliorate inflammation found in arthritis models. To assess this effect, Lewis rats were injected with 50 microg bovine alpha-tropomyosin (TRM) or complete Freund's adjuvant (CFA) to induce tropomyosin arthritis (TA) or adjuvant arthritis (AA), respectively. In both models, the rats were divided into 6 groups and fed 0.5 mL/d of the following suspensions: 1) heat-killed Lactobacillus GG (LGG) bacteria; 2) live LGG, both 10(11) colony-forming units (cfu)/L; 3) sterilized milk; 4) plain yogurt; 5) yogurt containing 10(11) cfu/L LGG; or 6) sterilized water. In the disease-prevention experiments, feeding started 1 wk before or after disease induction. In the therapeutic experiments, feeding was initiated at the onset of clinical arthritis. In all experiments, there were significant interactions between time and treatment (P < 0.001), except for milk, which had no effect in the therapeutic experiment. Histologically, rats fed yogurt containing LGG had a milder inflammation in all experiments (P < 0.05), whereas rats fed plain yogurt exhibited a moderate inflammatory score only in the prevention experiments. Anti-TRM antibody titers were not affected by any of the treatments in any of the experiments. Ingestion of live or heat-killed human LGG had a clinically beneficial effect on experimental arthritis. Our observation of the remarkable preventive and curative effect on arthritis using commercial yogurts containing lactobacilli, especially LGG, suggests the need for investigation of these agents in arthritic patients.


Asunto(s)
Artritis Experimental/terapia , Lactobacillus , Probióticos/uso terapéutico , Administración Oral , Animales , Artritis Experimental/clasificación , Artritis Experimental/patología , Femenino , Ratas , Ratas Endogámicas Lew , Índice de Severidad de la Enfermedad
16.
J Clin Invest ; 113(6): 924-32, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15067325

RESUMEN

Ab's to the alpha-chain of the IL-2 receptor (anti-CD25) are used clinically to achieve immunosuppression. Here we investigated the effects of DNA vaccination with the whole CD25 gene on the induction of rat adjuvant arthritis. The DNA vaccine protected the rats and led to a shift in the cytokine profile of T cells responding to disease target antigens from Th1 to Th2. The mechanism of protection was found to involve the induction of an antiergotypic response, rather than the induction of anti-CD25 Ab's. Antiergotypic T cells respond to activation molecules, ergotopes, expressed on syngeneic activated, but not resting, T cells. CD25-derived peptides function as ergotopes that can be recognized by the antiergotypic T cells. Antiergotypic T cells taken from control sick rats did not proliferate against activated T cells and secreted mainly IFN-gamma. In contrast, antiergotypic cells from CD25-DNA-protected rats proliferated against activated T cells and secreted mainly IL-10. Protective antiergotypic T cells were found in both the CD4+ and CD8+ populations and expressed alpha/beta or gamma/delta T cell receptors. Antiergotypic alpha/beta T cells were MHC restricted, while gamma/delta T cells were MHC independent. Thus, CD25 DNA vaccination may induce protection from autoimmunity by inducing a cytokine shift in both the antiergotypic response and the response to the antigens targeted in the disease.


Asunto(s)
Artritis Experimental/prevención & control , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/inmunología , Vacunas de ADN/inmunología , Animales , Antígenos/efectos de los fármacos , Antígenos/inmunología , Artritis Experimental/inmunología , División Celular/efectos de los fármacos , Citocinas/efectos de los fármacos , Regulación hacia Abajo , Femenino , Ratas , Ratas Endogámicas Lew , Linfocitos T/efectos de los fármacos , Vacunas de ADN/farmacología
17.
J Immunol ; 172(7): 4618-23, 2004 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15034080

