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1.
IEEE Trans Neural Netw Learn Syst ; 35(3): 3052-3061, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37943652

RESUMEN

This article presents a distributed optimization framework in order to solve the plant-wide energy-saving problem of an ethylene plant. First, the ethylene production process is abstracted into a distributed network, and then, a new distributed consensus algorithm is proposed, which is called adaptive step-size-based distributed proximal consensus algorithm (ASS-DPCA). This algorithm can dynamically adjust the step size and automatically abandon the irrational evolutionary route while eliminating the dependence of optimization algorithms on model gradient information. Moreover, the designed algorithm is able to converge to an optimal solution for any convex cost functions and approach to a convex constraint set of agents over an undirected connected graph. Finally, the results of numerical simulation and industrial experiments show that the algorithm can reduce the total energy consumption of an ethylene plant with less computing time and assured consensus.

2.
Elife ; 122023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38127070

RESUMEN

Proper activation of cytotoxic T cells via the T cell receptor and the costimulatory receptor CD28 is essential for adaptive immunity against viruses, intracellular bacteria, and cancers. Through biochemical analysis of RNA:protein interactions, we uncovered a non-coding RNA circuit regulating activation and differentiation of cytotoxic T cells composed of the long non-coding RNA Malat1 (Metastasis Associated Lung Adenocarcinoma Transcript 1) and the microRNA family miR-15/16. miR-15/16 is a widely and highly expressed tumor suppressor miRNA family important for cell proliferation and survival. miR-15/16 play important roles in T cell responses to viral infection, including the regulation of antigen-specific T cell expansion and memory. Comparative Argonaute-2 high-throughput sequencing of crosslinking immunoprecipitation (AHC) combined with gene expression profiling in normal and miR-15/16-deficient mouse T cells revealed a large network of hundreds of direct miR-15/16 target mRNAs, many with functional relevance for T cell activation, survival and memory formation. Among these targets, Malat1 contained the largest absolute magnitude miR-15/16-dependent AHC peak. This binding site was among the strongest lncRNA:miRNA interactions detected in the T cell transcriptome. We used CRISPR targeting with homology directed repair to generate mice with a 5-nucleotide mutation in the miR-15/16-binding site in Malat1. This mutation interrupted Malat1:miR-15/16 interaction, and enhanced the repression of other miR-15/16 target genes, including CD28. Interrupting Malat1 interaction with miR-15/16 decreased cytotoxic T cell activation, including the expression of interleukin 2 (IL-2) and a broader CD28-responsive gene program. Accordingly, Malat1 mutation diminished memory cell persistence in mice following LCMV Armstrong and Listeria monocytogenes infection. This study marks a significant advance in the study of long non-coding RNAs in the immune system by ascribing cell-intrinsic, sequence-specific in vivo function to Malat1. These findings have implications for T cell-mediated autoimmune diseases, antiviral and anti-tumor immunity, as well as lung adenocarcinoma and other malignancies where Malat1 is overexpressed.


Asunto(s)
Células T de Memoria , MicroARNs , ARN Largo no Codificante , Linfocitos T Citotóxicos , Animales , Ratones , Antígenos CD28 , MicroARNs/genética , ARN Largo no Codificante/genética
3.
Cell ; 186(19): 4216-4234.e33, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37714135

RESUMEN

Chronic stimulation can cause T cell dysfunction and limit the efficacy of cellular immunotherapies. Improved methods are required to compare large numbers of synthetic knockin (KI) sequences to reprogram cell functions. Here, we developed modular pooled KI screening (ModPoKI), an adaptable platform for modular construction of DNA KI libraries using barcoded multicistronic adaptors. We built two ModPoKI libraries of 100 transcription factors (TFs) and 129 natural and synthetic surface receptors (SRs). Over 30 ModPoKI screens across human TCR- and CAR-T cells in diverse conditions identified a transcription factor AP4 (TFAP4) construct that enhanced fitness of chronically stimulated CAR-T cells and anti-cancer function in vitro and in vivo. ModPoKI's modularity allowed us to generate an ∼10,000-member library of TF combinations. Non-viral KI of a combined BATF-TFAP4 polycistronic construct enhanced fitness. Overexpressed BATF and TFAP4 co-occupy and regulate key gene targets to reprogram T cell function. ModPoKI facilitates the discovery of complex gene constructs to program cellular functions.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Ejercicio Físico , Humanos , Biblioteca de Genes , Inmunoterapia , Investigación
4.
bioRxiv ; 2023 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-37547023

