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1.
Cancer Immunol Immunother ; 73(10): 195, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105809

RESUMEN

BACKGROUND: The efficacy of antibody-targeted therapy of solid cancers is limited by the lack of consistent tumour-associated antigen expression. However, tumour-associated antigens shared with non-malignant cells may still be targeted using conditionally activated-antibodies, or by chimeric antigen receptor (CAR) T cells or CAR NK cells activated either by the tumour microenvironment or following 'unlocking' via multiple antigen-recognition. In this study, we have focused on tissue factor (TF; CD142), a type I membrane protein present on a range of solid tumours as a basis for future development of conditionally-activated BiTE or CAR T cells. TF is frequently upregulated on multiple solid tumours providing a selective advantage for growth, immune evasion and metastasis, as well as contributing to the pathology of thrombosis via the extrinsic coagulation pathway. METHODS: Two well-characterised anti-TF monoclonal antibodies (mAb) were cloned into expression or transposon vectors to produce single chain (scFv) BiTE for assessment as CAR and CD28-CD3-based CAR or CD3-based BiTE. The affinities of both scFv formats for TF were determined by surface plasmon resonance. Jurkat cell line-based assays were used to confirm the activity of the BiTE or CAR constructs. RESULTS: The anti-TF mAb hATR-5 and TF8-5G9 mAb were shown to maintain their nanomolar affinities following conversion into a single chain (scFv) format and could be utilised as CD28-CD3-based CAR or CD3-based BiTE format. CONCLUSION: Because of the broad expression of TF on a range of solid cancers, anti-TF antibody formats provide a useful addition for the development of conditionally activated biologics for antibody and cellular-based therapy.


Asunto(s)
Receptores Quiméricos de Antígenos , Linfocitos T , Tromboplastina , Humanos , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/metabolismo , Tromboplastina/inmunología , Tromboplastina/metabolismo , Linfocitos T/inmunología , Inmunoterapia Adoptiva/métodos , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/genética , Neoplasias/inmunología , Neoplasias/terapia , Células Jurkat
2.
Sci Rep ; 6: 34789, 2016 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-27708419

RESUMEN

Human papillomavirus (HPV) is an epitheliotropic virus that is the primary causal agent for cervical cancer. Langerhans cells (LC) are skin antigen presenting cells that are reduced in number in HPV-infected skin. The aim of this study was to understand the immune-modulatory effects of HPV16 E7 on LC and on the CD8 T cell response to a skin-expressed antigen. To test this, HPV16 E7 was expressed in mouse skin keratinocytes with the model antigen ovalbumin (Ova). Similar to what is observed in HPV-infected human skin, LC numbers were significantly reduced in E7-expressing mouse skin. This shows that expression of the E7 protein alone is sufficient to mediate LC depletion. Expression of E7 with Ova in keratinocytes strongly suppressed the Ova-specific CD8+ T cell response in the skin draining lymph node. When tested in LC-ablated mice, the CD8 T cell response to skin-expressed Ova in control mice was not affected, nor was the T cell response to Ova restored in E7-expressing skin. These data indicate a role for E7 in regulation of LC homeostasis in the skin and in suppression of antigen specific CD8 T cell expansion, but suggest that these two effects occur independent of each other.


Asunto(s)
Linfocitos T CD8-positivos/fisiología , Células de Langerhans/virología , Proteínas E7 de Papillomavirus/metabolismo , Animales , Linfocitos T CD8-positivos/virología , Proliferación Celular , Regulación hacia Abajo , Oído/patología , Células Epidérmicas , Interacciones Huésped-Patógeno , Células de Langerhans/patología , Ratones Transgénicos , Ovalbúmina/metabolismo , Proteínas E7 de Papillomavirus/genética , Transducción Genética
3.
N Z Med J ; 129(1432): 51-8, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27356252

