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PURPOSE: Anatomic variations complicate surface landmark-guided needle placement, thereby increasing nerve blockade failure rate. However, little is understood about how anatomic distances change under different clinical conditions. As the cricoid cartilage is an easy and accurate landmark, we investigated changes in distance between the sixth or seventh cervical transverse processes (C6TP or C7TP) and the cricoid cartilage in neutral and extended supine positions. METHODS: Forty-two patients (16 men, 26 women) were included in this study. Distances between the cricoid cartilage and C6TP/C7TP were measured using ultrasonography with the patient in neutral and extended supine positions. RESULTS: C6TP and C7TP were caudally located at 6.0 ± 8.1 and 15.1 ± 7.2 mm, respectively, from the cricoid cartilage in the neutral supine position, and at 15.2 ± 8.0 and 25.3 ± 8.0 mm, respectively, in the extended supine position. In the extended supine position, the cricoid cartilage was more cephalad than C6TP and C7TP in all patients. The distance from the cricoid cartilage to C6TP was 12.1 ± 7.6 mm in men and 17.2 ± 7.7 mm in women. CONCLUSION: C6TP and C7TP are located approximately 15 and 25 mm, respectively, caudal to the cricoid cartilage in the extended supine position. Our results highlight the fact that there can be significant anatomic variation between the extended and neutral supine positions used in stellate ganglion block, which should be kept in mind when devising easily identifiable and palpable surface landmarks.
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Bloqueo Nervioso Autónomo/métodos , Cartílago Cricoides/anatomía & histología , Ganglio Estrellado/anatomía & histología , Adulto , Anciano , Vértebras Cervicales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Posición SupinaRESUMEN
Adenoviruses harboring the herpes simplex virus thymidine kinase (HSVtk) gene under the regulation of a trans-splicing ribozyme targeting human telomerase reverse transcriptase (hTERT-TR) show marked and specific antitumor activity. In addition to inducing tumor cell death by direct cytotoxicity, it is becoming clear that HSVtk also induces antitumor immunity. Programmed death ligand 1 (PD-L1) expressed on tumor cell surfaces mediates tumor-induced immunoresistance by inhibiting PD1-expressing tumor-infiltrating T cells. Here, we explored whether a soluble form of PD1 (sPD1-Ig), which blocks PD-L1, could synergize with TERT-TR-regulated HSVtk to enhance the adenoviral therapeutic efficacy by boosting antitumor immunity. Tumor antigen released by HSVtk-transduced tumors successfully primed tumor antigen-specific CD8 T cells via dendritic cells (DC). Regression of murine tumors was markedly enhanced when sPD1-Ig was incorporated into the adenovirus as compared with a single-module adenovirus expressing only HSVtk. This effect was abolished by CD8 T-cell depletion. Consistent with this, following adoptive transfer of tumor antigen-specific CD8 T cells into tumor-bearing Rag1(-/-) mice, dual-module adenovirus significantly enhanced CD8 T cell-mediated tumor rejection. In addition, secondary tumor challenge at a distal site was completely suppressed in mice treated with a dual-module adenovirus. These results suggest that a dual-targeting strategy to elicit both tumor antigen priming and tumor-induced immunoresistance enhances CD8 T cell-mediated antitumor immunity.
