RESUMEN
Tarsal tunnel syndrome is an entrapment neuropathy of the posterior tibial nerve beneath the flexor retinaculum that can be precipitated by either intrinsic or extrinsic factors. We report a unique case of a posterior medial ankle joint capsular defect with localized fluid extravasation between the flexor digitorum longus and flexor hallucis longus leading to symptoms consistent with tarsal tunnel syndrome in a collegiate tennis player. This patient is a 19-year-old female with no past medical history who presented with symptoms consistent with tarsal tunnel syndrome. After confirmation with magnetic resonance imaging, the patient underwent capsular reconstruction with dermal allograft in combination with a tarsal tunnel release. The patient had improvement in pain and recovery of paresthesia 3 months postoperatively. At the latest follow-up of 1 year postoperatively, the patient has not had a recurrence of symptoms and has returned to the same level of competitive play. Many different causes of tarsal tunnel syndrome are described in the literature, but to our knowledge, there is no current literature that describes a defect in the tibiotalar joint capsule as a cause of tarsal tunnel syndrome.
RESUMEN
BACKGROUND: Production of the chemokine CCL2 by cells of the neurovascular unit (NVU) drives critical aspects of neuroinflammation. Suppression of CCL2 therefore holds promise in treating neuroinflammatory disease. Accordingly, we sought to determine if the compound bindarit, which inhibits CCL2 synthesis, could repress the three NVU sources of CCL2 most commonly reported in neuroinflammation--astrocytes, microglia and brain microvascular endothelial cells (BMEC)--as well as modify the clinical course of neuroinflammatory disease. METHODS: The effect of bindarit on CCL2 expression by cultured murine astrocytes, microglia and BMEC was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Bindarit action on mouse brain and spinal cord in vivo was similarly investigated by qRT-PCR following LPS injection in mice. And to further gauge the potential remedial effects of bindarit on neuroinflammatory disease, its impact on the clinical course of experimental autoimmune encephalomyelitis (EAE) in mice was also explored. RESULTS: Bindarit repressed CCL2 expression by all three cultured cells, and antagonized upregulated expression of CCL2 in both brain and spinal cord in vivo following LPS administration. Bindarit also significantly modified the course and severity of clinical EAE, diminished the incidence and onset of disease, and evidenced signs of disease reversal. CONCLUSION: Bindarit was effective in suppressing CCL2 expression by cultured NVU cells as well as brain and spinal cord tissue in vivo. It further modulated the course of clinical EAE in both preventative and therapeutic ways. Collectively, these results suggest that bindarit might prove an effective treatment for neuroinflammatory disease.
Asunto(s)
Quimiocina CCL2/antagonistas & inhibidores , Quimiocina CCL2/biosíntesis , Sistemas de Liberación de Medicamentos/métodos , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/prevención & control , Indazoles/administración & dosificación , Propionatos/administración & dosificación , Secuencia de Aminoácidos , Animales , Células Cultivadas , Femenino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismoRESUMEN
The injection of antigen into the ocular anterior chamber (AC) induces the generation of splenic CD4(+) and CD8(+) regulatory T (Treg) cells, specific for the antigen injected into the AC. These Treg cells inhibit the induction (CD4(+)) and also the expression (CD8(+)) of a delayed-type hypersensitivity response. The ability of AC-induced self-antigen-specific Treg cells in modulating autoimmunity is not well defined. Here we show that an injection of encephalitogenic myelin oligodendrocyte glycoprotein (MOG(35-55)) peptide into the anterior chamber of the eye (AC-MOG), before the induction of or during established experimental autoimmune encephalomyelitis (EAE) induced by MOG(35-55), suppresses the induction or progression of EAE, respectively. CD4(+) or CD8(+) splenic Treg cells induced by an injection of AC-MOG prevent EAE either at the inductive (priming) or at the progressive (effector) phase, respectively. This suppression of EAE by an AC-MOG injection or by intravenous transfer of splenic regulatory cells induced by an AC-MOG injection is specific for the antigen injected into the AC. Additionally, our data suggest that splenic CD8(+) Treg cells that suppress active EAE may use a transforming growth factor (TGF)-ß-dependent suppression mechanism while the suppression of the induction of EAE by the AC-induced CD4(+) Treg cells is independent of TGF-ß. Thus, we show for the first time that regulation of EAE at the priming or the chronic phase requires different phenotypes of Treg cells. Hence, it is important to consider the phenotype of Treg cells while designing effective cell-based therapies against autoimmune disorders.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/terapia , Ojo/inmunología , Linfocitos T Reguladores/inmunología , Animales , Encefalomielitis Autoinmune Experimental/fisiopatología , Ojo/citología , Femenino , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/inmunología , Glicoproteína Mielina-OligodendrócitoRESUMEN
