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1.
Dalton Trans ; 52(4): 902-908, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36504121

RESUMEN

In this research work, we present a study on time-sequenced plasma-enhanced atomic layer deposition (PE-ALD) processes towards the achievement of high-quality α-MoO3 thin films which are suitable for exfoliation. In particular, a conventional precursor injection method along with a boosted precursor delivery approach are discussed and analysed. In the latter, the proposed gas supply mechanism ensures a large number of deposited Mo atoms per unit of time, which, along with a proper thermal energy, leads to high-quality and oriented orthorhombic α-MoO3 films. The proposed boosted approach is also compared with post growth annealing steps, resulting in more effective achievement of a highly oriented orthorhombic α-MoO3 phase and less time consumption.


Asunto(s)
Calor , Molibdeno
3.
Nanomaterials (Basel) ; 14(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38202552

RESUMEN

MoS2 is a two-dimensional layered transition metal dichalcogenide with unique electronic and optical properties. The fabrication of ultrathin MoS2 is vitally important, since interlayer interactions in its ultrathin varieties will become thickness-dependent, providing thickness-governed tunability and diverse applications of those properties. Unlike with a number of studies that have reported detailed information on direct bandgap emission from MoS2 monolayers, reliable experimental evidence for thickness-induced evolution or transformation of the indirect bandgap remains scarce. Here, the sulfurization of MoO3 thin films with nominal thicknesses of 30 nm, 5 nm and 3 nm was performed. All sulfurized samples were examined at room temperature with spectroscopic ellipsometry and photoluminescence spectroscopy to obtain information about their dielectric function and edge emission spectra. This investigation unveiled an indirect-to-indirect crossover between the transitions, associated with two different Λ and K valleys of the MoS2 conduction band, by thinning its thickness down to a few layers.

4.
Br J Haematol ; 193(3): 497-505, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33620087

RESUMEN

Reliable biomarkers are needed to avoid diagnostic delay and its devastating effects in patients with primary central nervous system (CNS) lymphoma (PCNSL). We analysed the discriminating sensitivity and specificity of myeloid differentiation primary response (88) (MYD88) L265P mutation (mut-MYD88) and interleukin-10 (IL-10) in cerebrospinal fluid (CSF) of both patients with newly diagnosed (n = 36) and relapsed (n = 27) PCNSL and 162 controls (118 CNS disorders and 44 extra-CNS lymphomas). The concordance of MYD88 mutational status between tumour tissue and CSF sample and the source of ILs in PCNSL tissues were also investigated. Mut-MYD88 was assessed by TaqMan-based polymerase chain reaction. IL-6 and IL-10 messenger RNA (mRNA) was assessed on PCNSL biopsies using RNAscope technology. IL levels in CSF were assessed by enzyme-linked immunosorbent assay. Mut-MYD88 was detected in 15/17 (88%) PCNSL biopsies, with an 82% concordance in paired tissue-CSF samples. IL-10 mRNA was detected in lymphomatous B cells in most PCNSL; expression of IL-6 transcripts was negligible. In CSF samples, mut-MYD88 and high IL-10 levels were detected, respectively, in 72% and 88% of patients with newly diagnosed PCNSL and in 1% of controls; conversely, IL-6 showed a low discriminating sensitivity and specificity. Combined analysis of MYD88 and IL-10 exhibits a sensitivity and specificity to distinguish PCNSL of 94% and 98% respectively. Similar figures were recorded in patients with relapsed PCNSL. In conclusion, high detection rates of mut-MYD88 and IL-10 in CSF reflect, respectively, the MYD88 mutational status and synthesis of this IL in PCNSL tissue. These biomarkers exhibit a very high sensitivity and specificity in detecting PCNSL both at initial diagnosis and relapse. Implications of these findings in patients with lesions unsuitable for biopsy deserve to be investigated.