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Antígeno B7-H1/genética , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/uso terapéutico , Vectores Genéticos , Timidina Quinasa/genética , Adenoviridae/genética , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Antineoplásicos/farmacología , Antígeno B7-H1/metabolismo , Vacunas contra el Cáncer/inmunología , Línea Celular Tumoral , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Femenino , Inmunidad Celular/genética , Inmunidad Celular/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Linfocitos T Citotóxicos/inmunología , Telomerasa/genética , Telomerasa/metabolismo , Timidina Quinasa/metabolismo , Trans-EmpalmeRESUMEN
The increased activity of transglutaminase 2 (TG2) in various inflammatory and fibrotic conditions results in the development of numerous disease processes. Experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, is an inflammatory and demyelinating disease of the central nervous system and is mediated by many inflammatory cytokines and mediators. We examined the role of TG2 in encephalitogenic CD4(+) T cell responses and EAE development using mice lacking TG2 (TG2(-/-)). TG2(-/-) mice showed decreased disease severity as compared with wild-type (WT) mice. Treatment with cysteamine, a TG2 inhibitor, ameliorated disease severity in WT mice. Exacerbated disability in WT mice resulted from the increased infiltration of cytokine-producing CD4(+) T cells and sustained expression of inflammatory cytokines and mediators in the lesion. The increased number of IL-17- and IFN-γ-producing cells in the spinal cord resulted from peripheral expansion of these cells after immunization with myelin-derived antigen. In vitro differentiation of WT and TG2(-/-) splenocytes revealed that proliferation and activation-induced cell death did not differ, but differentiation into IL-17- or IFN-γ-producing cells was increased in WT mice. Adoptive transfer experiments revealed that pathogenic CD4(+) T cell differentiation and disease progression were caused by both the T cell-intrinsic and -extrinsic effects of TG2. This study is the first to report a pathogenic role for TG2 in the EAE progress and suggests that therapeutic targeting of TG2 may be effective against multiple sclerosis.
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Linfocitos T CD4-Positivos/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Proteínas de Unión al GTP/antagonistas & inhibidores , Inflamación/tratamiento farmacológico , Transglutaminasas/antagonistas & inhibidores , Traslado Adoptivo , Animales , Antígenos/inmunología , Antígenos/farmacología , Linfocitos T CD4-Positivos/enzimología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Proliferación Celular/efectos de los fármacos , Cisteamina/farmacología , Cisteamina/uso terapéutico , Progresión de la Enfermedad , Encefalomielitis Autoinmune Experimental/enzimología , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Proteínas de Unión al GTP/deficiencia , Proteínas de Unión al GTP/genética , Inflamación/enzimología , Inflamación/inmunología , Inflamación/patología , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Interleucina-17/biosíntesis , Interleucina-17/inmunología , Ratones , Ratones Noqueados , Vaina de Mielina/inmunología , Proteína Glutamina Gamma Glutamiltransferasa 2 , Índice de Severidad de la Enfermedad , Transducción de Señal , Médula Espinal/efectos de los fármacos , Médula Espinal/enzimología , Médula Espinal/inmunología , Transglutaminasas/deficiencia , Transglutaminasas/genéticaRESUMEN
Since clinically approved immunosuppressive drugs (e.g., cyclosporin A, FK506) possess dose-dependent biphasic effects that cause undesirable side effects on bone structure, including osteopenia, osteoporosis, and increased incidence of bone fractures, considerable effort has been devoted to the identification of immunosuppressive drugs that promote bone formation in a dose-dependent manner. Herein, we report the stereoselective synthesis of subglutinols A and B and present initial biological data showing the significant potential of subglutinol A as an immunosuppressive drug with dose-dependent osteogenic activity. We also show that activating protein 1 (AP-1) family transcription factors could be one of the key regulators for the anabolic activity of subglutinol A. Such drugs with dose-dependent osteogenic activity might help reduce bone-associated side effects and be clinically useful for bone tissue transplantation.
