Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34873037

RESUMEN

TNF, produced largely by T and innate immune cells, is potently proinflammatory, as are cytokines such as IFN-γ and IL-17 produced by Th1 and Th17 cells, respectively. Here, we asked if TNF is upstream of Th skewing toward inflammatory phenotypes. Exposure of mouse CD4+ T cells to TNF and TGF-ß generated Th17 cells that express low levels of IL-17 (ROR-γt+IL-17lo) and high levels of inflammatory markers independently of IL-6 and STAT3. This was mediated by the nondeath TNF receptor TNFR2, which also contributed to the generation of inflammatory Th1 cells. Single-cell RNA sequencing of central nervous system-infiltrating CD4+ T cells in mouse experimental autoimmune encephalomyelitis (EAE) found an inflammatory gene expression profile similar to cerebrospinal fluid-infiltrating CD4+ T cells from patients with multiple sclerosis. Notably, TNFR2-deficient CD4+ T cells produced fewer inflammatory mediators and were less pathogenic in EAE and colitis. IL-1ß, a Th17-skewing cytokine, induced TNF and proinflammatory granulocyte-macrophage colony-stimulating factor (GM-CSF) in T cells, which was inhibited by disruption of TNFR2 signaling, demonstrating IL-1ß can function indirectly via the production of TNF. Thus, TNF is not just an effector but also an initiator of inflammatory Th differentiation.


Asunto(s)
Linfocitos T CD4-Positivos/fisiología , Inflamación/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Traslado Adoptivo , Animales , Colitis/inmunología , Colitis/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Ratones , Ratones Noqueados , Receptores Tipo II del Factor de Necrosis Tumoral/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Células Th17 , Factor de Necrosis Tumoral alfa/genética
2.
Int J Mol Sci ; 23(12)2022 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-35743272

RESUMEN

Mutations in optineurin, a ubiquitin-binding adaptor protein, cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease of motor neurons linked to chronic inflammation and protein aggregation. The majority of ALS patients, including those carrying the optineurin mutations, exhibit cytoplasmic mislocalization, ubiquitination, and aggregation of nuclear TAR DNA-binding protein 43 kDa (TDP-43). To address the crosstalk between optineurin and TDP-43, we generated optineurin knockout (KO) neuronal and microglial cell lines using the CRISPR/Cas9 approach. Interestingly, we observed that loss of optineurin resulted in elevated TDP-43 protein expression in microglial BV2 but not neuronal Neuro 2a and NSC-34 cell lines. No changes were observed at the mRNA level, suggesting that this increase was post-translationally regulated. To confirm this observation in primary cells, we then used microglia and macrophages from an optineurin loss-of-function mouse model that lacks the C-terminal ubiquitin-binding region (Optn470T), mimicking optineurin truncations in ALS patients. As observed in the BV2 cells, we also found elevated basal levels of TDP-43 protein in Optn470T microglia and bone marrow-derived macrophages. To test if inflammation could further enhance TDP-43 accumulation in cells lacking functional optineurin, we stimulated them with lipopolysaccharide (LPS), and we observed a significant increase in TDP-43 expression following LPS treatment of WT cells. However, this was absent in both BV2 Optn KO and primary Optn470T microglia, which exhibited the same elevated TDP-43 levels as in basal conditions. Furthermore, we did not observe nuclear TDP-43 depletion or cytoplasmic aggregate formation in either Optn470T microglia or LPS-treated WT or Optn470T microglia. Taken together, our results show that optineurin deficiency and insufficiency post-translationally upregulate microglial TDP-43 protein levels and that elevated TDP-43 levels in cells lacking functional optineurin could not be further increased by an inflammatory stimulus, suggesting the presence of a plateau.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Inflamación , Lipopolisacáridos/farmacología , Ratones , Microglía/metabolismo , Mutación , Factor de Transcripción TFIIIA/genética , Factor de Transcripción TFIIIA/metabolismo , Ubiquitinas/genética
3.
Anal Chem ; 93(22): 7993-8001, 2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34043322

