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2.
Nature ; 583(7818): 807-812, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669708

RESUMEN

The majority of targeted therapies for non-small-cell lung cancer (NSCLC) are directed against oncogenic drivers that are more prevalent in patients with light exposure to tobacco smoke1-3. As this group represents around 20% of all patients with lung cancer, the discovery of stratified medicine options for tobacco-associated NSCLC is a high priority. Umbrella trials seek to streamline the investigation of genotype-based treatments by screening tumours for multiple genomic alterations and triaging patients to one of several genotype-matched therapeutic agents. Here we report the current outcomes of 19 drug-biomarker cohorts from the ongoing National Lung Matrix Trial, the largest umbrella trial in NSCLC. We use next-generation sequencing to match patients to appropriate targeted therapies on the basis of their tumour genotype. The Bayesian trial design enables outcome data from open cohorts that are still recruiting to be reported alongside data from closed cohorts. Of the 5,467 patients that were screened, 2,007 were molecularly eligible for entry into the trial, and 302 entered the trial to receive genotype-matched therapy-including 14 that re-registered to the trial for a sequential trial drug. Despite pre-clinical data supporting the drug-biomarker combinations, current evidence shows that a limited number of combinations demonstrate clinically relevant benefits, which remain concentrated in patients with lung cancers that are associated with minimal exposure to tobacco smoke.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/terapia , Marcadores Genéticos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Terapia Molecular Dirigida , Medicina de Precisión , Fumar/genética , Teorema de Bayes , Carcinoma de Pulmón de Células no Pequeñas/etiología , Protocolos Clínicos , Ensayos Clínicos como Asunto , Estudios de Cohortes , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Pulmonares/etiología , Oncogenes/genética , Selección de Paciente , Humo/efectos adversos , Triaje
3.
PLoS Pathog ; 19(10): e1011717, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37878666

RESUMEN

A protective HIV-1 vaccine has been hampered by a limited understanding of how B cells acquire neutralizing activity. Our previous vaccines expressing two different HIV-1 envelopes elicited robust antigen specific serum IgG titers in 20 rhesus macaques; yet serum from only two animals neutralized the autologous virus. Here, we used high throughput immunoglobulin receptor and single cell RNA sequencing to characterize the overall expansion, recall, and maturation of antigen specific B cells longitudinally over 90 weeks. Diversification and expansion of many B cell clonotypes occurred broadly in the absence of serum neutralization. However, in one animal that developed neutralization, two neutralizing B cell clonotypes arose from the same immunoglobulin germline and were tracked longitudinally. Early antibody variants with high identity to germline neutralized the autologous virus while later variants acquired somatic hypermutation and increased neutralization potency. The early engagement of precursors capable of neutralization with little to no SHM followed by prolonged affinity maturation allowed the two neutralizing lineages to successfully persist despite many other antigen specific B cells. The findings provide new insight into B cells responding to HIV-1 envelope during heterologous prime and boost immunization in rhesus macaques and the development of selected autologous neutralizing antibody lineages.


Asunto(s)
Vacunas contra el SIDA , Infecciones por VIH , Seropositividad para VIH , VIH-1 , Animales , Anticuerpos Neutralizantes , Macaca mulatta , Anticuerpos Anti-VIH , Inmunización , Productos del Gen env del Virus de la Inmunodeficiencia Humana
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37685922

RESUMEN

HTLV-1 is an oncogenic human retrovirus and the etiologic agent of the highly aggressive ATL malignancy. Two viral genes, Tax and Hbz, are individually linked to oncogenic transformation and play an important role in the pathogenic process. Consequently, regulation of HTLV-1 gene expression is a central feature in the viral lifecycle and directly contributes to its pathogenic potential. Herein, we identified the cellular transcription factor YBX1 as a binding partner for HBZ. We found YBX1 activated transcription and enhanced Tax-mediated transcription from the viral 5' LTR promoter. Interestingly, YBX1 also interacted with Tax. shRNA-mediated loss of YBX1 decreased transcript and protein abundance of both Tax and HBZ in HTLV-1-transformed T-cell lines, as well as Tax association with the 5' LTR. Conversely, YBX1 transcriptional activation of the 5' LTR promoter was increased in the absence of HBZ. YBX1 was found to be associated with both the 5' and 3' LTRs in HTLV-1-transformed and ATL-derived T-cell lines. Together, these data suggest that YBX1 positively influences transcription from both the 5' and 3' promoter elements. YBX1 is able to interact with Tax and help recruit Tax to the 5' LTR. However, through interactions with HBZ, YBX1 transcriptional activation of the 5' LTR is repressed.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Proteína 1 de Unión a la Caja Y , Humanos , Genes Virales , Virus Linfotrópico T Tipo 1 Humano/genética , Regiones Promotoras Genéticas , ARN Interferente Pequeño , Secuencias Repetidas Terminales/genética , Proteína 1 de Unión a la Caja Y/genética
5.
J Infect Dis ; 225(9): 1632-1641, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-34331451