RESUMEN

AIM: To determine the excess costs attributable to surgical site infections (SSI) following primary hip and knee joint arthroplasty at Auckland City Hospital. METHODS: A retrospective case-control study. Cases were patients who developed a SSI following primary hip (THA) and knee arthroplasty (TKA) surgery within 90 days of the procedure. Cases were matched 1:2 with controls; patients whose primary hip and knee arthroplasty procedures were not complicated by infection. Controls were matched for age, gender, date of surgery, type of surgery, and ASA category. The length of stay (LOS) and hospital costs for the initial admission and subsequent readmission for infection were calculated from the clinical costing system at Auckland District Health Board. RESULTS: Eleven cases were identified; 3 following TKA, 7 following THA, and 1 following hemiarthroplasty of the hip. Infections were classified as superficial, 1, joint space, 1, and deep incisional, 9. Five SSI were identified during the initial admission for joint arthroplasty and 6 patients were readmitted with an SSI. Compared to the control patients, SSIs were associated with an excess mean cost of $40,121 and an excess mean LOS of 42 days. CONCLUSIONS: There is a significant increase in LOS and cost associated with SSI following primary THA and TKA at Auckland City Hospital. In addition to the excess cost associated with SSI, there are also opportunity costs resulting from their impact on elective surgical waiting lists. This reinforces the significant positive economic impact a successful strategy to reduce SSIs associated with primary joint arthroplasty procedures will have.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Infección de la Herida Quirúrgica/economía , Infección de la Herida Quirúrgica/prevención & control , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Estudios Retrospectivos , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología
6.
J Subst Abuse Treat ; 46(1): 15-21, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24029623

RESUMEN

Public schools are not traditional locations where screening, brief motivational counseling intervention and referral to treatment (SBIRT) are provided. This translational research study aimed to test the feasibility of conducting SBIRT in two urban New York schools and to examine its economic sustainability. In Spring 2012, 248 students were screened during non-academic classes: 42% of them (n=105) reported substance use (versus 28% reported in school-wide, paper anonymous survey). All but one of the positively screened students voluntarily accepted one or more brief intervention sessions and two students were referred to treatment. This school-based SBIRT model did not interfere with academic activities, was feasible to implement, and was attractive to students, teachers and administration. The data offer clear indication that further effectiveness testing is warranted and potentially valuable, however the sustainability of this model was not supported due to our lack of obtaining insurance information, authorization and reimbursement.


Asunto(s)
Tamizaje Masivo/métodos , Psicoterapia Breve/métodos , Derivación y Consulta/organización & administración , Trastornos Relacionados con Sustancias/diagnóstico , Adolescente , Consejo/métodos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Motivación , Ciudad de Nueva York , Instituciones Académicas , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/prevención & control , Investigación Biomédica Traslacional , Población Urbana
7.
J Subst Abuse Treat ; 43(1): 12-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22154827

RESUMEN

For reasons of safety and effectiveness, many forces in health care, especially the Affordable Care Act of 2010, are pressing for improved identification and management of substance use disorders within mainstream health care. Thus, standard information about patient substance use will have to be collected and used by providers within electronic health record systems (EHRS). Although there are many important technical, legal, and patient confidentiality issues that must be dealt with to achieve integration, this article focuses upon efforts by the National Institute on Drug Abuse and other federal agencies to develop a common set of core questions to screen, diagnose, and initiate treatment for substance use disorders as part of national EHRS. This article discusses the background and rationale for these efforts and presents the work to date to identify the questions and to promote information sharing among health care providers.


Asunto(s)
Confidencialidad , Registros Electrónicos de Salud/organización & administración , Trastornos Relacionados con Sustancias/diagnóstico , Humanos , Tamizaje Masivo/métodos , National Institute on Drug Abuse (U.S.) , Trastornos Relacionados con Sustancias/rehabilitación , Estados Unidos
9.
J Bone Joint Surg Br ; 90(1): 72-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18160503

RESUMEN

Osteoporosis and fragility fractures in men constitute a considerable burden in healthcare. We have reviewed 2035 men aged over 50 years with 2142 fractures to clarify the epidemiology of these injuries and their underlying risk factors. The prevalence of osteoporosis ranged between 17.5% in fractures of the ankle and 57.8% in those of the hip. The main risk factors associated with osteoporosis were smoking (47.4%), alcohol excess (36.2%), body mass index < 21 (12.8%) and a family history of osteoporosis (8.4%). Immobility, smoking, self-reported alcohol excess, a low body mass index, age >/=72 and loss in height were significantly more common among men with fractures of the hip than in those with fractures elsewhere.