Cbl-b is an E3 ubiquitin ligase that negatively regulates T cell activation. Cbl-b(-/-) mice develop spontaneous autoimmunity, and Cbl-b dysregulation has been described in both murine and human autoimmune diseases. Although the mechanisms underlying the development of autoimmunity in Cbl-b(-/-) mice are not yet clear, we have reported that Cbl-b(-/-) CD4(+)CD25(-) effector T cells (Teffs) are resistant to CD4(+)CD25(+) regulatory T cell (Treg)-mediated suppression in vitro and have suggested that this may be an important mechanism in the development of autoimmunity. To confirm the relevance of this resistance to autoimmune disease, we now show that Cbl-b(-/-) Teffs are resistant to suppression by Tregs in vivo and that this involves a resistance of truly naive Cbl-b(-/-) Teffs. Additionally, we show that Cbl-b(-/-) Tregs are fully functional in vivo, further suggesting that the regulatory abnormalities in Cbl-b(-/-) mice are related to defects in Teff, not Treg, function. To characterize the relevance of TGF-beta sensitivity in Treg resistance, we examined in vivo Th17 generation and report that Cbl-b(-/-) mice are able to mount a normal Th17 response in vivo. As Cbl-b(-/-) Teffs have been shown to be insensitive to the suppressive effects of TGF-beta in other in vivo models, the present results suggest that Cbl-b(-/-) Teffs demonstrate a context-dependent sensitivity to TGF-beta in vivo. Overall, our results suggest that resistance to Tregs may be a bona fide mechanism underlying autoimmunity and that Cbl-b(-/-) mice offer unique approaches for studying the interrelationships between Treg function, TGF-beta-mediated responses, and the development of autoimmunity.
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Proteínas Proto-Oncogénicas c-cbl/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T/inmunología , Factor de Crecimiento Transformador beta/inmunología , Animales , Anticuerpos/inmunología , Anticuerpos/farmacología , Enfermedades Autoinmunes/inmunología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/inmunología , Células Cultivadas , Citotoxicidad Inmunológica/efectos de los fármacos , Citotoxicidad Inmunológica/inmunología , Femenino , Citometría de Flujo , Enfermedad Injerto contra Huésped/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-12/inmunología , Interleucina-12/metabolismo , Interleucina-17/inmunología , Interleucina-17/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-cbl/genética , Linfocitos T/citología , Linfocitos T/metabolismo , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacologíaRESUMEN
The introduction of antigen into the anterior chamber (AC) of the eye induces the production of antigen-specific splenic CD8(+) regulatory T cells (AC-SPL cells) that suppress a delayed-type hypersensitivity (DTH) reaction in immunized mice. Because the generation of these regulatory T cells is also induced by exposure to transforming growth factor (TGF)-beta and antigen or F4/80(+) cells exposed to TGF-beta and antigen in vitro, we investigated (i) whether these cells are produced in dominant negative receptor for transforming growth factor beta receptor type II (dnTGFbetaRII) or Cbl-b(-/-) mice whose T cells are resistant to TGF-beta, (ii) whether DTH is suppressed by wild type (WT) CD8(+) AC-SPL cells in Cbl-b(-/-) and dnTGFbetaRII mice and (iii) the effect of antibodies to TGF-beta on the suppression of DTH by CD8(+) AC-SPL cells. DnTGFbetaRII immunized and Cbl-b(-/-) mice produced splenic CD8(+) regulatory cells after the intracameral injection of antigen and immunization. The suppression of a DTH reaction by CD8(+) AC-SPL cells in WT mice was blocked by the local inclusion of antibodies to TGF-beta when WT splenic CD8(+) AC-SPL cells were injected into the DTH reaction site. Moreover, the DTH reaction in immunized dnTGFbetaRII and Cbl-b(-/-) mice was not suppressed by the transfer of WT CD8(+) AC-SPL cells to the site challenged with antigen. In aggregate, these observations suggest that T cell sensitivity to TGF-beta is not an obligate requirement for the in vivo induction of CD8(+) AC-SPL T cells but the suppression of an in vivo DTH reaction by CD8(+) AC-SPL cells is dependent on TGF-beta.