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Diterpenos/farmacología , Fusarium/química , Inmunosupresores/farmacología , Osteogénesis/efectos de los fármacos , Pironas/farmacología , Animales , Línea Celular , Cristalografía por Rayos X , Diterpenos/síntesis química , Diterpenos/química , Relación Dosis-Respuesta a Droga , Inmunosupresores/síntesis química , Inmunosupresores/química , Ratones , Modelos Moleculares , Conformación Molecular , Pironas/síntesis química , Pironas/química , EstereoisomerismoRESUMEN
Sphenopalatine ganglion block (SPGB) is a technique developed in the 1990s for the management of head and neck pain patients. Recently, transnasal sphenopalatine ganglion block (TN-SPGB) has been widely used for these patients; however, no objective methods exist for validating the success of TN-SPGB. In this study, we measured the changes in facial temperature before and 30 minutes after TN-SPGB by using digital infrared thermal imaging (DITI) to validate its success.The medical records of patients, who underwent TN-SPGB and facial DITI between January 2016 and December 2017, were reviewed. TN-SPGB and facial DITI were performed 36 times in 32 patients. The changes in facial temperatures measured at the forehead (V1), maxillary area (V2), and mandibular area (V3) by using DITI before and 30 minutes after TN-SPGB were recorded and compared. The temperatures on the ipsilateral and contralateral sides of these areas were also compared. The comparison between pain relief group and pain maintenance group was analyzed.After TN-SPGB, the temperature decreased significantly on both sides of V1 (Pâ=â.0208, 0.0181). No significant differences were observed between the ipsilateral and contralateral sides (P > .05). There was no correlation between changes in temperature and changes in pain score in the pain regions after the procedure (P > .05).The temperature decreased significantly in V1 area at 30 minutes after TN-SPGB compared with the temperature before TN-SPGB. Based on these results, we propose using DITI to measure temperature changes as an objective method for verifying the success of TN-SPGB.
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Temperatura Corporal , Bloqueo del Ganglio Esfenopalatino , Cara , Femenino , Humanos , Rayos Infrarrojos , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/fisiopatología , Manejo del Dolor , Estudios Retrospectivos , Termografía , Resultado del TratamientoRESUMEN
Opioids are used as a treatment for coughing. Recent studies have reported an antitussive effect of remifentanil during recovery from general anesthesia by suppressed coughing. The coughing reflex may differ throughout the respiratory tract from the larynx to the bronchi. But the proper dose of remifentanil to prevent cough during double-lumen tube (DLT) extubation is unknown.Twenty-five ASA physical status 1 and 2 patients, 20 to 65 years of age who were undergoing video-assisted thoracoscopic lung surgery requiring 1-lung ventilation were enrolled. The effective effect-site concentration (Ce) of remifentanil for 50% and 95% of patients (EC50 and EC95) for preventing cough was determined using the isotonic regression method with a bootstrapping approach, following the Dixon up-and-down method. Recovery profiles and hemodynamic values after anesthesia were compared between patients with cough and patients without cough.EC50 and EC95 of remifentanil was 1.670âng/mL [95% confidence interval (95% CI) 1.393-1.806] and 2.275âng/mL (95% CI 1.950-2.263), respectively. There were no differences in recovery profiles and hemodynamic values after anesthesia between patients with/without cough. No patients suffered respiratory complications during the emergence period.Remifentanil can be a safe and reliable method of cough prevention during emergence from sevoflurane anesthesia after thoracic surgery requiring DLT. EC50 and EC95 of remifentanil that suppresses coughing is 1.670 and 2.275âng/mL, respectively.
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Extubación Traqueal/efectos adversos , Tos/prevención & control , Éteres Metílicos/administración & dosificación , Piperidinas/administración & dosificación , Adulto , Anciano , Analgésicos Opioides/administración & dosificación , Anestésicos por Inhalación/administración & dosificación , Tos/etiología , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Remifentanilo , Sevoflurano , Resultado del Tratamiento , Adulto JovenRESUMEN
Pulmonary fibrosis is a potentially life-threatening disease that may be caused by overt or asymptomatic inflammatory responses. However, the precise mechanisms by which tissue injury is translated into inflammation and consequent fibrosis remain to be established. Here, we show that in a lung injury model, bleomycin induced the secretion of IL-6 by epithelial cells in a transglutaminase 2 (TG2)-dependent manner. This response represents a key step in the differentiation of IL-17-producing T cells and subsequent inflammatory amplification in the lung. The essential role of epithelial cells, but not inflammatory cells, TG2 was confirmed in bone marrow chimeras; chimeras made in TG2-deficient recipients showed reduced inflammation and fibrosis, compared with those in wild-type mice, regardless of the bone marrow cell phenotype. Epithelial TG2 thus appears to be a critical inducer of inflammation after noninfectious pulmonary injury. We further demonstrated that fibroblast-derived TG2, acting downstream of transforming growth factor-ß, is also important in the effector phase of fibrogenesis. Therefore, TG2 represents an interesting potential target for therapeutic intervention.