Asunto(s)
Fracturas Óseas/epidemiología , Osteoporosis/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas , Traumatismos del Tobillo/epidemiología , Índice de Masa Corporal , Estudios de Cohortes , Fracturas de Cadera/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Escocia/epidemiología , Fumar
10.
Neurology ; 66(1): 133-5, 2006 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-16401865

RESUMEN

A number of familial syndromes of bilateral polymicrogyria (PMG) have been described, but reported unilateral PMG cases have generally been sporadic. The authors identified four families in which unilateral right-sided PMG on MRI was present in more than one individual, with pathologic confirmation in one. Core clinical features included contralateral hemiparesis, developmental delay, and focal seizures. The authors' findings suggest that unilateral PMG exists in a familial syndrome of probable germline genetic origin.


Asunto(s)
Corteza Cerebral/anomalías , Lateralidad Funcional/genética , Predisposición Genética a la Enfermedad/genética , Malformaciones del Sistema Nervioso/diagnóstico , Malformaciones del Sistema Nervioso/genética , Adolescente , Adulto , Niño , Preescolar , Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/fisiopatología , Epilepsias Parciales/diagnóstico , Epilepsias Parciales/genética , Salud de la Familia , Femenino , Humanos , Patrón de Herencia/genética , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Imagen por Resonancia Magnética , Masculino , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/genética , Paresia/diagnóstico , Paresia/genética , Paresia/fisiopatología , Linaje , Síndrome
11.
Dev Med Child Neurol ; 47(10): 666-72, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16174309

RESUMEN

The aim of this study was to establish the rate and spectrum of psychiatric disorder among children before and after temporal lobe surgery for epilepsy. Data were examined for associations between psychopathology and seizure outcome following surgery, or association between psychopathology and other variables, such as laterality of lesion, sex, cognitive level, and underlying pathology. Participants were 60 children (35 males, 25 females) who had focal seizures of temporal lobe origin and who had undergone temporal lobe resection between 1992 and 1998; mean age at time of operation 10 y 7 mo, (SD 4 y 11 mo) range 7 mo to 17 y 11 mo. Mean length of follow-up was 5.1 years (SD 2.3, range 2 to 10 y). Twenty-eight (47%) children had undergone right temporal lobectomy. Diagnosis of a psychiatric disorder was present in 50/60 (83%) children at some point, with high rates of psychiatric comorbidity. Common childhood psychiatric disorders of attention-deficit-hyperactivity disorder, oppositional defiant disorder/conduct disorder, and emotional disorders were present in about 25% of children. Disorders rarely seen in the general child population were over-represented: disruptive behaviour disorder--not otherwise specified (30/60 [50%]), and pervasive developmental disorder (autistic spectrum disorder; 23/60 [38%]). there was no significant relationship between pathology, sex, seizure frequency, or postoperative seizure outcome and psychiatric disorder, other than for pervasive developmental disorder. The same proportion of children had psychiatric diagnoses pre- and postoperatively (43/60 [72%] and 41/57 [72%] respectively). Although mental health problems are common in children undergoing temporal lobe resection, there are few predictors of psychiatric outcome following epilepsy surgery. Parents require counselling on these issues in the preoperative work-up.


Asunto(s)
Epilepsia/complicaciones , Epilepsia/cirugía , Trastornos Mentales/etiología , Lóbulo Temporal/cirugía , Adolescente , Niño , Preescolar , Comorbilidad , Epilepsia/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino
13.
J Subst Abuse Treat ; 27(2): 153-9, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15450648