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Proteínas Adaptadoras Transductoras de Señales/inmunología , Hipersensibilidad Tardía/inmunología , Proteínas Proto-Oncogénicas c-cbl/inmunología , Linfocitos T Reguladores/inmunología , Factor de Crecimiento Transformador beta/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Cámara Anterior/inmunología , Hipersensibilidad Tardía/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/inmunología , Proteínas Proto-Oncogénicas c-cbl/genética , Albúmina Sérica Bovina/inmunología , Linfocitos T Reguladores/metabolismo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
The injection of antigen into the anterior chamber (AC) induces the production of antigen-specific splenic CD8+ regulatory T cells (Tregs) /suppressor T cells that perform the local suppression of delayed-type hypersensitivity (DTH) responses. Because CD94/NKG2A-Qa-1-dependent interactions have been implicated in CD8+ Treg-mediated immune suppression and DBA/2J mice are deficient in CD94/NKG2R, we have utilized these mice to test the hypothesis that the CD94/NKG2A-Qa-1 system is essential to the induction and immunosuppressive function of CD8+ Tregs in anterior chamber-associated immune deviation (ACAID). We show that: (i) neither ACAID-mediated suppression of DTH to ovalbumin nor splenic Tregs/suppressor T cells was induced in DBA/2J mice that received an injection of antigen into the AC; (ii) splenic CD8+ Tregs from ACAID-induced DBA/2NCr mice suppressed the initiation of DTH when transferred to DBA/2J mice; (iii) following injection of antigen into the AC, intravenous administration of splenocytes or Peripheral Blood Mononuclear Cells (PBMC) isolated from DBA/2NCr but not from DBA/2J mice transferred suppression of DTH to DBA/2NCr mice; (iv) antibodies to CD94/NKG2A reduced the ACAID CD8+ T cell-mediated suppression of DTH and (v) The deficiency of such immune regulation in DBA/2J mice also correlated with a decreased number of Qa-1(b+) B cells, F4/80+ cells, a deficient number of CD94/NKG2AR and Qa-1 tetramer binding by CD8+ T cells. These results demonstrate that defective ACAID in DBA/2J mice involves multiple regulatory lesions resulting in a lack of induction of a CD8+ Treg response and possibly defective CD94/NKG2A-dependent suppression of peripheral cell-mediated immunity.
Asunto(s)
Cámara Anterior/inmunología , Linfocitos T CD8-positivos/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Subfamília D de Receptores Similares a Lectina de las Células NK/metabolismo , Receptores Inmunológicos/metabolismo , Animales , Presentación de Antígeno/inmunología , Antígenos/administración & dosificación , Antígenos/inmunología , Linfocitos T CD8-positivos/citología , Femenino , Hipersensibilidad Tardía/inmunología , Tolerancia Inmunológica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Subfamília C de Receptores Similares a Lectina de Células NK , Receptores de Células Asesinas Naturales , Bazo/citología , Bazo/inmunologíaRESUMEN
We have a tremendous opportunity not only to integrate women completely into the military but, more importantly, raise the standard of performance for all our service members. A standards-based approach appropriately defines gender neutral standards of physical performance based upon current demands of combat-arms specialties. The key is getting the standards right and sticking to those standards when challenged.
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Relaciones Interpersonales , Liderazgo , Medicina Militar/organización & administración , Personal Militar , Femenino , Humanos , Masculino , Factores Sexuales , Estados UnidosRESUMEN
Antigen injection into the eye's anterior chamber (AC) induces the antigen-specific suppression of delayed-type hypersensitivity (DTH) that is mediated by NKT cells and splenic CD8+ suppressor T cells. Because the AC, uveal tissues, the thymus and spleen required to induce anterior chamber-associated immune deviation (ACAID) have dense sympathetic innervations, we examined the effects of chemical sympathectomy of mice by 6-hydroxydopamine (6-OHDA) on the induction of the suppression of contact sensitivity to trinitrophenol (TNP) induced by the injection of TNP-bovine serum albumin (BSA) into the anterior chamber. DTH measured as contact sensitivity to picrylchloride was not induced in mice that received 6-OHDA before immunization with TNP-BSA. Although spleen cells from 6-OHDA-treated TNP-BSA-immunized mice produced IFN-gamma when stimulated by TNP-BSA, the number of DTH-initiating hepatic NKT cells was reduced markedly in 6-OHDA-treated mice. Chemically denervated mice did not produce splenic suppressor T cells or thymic NKT cells that activate splenic suppressor T cells. We suggest that an intact sympathetic nervous system (SNS) is required to maintain cellular immunoregulation.