RESUMEN

Proper activation of cytotoxic T cells via the T cell receptor and the costimulatory receptor CD28 is essential for adaptive immunity against viruses, many intracellular bacteria and cancers. Through biochemical analysis of RNA:protein interactions, we uncovered a non-coding RNA circuit regulating activation and differentiation of cytotoxic T cells composed of the long non-coding RNA Malat1 (Metastasis Associated Lung Adenocarcinoma Transcript 1) and the microRNA family miR-15/16. miR-15/16 is a widely and highly expressed tumor suppressor miRNA family important for cell proliferation and survival. miR-15/16 also play important roles in T cell responses to viral infection, including the regulation of antigen-specific T cell expansion and T cell memory. Comparative Argonaute-2 high throughput sequencing of crosslinking immunoprecipitation (Ago2 HITS-CLIP, or AHC) combined with gene expression profiling in normal and miR-15/16-deficient T cells revealed a large network of several hundred direct miR-15/16 target mRNAs, many with functional relevance for T cell activation, survival and memory formation. Among these targets, the long non-coding RNA Malat1 contained the largest absolute magnitude miR-15/16-dependent AHC peak in T cells. This binding site was also among the strongest lncRNA:miRNA interactions detected in the T cell transcriptome. We used CRISPR targeting with homology directed repair to generate mice with a 5-nucleotide mutation in the miR-15/16 binding site in Malat1. This mutation interrupted Malat1:miR-15/16 interaction, and enhanced the repression of other miR-15/16 target genes, including CD28. Interrupting Malat1 interaction with miR-15/16 decreased cytotoxic T cell activation, including the expression of IL-2 and a broader CD28-responsive gene program. Accordingly, Malat1 mutation diminished memory cell persistence following LCMV Armstrong and Listeria monocytogenes infection. This study marks a significant advance in the study of long noncoding RNAs in the immune system by ascribing cell-intrinsic, sequence-specific in vivo function to Malat1. These findings have implications for T cell-mediated autoimmune diseases, antiviral and anti-tumor immunity, as well as lung adenocarcinoma and other malignancies where Malat1 is overexpressed.

5.
bioRxiv ; 2023 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-37503101

RESUMEN

Genetic variants associated with human autoimmune diseases commonly map to non-coding control regions, particularly enhancers that function selectively in immune cells and fine-tune gene expression within a relatively narrow range of values. How such modest, cell-type-selective changes can meaningfully shape organismal disease risk remains unclear. To explore this issue, we experimentally manipulated species-conserved enhancers within the disease-associated IL2RA locus and studied accompanying changes in the progression of autoimmunity. Perturbing distinct enhancers with restricted activity in conventional T cells (Tconvs) or regulatory T cells (Tregs)-two functionally antagonistic T cell subsets-caused only modest, cell-type-selective decreases in IL2ra expression parameters. However, these same perturbations had striking and opposing effects in vivo , completely preventing or severely accelerating disease in a murine model of type 1 diabetes. Quantitative tissue imaging and computational modelling revealed that each enhancer manipulation impinged on distinct IL-2-dependent feedback circuits. These imbalances altered the intracellular signaling and intercellular communication dynamics of activated Tregs and Tconvs, producing opposing spatial domains that amplified or constrained ongoing autoimmune responses. These findings demonstrate how subtle changes in gene regulation stemming from non-coding variation can propagate across biological scales due to non-linearities in intra- and intercellular feedback circuitry, dramatically shaping disease risk at the organismal level.

6.
Nat Biomed Eng ; 7(5): 647-660, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147433

RESUMEN

CRISPR-mediated genome editing of primary human lymphocytes is typically carried out via electroporation, which can be cytotoxic, cumbersome and costly. Here we show that the yields of edited primary human lymphocytes can be increased substantially by delivering a CRISPR ribonucleoprotein mixed with an amphiphilic peptide identified through screening. We evaluated the performance of this simple delivery method by knocking out genes in T cells, B cells and natural killer cells via the delivery of Cas9 or Cas12a ribonucleoproteins or an adenine base editor. We also show that peptide-mediated ribonucleoprotein delivery paired with an adeno-associated-virus-mediated homology-directed repair template can introduce a chimaeric antigen receptor gene at the T-cell receptor α constant locus, and that the engineered cells display antitumour potency in mice. The method is minimally perturbative, does not require dedicated hardware, and is compatible with multiplexed editing via sequential delivery, which minimizes the risk of genotoxicity. The peptide-mediated intracellular delivery of ribonucleoproteins may facilitate the manufacturing of engineered T cells.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Humanos , Ratones , Animales , Edición Génica/métodos , Linfocitos T/metabolismo , Péptidos/genética , Ribonucleoproteínas
7.
Nat Immunol ; 24(4): 676-689, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36914891