RESUMEN

Current-time recordings of emulsified toluene microdroplets containing 20 mM Ferrocene (Fc), show electrochemical oxidation peaks from individual adsorption events on disk microelectrodes (5 µm diameter). The average droplet diameter (∼0.7 µm) determined from peak area integration was close to Dynamic Light Scattering measurements (∼1 µm). Random walk simulations were performed deriving equations for droplet electrolysis using the diffusion and thermal velocity expressions from Einstein. The simulations show that multiple droplet-electrode collisions, lasting ∼0.11 µs each, occur before a droplet wanders away. Updating the Fc-concentration at every collision shows that a droplet only oxidizes ∼0.58% of its content in one collisional journey. In fact, it would take ∼5.45 × 106 collisions and ∼1.26 h to electrolyze the Fc in one droplet with the collision frequency derived from the thermal velocity (∼0.52 cm/s) of a 1 µm-droplet. To simulate adsorption, the droplet was immobilized at first contact with the electrode while the electrolysis current was computed. This approach along with modeling of instrumental filtering, produced the best match of experimental peaks, which were attributed to electrolysis from single adsorption events instead of multiple consecutive collisions. These results point to a heightened sensitivity and speed when relying on adsorption instead of collisions. The electrochemical current for the former is limited by the probability of adsorption per collision, whereas for the latter, the current depends on the collision frequency and the probability of electron transfer per collision (J. Am. Chem. Soc. 2017, 139, 16923-16931).

4.
PLoS Biol ; 16(1): e2004111, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29357353

RESUMEN

Nuclear factor of activated T cells (NFAT) transcription factors are required for induction of T-cell cytokine production and effector function. Although it is known that activation via the T-cell antigen receptor (TCR) results in 2 critical steps, calcineurin-mediated NFAT1 dephosphorylation and NFAT2 up-regulation, the molecular mechanisms underlying each are poorly understood. Here we find that T cell p38, which is activated by an alternative pathway independent of the mitogen-activated protein (MAP) kinase cascade and with different substrate specificities, directly controls these events. First, alternatively (but not classically) activated p38 was required to induce the expression of the AP-1 component c-Fos, which was necessary for NFAT2 expression and cytokine production. Second, alternatively (but not classically) activated p38 phosphorylated NFAT1 on a heretofore unidentified site, S79, and in its absence NFAT1 was unable to interact with calcineurin or migrate to the nucleus. These results demonstrate that the acquisition of unique specificities by TCR-activated p38 orchestrates NFAT-dependent T-cell functions.


Asunto(s)
Factores de Transcripción NFATC/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Animales , Calcineurina , Comunicación Celular , Humanos , Inmunidad Celular/genética , Inmunidad Celular/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción NFATC/metabolismo , Fosforilación , Proteolisis , Proteínas Proto-Oncogénicas c-fos , Receptores de Antígenos de Linfocitos T/fisiología , Especificidad por Sustrato , Linfocitos T , Factores de Transcripción
5.
Sensors (Basel) ; 21(24)2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34960443

RESUMEN

This paper proposes a high-order MIMO antenna operating at 3.5 GHz for a 5G new radio. Using an eighth-mode substrate integrated waveguide (EMSIW) cavity and considering a typical smartphone scenario, a two-element MIMO antenna is developed and extended to a twelve-element MIMO. These MIMO elements are closely spaced, and by employing multiple diversity techniques, high isolation is achieved without using a decoupling network. The asymmetric EMSIW structures resulted in radiation pattern diversity, and their orthogonal placement provides polarization diversity. The radiation characteristics and diversity performance are parametrically optimized for a two-element MIMO antenna. The experimental results exhibited 6.0 dB and 10.0 dB bandwidths of 250 and 100 MHz, respectively. The measured and simulated radiation patterns are closely matched with a peak gain of 3.4 dBi and isolation ≥36 dB. Encouraged with these results, higher-order MIMO, namely, four- and twelve-element MIMO are investigated, and isolation ≥35 and ≥22 dB are achieved, respectively. The channel capacity is found equal to 56.37 bps/Hz for twelve-element MIMO, which is nearly 6.25 times higher than the two-element counterpart. The hand and head proximity analysis reveal that the proposed antenna performances are within the acceptable limit. A detailed comparison with the previous works demonstrates that the proposed antenna offers a simple, low-cost, and compact MIMO antenna design solution with a high diversity performance.