RESUMEN

BACKGROUND: Diagnosis of paucibacillary tuberculosis (TB) including extrapulmonary TB is a significant challenge, particularly in high-income, low-incidence settings. Measurement of Mycobacterium tuberculosis (Mtb)-specific cellular immune signatures by flow cytometry discriminates active TB from latent TB infection (LTBI) in case-control studies; however, their diagnostic accuracy and clinical utility in routine clinical practice is unknown. METHODS: Using a nested case-control study design within a prospective multicenter cohort of patients presenting with suspected TB in England, we assessed diagnostic accuracy of signatures in 134 patients who tested interferon-gamma release assay (IGRA)-positive and had final diagnoses of TB or non-TB diseases with coincident LTBI. Cellular signatures were measured using flow cytometry. RESULTS: All signatures performed less well than previously reported. Only signatures incorporating measurement of phenotypic markers on functional Mtb-specific CD4 T cells discriminated active TB from non-TB diseases with LTBI. The signatures measuring HLA-DR+IFNγ + CD4 T cells and CD45RA-CCR7-CD127- IFNγ -IL-2-TNFα + CD4 T cells performed best with 95% positive predictive value (95% confidence interval, 90-97) in the clinically challenging subpopulation of IGRA-positive but acid-fast bacillus (AFB) smear-negative TB suspects. CONCLUSIONS: Two cellular immune signatures could improve and accelerate diagnosis in the challenging group of patients who are IGRA-positive, AFB smear-negative, and have paucibacillary TB.


Asunto(s)
Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis , Estudios de Casos y Controles , Humanos , Ensayos de Liberación de Interferón gamma , Tuberculosis Latente/diagnóstico , Estudios Prospectivos , Tuberculosis/diagnóstico
6.
Scand J Immunol ; 96(5)2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37406035

RESUMEN

CpG Oligodeoxynucleotides (ODNs) are established TLR9 ligands; however, their functional responses in CD4+ T cells are believed to be independent of TLR9 and MyD88. We studied ligand-receptor interactions of ODN 2216 and TLR9 in human CD4+ T cells and assessed their consequences in terms of TLR9 signalling and cell phenotype. We demonstrated that the uptake of ODN 2216, a synthetic TLR9 agonist, is controlled by TLR9 signalling molecules and results in an increase in the expression of TLR9 signalling molecules, regulated via a feedback mechanism. Next, the uptake of ODN 2216 resulted in TLR9 signalling dependent but MyD88 independent increase in expression of TGF-ß. Finally, ODN 2216 treated CD4+ T cells showed an anti-inflammatory phenotype that was similar to Th3 type of regulatory T cells. These Th3-like cells were able to suppress the proliferation of untreated CD4+ T cells. Collectively, our results demonstrate a direct and interdependent relationship between ODN 2216 uptake and TLR9 signalling in CD4+ T cells. Our findings thus pave the way for future research to explore direct modulation of adaptive immune cells, using innate immune ligands, to subvert exaggerated inflammatory responses.


Asunto(s)
Factor 88 de Diferenciación Mieloide , Receptor Toll-Like 9 , Humanos , Receptor Toll-Like 9/genética , Ligandos , Factor 88 de Diferenciación Mieloide/metabolismo , Linfocitos T CD4-Positivos , Transducción de Señal , Oligodesoxirribonucleótidos/farmacología , Oligodesoxirribonucleótidos/genética
7.
Haematologica ; 107(12): 2928-2943, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-35615924