RESUMEN

Vascular endothelial growth factor (VEGF) and its receptors are critical in angiogenesis. The main player in the secretion and response to VEGF is the endothelial cell. We initiated this study to test whether T cells can secrete VEGF and are able to respond to it. Here we show that VEGF is secreted by T cells on stimulation by specific Ag or by IL-2 and by hypoxia; thus, activated T cells might enhance angiogenesis. Hypoxia also induced the expression in T cells of VEGFR2, suggesting that T cells might also respond to VEGF. Indeed, VEGF augmented IFN-gamma and inhibited IL-10 secretion by T cells responding to mitogen or Ag; thus, VEGF can enhance a Th1 phenotype. Encephalitogenic T cells stimulated in the presence of VEGF caused more severe and prolonged encephalomyelitis. Thus, T cells can play a role in angiogenesis by delivering VEGF to inflammatory sites, and VEGF can augment proinflammatory T cell differentiation.


Asunto(s)
Citocinas/biosíntesis , Activación de Linfocitos , Neovascularización Patológica/inmunología , Neovascularización Patológica/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células TH1/inmunología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adyuvantes Inmunológicos/metabolismo , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/fisiología , Animales , Diferenciación Celular/inmunología , Línea Celular , Células Clonales , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Hipoxia/metabolismo , Inflamación/inmunología , Inflamación/patología , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/farmacología , Mediadores de Inflamación/fisiología , Interleucina-2/fisiología , ARN Mensajero/biosíntesis , Ratas , Ratas Endogámicas Lew , Subgrupos de Linfocitos T/citología , Células TH1/citología , Células TH1/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Factor A de Crecimiento Endotelial Vascular/farmacología , Factor A de Crecimiento Endotelial Vascular/fisiología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/biosíntesis , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
18.
J Immunol ; 171(7): 3533-41, 2003 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-14500649

RESUMEN

Adjuvant arthritis (AA) is induced by immunizing Lewis rats with Mycobacterium tuberculosis suspended in adjuvant. The mycobacterial 65-kDa heat shock protein (HSP65) contains at least one epitope associated with the pathogenesis of AA: T cell clones that recognize an epitope formed by aa 180-188 of HSP65 react with self-cartilage and can adoptively transfer AA. Nevertheless, vaccination with HSP65 or some of its T cell epitopes can prevent AA by a mechanism that seems to involve cross-reactivity with the self-60-kDa HSP60. We recently demonstrated that DNA vaccination with the human hsp60 gene can inhibit AA. In the present work, we searched for regulatory epitopes using DNA vaccination with HSP60 gene fragments. We now report that specific HSP60 DNA fragments can serve as effective vaccines. Using overlapping HSP60 peptides, we identified a regulatory peptide (Hu3) that was specifically recognized by the T cells of DNA-vaccinated rats. Vaccination with Hu3, or transfer of splenocytes from Hu3-vaccinated rats, inhibited the development of AA. Vaccination with the mycobacterial homologue of Hu3 had no effect. Effective DNA or peptide vaccination was associated with enhanced T cell proliferation to a variety of disease-associated Ags, along with a Th2/3-like shift (down-regulation of IFN-gamma secretion and enhanced secretion of IL-10 and/or tumor growth factor beta1) in response to peptide Mt176-190 (the 180-188 epitope of HSP65). The regulatory response to HSP60 or its Hu3 epitope included both Th1 (IFN-gamma) and Th2/3 (IL-10/tumor growth factor beta1) secretors. These results show that regulatory mechanisms can be activated by immunization with relevant self-HSP60 epitopes.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Artritis Experimental/inmunología , Artritis Experimental/prevención & control , Chaperonina 60/inmunología , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Vacunas de ADN/inmunología , Traslado Adoptivo , Secuencia de Aminoácidos , Animales , Células Cultivadas , Chaperonina 60/administración & dosificación , Chaperonina 60/genética , Citocinas/antagonistas & inhibidores , Citocinas/biosíntesis , Citocinas/metabolismo , Epítopos de Linfocito T/administración & dosificación , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/aislamiento & purificación , Femenino , Humanos , Inyecciones Intramusculares , Activación de Linfocitos/inmunología , Datos de Secuencia Molecular , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/aislamiento & purificación , Plásmidos , Ratas , Ratas Endogámicas Lew , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/trasplante , Vacunas de ADN/administración & dosificación
19.
J Neurosci Res ; 71(2): 286-90, 2003 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-12503092