Asunto(s)
Teléfono Inteligente , Tecnología Inalámbrica , Diseño de Equipo , Registros
6.
Nat Commun ; 15(1): 2017, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443376

RESUMEN

HIV-1 infection elevates the risk of developing various cancers, including T-cell lymphoma. Whether HIV-1-encoded proteins directly contribute to oncogenesis remains unknown. We observe that approximately 1-5% of CD4+ T cells from the blood of people living with HIV-1 exhibit over-duplicated centrioles, suggesting that centrosome amplification underlies the development of HIV-1-associated cancers by driving aneuploidy. Through affinity purification, biochemical, and cellular analyses, we discover that Vpr, an accessory protein of HIV-1, hijacks the centriole duplication machinery and induces centrosome amplification and aneuploidy. Mechanistically, Vpr forms a cooperative ternary complex with an E3 ligase subunit, VprBP, and polo-like kinase 4 (Plk4). Unexpectedly, however, the complex enhances Plk4's functionality by promoting its relocalization to the procentriole assembly and induces centrosome amplification. Loss of either Vpr's C-terminal 17 residues or VprBP acidic region, the two elements required for binding to Plk4 cryptic polo-box, abrogates Vpr's capacity to induce these events. Furthermore, HIV-1 WT, but not its Vpr mutant, induces multiple centrosomes and aneuploidy in human primary CD4+ T cells. We propose that the Vpr•VprBP•Plk4 complex serves as a molecular link that connects HIV-1 infection to oncogenesis and that inhibiting the Vpr C-terminal motif may reduce the occurrence of HIV-1-associated cancers.


Asunto(s)
VIH-1 , Linfocitos T , Humanos , Centrosoma , Carcinogénesis , Transformación Celular Neoplásica , Aneuploidia , Linfocitos T CD4-Positivos
7.
Cureus ; 15(12): e51410, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38292968

RESUMEN

INTRODUCTION: The Breast Imaging-Reporting and Database System (BI-RADS) category 4 is designated for breast lumps that do not display the typical features of malignancy but still raise enough suspicion to warrant a recommendation for a biopsy, as malignancy cannot be ruled out through imaging alone. The main objective of this study was to investigate the sonographic characteristics and pathology correlation of BI-RADS 4 breast lesions and determine the positive predictive rate of BI-RADS 4 lesions in diagnosing breast cancer, using histopathology as the gold standard. METHODS: This was a cross-sectional study conducted at the Department of Radiology, Aga Khan University Hospital in Karachi, spanning from May 2021 to August 2022, with a duration of 15 months. The study focused on female patients over the age of 18 who presented with suspicious breast lesions on ultrasound. Both mammography and ultrasound-guided core needle biopsy were performed on these patients, followed by a detailed histopathological evaluation of the biopsy specimens. To calculate the positive predictive value (PPV), true positive cases were identified through both histopathology and ultrasonography. RESULTS: A total of 227 cases were categorized as BI-RADS 4 lesions, with the patients' mean age being 47.8 ± 14.3 years (range: 17 - 88). Among the biopsied lesions, 101 cases were confirmed to be true positive for breast malignancies, resulting in a PPV for malignancy of 44.9%. Conversely, there were 124 false positive cases out of the 227 BI-RADS 4 category lesions (54.63%). The primary indication for presentation was a breast lump, and out of the 101 confirmed malignant cases, 70 (69.3%) were associated with malignancy. CONCLUSION: BI-RADS 4 can be utilized to assess suspicious breast lumps; however, for more reliable results and to avoid false negatives, histopathological confirmation should complement the imaging findings.

8.
Res Sq ; 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37645926

RESUMEN

HIV-1 infection elevates the risk of developing various cancers, including T-cell lymphoma. Whether HIV-1-encoded proteins directly contribute to oncogenesis remains unknown. We observed that approximately 1-5% of CD4+ T cells from the blood of people living with HIV-1 exhibit over-duplicated centrioles, suggesting that centrosome amplification underlies the development of HIV-1-associated cancers by driving aneuploidy. Through affinity purification, biochemical, and cell biology analyses, we discovered that Vpr, an accessory protein of HIV-1, hijacks the centriole duplication machinery and induces centrosome amplification and aneuploidy. Mechanistically, Vpr formed a cooperative ternary complex with an E3 ligase subunit, VprBP, and polo-like kinase 4 (Plk4). Unexpectedly, however, the complex enhanced Plk4's functionality by promoting its relocalization to the procentriole assembly and induced centrosome amplification. Loss of either Vpr's C-terminal 17 residues or VprBP acidic region, the two elements required for binding to Plk4 cryptic polo-box, abrogated Vpr's capacity to induce all these events. Furthermore, HIV-1 WT, but not its Vpr mutant, induced multiple centrosomes and aneuploidy in primary CD4+ T cells. We propose that the Vpr•VprBP•Plk4 complex serves as a molecular link that connects HIV-1 infection to oncogenesis and that inhibiting the Vpr C-terminal motif may reduce the occurrence of HIV-1-associated cancers.