Asunto(s)
Biomarcadores de Tumor , Neoplasias del Sistema Nervioso Central , Interleucina-10/líquido cefalorraquídeo , Linfoma , Mutación Missense , Factor 88 de Diferenciación Mieloide/genética , Proteínas de Neoplasias , Adulto , Anciano , Sustitución de Aminoácidos , Biomarcadores de Tumor/líquido cefalorraquídeo , Biomarcadores de Tumor/genética , Biopsia , Neoplasias del Sistema Nervioso Central/líquido cefalorraquídeo , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/patología , Femenino , Humanos , Interleucina-10/genética , Linfoma/líquido cefalorraquídeo , Linfoma/genética , Masculino , Persona de Mediana Edad , Factor 88 de Diferenciación Mieloide/líquido cefalorraquídeo , Proteínas de Neoplasias/líquido cefalorraquídeo , Proteínas de Neoplasias/genética
5.
Nanotechnology ; 32(2): 025305, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33089826

RESUMEN

Aluminum bowtie nanoantennas represent a possibility to confine and enhance electromagnetic (EM) field at optical frequencies in subwavelength regions by using an abundant and inexpensive metal. The native oxidation process of this metal is often viewed as a limitation for its application in plasmonics. Here, we show that in close gap configurations, the high refractive index of the native aluminum oxide helps in squeezing the plasmonic mode in extremely reduced size volumes, providing a higher EM near-field confinement and enhancement in the bowtie antenna gaps than achieved in the pure aluminum counterpart. Hence, the study provides new perspectives in the use of such a plasmonic antenna geometry within this aluminum system, which can be useful for improving plasmonics-enabled effects such as surface-enhanced Raman scattering- and light-matter interaction in strong coupling regime.

6.
Blood Adv ; 4(15): 3648-3658, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32766857

RESUMEN

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is the standard treatment of diffuse large B-cell lymphoma (DLBCL). Primary DLBCL of the central nervous system (CNS) (primary central nervous system lymphoma [PCNSL]) is an exception because of the low CNS bioavailability of related drugs. NGR-human tumor necrosis factor (NGR-hTNF) targets CD13+ vessels, enhances vascular permeability and CNS access of anticancer drugs, and provides the rationale for the treatment of PCNSL with R-CHOP. Herein, we report activity and safety of R-CHOP preceded by NGR-hTNF in patients with PCNSL relapsed/refractory to high-dose methotrexate-based chemotherapy enrolled in a phase 2 trial. Overall response rate (ORR) was the primary endpoint. A sample size of 28 patients was considered necessary to demonstrate improvement from 30% to 50% ORR. NGR-hTNF/R-CHOP would be declared active if ≥12 responses were recorded. Treatment was well tolerated; there were no cases of unexpected toxicities, dose reductions or interruptions. NGR-hTNF/R-CHOP was active, with confirmed tumor response in 21 patients (75%; 95% confidence interval, 59%-91%), which was complete in 11. Seventeen of the 21 patients with response to treatment received consolidation (ASCT, WBRT, and/or lenalidomide maintenance). At a median follow-up of 21 (range, 14-31) months, 5 patients remained relapse-free and 6 were alive. The activity of NGR-hTNF/R-CHOP is in line with the expression of CD13 in both pericytes and endothelial cells of tumor vessels. High plasma levels of chromogranin A, an NGR-hTNF inhibitor, were associated with proton pump inhibitor use and a lower remission rate, suggesting that these drugs should be avoided during TNF-based therapy. Further research on this innovative approach to CNS lymphomas is warranted. The trial was registered as EudraCT: 2014-001532-11.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Células Endoteliales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Humanos , Recurrencia Local de Neoplasia , Prednisona/uso terapéutico , Proteínas Recombinantes de Fusión , Rituximab , Factor de Necrosis Tumoral alfa , Vincristina/uso terapéutico
7.
Hematol Oncol ; 38(3): 257-265, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32356913

RESUMEN

We report final results of a phase II trial addressing efficacy and feasibility of lenalidomide maintenance in patients with chemosensitive relapse of diffuse large B-cell lymphoma (DLBCL) not eligible for or failed after autologous stem cell transplantation (ASCT). Patients with relapsed DLBCL who achieved at least a partial response to salvage chemoimmunotherapy were enrolled and treated with lenalidomide 25 mg/day for 21 of 28 days for 2 years or until progression or unacceptable toxicity. Primary endpoint was 1-year PFS. Forty-six of 48 enrolled patients were assessable. Most patients had IPI ≥2, advanced stage and extranodal disease before the salvage treatment that led to trial registration; 28 (61%) patients were older than 70 years. Lenalidomide was well tolerated. With the exception of neutropenia, grade-4 toxicities occurred in <1% of courses. Three patients died of complications during maintenance and three died due to second cancers at 32 to 64 months. There were 13 SAEs recorded in 12 patients; all these patients but two recovered. Lenalidomide was interrupted due to toxicity in other 6 patients, and 25 patients required dose reduction (transient in 21). At 1 year from registration, 31 patients were progression free. After a median follow-up of 65 (range 39-124) months, 22 patients remain progression free, with a 5-year PFS of 48% ± 7%. The duration of response to lenalidomide was longer than response to prior treatment in 30 (65%) patients. Benefit was observed both in de novo and transformed DLBCL, germinal-center-B-cell and nongerminal-center-B-cell subtypes. Twenty-six patients are alive (5-year OS 62% ± 7%). With the limitations of a nonrandomized design, these long-term results suggest that lenalidomide maintenance might bring benefit to patients with chemosensitive relapse of DLBCL not eligible for or failed after ASCT. Lenalidomide was associated with durable disease control and was well tolerated in this elderly population. Further investigations on immunomodulatory drugs as maintenance in these high-risk patients are warranted.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Lenalidomida/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Terapia Recuperativa , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Linfoma de Células B Grandes Difuso/patología , Quimioterapia de Mantención , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Pronóstico , Tasa de Supervivencia
8.
Br J Radiol ; 91(1089): 20160725, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29750539