RESUMEN

Adult T-cell leukemia and lymphoma (ATLL) is an intractable T-cell neoplasia caused by a retrovirus, namely human T-cell leukemia virus type 1 (HTLV-1). Patients suffering from ATLL present a poor prognosis and have a dearth of treatment options. In contrast to the sporadic expression of viral transactivator protein Tax present at the 5' promoter region long terminal repeats (LTR), HTLV-1 bZIP gene (HBZ) is encoded by 3'LTR (the antisense promoter) and maintains its constant expression in ATLL cells and patients. The antisense promoter is associated with selective retroviral gene expression and has been an understudied phenomenon. Herein, we delineate the activity of transcription factor MEF (myocyte enhancer factor)-2 family members, which were found to be enriched at the 3'LTR and play an important role in the pathogenesis of ATLL. Of the four MEF isoforms (A to D), MEF-2A and 2C were highly overexpressed in a wide array of ATLL cell lines and in acute ATLL patients. The activity of MEF-2 isoforms were determined by knockdown experiments that led to decreased cell proliferation and regulated cell cycle progression. High enrichment of MEF-2C was observed at the 3'LTR along with cofactors Menin and JunD resulting in binding of MEF-2C to HBZ at this region. Chemical inhibition of MEF-2 proteins resulted in the cytotoxicity of ATLL cells in vitro and reduction of proviral load in a humanized mouse model. Taken together, this study provides a novel mechanism of 3'LTR regulation and establishes MEF-2 signaling a potential target for therapeutic intervention for ATLL.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T del Adulto , Linfoma , Animales , Humanos , Ratones , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/metabolismo , Leucemia-Linfoma de Células T del Adulto/patología , Linfoma/genética , Factores de Transcripción MEF2/genética , Factores de Transcripción MEF2/metabolismo , Regiones Promotoras Genéticas , Proteínas Virales/genética , Proteínas Virales/metabolismo
8.
J Org Chem ; 87(19): 12547-12557, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584056

RESUMEN

A thorough DFT study was performed to unravel the true mechanism involved in the Pd(0)-catalyzed functional group transposition between aroyl chlorides and aryl iodides. Two different experimental groups proposed different mechanisms for the functional group transposition reaction. A careful assessment of experimental findings and thorough computational studies endorsed that the functional group transposition proceeds via phosphonium salt formation and ligand-enabled C-P bond metathesis, leading to the formation of the PhI and the intermediate 2. After the formation of the intermediate 2, the transposition of functional groups takes place through the interpalladium ligand exchange mechanism, where two palladium centers act as shuttle catalysts. In short, both C-P bond metathesis and interpalladium ligand exchange steps are crucial in the functional group transposition mechanism.

9.
Saudi Pharm J ; 30(7): 879-905, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35645588

RESUMEN

The SARS-CoV-2 (COVID 19) paroxysm is a dominant health exigency that caused significant distress, affecting physical and mental health. Increased mortality, a stressed healthcare system, financial crisis, isolation, and new living and working styles enhanced societal commiseration leading to poor health outcomes. Though people try to maintain good physical health but unfortunately the mental affliction is still ignored. Poor psychological health has emerged as a burgeoning social issue and demands attention. Henceforth, the fundamental objective of this review article is to collate information about COVID-linked physical and psychological agony in diverse population groups with related symptoms and accessible diagnosis techniques. Recent studies have unraveled the fragile mental states of people who have either contracted COVID 19 or had near and dear ones falling prey to it. The impact of the epidemic on the human mind both in short and long-term, with possible risk and preventive factors together with suggested solutions for maintaining good health have also been discussed here. It also enlists the available medications, vaccines and investigational research in the form of patents and clinical trials. This article can be taken as an updated information sheet for COVID 19, accompanied by its management techniques with special emphasis on coping strategies for mental health. Further, it may also assist the policymakers to devise approaches that could enable the public to overcome the pandemic-driven adversity not only in the given situation but also futuristically.

10.
Eur J Neurosci ; 53(2): 637-648, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33169893

RESUMEN

One of the key knowledge gaps in the field of Alzheimer's disease research is the lack of understanding of how amyloid beta and tau cooperate to cause neurodegeneration. We recently generated a mouse model (APP/PS1 + Tau) that develops amyloid plaque pathology and expresses human tau in the absence of endogenous murine tau. These mice exhibit an age-related behavioural hyperactivity phenotype and transcriptional deficits which are ameliorated by tau transgene suppression. We hypothesized that these mice would also display memory and hippocampal synaptic plasticity deficits as has been reported for many plaque bearing mouse models which express endogenous mouse tau. We observed that our APP/PS1 + Tau model does not exhibit novel object memory or robust long-term potentiation deficits with age, whereas the parent APP/PS1 line with mouse tau did develop the expected deficits. These data are important as they highlight potential functional differences between mouse and human tau and the need to use multiple models to fully understand Alzheimer's disease pathogenesis and develop effective therapeutic strategies.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Animales , Modelos Animales de Enfermedad , Humanos , Potenciación a Largo Plazo , Ratones , Ratones Transgénicos , Placa Amiloide , Presenilina-1 , Proteínas tau/genética
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