9.
Methods Mol Biol ; 2422: 191-201, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34859407

RESUMEN

Proximity ligation assay (PLA), also referred to as Duolink® PLA technology, permits detection of protein-protein interactions in situ (<40 nm distance) at endogenous protein levels. It exploits specific antibodies identifying (either directly or indirectly) the two proteins of interest and takes advantage of specific DNA primers covalently linked to the antibodies. A hybridization step followed by a PCR amplification with fluorescent probes then permits visualization of spots of proximity by fluorescence microscopy.


Asunto(s)
Microscopía Fluorescente , Anticuerpos , Cartilla de ADN , Mapeo de Interacción de Proteínas , Proteínas
10.
Curr Pharm Biotechnol ; 22(8): 1061-1068, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32962612

RESUMEN

BACKGROUND: Enhydra fluctuans Lour, a tropical herb, commonly known as helencha or harkuch, belongs to the family Asteraceae. It is an edible semi-aquatic herbaceous vegetable plant with serrate leaves and grows commonly in different parts of the world. Enhydra fluctuans possesses potential pharmacological role against inflammation, cancer, diarrhea, microbial infection, diabetes, etc. Aim: This review aims to provide the most current information on the botanical characterization, distribution, traditional uses, chemical constituents, as well as the pharmacological activities of Enhydra fluctuans Lour. MATERIALS AND METHODS: The recently updated information on Enhydra fluctuans was gathered from scientific journals, books, and worldwide accepted scientific databases via a library and electronic search PubMed, Elsevier, Google Scholar, Springer, Scopus, Web of Science, Wiley online library. All of the full-text articles and abstracts related to Enhydra were screened. The most important and relevant articles were carefully chosen for study in this review. RESULTS: Crude extracts and isolated compounds of Enhydra fluctuans Lour have been reported to be pharmacologically active against cytoprotective, analgesic and anti-inflammatory, antimicrobial, anticancer, antidiarrheal, antihelmintic, CNS depressant, hepatoprotective, thrombolytic, antidiabetic, antioxidant, phagocytic and cytotoxic, and neuroprotective potential activities. DISCUSSION: Phytochemical analysis from different studies has reported Germacranolide, Sesquiterpene lactone, Flavonoid, Essential oil, Steroid, Diterpenoid, Melampolide, Sesquiterpene lactone, and Isoflavone glycoside as major compounds of Enhydra fluctuans Lour. CONCLUSION: However, more research is needed to explore the mode of action of bioactive components of the plant and its therapeutic capabilities.


Asunto(s)
Asteraceae/química , Extractos Vegetales/farmacología , Analgésicos/aislamiento & purificación , Analgésicos/farmacología , Animales , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Depresores del Sistema Nervioso Central/aislamiento & purificación , Depresores del Sistema Nervioso Central/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Humanos , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacología , Fitoquímicos/farmacología , Fitoterapia , Hojas de la Planta
11.
Carbohydr Res ; 496: 108130, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32863019

RESUMEN

Direct unimolar one-step valeroylation of methyl α-d-mannopyranoside (MDM) furnished mainly 6-O-valeroate. However, similar reaction catalyzed by DMAP resulted 3,6-di-O-valeroate (21%) and 6-O-valeroate (47%) indicating reactivity sequence as 6-OH>3-OH>2-OH,4-OH. To get potential antimicrobial agents, 6-O-valeroate was converted into four 2,3,4-di-O-acyl esters, and 3,6-di-O-valeroate was converted into 2,4-di-O-acetate. Direct tetra-O-valeroylation of MDM gave a mixture of 2,3,4,6-tetra-O-valeroate and 2,3,6-tri-O-valeroate indicating that the C2-OH is more reactive than the equatorial C4-OH. The activity spectra analysis along with in vitro antimicrobial evaluation clearly indicated that these novel MDM esters had better antifungal activities over antibacterial agents. In this connection, molecular docking indicated that these MDM esters acted as competitive inhibitors of sterol 14α-demethylase (CYP51), an essential enzyme for clinical target to cure several infectious diseases. Furthermore, pharmacokinetic studies revealed that these MDM esters may be worth considering as potent candidates for oral and topical administration. Structure activity relationship (SAR) affirmed that saturated valeric chain (C5) in combination with caprylic (C8) chains was more promising CYP51 inhibitor over conventional antifungal antibiotics.