RESUMEN

Buprenorphine and buprenorphine/naloxone (BUP) are newly approved for office-based treatment of opioid dependence. Federal and non-federal regulatory and monitoring agencies, national and international researchers, national professional organizations, researchers involved in monitoring, opioid treatment programs and the pharmaceutical industry met to synthesize and disseminate practical information to guide training, practice, monitoring, regulation and evaluation efforts with these medications. We performed a review of the literature, training curricula and practice guidelines and commissioned manuscripts describing recently completed, or still in progress, studies or field experiences with BUP treatment. A consensus process generated fifteen statements: (1) The federal government should collect baseline data on opioid-related deaths and morbidity to assess the effect of BUP on public health, (2) the patient limit for group practices should apply to individual physicians rather than group practices, (3 and 4) telephone and Internet-based physician and pharmacist support is needed, (5) clinicians who provide psychosocial services to opioid dependent patients should be informed of the role of BUP, (6) opioid-dependent patients should be instructed to present for induction in mild withdrawal, (7) the existing Center for Substance Abuse Treatment guidelines provide a reasonable induction protocol, (8) physicians should be prepared to use ancillary medications with BUP induction, (9) a physician or nurse must be available to the patient during the induction period, (10) concurrent counseling and support services are necessary, (11) detoxification without appropriate followup addiction treatment leads to rapid relapse and is not as effective as maintenance, (12) pregnant opioid-dependent women should be treated using good clinical practice including specialist addiction care and prenatal care, (13) BUP induction and withdrawal treatment may benefit from different designations for payment, (14) take-home medication options should be tailored to patients' needs, (15) there is a need for clinical and policy research in unique patient populations.


Asunto(s)
Atención Ambulatoria , Buprenorfina/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Trastornos Relacionados con Opioides/rehabilitación , Dependencia de Heroína/rehabilitación , Humanos , Guías de Práctica Clínica como Asunto , Estados Unidos
15.
Artículo en Inglés | MEDLINE | ID: mdl-11569657

RESUMEN

Appropriate investigation is essential to a full evaluation of any patient with urinary incontinence, as accurate diagnosis leads to correct treatment. This paper describes the various investigations for lower urinary tract dysfunction, and their main indications. They include the pad test, uroflowmetry, subtracted cystometry, and more complex investigations such as videocystourethrography, ambulatory urodynamics, urethral pressure profilometry, magnetic resonance imaging and electromyography. Although not every patient requires extensive investigation, appropriate use of tests of lower urinary tract function provides useful information on which to base appropriate treatment.


Asunto(s)
Incontinencia Urinaria/fisiopatología , Urodinámica/fisiología , Femenino , Humanos , Incontinencia Urinaria/diagnóstico
16.
BJOG ; 108(4): 408-13, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11305549

RESUMEN

OBJECTIVES: To investigate the impact of colposuspension for stress incontinence on the symptoms and quality of life of women undergoing both primary and repeat surgery for genuine stress incontinence and in addition to assess the use of a condition specific quality of life questionnaire as an outcome measure following surgery. DESIGN: Prospective case series: videocystourethrography performed before and between six and twelve months after surgery. Validated condition specific quality of life (QoL) questionnaires completed by women before and six to twelve months after surgery. SETTING: A tertiary referral Urogynaecology Unit in a teaching hospital. PARTICIPANTS: A consecutive series of 83 women undergoing colposuspension between March 1995 and December 1997. Pre-operative assessment and surgery was performed by, or was under the direct supervision of, the unit director. INTERVENTION: Modified Burch colposuspension. MAIN OUTCOME MEASURES: Objective results of surgery assessed with videocystourethrography. Subjective results evaluated using a condition specific QoL tool, the Kings Health Questionnaire (KHQ). Symptom severity was evaluated as a component of the condition specific QoL questionnaire. RESULTS: Objective cure was demonstrated in 92% of women undergoing primary surgery with an 8% incidence of de-novo detrusor instability and a 10% incidence of voiding difficulties. In the group of women having repeat surgery the objective cure rate was 81% with no de-novo detrusor instability and a 6% incidence of post-operative voiding difficulties. QoL scores improved in 95% of women. Improvements of over 25% were seen in 70% of women and of over 50% in 28%. However, 2.4% of women recorded a deterioration in QoL scores. CONCLUSIONS: Colposuspension performed in this setting, assessed using both objective and standardised subjective measures, completed by women themselves, appears to produce good objective and subjective results and leads to enhanced quality of life in the great majority of women.