RESUMEN

OBJECTIVE: To report preliminary results of a cutting edge extreme hypofractionated treatment with concomitant boost to the dominant lesion for patients with early stage prostate cancer (PCa). METHODS: AIRC-IG-13218 is a prospective Phase II trial started in June 2015. Patients with low and intermediate risk PCa who met the inclusion criteria underwent extreme hypofractionated radiotherapy to the prostate (36.25 Gy in 5 fractions) and a simultaneous integrated boost to the dominant intraprostatic lesion (DIL) to 37.5 Gy. The DIL was identified by a multiparamentric MRI (mpMRI) co-registered with planning CT. Toxicity was assessed according to CTCAE v4.0 and RTOG/EORTC criteria. The preliminary evaluation of the first 13 patients was required to confirm the feasibility of the treatment before completing the enrollment of 65 patients. RESULTS: The first 13 patients completed the treatment between June 2015 and February 2016. With a median clinical follow-up of 17 months (range 11-26), no Grade 3 or 4 early toxicity was reported. CONCLUSIONS: Our preliminary data about early toxicity of an extreme hypofractionated schedule with concomitant boost on the DIL are encouraging. The higher number of patients expected for the trial and a longer follow-up are needed to confirm these results. Advances in knowledge: The use of mpMRI to identify and boost the DIL is an innovative and interesting approach to PCa. Our preliminary findings suggest that dose escalation using DIL boost and extremely hypofractionated radiotherapy regimens might be a safe approach, allowing for short and effective treatment of organ-confined PCa.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Hipofraccionamiento de la Dosis de Radiación , Radioterapia Asistida por Computador , Anciano , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Dosificación Radioterapéutica
9.
Ann Ital Chir ; 88: 201-205, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28874624

RESUMEN

AIM: To assess the sentinel-node identification rate at lymphoscintigraphy and its technical feasibility after neo-adjuvant treatments. MATERIAL OF STUDY: Between 2000 and 2013, 444 consecutive patients affected by primary locally advanced breast cancer were enrolled in this study. All individuals were candidate for neo-adjuvant treatments and for lymphoscintigraphy before surgery. RESULTS: The median age was 44 years at onset; almost one sentinel node was identified during lymphoscintigraphy in 430 cases. The detection rate at lymphoscintigraphy was 96.9% (95% CI, 94.8-98.1%). Considering the correlation between specific treatments and sentinel node identification rate, we verified that the detection rate did not vary significantly (p=0.53) according to the type of neo-adjuvant therapies administered to the patients. CONCLUSIONS: Our results demonstrated that lymphoscintigraphy for sentinel node identification is a safe and feasible procedure after neo-adjuvant therapies, independently of treatment types. KEY WORDS: Breast Cancer, Neo-Adjuvant Treatment, Sentinel lymphnode biopsy, Lymphoscintigraphy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/patología , Metástasis Linfática/diagnóstico por imagen , Linfocintigrafia , Terapia Neoadyuvante , Ganglio Linfático Centinela/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antraciclinas/administración & dosificación , Antraciclinas/farmacología , Antineoplásicos/farmacología , Antineoplásicos Hormonales/farmacología , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/cirugía , Estudios de Factibilidad , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/patología , Persona de Mediana Edad , Radiofármacos , Estudios Retrospectivos , Taxoides/administración & dosificación , Taxoides/farmacología , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Adulto Joven
10.
PLoS One ; 11(9): e0162456, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27603942