Asunto(s)
Inhibidores de 14 alfa Desmetilasa/farmacología , Inhibidores de 14 alfa Desmetilasa/farmacocinética , Ésteres/química , Manosa/farmacología , Manosa/farmacocinética , Simulación del Acoplamiento Molecular , Esterol 14-Desmetilasa/metabolismo , Inhibidores de 14 alfa Desmetilasa/síntesis química , Inhibidores de 14 alfa Desmetilasa/metabolismo , Células CACO-2 , Técnicas de Química Sintética , Humanos , Manosa/síntesis química , Manosa/metabolismo , Conformación Proteica , Esterol 14-Desmetilasa/química , Relación Estructura-Actividad
12.
Carbohydr Res ; 485: 107812, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31585251

RESUMEN

Octyl ß-d-glucopyranoside (OBG), prepared from d-glucose and octan-1-ol employing MW method, was subjected to direct dimolar valeroylation in pyridine at room temperature (25 °C) with valeroyl chloride. This mainly furnished the corresponding 3,6-di-O-valeroate in 57% yield indicating the regioselectivity at C-6 and C-3 positions. For structural elucidation and to get newer glucopyranosides of potential antimicrobial 3,6-di-O-valeroate was further converted into four novel 2,4-di-O-acyl esters reasonably in good yields. Per-O-acetate and per-O-benzoate of OBG were also prepared for SAR study. PASS predication and in vitro antimicrobial studies established them as better antifungal agent than that of antibacterial. SAR study along with AdmetSAR and SwissADME suggested that incorporation of alkanoyl and aromatic ester groups on octyl glucopyranoside core increase antimicrobial potentiality in very low concentration (10 µgmL-1). Molecular docking revealed that novel 2,4-di-O-tosyl ester and 2,3,4,6-tetra-O-benzoyl ester may act as competitive inhibitors of lanosterol 14-alpha demethylase.


Asunto(s)
Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Ésteres/química , Glucósidos/síntesis química , Glucósidos/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacocinética , Técnicas de Química Sintética , Glucósidos/química , Glucósidos/farmacocinética , Simulación del Acoplamiento Molecular , Conformación Proteica , Esterol 14-Desmetilasa/química , Esterol 14-Desmetilasa/metabolismo , Relación Estructura-Actividad
13.
Curr Protoc Immunol ; 123(1): e58, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30238640

RESUMEN

Proximity ligation assay (PLA), also referred to as Duolink® PLA technology, permits detection of protein-protein interactions in situ (at distances <40 nm) at endogenous protein levels. It exploits specific antibodies identifying (either directly or indirectly) the two proteins of interest and utilizes specific DNA primers covalently linked to the antibodies. A hybridization step followed by DNA amplification with fluorescent probes permit visualization of spots of proximity by fluorescence microscopy. Since the development of PLA in 2002, it has been increasingly used to detect the interaction between two proteins with high sensitivity and specificity. It is a simple and sensitive technique to study protein-protein interaction in cells. © 2018 by John Wiley & Sons, Inc.


Asunto(s)
Anticuerpos/química , Bioensayo/métodos , Cartilla de ADN/química , Mapeo de Interacción de Proteínas/métodos , Humanos , Microscopía Fluorescente/métodos
14.
J Biomol Screen ; 21(3): 277-89, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26538432

RESUMEN

Mitogen-activated protein kinase (MAPK) p38 is part of a broad and ubiquitously expressed family of MAPKs whose activity is responsible for mediating an intracellular response to extracellular stimuli through a phosphorylation cascade. p38 is central to this signaling node and is activated by upstream kinases while being responsible for activating downstream kinases and transcription factors via phosphorylation. Dysregulated p38 activity is associated with numerous autoimmune disorders and has been implicated in the progression of several types of cancer. A number of p38 inhibitors have been tested in clinical trials, with none receiving regulatory approval. One characteristic shared by all of the compounds that failed clinical trials is that they are all adenosine triphosphate (ATP)-competitive p38 inhibitors. Seeing this lack of mechanistic diversity as an opportunity, we screened ~32,000 substances in search of novel p38 inhibitors. Among the inhibitors discovered is a compound that is both non-ATP competitive and biologically active in cell-based models for p38 activity. This is the first reported discovery of a non-ATP-competitive p38 inhibitor that is active in cells and, as such, may enable new pharmacophore designs for both therapeutic and basic research to better understand and exploit non-ATP-competitive inhibitors of p38 activity.