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Células Epiteliales/metabolismo , Proteínas de Unión al GTP/inmunología , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Neumonía/inmunología , Fibrosis Pulmonar/inmunología , Linfocitos T/inmunología , Transglutaminasas/inmunología , Aminas/análisis , Animales , Biotina/análogos & derivados , Biotina/análisis , Bleomicina/toxicidad , Western Blotting , Lavado Broncoalveolar , Colágeno/análisis , Cartilla de ADN/genética , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Proteínas de Unión al GTP/genética , Técnicas Histológicas , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neumonía/inducido químicamente , Neumonía/patología , Reacción en Cadena de la Polimerasa , Proteína Glutamina Gamma Glutamiltransferasa 2 , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/patología , ARN/genética , Linfocitos T/metabolismo , Transglutaminasas/genéticaRESUMEN
BACKGROUND: Acute graft-versus-host disease (GVHD) is a critical obstacle to bone marrow transplantation. Although numerous studies have described immunosuppression protocols to mitigate acute GVHD, the need still exists for a more efficient immunosuppressant with fewer side effects. Here, we evaluated the protective effect of CP-690550, a newly developed Janus kinase inhibitor, in an acute GVHD model. METHODS: CP-690550 was chemically synthesized. Acute GVHD was induced through the transfer of parent B6 (H-2) bone marrow and CD4 T cells into lethally irradiated (B6×bm12)F1 (H-2) mice. RESULTS.: CP-690550 treatments confined to days -3 to 11 of GVHD induction provided full protection against allogeneic, acute GVHD-related lethality and histopathology. An analysis of the initial donor-derived CD4 T-cell responses revealed that the inhibitory effects of CP-690550 were largely related to the suppression of donor CD4 T-cell-mediated interferon (IFN)-γ production. Enhanced inhibition of T helper 1 cell differentiation, rather than the inhibition of allogeneic CD4 T-cell proliferation or T helper 17 cell differentiation, was also confirmed in allogeneic mixed lymphocyte reactions. Because lethality was considerably delayed by the systemic blockade of IFN-γ, the principal protective effect of CP-690550 occurred through the modulation of IFN-γ production. CONCLUSION: The targeting of Janus kinase with a sensitive and specific inhibitor, CP-690550, conferred effective protection from acute GVHD induced by a semiallogeneic major histocompatibility complex class II-disparate combination. Protection from acute GVHD was largely mediated by the inhibition of IFN-γ production.
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Linfocitos T CD4-Positivos/inmunología , Enfermedad Injerto contra Huésped/prevención & control , Interferón gamma/antagonistas & inhibidores , Janus Quinasa 3/antagonistas & inhibidores , Pirimidinas/uso terapéutico , Pirroles/uso terapéutico , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/inmunología , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Citocinas/análisis , Células Dendríticas/citología , Células Dendríticas/inmunología , Enfermedad Injerto contra Huésped/inmunología , Interleucina-2/inmunología , Activación de Linfocitos/efectos de los fármacos , Depleción Linfocítica , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Fosforilación , Piperidinas , Factor de Transcripción STAT3/antagonistas & inhibidores , Factor de Transcripción STAT3/metabolismoRESUMEN
Immunosuppressive drugs are used to prevent rejection of transplanted organs and treat autoimmune diseases. Clinically approved immunosuppressive drugs possess undesirable side effects, including acute neurological toxicity, chronic nephrotoxicity, and osteoporosis. As a result, considerable efforts have been devoted to the identification of immunosuppressive natural products that lack cytotoxicity and undesirable side effects on bone structure. Subglutinols A (1 a) and B (1 b) are diterpene pyrones isolated from Fusarium subglutinans. Compounds 1 a and 1 b are equipotent in the mixed lymphocyte reaction assay and thymocyte proliferation assay (IC(50) = 0.1 microM). Owing to the lack of toxicity, 1 a and 1 b are expected to be promising new immunosuppressive drugs. Herein, we detail our efforts that have culminated in a stereoselective synthesis of 1 a and 1 b from the (S)-(+)-5-methyl-Wieland-Miescher ketone and determined their absolute stereochemistries. We also present initial biological data to show the great potential of 1 a as an immunosuppressive drug with dose-dependent osteogenic activity.