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Linfocitos T CD8-positivos/inmunología , Bazo/citología , Sistema Nervioso Simpático/inmunología , Animales , Cámara Anterior/efectos de los fármacos , Cámara Anterior/inmunología , Formación de Anticuerpos , Desipramina/farmacología , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Hipersensibilidad Tardía/etiología , Hipersensibilidad Tardía/inmunología , Tolerancia Inmunológica/efectos de los fármacos , Inmunización/métodos , Terapia de Inmunosupresión , Interferón gamma/biosíntesis , Células Asesinas Naturales/inmunología , Leucocitos Mononucleares/inmunología , Hígado/citología , Hígado/inmunología , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Oxidopamina/toxicidad , Picratos/inmunología , Picratos/farmacología , Reología , Albúmina Sérica Bovina/inmunología , Bazo/inmunología , Simpatectomía/métodos , Sistema Nervioso Simpático/efectos de los fármacos , Simpaticolíticos/toxicidad , Timo/citología , Timo/inmunología , Ácido Trinitrobencenosulfónico/inmunologíaRESUMEN
T-cell-derived proteins that bind nominal (non-MHC-associated) antigen specifically (TABM) express V and C region epitopes of the T-cell receptor (TCR) for antigen and have a significant similarity in amino acid sequence to TCR alpha-chain V and C region. The presence of these immunoproteins in human serum and a specific increase in serum TABM in infectious disease, chemical sensitivity, and food intolerance suggest that TABM may impact on pathogenesis through the modulation of cell-mediated immunity, the antigen-specific concentration and delivery of immunoregulatory cytokines such as TGF-beta and elastase, and the induction of the release of substance P by sensory neurons. In this Minireview update, we describe advances in the detection and quantitation of human TABM by monoclonal antibodies, and the association of increased human serum TABM titers in infectious disease, chemical sensitivity, and food intolerance. We suggest that the immunomodulatory mode of action of these immunoproteins may be the antigen-specific focusing of cytokines associated with TABM.
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Antígenos/inmunología , Inmunoglobulinas/biosíntesis , Linfocinas/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Citocinas/inmunología , Epítopos/química , Epítopos/inmunología , Humanos , Inmunidad Celular , SolubilidadRESUMEN
PURPOSE: To characterize the immunoregulatory mechanisms in vitro of spleen cells that are activated by intracameral injection of antigen (AC-spleen cells). METHODS: AC-spleen cell regulation of in-vitro antigen-induced proliferation and interferon-gamma production by lymph node cells from TNP-BSA-immunized mice was quantified by co-culture of the lymph node cells with TNP-BSA and AC-spleen cells induced by intracameral TNP-BSA. Cytokine production was quantified by ELISA. RESULTS: AC-spleen cells produced significantly more IL-4 and IL-10 than spleen cells from TNP-BSA-immunized mice or naive spleen cells; unlike spleen cells from immunized mice, AC-spleen cells did not produce IFN-gamma. AC-splenic CD4(+), CD8(+), CD4(-)/CD8( -) (DN) T cells differentially suppressed antigen-induced proliferation and IFN-gamma production by immunized lymph node cells by a mechanism dependent on IL-10 and antigen. Cultures of lymph node cells, antigen, and AC-splenic T cells contained increased amounts of IL-10 and/or TGFbeta2. CONCLUSIONS: The differential, cytokine-dependent immunoregulatory effects of CD4( +) and CD8(+) AC-spleen cells observed in vitro parallel their effects in vivo. We suggest that the suppression of antigen-induced lymphocyte proliferation and IFN-gamma production by AC-spleen cells provides a useful in-vitro assay of the immunoregulatory activity of cell populations that are induced by the injection of antigen into the anterior chamber.