Asunto(s)
Técnicas de Sutura , Incontinencia Urinaria de Esfuerzo/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Vagina/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Recurrencia , Reoperación , Encuestas y Cuestionarios/normas
17.
Immunity ; 14(2): 111-21, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11239444

RESUMEN

A recombinant antibody-lymphotoxin-alpha fusion protein induced an adaptive immune response protecting mice from melanoma. Importantly, this fusion protein elicited the formation of a lymphoid-like tissue in the tumor microenvironment containing L-selectin+ T cells and MHC class II+ antigen-presenting cells, as well as B and T cell aggregates. Furthermore, PNAd+/TCA4+ high endothelial venules were observed within the tumor, suggesting entry channels for naive T cell infiltrates. Over the course of therapy, a marked clonal expansion of certain TCR specificities occurred among tumor-infiltrating lymphocytes that displayed reactivity against melanoma cells and the TRP-2(180-188) peptide. Consequently, naive T cells may have been recruited to as well as primed and expanded in the lymphoid-like tissue induced by the lymphotoxin-alpha fusion protein at the tumor site.


Asunto(s)
Inmunotoxinas/uso terapéutico , Linfotoxina-alfa/uso terapéutico , Melanoma Experimental/inmunología , Melanoma Experimental/terapia , Animales , Anticuerpos Monoclonales/uso terapéutico , Endotelio Linfático/inmunología , Endotelio Linfático/patología , Humanos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Tejido Linfoide/inmunología , Tejido Linfoide/patología , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Trasplante de Neoplasias , Neoplasias de Tejido Conjuntivo/inmunología , Neoplasias de Tejido Conjuntivo/patología , Neoplasias de Tejido Conjuntivo/terapia , Proteínas Recombinantes de Fusión/uso terapéutico , Linfocitos T/inmunología , Linfocitos T/patología , Trasplante Isogénico
18.
Int Immunol ; 12(11): 1511-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11058570

RESUMEN

Dendritic cells (DC) are potent antigen-presenting cells and understanding their mechanisms of antigen uptake is important for loading DC with antigen for immunotherapy. The multilectin receptors, DEC-205 and macrophage mannose receptor (MMR), are potential antigen-uptake receptors; therefore, we examined their expression and FITC-dextran uptake by various human DC preparations. The RT-PCR analysis detected low levels of DEC-205 mRNA in immature blood DC, Langerhans cells (LC) and immature monocyte-derived DC (Mo-DC). Its mRNA expression increased markedly upon activation, indicating that DEC-205 is an activation-associated molecule. In Mo-DC, the expression of cell-surface DEC-205 increased markedly during maturation. In blood DC, however, the cell-surface expression of DEC-205 did not change during activation, suggesting the presence of a large intracellular pool of DEC-205 or post-transcriptional regulation. Immature Mo-DC expressed abundant MMR, but its expression diminished upon maturation. Blood DC and LC did not express detectable levels of the MMR. FITC-dextran uptake by both immature and activated blood DC was 30- to 70-fold less than that of LC, immature Mo-DC and macrophages. In contrast to immature Mo-DC, the FITC-dextran uptake by LC was not inhibited effectively by mannose, an inhibitor for MMR-mediated FITC-dextran uptake. Thus, unlike Mo-DC, blood DC and LC do not use the MMR for carbohydrate-conjugated antigen uptake and alternative receptors may yet be defined on these DC. Therefore, DEC-205 may have a different specificity as an antigen uptake receptor or contribute to an alternative DC function.