RESUMEN

B-cell superantigens (Sags) bind to conserved sites of the VH or VL regions of immunoglobulin molecules outside their complementarity-determining regions causing the apoptosis of normal cognate B cells. No attempts to investigate whether B-cell Sags are able to induce the apoptosis of cognate malignant B cells were reported. In the present study we show that protein L (PpL), secreted by Finegoldia magna, a B-cell Sag which interacts with κ+ bearing cells, induces the apoptosis of murine and human κ+ lymphoma B cells both in vitro and in vivo. Apoptosis was not altered by caspase-8 inhibitor. No alterations in the levels of Bid, Fas and Fas-L were found suggesting that PpL does not activate the extrinsic pathway of apoptosis. The involvement of the intrinsic pathway was clearly indicated by: i) alterations in mitochondrial membrane potential (ΔΨm) both in murine and human lymphoma cells exposed to PpL; ii) decreased levels of apoptosis in the presence of caspase-9 inhibitor; iii) significant increases of Bim and Bax protein levels and downregulation of Bcl-2; iv) the translocation from the cytoplasm to the mitochondria of Bax and Bim pro-apoptotic proteins and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor and v) the translocation of Bcl-2 protein from the mitochondria to the cytosol and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor. The possibility of a therapeutic use of Sags in lymphoma/leukemia B cell malignancies is discussed.


Asunto(s)
Apoptosis/inmunología , Linfocitos B/inmunología , Linfocitos B/patología , Proteínas Bacterianas/inmunología , Proteínas de Unión al ADN/inmunología , Linfoma de Células B/patología , Superantígenos/inmunología , Adolescente , Animales , Anexina A5/metabolismo , Linfocitos B/efectos de los fármacos , Antígeno B7-2/metabolismo , Proteína 11 Similar a Bcl2/metabolismo , Linfoma de Burkitt/genética , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Inhibidores de Caspasas/farmacología , Línea Celular Tumoral , Citosol/metabolismo , ADN de Neoplasias/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunoglobulina M/metabolismo , Cadenas kappa de Inmunoglobulina/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/inmunología , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Transporte de Proteínas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo , Receptor fas/genética , Receptor fas/metabolismo
11.
Tumori ; 102(5): 536-540, 2016 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-27514314

RESUMEN

INTRODUCTION: Of the different treatments for early prostate cancer, hypofractionated external-beam radiotherapy is one of the most interesting and studied options. METHODS: The main objective of this phase II clinical study is to evaluate the feasibility, in terms of the incidence of acute side effects, of a new ultra-hypofractionated scheme for low- or intermediate-risk prostate cancer patients treated with the latest imaging and radiotherapy technology, allowing dose escalation to the dominant intraprostatic lesion identified by multiparametric magnetic resonance imaging. Secondary endpoints of the study are the evaluation of the long-term tolerability of the treatment in terms of late side effects, quality of life, and efficacy (oncological outcome). RESULTS: The study is ongoing, and we expect to complete recruitment by the end of 2016. CONCLUSIONS: Like in previous studies, we expect ultra-hypofractionated radiation treatment for prostate cancer to be well tolerated and effective. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01913717.


Asunto(s)
Protocolos Clínicos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/radioterapia , Hipofraccionamiento de la Dosis de Radiación , Biomarcadores de Tumor , Fraccionamiento de la Dosis de Radiación , Humanos , Biopsia Guiada por Imagen , Imagen por Resonancia Magnética , Masculino , Estadificación de Neoplasias , Pronóstico , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
12.
Mol Carcinog ; 55(11): 1772-1785, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26509654

RESUMEN

The Receptor tyrosine kinase-like Orphan Receptor 1 (ROR1) is primarily expressed by neural crest cells during embryogenesis. Following a complete downregulation after birth, ROR1 was shown to re-express in various types of cancers. Little is known about ROR1 expression and function in melanoma. Here we show that ROR1 is aberrantly expressed in both melanoma cell lines and tumors and that its expression associates with poor Post-Recurrence Survival of melanoma. Using gain- and loss-of-function approaches we found that ROR1 enhances both anchorage-dependent and -independent growth of melanoma cells. In addition, ROR1 decreases cell adhesion and increases cell motility and migration. Mechanistically, ROR1 was found to induce upregulation of Akt and the mesenquimal markers N-cadherin and vimentin. The regulation of N-cadherin by ROR1 relies on both Akt dependent and independent mechanisms. ROR1 does not affect Wnt canonical pathway but was found to be engaged in a positive feedback loop with Wnt5a. In summary, we show that ROR1 contributes to melanoma progression and is a candidate biomarker of poor prognosis. Although further studies are needed to confirm this possibility, the present work indicates that ROR1 is a good prospective target for melanoma cancer therapy. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Cadherinas/metabolismo , Melanoma/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Melanoma/genética , Melanoma/metabolismo , Estudios Prospectivos , Transducción de Señal , Análisis de Supervivencia
13.
ACS Appl Mater Interfaces ; 5(8): 2908-14, 2013 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-23537058