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Cámara Anterior/inmunología , Terapia de Inmunosupresión , Interferón gamma/biosíntesis , Ganglios Linfáticos/inmunología , Activación de Linfocitos/inmunología , Bazo/citología , Linfocitos T/inmunología , Animales , Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Técnicas de Cocultivo , Ensayo de Inmunoadsorción Enzimática , Femenino , Separación Inmunomagnética , Inmunofenotipificación , Inyecciones , Ratones , Ratones Endogámicos BALB C , Albúmina Sérica Bovina/inmunologíaRESUMEN
Anterior Chamber-Associated Immune Deviation (ACAID) induced by an intracameral injection of antigen generates antigen-specific regulatory splenic T cells that suppress specifically cell-mediated immunity specific for the injected antigen. Circulating F4/80(+) cells recovered from mice receiving an intracameral injection of antigen are thought to be ocular in origin and induce the development of thymic and splenic regulatory T cells. We have shown previously that after the intracameral injection of antigen there is a CCR2/CCL2-dependent infiltration of circulating F4/80(+) cells into the anterior chamber associated with the generation of circulating, ACAID-inducing F4/80(+) monocytes. Here we tested the hypothesis that the intracameral injection of antigen induces events in the anterior chamber that are associated with the induction of circulating immunoregulatory monocytes that induce the suppression of cell-mediated immunity. The intracameral injection of antigen resulted in aqueous humor (i) a time- dependent increase of CCL2 and CCL7, (ii) a transient increase in TNF-α, and (iii) an infiltration of CD11b(hi), Gr1(hi) and F4/80(+) as well as F4/80(-) and Gr1(hi) peripheral blood cells into the anterior chamber. Further characterization of these F4/80(+) cells revealed that they are Ly 6C(hi), LY6G(lo) or negative, 7/4 (LY6B)(hi), CD115(+), CD45(+), CD49B(+), and CD62 L(+). Antibody-mediated neutralization of TGF-ß in situ in the anterior chamber prevented the induction of circulating, ACAID-inducing monocytes and ACAID. These cells did not increase in the irides of ACAID-refractory CCR2-/- and CCL2-/- mice that received an intracameral injection of antigen. Our results extend our suggestion that ACAID is initiated as the result of a mild proinflammatory response to intracameral injection that results in the infiltration of a CCR2(+) subset of monocytes into the anterior chamber where there is a TGF-ß-dependent induction of an immunosuppressive phenotype in the infiltrated monocytes that recirculate to induce antigen-specific regulatory T cells.
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Cámara Anterior/inmunología , Antígenos de Diferenciación/inmunología , Hipersensibilidad Tardía/inmunología , Monocitos/inmunología , Análisis de Varianza , Animales , Cámara Anterior/citología , Humor Acuoso/citología , Humor Acuoso/metabolismo , Quimiocina CCL2/inmunología , Quimiocina CCL7/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ovalbúmina/administración & dosificación , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
BACKGROUND: CD8(+) suppressor T cells exert antigen-specific suppression of the expression of hypersensitivity by activated T cells. Therefore, CD8(+) suppressor T cells serve a major regulatory role for the control of active immunity. Accordingly, the number and/or activity of CD8(+) suppressor T cells should be influenced by an immune response to the antigen. To test this hypothesis we used an adoptive transfer assay that measures the suppression of the expression of delayed-type hypersensitivity (DTH) by CD8(+) suppressor T cells to quantify the antigen-specific suppression of DTH by these suppressor T cells. METHODS: Suppressor T cells were induced in the spleens of mice by the injection of antigen into the anterior chamber of an eye. Following this injection, the mice were immunized by the same antigen injected into the anterior chamber. Spleen cells recovered from these mice (AC-SPL cells) were titrated in an adoptive transfer assay to determine the number of AC-SPL cells required to effect a 50% reduction of antigen-induced swelling (Sw50) in the footpad of immunized mice challenged by antigen. RESULTS: Suppression of the expression of DTH is proportional to the number of AC-SPL cells injected into the site challenged by antigen. The number of AC-SPL cells required for a 50% reduction in DTH-induced swelling is reduced by injecting a cell population enriched for CD8(+) AC-SPL cells. Immunizing the mice receiving intracameral antigen to the same antigen decreases the RSw50 of AC-SPL cells required to inhibit the expression of DTH. CONCLUSIONS: The results provide the first quantitative demonstration that the numbers of antigen-specific splenic CD8(+) suppressor T cells are specifically amplified by antigen during an immune response.