Asunto(s)
Descubrimiento de Drogas/métodos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayos Analíticos de Alto Rendimiento , Humanos , Concentración 50 Inhibidora , Unión Proteica , Proteínas Recombinantes de Fusión , Bibliotecas de Moléculas Pequeñas , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
Nat Med ; 21(11): 1337-43, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26479921

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive neoplasm characterized by a marked fibro-inflammatory microenvironment, the presence of which can promote both cancer induction and growth. Therefore, selective manipulation of local cytokines is an attractive, although unrealized, therapeutic approach. T cells possess a unique mechanism of p38 mitogen-activated protein kinase (MAPK) activation downstream of T cell receptor (TCR) engagement through the phosphorylation of Tyr323 (pY323). This alternative p38 activation pathway is required for pro-inflammatory cytokine production. Here we show in human PDAC that a high percentage of infiltrating pY323(+) T cells was associated with large numbers of tumor necrosis factor (TNF)-α- and interleukin (IL)-17-producing CD4(+) tumor-infiltrating lymphocytes (TILs) and aggressive disease. The growth of mouse pancreatic tumors was inhibited by genetic ablation of the alternative p38 pathway, and transfer of wild-type CD4(+) T cells, but not those lacking the alternative pathway, enhanced tumor growth in T cell-deficient mice. Notably, a plasma membrane-permeable peptide derived from GADD45-α, the naturally occurring inhibitor of p38 pY323(+) (ref. 7), reduced CD4(+) TIL production of TNF-α, IL-17A, IL-10 and secondary cytokines, halted growth of implanted tumors and inhibited progression of spontaneous KRAS-driven adenocarcinoma in mice. Thus, TCR-mediated activation of CD4(+) TILs results in alternative p38 activation and production of protumorigenic factors and can be targeted for therapeutic benefit.


Asunto(s)
Carcinoma Ductal Pancreático/inmunología , Citocinas/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias Pancreáticas/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología , Animales , Linfocitos T CD4-Positivos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Línea Celular Tumoral , Citocinas/metabolismo , Progresión de la Enfermedad , Humanos , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-17/inmunología , Interleucina-17/metabolismo , Linfocitos Infiltrantes de Tumor/metabolismo , Sistema de Señalización de MAP Quinasas/genética , Sistema de Señalización de MAP Quinasas/inmunología , Ratones , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosforilación , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética
16.
J Exp Med ; 211(6): 1257-70, 2014 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-24863062

RESUMEN

Unlike the MAP kinase (MAPK) cascade that phosphorylates p38 on the activation loop, T cell receptor (TCR) signaling results in phosphorylation on Tyr-323 (pY323, alternative pathway). Using mice expressing p38α and p38ß with Y323F substitutions, we show that alternatively but not MAPK cascade-activated p38 up-regulates the transcription factors NFATc1 and IRF4, which are required for proliferation and cytokine production. Conversely, activation of p38 with UV or osmotic shock mitigated TCR-mediated activation by phosphorylation and cytoplasmic retention of NFATc1. Notably, UVB treatment of human psoriatic lesions reduced skin-infiltrating p38 pY323(+) T cell IRF4 and IL-17 production. Thus, distinct mechanisms of p38 activation converge on NFATc1 with opposing effects on T cell immunity, which may underlie the beneficial effect of phototherapy on psoriasis.


Asunto(s)
Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Activación Enzimática , Femenino , Técnicas de Sustitución del Gen , Humanos , Immunoblotting , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/inmunología , Factores Reguladores del Interferón/metabolismo , Interleucina-17/inmunología , Interleucina-17/metabolismo , Isoenzimas/genética , Isoenzimas/inmunología , Isoenzimas/metabolismo , Activación de Linfocitos/inmunología , Activación de Linfocitos/efectos de la radiación , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/inmunología , Factores de Transcripción NFATC/metabolismo , Psoriasis/inmunología , Psoriasis/metabolismo , Psoriasis/radioterapia , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Piel/inmunología , Piel/metabolismo , Piel/efectos de la radiación , Células Th17/inmunología , Células Th17/metabolismo , Tirosina/metabolismo , Rayos Ultravioleta , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/genética
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda