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1.
Nat Immunol ; 21(3): 287-297, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31932812

RESUMEN

Cancer cells subvert immune surveillance through inhibition of T cell effector function. Elucidation of the mechanism of T cell dysfunction is therefore central to cancer immunotherapy. Here, we report that dual specificity phosphatase 2 (DUSP2; also known as phosphatase of activated cells 1, PAC1) acts as an immune checkpoint in T cell antitumor immunity. PAC1 is selectively upregulated in exhausted tumor-infiltrating lymphocytes and is associated with poor prognosis of patients with cancer. PAC1hi effector T cells lose their proliferative and effector capacities and convert into exhausted T cells. Deletion of PAC1 enhances immune responses and reduces cancer susceptibility in mice. Through activation of EGR1, excessive reactive oxygen species in the tumor microenvironment induce expression of PAC1, which recruits the Mi-2ß nucleosome-remodeling and histone-deacetylase complex, eventually leading to chromatin remodeling of effector T cells. Our study demonstrates that PAC1 is an epigenetic immune regulator and highlights the importance of targeting PAC1 in cancer immunotherapy.


Asunto(s)
Fosfatasa 2 de Especificidad Dual/inmunología , Neoplasias/inmunología , Linfocitos T/inmunología , Animales , Cromatina/genética , Cromatina/metabolismo , Fosfatasa 2 de Especificidad Dual/deficiencia , Fosfatasa 2 de Especificidad Dual/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Femenino , Humanos , Activación de Linfocitos , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Neoplasias/genética , Neoplasias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Regulación hacia Arriba
2.
Mol Cell ; 76(1): 110-125.e9, 2019 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-31474573

RESUMEN

Failure to make adaptive immune responses is a hallmark of aging. Reduced B cell function leads to poor vaccination efficacy and a high prevalence of infections in the elderly. Here we show that reduced autophagy is a central molecular mechanism underlying immune senescence. Autophagy levels are specifically reduced in mature lymphocytes, leading to compromised memory B cell responses in old individuals. Spermidine, an endogenous polyamine metabolite, induces autophagy in vivo and rejuvenates memory B cell responses. Mechanistically, spermidine post-translationally modifies the translation factor eIF5A, which is essential for the synthesis of the autophagy transcription factor TFEB. Spermidine is depleted in the elderly, leading to reduced TFEB expression and autophagy. Spermidine supplementation restored this pathway and improved the responses of old human B cells. Taken together, our results reveal an unexpected autophagy regulatory mechanism mediated by eIF5A at the translational level, which can be harnessed to reverse immune senescence in humans.


Asunto(s)
Autofagia/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Senescencia Celular/efectos de los fármacos , Inmunosenescencia/efectos de los fármacos , Factores de Iniciación de Péptidos/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas de Unión al ARN/metabolismo , Espermidina/farmacología , Inmunidad Adaptativa/efectos de los fármacos , Factores de Edad , Envejecimiento , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/patología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/deficiencia , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Células HEK293 , Humanos , Memoria Inmunológica/efectos de los fármacos , Células Jurkat , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células 3T3 NIH , Factores de Iniciación de Péptidos/genética , Proteínas de Unión al ARN/genética , Transducción de Señal , Factor 5A Eucariótico de Iniciación de Traducción
3.
Nat Chem Biol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773328

RESUMEN

A timely inflammatory response is crucial for early viral defense, but uncontrolled inflammation harms the host. Retinoic acid-inducible gene I (RIG-I) has a pivotal role in detecting RNA viruses, yet the regulatory mechanisms governing its sensitivity remain elusive. Here we identify PTENα, an N-terminally extended form of PTEN, as an RNA-binding protein with a preference for the CAUC(G/U)UCAU motif. Using both in vivo and in vitro viral infection assays, we demonstrated that PTENα restricted the host innate immune response, relying on its RNA-binding capacity and phosphatase activity. Mechanistically, PTENα directly bound to viral RNA and enzymatically converted its 5'-triphosphate to 5'-monophosphate, thereby reducing RIG-I sensitivity. Physiologically, brain-intrinsic PTENα exerted protective effects against viral inflammation, while peripheral PTENα restricted host antiviral immunity and, to some extent, promoted viral replication. Collectively, our findings underscore the significance of PTENα in modulating viral RNA- and RIG-I-mediated immune recognition, offering potential therapeutic implications for infectious diseases.

4.
Chem Rec ; 19(8): 1729-1752, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30698895

RESUMEN

The unique features of solution-processed quantum dots (QDs) including emission tunability in the visible range, high-quality saturated color and outstanding intrinsic stability in environment are highly desired in various application fields. Especially, for the preparation of wide color gamut displays, QDs with high photoluminescence quantum yield are deemed as the optimal fluorescent emitter that has been utilized in the backlight for liquid crystal display. Nevertheless, the commercialization of electrically driven self-emissive quantum dot light-emitting diode (QLED) display is the ultimate target due to its merits of high contrast, slim configuration and compatibility with flexible substrate. Through the great efforts devoted to material engineering and device configuration, astonishing progresses have been made in device performance, giving the QLED technology a great chance to compete with other counterparts for next-generation displays. In this review, we retrospect the development roadmap of QLED technology and introduce the essential principles in the QLED devices. Moreover, we discuss the key factors that affect the QLED efficiency and lifetime. Finally, the advances in device architectures and pixel patterning are also summarized.

5.
J Nat Prod ; 82(5): 1274-1282, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-30978020

RESUMEN

Three new compounds (9-11) were isolated together with eight known analogues from the fungus Pseudallescheria boydii associated with the South China Sea soft coral Sinularia sandensis. The structures of the new compounds were elucidated on the basis of the spectroscopic analysis, and the absolute configurations including the sulfur stereogenic center of a sulfoxide moiety were determined by comparison of experimental ECD spectra to TDDFT/ECD calculations. Epimeric chiral sulfoxides differing in the absolute configuration of the sulfur chirality center could be efficiently distinguished and assigned by comparing the experimental ECD to those of calculations for the sulfur epimers. In the in vitro biotests for osteoclastogenesis effects, compounds 1, 5, 7, and 10 exhibited a stimulatory activity, while compound 3 displayed an inhibitory activity.


Asunto(s)
Antozoos/microbiología , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Pseudallescheria/química , Animales , Biología Computacional , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Estereoisomerismo , Óxidos de Azufre/química
6.
J Autoimmun ; 94: 156-165, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30100102

RESUMEN

Dysregulation of innate immunity accompanied by excessive interferon production contributes to autoimmune disease. However, the mechanism by which the immune response is modulated in autoimmune disorders is largely unknown. Here we identified loss-of-function mutations of OTUD1 associated with multiple autoimmune diseases. Under inflammatory conditions, inducible OTUD1 acts as an immune checkpoint and blocks RIG-I-like receptors signaling. As a deubiquitinase, OTUD1 directly interacts with transcription factor IRF3 and removes the K63-linked poly-ubiquitin chains on IRF3 Lysine 98, which inhibits IRF3 nuclear translocation and transcriptional activity. In contrast, OTUD1 mutants impair its suppressive effects on IRF3 via attenuating the OTUD1 deubiquinase activity or its association with IRF3. Moreover, we found FOXO3 signaling is required for OTUD1 induction upon antigenic stimulation. Our data demonstrate that OTUD1 is involved in maintaining immune homeostasis and loss-of-function mutations of OTUD1 enhance the immune response and are associated with autoimmunity.


Asunto(s)
Artritis Reumatoide/genética , Colitis Ulcerosa/genética , Enfermedad de Hashimoto/genética , Lupus Eritematoso Sistémico/genética , Linfocitos/inmunología , Proteasas Ubiquitina-Específicas/genética , Adulto , Secuencia de Aminoácidos , Artritis Reumatoide/inmunología , Artritis Reumatoide/patología , Estudios de Casos y Controles , Línea Celular Tumoral , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Proteína 58 DEAD Box/genética , Proteína 58 DEAD Box/inmunología , Femenino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/inmunología , Regulación de la Expresión Génica , Células HEK293 , Enfermedad de Hashimoto/inmunología , Enfermedad de Hashimoto/patología , Homeostasis/inmunología , Humanos , Factor 3 Regulador del Interferón/genética , Factor 3 Regulador del Interferón/inmunología , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/patología , Linfocitos/patología , Masculino , Mutación , Transporte de Proteínas , Receptores Inmunológicos , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transducción de Señal , Proteasas Ubiquitina-Específicas/inmunología
7.
Pharmazie ; 73(7): 402-407, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30001775

RESUMEN

OBJECTIVE: Curcumin has been reported to possess anti-tumor effects on multiple cancers, including lung cancer. However, the mechanisms of its anti-tumor effect on lung cancer have not been fully elucidated. Our study attempted to identify the effect of curcumin on A549 cells and further explore the potential mechanism. METHODS: Different concentrations of curcumin were exposed to A549 cells for 24 h and cell viability was measured by CCK-8 assay. The expression of UCA1 was overexpressed in A549 cells by transfection with pEX-UCA1. Cell proliferation was determined by BrdU staining and assessing the expression of CyclinD1 using western blot and RT-PCR assay. Apoptotic cells were measured by flow cytometry assay. Western blot was performed to assess the expression of apoptosis-related, Wnt and mTOR pathways-related factors. RESULTS: Curcumin incubation dramatically reduced viability of A549 cells in a dosage-dependent manner. Curcumin (0.6 µM) significantly reduced BrdU+-positive cells, declined the expression of CyclinD1, and enhanced cell apoptosis. Interestingly, we found that curcumin inhibited the expression of UCA1 and UCA1 overexpression abolished the effect of curcumin on cell apoptosis. In addition, we also found that curcumin inhibited Wnt and mTOR pathways through down-regulation of UCA1. CONCLUSION: We demonstrated that curcumin inhibited the growth of A549 cells through downregulation of UCA1, which might provide new insight for the treatment of lung cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Curcumina/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , ARN Largo no Codificante/genética , Células A549 , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Western Blotting , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Curcumina/administración & dosificación , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serina-Treonina Quinasas TOR/metabolismo , Vía de Señalización Wnt/efectos de los fármacos
8.
J Nat Prod ; 80(11): 2930-2940, 2017 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-29048894

RESUMEN

Fourteen new polyketides with a trans-fused decalin ring system, libertalides A-N (3-16), together with two known analogues, aspermytin A and its acetate (1, 2), were isolated from the fermentation extract of a coral-derived Libertasomyces sp. fungus. Their relative configurations were elucidated on the basis of detailed spectroscopic analysis, and the absolute configurations were determined by TDDFT-ECD and optical rotation (OR) calculations. The OR of 1 and 2 were found to have opposite signs in CH3CN and CHCl3, which was in agreement with the OR calculations producing alternating signs for the optical rotation depending on the applied conditions. Because the signs of the OR for 1 and 2 showed high solvent dependence, they may not be used alone to correlate the absolute configurations. Compound 16 displayed structural novelty characterized by an α-enol ether bridge conjugated with an aldehyde group. In in vitro immunomodulatory screening, compounds 1, 4, and 10 significantly induced the proliferation of CD3+ T cells, while compounds 2, 7, 11, and 14 significantly increased the CD4+/CD8+ ratio at 3 µM. A preliminary structure-activity analysis revealed a crucial role of Δ7 and a terminal OH group in the regulation of CD3+ T cell proliferation. This is the first report of immunoregulatory activity for metabolites of this kind.


Asunto(s)
Antozoos/microbiología , Factores Inmunológicos/aislamiento & purificación , Factores Inmunológicos/farmacología , Policétidos/aislamiento & purificación , Policétidos/farmacología , Animales , Ascomicetos/efectos de los fármacos , Cristalografía por Rayos X , Factores Inmunológicos/química , Biología Marina , Hongos Mitospóricos , Estructura Molecular , Naftalenos , Resonancia Magnética Nuclear Biomolecular , Penicillium/química , Policétidos/química
9.
Nat Commun ; 15(1): 4481, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802397

RESUMEN

Retinal degeneration, a leading cause of irreversible low vision and blindness globally, can be partially addressed by retina prostheses which stimulate remaining neurons in the retina. However, existing electrode-based treatments are invasive, posing substantial risks to patients and healthcare providers. Here, we introduce a completely noninvasive ultrasonic retina prosthesis, featuring a customized ultrasound two-dimensional array which allows for simultaneous imaging and stimulation. With synchronous three-dimensional imaging guidance and auto-alignment technology, ultrasonic retina prosthesis can generate programmed ultrasound waves to dynamically and precisely form arbitrary wave patterns on the retina. Neuron responses in the brain's visual center mirrored these patterns, evidencing successful artificial vision creation, which was further corroborated in behavior experiments. Quantitative analysis of the spatial-temporal resolution and field of view demonstrated advanced performance of ultrasonic retina prosthesis and elucidated the biophysical mechanism of retinal stimulation. As a noninvasive blindness prosthesis, ultrasonic retina prosthesis could lead to a more effective, widely acceptable treatment for blind patients. Its real-time imaging-guided stimulation strategy with a single ultrasound array, could also benefit ultrasound neurostimulation in other diseases.


Asunto(s)
Ceguera , Retina , Prótesis Visuales , Retina/diagnóstico por imagen , Retina/fisiología , Animales , Ceguera/terapia , Ceguera/fisiopatología , Degeneración Retiniana/terapia , Degeneración Retiniana/diagnóstico por imagen , Ondas Ultrasónicas , Humanos , Neuronas/fisiología , Ultrasonografía/métodos , Visión Ocular/fisiología
10.
Nat Nanotechnol ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684808

RESUMEN

Ferrotoroidicity-the fourth form of primary ferroic order-breaks both space and time-inversion symmetry. So far, direct observation of ferrotoroidicity in natural materials remains elusive, which impedes the exploration of ferrotoroidic phase transitions. Here we overcome the limitations of natural materials using an artificial nanomagnet system that can be characterized at the constituent level and at different effective temperatures. We design a nanomagnet array as to realize a direct-kagome spin ice. This artificial spin ice exhibits robust toroidal moments and a quasi-degenerate ground state with two distinct low-temperature toroidal phases: ferrotoroidicity and paratoroidicity. Using magnetic force microscopy and Monte Carlo simulation, we demonstrate a phase transition between ferrotoroidicity and paratoroidicity, along with a cross-over to a non-toroidal paramagnetic phase. Our quasi-degenerate artificial spin ice in a direct-kagome structure provides a model system for the investigation of magnetic states and phase transitions that are inaccessible in natural materials.

11.
Nat Commun ; 15(1): 3837, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714665

RESUMEN

Although metabolic reprogramming within tumor cells and tumor microenvironment (TME) is well described in breast cancer, little is known about how the interplay of immune state and cancer metabolism evolves during treatment. Here, we characterize the immunometabolic profiles of tumor tissue samples longitudinally collected from individuals with breast cancer before, during and after neoadjuvant chemotherapy (NAC) using proteomics, genomics and histopathology. We show that the pre-, on-treatment and dynamic changes of the immune state, tumor metabolic proteins and tumor cell gene expression profiling-based metabolic phenotype are associated with treatment response. Single-cell/nucleus RNA sequencing revealed distinct tumor and immune cell states in metabolism between cold and hot tumors. Potential drivers of NAC based on above analyses were validated in vitro. In summary, the study shows that the interaction of tumor-intrinsic metabolic states and TME is associated with treatment outcome, supporting the concept of targeting tumor metabolism for immunoregulation.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Microambiente Tumoral , Humanos , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Microambiente Tumoral/inmunología , Regulación Neoplásica de la Expresión Génica , Perfilación de la Expresión Génica , Estudios Longitudinales , Persona de Mediana Edad , Proteómica , Adulto , Línea Celular Tumoral , Análisis de la Célula Individual
12.
Front Immunol ; 14: 1230718, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37809084

RESUMEN

Introduction: Human cytomegalovirus (HCMV) reactivation causes complications in immunocompromised patients after hematopoietic stem cell transplantation (HSCT), significantly increasing morbidity and mortality. Adaptive Natural Killer (aNK) cells undergo a persistent reconfiguration in response to HCMV reactivation; however, the exact role of aNK cell memory in HCMV surveillance remains elusive. Methods: We employed mass spectrometry and computational prediction approaches to identify HLA-E-restricted HCMV peptides that can elucidate aNK cell responses. We also used the K562 cell line transfected with HLA-E0*0103 for specific peptide binding and blocking assays. Subsequently, NK cells were cocultured with dendritic cells (DCs) loaded with each of the identified peptides to examine aNK and conventional (c)NK cell responses. Results: Here, we discovered three unconventional HLA-E-restricted 15-mer peptides (SEVENVSVNVHNPTG, TSGSDSDEELVTTER, and DSDEELVTTERKTPR) derived from the HCMV pp65-protein that elicit aNK cell memory responses restricted to HCMV. aNK cells displayed memory responses towards HMCV-infected cells and HCMV-seropositive individuals when primed by DCs loaded with each of these peptides and predicted 9-mer versions. Blocking the interaction between HLA-E and the activation NKG2C receptor but not the inhibitory NKG2A receptor abolished these specific recall responses. Interestingly, compared to the HLA-E complex with the leader peptide VMAPRTLIL, HLA-E complexes formed with each of the three identified peptides significantly changed the surface electrostatic potential to highly negative. Furthermore, these peptides do not comprise the classical HLA-E-restriction motifs. Discussion: These findings suggest a differential binding to NKG2C compared to HLA-E complexes with classical leader peptides that may result in the specific activation of aNK cells. We then designed six nonameric peptides based on the three discovered peptides that could elicit aNK cell memory responses to HCMV necessary for therapeutic inventions. The results provide novel insights into HLA-E-mediated signaling networks that mediate aNK cell recall responses and maximize their reactivity.


Asunto(s)
Infecciones por Citomegalovirus , Humanos , Antígenos de Histocompatibilidad Clase I/metabolismo , Citomegalovirus/metabolismo , Células Asesinas Naturales , Péptidos/química , Antígenos HLA-E
13.
Neurochem Res ; 37(4): 732-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22147284

RESUMEN

There is evidence from immunohistochemistry, quantitative microchemistry, and pharmacology for several amino acids as neurotransmitters in the vestibular nuclear complex (VNC), including glutamate, γ-aminobutyrate (GABA), and glycine. However, evidence from measurements of release has been limited. The purpose of this study was to measure depolarization-stimulated calcium-dependent release of amino acids from the VNC in brain slices. Coronal slices containing predominantly the VNC were prepared from rats and perfused with artificial cerebrospinal fluid (ACSF) in an interface chamber. Fluid was collected from the chamber just downstream from the VNC using a microsiphon. Depolarization was induced by 50 mM potassium in either control calcium and magnesium concentrations or reduced calcium and elevated magnesium. Amino acid concentrations in effluent fluid were measured by high performance liquid chromatography. Glutamate release increased fivefold during depolarization in control calcium concentration and twofold in low calcium/high magnesium. These same ratios were 6 and 1.5 for GABA, 2 and 1.3 for glycine, and 2 and 1.5 for aspartate. Differences between release in control and low calcium/high magnesium ACSF were statistically significant for glutamate, GABA, and glycine. Glutamine release decreased during and after depolarization, and taurine release slowly increased. No evidence for calcium-dependent release was found for serine, glutamine, alanine, threonine, arginine, taurine, or tyrosine. Our results support glutamate and GABA as major neurotransmitters in the VNC. They also support glycine as a neurotransmitter and some function for taurine.


Asunto(s)
Aminoácidos/metabolismo , Polaridad Celular , Sinapsis/metabolismo , Núcleos Vestibulares/metabolismo , Animales , Polaridad Celular/fisiología , Masculino , Técnicas de Cultivo de Órganos , Cloruro de Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Sinapsis/efectos de los fármacos , Núcleos Vestibulares/efectos de los fármacos
14.
Clin Transl Immunology ; 11(9): e1419, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36188121

RESUMEN

Objectives: Although adoptive cell therapy with T-cell receptor-engineered T cells (TCR-Ts) has mediated effective antitumor responses in several cancers, senescence of T cells could impair the therapeutic effect of TCR-Ts. Thus, it is essential to elucidate the characteristics of senescent TCR-Ts and how to subsequently improve their antitumor effect. Here, we focused on the influence of autophagy on TCR-Ts, since autophagy is tightly associated with the regulation of T-cell activation, proliferation and differentiation. Methods: We first evaluated autophagy level of senescent TCR-Ts, and then the senescent TCR-Ts were expanded in vitro for 7 days with and without spermidine treatment, respectively. Furthermore, the proliferative potential, phenotypical characteristics and functionality of the propagated senescent TCR-Ts were analysed in vitro and in vivo after 7-day ex vivo expansion. Results: We found that autophagic flux of senescent TCR-T cells was significantly impaired. The restoration of autophagic flux via spermidine treatment reduced the expression of inhibitory immunoreceptors (PD-1, TIM-3 or LAG-3), enhanced proliferation and effector functions and subsequently demonstrated the superior in vitro and in vivo antitumor activity of TCR-Ts. Conclusion: These data suggest that spermidine treatment presents an opportunity to improve the antitumor effect of TCR-Ts for the treatment of solid tumors.

15.
J Immunother Cancer ; 10(10)2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36307150

RESUMEN

BACKGROUND: Although adoptive cell therapy with tumor infiltrating lymphocytes (TILs) has mediated effective antitumor responses in several cancers, dysfunction and exhaustion of TILs significantly impair the therapeutic effect of TILs. Thus, it is essential to elucidate the exhausted characteristics of TILs and improve the antitumor effect of TILs by reversing their exhaustion. Here, we focused on the influence of autophagy on TILs in terms of T-cell activation, proliferation, and differentiation in vitro and in vivo. METHODS: We first evaluated autophagy level of TILs and influence of spermidine treatment on autophagy levels of TILs. Furthermore, we assessed the proliferative potential, phenotypical characteristics, T cell receptor (TCR) repertoire and antitumor activity of TILs with and without spermidine treatment. RESULTS: We found that autophagic flux of TILs, especially exhausted TILs that express inhibitory immunoreceptors and have impaired proliferative capacity and decreased production of cytotoxic effector molecules, was significantly impaired. The restoration of autophagic flux via spermidine treatment resulted in increased diversity of the TCR repertoire, reduced expression of inhibitory immunoreceptors (PD1, TIM3, or LAG3), enhanced proliferation and effector functions, which subsequently demonstrated the superior in vitro and in vivo antitumor activity of TILs. Our findings unveil that spermidine, as an autophagy inducer, reverses dysfunction and exhaustion of TILs and subsequently improves the antitumor activity of TILs. CONCLUSIONS: These data suggest that spermidine treatment presents an opportunity to improve adoptive TIL therapy for the treatment of solid tumors.


Asunto(s)
Linfocitos Infiltrantes de Tumor , Neoplasias , Humanos , Linfocitos Infiltrantes de Tumor/metabolismo , Espermidina/metabolismo , Espermidina/farmacología , Inmunoterapia Adoptiva/métodos , Neoplasias/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Autofagia
16.
Comput Biol Med ; 149: 105946, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36030721

RESUMEN

The physician burnout, poor ergonomics are hardly conducive to the sustainability and high quality of colonoscopy. In order to reduce doctors' workload and improve patients' experiences during colonoscopy, this paper proposes a multistage adaptive control approach based on image contour data to guide the autonomous navigation of endoscopes. First, a fast image preprocessing and contour extraction algorithms are designed. Second, different processing algorithms are developed according to the different contour information that can be clearly extracted to compute the endoscope control parameters. Third, when a clear contour cannot be extracted, a triple control method inspired by the turning of a novice car driver is devised to help the endoscope capture clear contours. The proposed multistage adaptive control approach is tested in an intestinal model over a variety of curved configurations and verified on the actual colonoscopy image. The results reveal the success of the strategy in both straight sections of this intestinal model and in tightly curved sections as small as 6 cm in radius of curvature. In the experiment, processing time for a single image is 20-25 ms and the accuracy of judging steering based on intestinal model pictures is 96.7%. Additionally, the average velocity reaches 3.04 cm/s in straight sections and 2.49 cm/s in curved sections respectively.