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Linfocitos T CD8-positivos/inmunología , Traslado Adoptivo , Animales , Cámara Anterior , Antígenos/administración & dosificación , Femenino , Hipersensibilidad Tardía/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Bazo/citología , Bazo/inmunologíaRESUMEN
BACKGROUND: Pertussis toxin (PTX), an exotoxin of Bordetella pertussis, enhances the development of experimental autoimmune diseases such as experimental autoimmune uveitis (EAU) and experimental autoimmune encephalomyelitis (EAE) in rodent models. The mechanisms of the promotion of experimental autoimmune diseases by PTX may be based upon PTX-induced disruption of the blood eye/brain barriers facilitating the infiltration of inflammatory cells, the modulation of inflammatory cell migration and the enhancement of the activation of inflammatory cells. We hypothesized that the facilitation of experimental autoimmunity by PTX suggests that its influence on the in vivo immune response to auto-antigen may differ from its influence on non-self antigens. METHODOLOGY/PRINCIPAL FINDINGS: We have evaluated the effect of PTX on the simultaneous generation of delayed type hypersensitivity (DTH) responses and autoimmune responses to uveitogenic interphotoreceptor retinoid binding protein peptide (IRBP161-180), encephalitogenic myelin oligodendrocyte glycoprotein peptide (MOG35-55) or ovalbumin (OVA). PTX injection of mice immunized to IRBP peptide161-180 led to (i) the development of EAU as shown by histopathology of the retina, (ii) pro-inflammatory cytokine production by splenocytes in response to IRBP peptide161-180, and (iii) symptomatic EAE in mice immunized with encephalitogenic MOG peptide35-55. However, mice that received PTX had a reduced DTH response to IRBP161-180 peptide or MOG peptide35-55 when challenged distal to the site affected by autoreactive T cells. Moreover, footpad challenge with MOG35-55 peptide reduced EAE in mice immunized with MOG peptide. In contrast, the use of PTX when immunizing with OVA protein or an OVA immunogenic peptide did not affect the DTH response to OVA. CONCLUSIONS/SIGNIFICANCE: The results suggest that that the reduced DTH response in mice receiving PTX may be specific for autoantigens and autoantigen-reactive T cells are diverted away from ectopic sites that received the autoantigen and towards the tissue site of the autoantigen.
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Autoantígenos/inmunología , Hipersensibilidad Tardía/inmunología , Toxina del Pertussis/farmacología , Secuencia de Aminoácidos , Animales , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Citocinas/biosíntesis , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Proteínas del Ojo/química , Femenino , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/patología , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/química , Glicoproteína Mielina-Oligodendrócito , Ovalbúmina/inmunología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Proteínas de Unión al Retinol/química , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Uveítis/inducido químicamente , Uveítis/inmunología , Uveítis/metabolismo , Uveítis/patologíaRESUMEN
To determine the origin of peripheral blood mononulclear cells (PBMC) that activate regulatory T cells in anterior chamber-associated immune deviation (ACAID), fluorescein-labeled PBMC were intravenously injected into mice before the mice received an intracameral injection of antigen. Six-24 hr after intracameral injection, fluorescein-labeled PBMC increased in the iris. Twenty-four-48 hr labeled cells decreased in the iris and increased in the thymus and spleen. The entry of the labeled PBMC into the anterior chamber and subsequent production of PBMC that transfer ACAID required the expression of CCR2 by the PBMC and the production of the chemokine CCL2 by the recipient of the PBMC. The results suggest that the intracameral injection of antigen induces i) the infiltration of F4/80(+) PBMC into the AC, ii) where these PBMC are converted to a regulatory phenotype, and iii) recirculate to activate T cells that suppress cell-mediated immunity.
RESUMEN
The "immune privilege" that inhibits immune defense mechanisms that could lead to damage to sensitive ocular tissue is based on the expression of immunosuppressive factors on ocular tissue and in ocular fluids. In addition to this environmental protection, the injection of antigen into the anterior chamber or infection in the anterior chamber induces a systemic suppression of potentially damaging cell-mediated and humoral responses to the antigen. Here we discuss evidence that suggests that Anterior Chamber-Associated Immune Deviation (ACAID)(a) is initiated by an ocular response to moderate inflammation that leads to a systemic immunoregulatory response. Injection into the anterior chamber induces a rise in TNF-α and MCP-1 in aqueous humor and an infiltration of circulating F4/80(+) monocytes that home to the iris. The induction of ACAID is dependent on this infiltration of circulating monocytes that eventually emigrate to the thymus and spleen where they induce regulatory T cells that inhibit the inductive or effector phases of a cell-mediated immune response. ACAID therefore protects the eye from the collateral damage of an immune response to infection by suppressing a future potentially damaging response to infection.
RESUMEN
The injection of antigen into the anterior chamber (AC, intracameral injection) of a murine eye induces the generation of splenic CD8(+) regulatory T cells (AC-SPL cells) that effect the antigen-specific suppression of a delayed-type hypersensitivity (DTH) reaction. Here we show (i) for the first time that the local antigen-specific suppression of DTH-induced swelling in immunized mice either by an intracameral injection of antigen or by the direct injection of CD8(+) AC-SPL cells into an antigen-challenged site is associated with an absence of infiltrated mononuclear cells, (ii) that the local antigen-specific suppression of the DTH reaction by CD8(+) AC-SPL cells requires compatibility between the Qa-1 but not H2 antigen haplotype of the immunized recipient and the injected AC-SPL regulatory T cells, (iii) that the suppression of the DTH reaction by CD8(+) AC-SPL cells requires the expression of Qa-1 but not H2 antigens and is not due to bystander suppression.
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Linfocitos T CD8-positivos/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Hipersensibilidad Tardía/terapia , Terapia de Inmunosupresión , Animales , Cámara Anterior , Linfocitos T CD8-positivos/trasplante , Antígenos H-2/genética , Antígenos H-2/inmunología , Haplotipos , Antígenos de Histocompatibilidad Clase I/genética , Hipersensibilidad Tardía/patología , Tolerancia Inmunológica/genética , Ratones , Ovalbúmina/inmunología , Picratos/inmunología , Picratos/farmacología , Bazo/inmunología , Linfocitos T Reguladores/inmunologíaRESUMEN
CD4(+)FoxP3(+) Tregs are essential mediators of the peripheral immune response to self-antigens. Accordingly, the homeostatic regulation of Treg activity and number would impact on the immune response to both self- and non-self antigens. Because the sympathetic nervous system (SNS) interacts chemically and physically with the central and peripheral immune system and exerts a direct influence on antigen-presenting cells and effector lymphocytes, we have investigated the effect of chemical ablation of the SNS on the number and function of peripheral Treg. Removal of murine peripheral sympathetic innervation by 6-hydroxydopamine induced an increase in splenic and lymph node CD4(+)FoxP3(+) Tregs by a TGF-beta-dependent mechanism. Further, this increase in Tregs coincides with an inhibition of the induction of experimental autoimmune encephalomyelitis. Our results demonstrate that the SNS is an important contributor to the maintenance of peripheral Treg and TGF-beta acts as a bridge between the immune system and the nervous system. Neurological events mediated by the SNS, such as a stress response, may affect the number of T cells that regulate an immune response. Additionally, targeting Tregs via the SNS may be a novel approach to the prevention or treatment of autoimmune diseases.
Asunto(s)
Células Presentadoras de Antígenos/inmunología , Ganglios Linfáticos/inmunología , Bazo/inmunología , Sistema Nervioso Simpático/inmunología , Linfocitos T Reguladores/inmunología , Factor de Crecimiento Transformador beta/inmunología , Animales , Encefalomielitis Autoinmune Experimental/inmunología , Ganglios Linfáticos/inervación , Ratones , Ratones Noqueados , Oxidopamina/efectos adversos , Oxidopamina/farmacología , Bazo/inervación , Estrés Fisiológico/inmunología , Simpaticolíticos/efectos adversos , Simpaticolíticos/farmacologíaRESUMEN
Acute exposure of sensitized mice to antigen elicits allergic airway disease (AAD) characterized by Th2 cytokine-dependent pulmonary eosinophilia, methacholine hyperresponsiveness and antigen-specific IgE elevation. However, chronic exposure induces a local inhalational tolerance (LIT), with resolution of the airway responses but persistent systemic IgE production. To further determine if systemic immunologic responses were maintained during LIT, we assessed subcutaneous late phase responses to ovalbumin in this model. Sensitized and AAD mice developed small subcutaneous responses to ovalbumin, with footpad thickness increasing to 113.7 and 113.6% of baseline, respectively. In comparison, LIT mice developed marked foot swelling (141.6%). Histologic examination confirmed increased inflammation in the chronic animals, with a significant contribution by eosinophils. Thus, the resolution of airway inflammatory responses with chronic antigen inhalation is a localized response, not associated with loss of systemic responses to antigen.