RESUMEN

We recently reported that immunization of mice with certain self-prion protein peptides induced specific T-cell and B-cell immune responses; importantly, this immunization was associated with a decrease in the number of protease-resistant PrP(Sc) particles recoverable in a transplanted, scrapie-infected syngeneic tumor. The present study was carried out to determine whether immunization with the immunogenic PrP peptides might influence the natural history of experimental scrapie in mice. We immunized C57BL/6 mice with self-prion peptides in complete Freund's adjuvant (CFA) or with CFA alone as a control and then infected the mice with mouse-adapted scrapie by injection either intraperitoneally or intracerebrally. We report here that immunization with CFA, irrespective of whether prion peptides were present in the inoculum, resulted in marked prolongation of survival of the mice, whether the challenge was intracerebral or intraperitoneal. Mice in the immunized and control groups that died contained equivalent amounts of PrP(Sc). Thus, CFA immunization has a therapeutic effect in experimental scrapie in mice, possibly by reducing the rate of PrP(Sc) accumulation in the brain.


Asunto(s)
Adyuvante de Freund/uso terapéutico , Enfermedades por Prión/terapia , Secuencia de Aminoácidos , Animales , Western Blotting , Modelos Animales de Enfermedad , Femenino , Adyuvante de Freund/inmunología , Inmunización , Ratones , Ratones Endogámicos C57BL , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/farmacología , Proteínas PrPSc/metabolismo , Enfermedades por Prión/inmunología , Enfermedades por Prión/mortalidad , Priones/efectos de los fármacos , Priones/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Scrapie/metabolismo , Tasa de Supervivencia , Factores de Tiempo
20.
J Immunol ; 170(1): 628-34, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12496452

RESUMEN

Beta-synuclein is a neuronal protein that accumulates in the plaques that characterize neurodegenerative diseases such as Parkinson's and Alzheimer's diseases. It has been proposed that immunization to peptides of plaque-forming proteins might be used therapeutically to help dissociate pathogenic plaques in the brain. We now report that immunization of Lewis rats with a peptide from beta-synuclein resulted in acute paralytic encephalomyelitis and uveitis. T cell lines and clones reactive to the peptide adoptively transferred the disease to naive rats. Immunoblotting revealed the presence of beta-synuclein in heavy myelin, indicating that the expression of beta-synuclein is not confined to neurons. These results add beta-synuclein to the roster of encephalitogenic self Ags, point out the potential danger of therapeutic autoimmunization to beta-synuclein, and alert us to the unsuspected possibility that autoimmunity to beta-synuclein might play an inflammatory role in the pathogenesis of neurodegeneration.


Asunto(s)
Autoantígenos/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Proteínas del Tejido Nervioso/inmunología , Subgrupos de Linfocitos T/inmunología , Uveítis/inmunología , Traslado Adoptivo , Secuencias de Aminoácidos/inmunología , Secuencia de Aminoácidos , Animales , Autoantígenos/administración & dosificación , Línea Celular/trasplante , Células Clonales/trasplante , Encefalomielitis Autoinmune Experimental/patología , Femenino , Antígenos de Histocompatibilidad Clase II/administración & dosificación , Antígenos de Histocompatibilidad Clase II/inmunología , Inmunización/métodos , Inyecciones Subcutáneas , Datos de Secuencia Molecular , Vaina de Mielina/química , Vaina de Mielina/inmunología , Vaina de Mielina/metabolismo , Proteínas del Tejido Nervioso/administración & dosificación , Proteínas del Tejido Nervioso/aislamiento & purificación , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/inmunología , Ratas , Ratas Endogámicas Lew , Sinucleínas , Células TH1/inmunología , Uveítis/patología , Sinucleína beta
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...