Asunto(s)
Algoritmos , Endoscopios , Colonoscopía , Humanos , Procesamiento de Imagen Asistido por Computador/métodos
17.
IEEE Trans Ultrason Ferroelectr Freq Control ; 69(11): 3095-3101, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35073262

RESUMEN

Ultrasound medical imaging is an entrenched and powerful tool for medical diagnosis. Image quality in ultrasound is mainly dependent on performance of piezoelectric transducer elements, which is further related to the electromechanical performance of the constituent piezoelectric materials. With rising need for piezoelectric materials with better performance and low cost, a highly 〈001〉 textured piezo ceramic, Pb(Mg1/3Nb2/3)O3-Pb(Zr, Ti)O3, has been developed. Recently, textured ceramic materials can be produced at low cost and exhibit high piezoelectric strain constants and large electromechanical coupling coefficients. In this work, 15-MHz ultrasonic transducers with an effective aperture of 2.5 mm in diameter based on these highly 〈001〉 textured ceramics have been successfully fabricated. The fabricated transducers achieved a central frequency of 15 MHz, a fractional bandwidth of 67% (at -6 dB), a high effective electromechanical coupling coefficient [Formula: see text] of 0.55, and a low insertion loss (IL) of 21 dB. Ex vivo ultrasonic imaging of a porcine eyeball was used to assess the tomography quality of the transducer. The results show that utilized textured ceramic has a great potential in developing ultrasonic devices for biomedical imaging purposes.


Asunto(s)
Plomo , Ultrasonido , Porcinos , Animales , Niobio , Titanio , Diseño de Equipo , Transductores , Cerámica
18.
Artículo en Inglés | MEDLINE | ID: mdl-36315528

RESUMEN

High element density and strict constraints of the element's size have significantly limited the design and fabrication of 2-D ultrasonic arrays, especially fully sampled 2-D arrays. Recently, 3-D printing technology has been one of the most rapidly developing fields. Along with the great progress of 3-D printing technology, complex and detailed 3-D structures have become readily available with a short iteration cycle, which allows us to reduce the complexity of routing and helps to ameliorate assembly problems in 2-D ultrasound array fabrication. In this work, we designed and fabricated 2-D ultrasound arrays for an array of applications with a pitch-shifting interposer, which allowed us to fit different array designs with the same circuit design and significantly reduce the requirements in routing and connection for 2-D array fabrication at frequencies from 4 to 10 MHz. Results demonstrated that this design would make 2-D arrays more available and affordable.


Asunto(s)
Transductores , Ultrasonido , Diseño de Equipo , Ultrasonografía/métodos
19.
Nat Commun ; 13(1): 3853, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35788594

RESUMEN

Electronic visual prostheses, or biomimetic eyes, have shown the feasibility of restoring functional vision in the blind through electrical pulses to initiate neural responses artificially. However, existing visual prostheses predominantly use wired connections or electromagnetic waves for powering and data telemetry, which raises safety concerns or couples inefficiently to miniaturized implant units. Here, we present a flexible ultrasound-induced retinal stimulating piezo-array that can offer an alternative wireless artificial retinal prosthesis approach for evoking visual percepts in blind individuals. The device integrates a two-dimensional piezo-array with 32-pixel stimulating electrodes in a flexible printed circuit board. Each piezo-element can be ultrasonically and individually activated, thus, spatially reconfigurable electronic patterns can be dynamically applied via programmable ultrasound beamlines. As a proof of concept, we demonstrate the ultrasound-induced pattern reconstruction in ex vivo murine retinal tissue, showing the potential of this approach to restore functional, life-enhancing vision in people living with blindness.


Asunto(s)
Prótesis Visuales , Animales , Biomimética , Ceguera/terapia , Humanos , Ratones , Retina/diagnóstico por imagen , Retina/fisiología , Retina/cirugía , Visión Ocular
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