RESUMEN

We show that assembled domains of magnetic iron-oxide nanoparticles (IONPs) are effective at increasing the dielectric permittivity of polydimethylsiloxane (PDMS) nanocomposites in the GHz frequency range. The assembly has been achieved by means of magnetophoretic transport and its efficacy, as well as the electromagnetic properties of the nanocomposite, has been found to depend on IONPs diameter. Remarkably, the dielectric permittivity increase has been obtained by keeping dielectric and magnetic losses very low, making us envision the suitability of nanocomposites based on aligned IONPs as substrates for radiofrequency applications.


Asunto(s)
Compuestos Férricos/química , Nanopartículas/química , Nanotecnología/instrumentación , Polímeros/química , Nanocompuestos/química , Tamaño de la Partícula
14.
PLoS One ; 5(12): e15694, 2010 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-21203530

RESUMEN

Superantigens bind to major histocompatibility complex class II molecules and interact with T cells expressing a particular T cell receptor Vß inducing a strong proliferation/deletion response of the superantigen-reactive T cells. However, there have been no attempts to investigate the ability of Sags to induce apoptosis in neoplastic T cells by signaling through the Vß region of their TCR. In the present study we show that bacterial and MMTV-encoded superantigens induce the apoptosis of AKR/J cognate lymphoma T cells both in vitro and in vivo. The Fas-Fas-L pathway was shown to be involved in the apoptosis of lymphoma T cells induced by bacterial superantigens. In vivo exposure to bacterial superantigens was able to improve the survival of lymphoma bearing mice. Moreover, the permanent expression of a retroviral encoded superantigen induced the complete remission of an aggressive lymphoma in a high percentage of mice. The possibility of a therapeutic use of superantigens in lymphoma/leukemia T cell malignancies is discussed.


Asunto(s)
Apoptosis , Linfoma de Células T/genética , Linfoma de Células T/inmunología , Superantígenos/metabolismo , Animales , Anticuerpos Monoclonales/química , Supervivencia Celular , Técnicas de Cocultivo , Proteína Ligando Fas/biosíntesis , Femenino , Citometría de Flujo/métodos , Humanos , Masculino , Virus del Tumor Mamario del Ratón/inmunología , Ratones , Receptores de Antígenos de Linfocitos T/metabolismo , Receptor fas/biosíntesis
15.
J Virol ; 82(15): 7422-31, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18495774

RESUMEN

Mouse mammary tumor virus (MMTV) is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. Here, we show in a natural model of MMTV infection that the virus causes early and progressive increases in superantigen (SAg)-specific Foxp3(+) regulatory T cells (T(reg)) in Peyer's patches (PP). These increases were shown to be dependent on the presence of dendritic cells. CD4(+) CD25(+) T cells from the PP of infected mice preferentially suppress the proliferative response of T cells to SAg-expressing antigen-presenting cells ex vivo. We investigated the influence of the depletion of CD25(+) cells at different stages of the infection. When CD25(+) cells were depleted before MMTV infection, an increase in the number of PP SAg-cognate Foxp3(-) T cells was found at day 6 of infection. Since the SAg response is associated with viral amplification, the possibility exists that T(reg) cells attenuate the increase in viral load at the beginning of the infection. In contrast, depletion of CD25(+) cells once the initial SAg response has developed caused a lower viral load, suggesting that at later stages T(reg) cells may favor viral persistence. Thus, our results indicated that T(reg) cells play an important and complex role during MMTV infection.


Asunto(s)
Factores de Transcripción Forkhead/análisis , Virus del Tumor Mamario del Ratón/inmunología , Infecciones por Retroviridae/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Infecciones Tumorales por Virus/inmunología , Animales , Antígenos Virales/inmunología , Linfocitos T CD4-Positivos/química , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Citometría de Flujo , Subunidad alfa del Receptor de Interleucina-2/análisis , Depleción Linfocítica , Ratones , Ratones Endogámicos BALB C , Ganglios Linfáticos Agregados/inmunología , Superantígenos/inmunología , Subgrupos de Linfocitos T/química , Carga Viral
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