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Diterpenos/síntesis química , Inmunosupresores/síntesis química , Pironas/síntesis química , Animales , Línea Celular , Cobre/química , Diterpenos/química , Diterpenos/farmacología , Fusarium/química , Inmunosupresores/química , Inmunosupresores/farmacología , Ratones , Pironas/química , Pironas/farmacología , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
BACKGROUND: Effective intervention achieved by manipulating cell-mediated xenogeneic immune responses would critically increase the clinical feasibility of xenotransplantation as immediate hyperacute rejections become controllable through genetic modulations of donor organs. Endogenous negative regulatory signals like the programmed death 1 (PD-1)-programmed death ligand 1 (PD-L1) system are candidate targets for the control of cell-mediated xenogeneic immune response. METHODS: A porcine PD-L1 molecule was cloned using RACE (rapid amplification of cDNA ends) technology based on the human PD-L1 sequence. The functional effects of cloned porcine PD-L1 were tested on human CD4(+) T cell activation using porcine PD-L1-transfected bystander cells. Cellular proliferation was monitored by [3H] thymidine incorporation, and human T cell apoptosis was measured by flow cytometry. RESULTS: Porcine PD-L1 (GenBank accession number AY837780) was found to have 73.8% sequence homology with human PD-L1 and to contain two immunoglobulin domains in its extracellular region. Moreover, porcine PD-L1 expressed on Chinese hamster ovary (CHO) cells inhibited human CD4(+) T cell proliferation stimulated with anti-CD3 only or anti-CD3 plus anti-CD28. Percentages of apoptotic activated human T cells increased by over 30% in the presence of porcine PD-L1/CHO cells, and the addition of recombinant human PD-1-Fc fusion proteins during human T cell activation reversed the inhibitory effects of porcine PD-L1. CONCLUSIONS: Cloned porcine PD-L1 showed high sequence homology with human PD-L1 and a similar molecular structure. Moreover, porcine PD-L1 inhibited human CD4(+) T cell activation in human PD-1-dependent manner, and this involved activated T cell apoptosis. The authors suggest that PD-1-PD-L1 might play an important endogenous immune regulatory role during xenogeneic transplantation, and that the effective application of this system would improve transplanted xenogeneic organ survival.
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Antígenos CD/inmunología , Proteínas Reguladoras de la Apoptosis/inmunología , Apoptosis/inmunología , Homología de Secuencia de Aminoácido , Sus scrofa/inmunología , Trasplante Heterólogo/inmunología , Secuencia de Aminoácidos , Animales , Antígenos CD/genética , Proteínas Reguladoras de la Apoptosis/genética , Antígeno B7-H1 , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Células CHO , Proliferación Celular , Clonación Molecular , Cricetinae , Cricetulus , Humanos , Activación de Linfocitos , Datos de Secuencia MolecularRESUMEN
Although NKT cells expressing CD1d-reactive TCR exerted protective role in autoimmune diseases, the regulatory function of CD1d-dependent NKT cells in alloimmune responses has not been investigated thoroughly. Here, we demonstrated the regulatory effects of NKT cells using a pancreas islet transplantation model. CD40/CD154 blocking induced long-term graft survival in most B6 recipients, but B6.CD1d(-/-) recipients showed co-stimulation blockade-resistant rejection. Adoptive transfer of NKT cells into B6.CD1d(-/-) restored tolerizing capacity of co-stimulatory blockade. Activation of NKT cells was effective for the prolongation of graft survival and up-regulated membrane-bound TGF-beta expression transiently on their cell surface. The activated CD1d-dependent NKT cells inhibited alloantigen-driven cell proliferation through cell contacts and the beneficial effect of CD154 blocking for allograft survival was related to TGF-beta pathway. Thus, we can conclude that NKT cells are essential for the stable allograft survival and the regulatory function is dependent on, at least in part, TGF-beta engagement.