Asunto(s)
Antígenos CD , Células Dendríticas/metabolismo , Dextranos/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Lectinas Tipo C , Lectinas de Unión a Manosa , Glicoproteínas de Membrana/biosíntesis , Receptores de Antígenos/biosíntesis , Receptores de Superficie Celular/biosíntesis , Animales , Células COS , Células Dendríticas/inmunología , Colorantes Fluorescentes/metabolismo , Enfermedad de Hodgkin/metabolismo , Humanos , Isoquinolinas/metabolismo , Células de Langerhans/inmunología , Células de Langerhans/metabolismo , Lectinas/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Receptor de Manosa , Glicoproteínas de Membrana/sangre , Glicoproteínas de Membrana/genética , Antígenos de Histocompatibilidad Menor , Monocitos/inmunología , Monocitos/metabolismo , Pinocitosis/inmunología , ARN Mensajero/biosíntesis , Receptores de Superficie Celular/sangre , Receptores de Superficie Celular/genética , Células Tumorales Cultivadas
19.
Blood ; 96(7): 2628-31, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11001921

RESUMEN

Dendritic cells (DCs) disappear from lymph nodes 1 to 2 days after antigen presentation, presumably by apoptosis. To evaluate the role of death ligands in elimination of DCs, we analyzed the sensitivity of human DCs to CD95 ligand (CD95L) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). We found mature DCs to be resistant to killing via CD95L or TRAIL, whereas only immature DCs were partially sensitive. However, all DC populations expressed CD95, TRAIL-R2, and TRAIL-R3 at comparable levels, suggesting that sensitivity to death ligand-induced DC apoptosis is not regulated at the receptor level. Interestingly, mature DCs highly expressed the caspase 8 inhibitory protein cFLIP, whereas only low levels were detected in immature DCs. Thus, death ligand sensitivity proved to be dependent on DC maturation and inversely correlated with expression levels of cFLIP. Induction of apoptosis by TRAIL or CD95L does not seem to play a role in the elimination of mature DCs, but instead might serve to regulate immature DC populations.


Asunto(s)
Apoptosis , Células Dendríticas/fisiología , Glicoproteínas de Membrana/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Receptor fas/farmacología , Antígenos CD , Proteínas Reguladoras de la Apoptosis , Caspasa 8 , Caspasa 9 , Caspasas/metabolismo , Células Cultivadas , Células Dendríticas/química , Dinoprostona/farmacología , Resistencia a Medicamentos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Humanos , Inmunoglobulinas/análisis , Interleucina-1/farmacología , Interleucina-4/farmacología , Interleucina-6/farmacología , Glicoproteínas de Membrana/análisis , Ligando Inductor de Apoptosis Relacionado con TNF , Factor de Necrosis Tumoral alfa/análisis , Receptor fas/análisis , Antígeno CD83
20.
Eur J Immunol ; 30(9): 2612-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11009095

RESUMEN

In contrast to very immature dendritic cells (DC), mature DC are largely resistant to death by CD95 (CD95/APO-1) ligation. Investigation of other potential death-inducing ligands showed that mature DC were instead highly susceptible to apoptosis induced by cross-linking of MHC class II. Thus, increasing DC maturity correlates with increased resistance to CD95 killing, but an increased susceptibility to class II-mediated killing. Anti-I-A/I-E monoclonal antibodies (mAb) induced rapid (<2 h) apoptotic cell death in mature epidermal, spleen and bone marrow-derived DC, as determined by annexin/propidium iodide staining, morphological changes, decreased diploidy and loss in mitochondrial membrane potential. Although full class II-mediated killing required DC cytoskeletal motion, divalent cations and phosphatase activity, neither caspase activation, respiration, RNA or protein synthesis, NO production, nor CD95:CD95L interactions were required. Strikingly, DC pretreated by CD40 mAb cross-linking, but not by lipopolysaccharide or TNF-alpha, were completely resistant to class II-mediated killing. CD40-mediated protection was reduced in the presence of the SB202190 inhibitor of the mitogen-activated protein kinase p38 pathway, but appeared to be independent of p42/44 extracellular signal-related kinase or NF-KB activation. Our findings show that in addition to its role as an activator of antigen-presenting cell function, CD40 provides an important counter-signal against class II-induced apoptosis. Thus, these data point to an important role of the T cell in regulating DC survival.


Asunto(s)
Apoptosis , Antígenos CD40/fisiología , Células Dendríticas/fisiología , Antígenos de Histocompatibilidad Clase II/fisiología , Animales , Ligando de CD40 , Supervivencia Celular , Glicoproteínas de Membrana/fisiología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Transducción de Señal , Receptor fas/análisis
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