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Antígenos CD1/metabolismo , Supervivencia de Injerto/inmunología , Trasplante de Islotes Pancreáticos/inmunología , Células Asesinas Naturales/inmunología , Animales , Antígenos CD1/genética , Antígenos CD1d , Antígenos de Histocompatibilidad Clase II/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factores de Tiempo , Factor de Crecimiento Transformador beta/metabolismo , Tolerancia al Trasplante/inmunología , Regulación hacia ArribaRESUMEN
Regulatory T (Tr) cells have been shown to arise in the periphery during induction of peripheral tolerance. However, the mechanism involved remains elusive. In the present study, we investigated the potential role of transforming growth factor (TGF)-beta in the peripheral induction of regulatory phenotypes in the conventional CD4(+)CD25(-) T cells. Upon priming in the presence of TGF-beta, there was greatly enhanced expression of CD25, cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and the natural Tr cell-specific transcription factor Foxp3 in naive CD4(+)CD25(-) T cells. The CD25(+) cells that emerged later only in the TGF-beta-treated culture failed to express CD69, so distinguishing this population from activated CD25(+) effector cells. The TGF-beta-treated T cells entered an anergic state following restimulation, as judged by enhanced induction of programmed death (PD)-1, as well as impaired responses in terms of proliferation and IL-2 production. Importantly, the TGF-beta-costimulated CD4(+)CD25(-) T cells, prior to conversion to CD25(+) cells, were able to suppress the proliferation of responder T cells via contact-dependent and interleukin-10-independent mechanisms. Taken together, these results demonstrate that the existence of TGF-beta during early phase of priming is sufficient to induce CD4(+)CD25(-) Tr cells with anergic and immunoregulatory activities equivalent to thymus-derived CD4(+)CD25(+) Tr cells, and these cells are programmed to be CD25(+) cells under the prolonged resting conditions. Thus, our findings provide a novel mechanism by which TGF-beta mediates infectious tolerance in the periphery.
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Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Linfocitos T CD4-Positivos/inmunología , Comunicación Celular/inmunología , Activación de Linfocitos/inmunología , Receptores de Interleucina-2/inmunología , Factor de Crecimiento Transformador beta/farmacología , Animales , Antígenos de Diferenciación/inmunología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Humanos , Tolerancia Inmunológica/efectos de los fármacos , Tolerancia Inmunológica/inmunología , Interleucina-10/inmunología , Interleucina-2/inmunología , Lectinas Tipo C , Activación de Linfocitos/efectos de los fármacos , Ratones , Receptor de Muerte Celular Programada 1RESUMEN
OBJECTIVE: To examine whether the high incidence of herpes zoster in patients with systemic lupus erythematosus (SLE) is associated with the frequency of memory T cells specific to varicella zoster virus (VZV). METHODS: Whole blood samples from 47 subjects [24 patients with SLE, 11 with rheumatoid arthritis (RA) as a disease control, and 12 healthy negative controls] were stimulated with VZV antigen, stained for surface CD4 and CD8 and intracellularly stained for the cytokines interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), interleukin 4 (IL-4), and IL-10, followed by flow cytometry analyses. Correlations of VZV-specific T cell frequencies with the clinical status of patients were analyzed. RESULTS: Percentage of IFN-gamma-positive CD4 T cells was significantly lower in patients with SLE (0.043 +/- 0.009%) than in RA (0.102 +/- 0.019%) and healthy controls (0.126 +/- 0.025%) upon VZV stimulation. A similar pattern was seen in TNF-alpha-positive CD4 T cell responses. These low frequencies of VZV-specific CD4 T cells in patients with SLE were significantly related with disease activity (r = -0.435, p = 0.043). CONCLUSION: These data suggest that the high incidence of herpes zoster in patients with SLE was related to the intrinsic defects in controlling VZV reactivation, and thus VZV-specific CD4 T cell frequency could be another practical risk factor of herpes zoster in patients with SLE.