RESUMEN

Mature T cells must discriminate between brief interactions with self-peptides and prolonged binding to agonists. The kinetic proofreading model posits that certain T-cell antigen receptor signaling nodes serve as molecular timers to facilitate such discrimination. However, the physiological significance of this regulatory mechanism and the pathological consequences of disrupting it are unknown. Here we report that accelerating the normally slow phosphorylation of the linker for activation of T cells (LAT) residue Y136 by introducing an adjacent Gly135Asp alteration (LATG135D) disrupts ligand discrimination in vivo. The enhanced self-reactivity of LATG135D T cells triggers excessive thymic negative selection and promotes T-cell anergy. During Listeria infection, LATG135D T cells expand more than wild-type counterparts in response to very weak stimuli but display an imbalance between effector and memory responses. Moreover, despite their enhanced engagement of central and peripheral tolerance mechanisms, mice bearing LATG135D show features associated with autoimmunity and immunopathology. Our data reveal the importance of kinetic proofreading in balancing tolerance and immunity.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Linfocitos T , Ratones , Animales , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Sustitución de Aminoácidos , Receptores de Antígenos de Linfocitos T/metabolismo , Activación de Linfocitos , Fosforilación , Fosfoproteínas/genética
8.
Nature ; 609(7925): 174-182, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36002574

RESUMEN

The efficacy of adoptive T cell therapies for cancer treatment can be limited by suppressive signals from both extrinsic factors and intrinsic inhibitory checkpoints1,2. Targeted gene editing has the potential to overcome these limitations and enhance T cell therapeutic function3-10. Here we performed multiple genome-wide CRISPR knock-out screens under different immunosuppressive conditions to identify genes that can be targeted to prevent T cell dysfunction. These screens converged on RASA2, a RAS GTPase-activating protein (RasGAP) that we identify as a signalling checkpoint in human T cells, which is downregulated upon acute T cell receptor stimulation and can increase gradually with chronic antigen exposure. RASA2 ablation enhanced MAPK signalling and chimeric antigen receptor (CAR) T cell cytolytic activity in response to target antigen. Repeated tumour antigen stimulations in vitro revealed that RASA2-deficient T cells show increased activation, cytokine production and metabolic activity compared with control cells, and show a marked advantage in persistent cancer cell killing. RASA2-knockout CAR T cells had a competitive fitness advantage over control cells in the bone marrow in a mouse model of leukaemia. Ablation of RASA2 in multiple preclinical models of T cell receptor and CAR T cell therapies prolonged survival in mice xenografted with either liquid or solid tumours. Together, our findings highlight RASA2 as a promising target to enhance both persistence and effector function in T cell therapies for cancer treatment.


Asunto(s)
Antígenos de Neoplasias , Neoplasias , Linfocitos T , Proteínas Activadoras de ras GTPasa , Animales , Antígenos de Neoplasias/inmunología , Médula Ósea , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Técnicas de Silenciamiento del Gen , Humanos , Inmunoterapia Adoptiva , Leucemia/inmunología , Leucemia/patología , Leucemia/terapia , Ratones , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Factores de Tiempo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Activadoras de ras GTPasa/deficiencia , Proteínas Activadoras de ras GTPasa/genética
9.
Nature ; 604(7905): 337-342, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35355021

RESUMEN

Decades of work have elucidated cytokine signalling and transcriptional pathways that control T cell differentiation and have led the way to targeted biologic therapies that are effective in a range of autoimmune, allergic and inflammatory diseases. Recent evidence indicates that obesity and metabolic disease can also influence the immune system1-7, although the mechanisms and effects on immunotherapy outcomes remain largely unknown. Here, using two models of atopic dermatitis, we show that lean and obese mice mount markedly different immune responses. Obesity converted the classical type 2 T helper (TH2)-predominant disease associated with atopic dermatitis to a more severe disease with prominent TH17 inflammation. We also observed divergent responses to biologic therapies targeting TH2 cytokines, which robustly protected lean mice but exacerbated disease in obese mice. Single-cell RNA sequencing coupled with genome-wide binding analyses revealed decreased activity of nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ) in TH2 cells from obese mice relative to lean mice. Conditional ablation of PPARγ in T cells revealed that PPARγ is required to focus the in vivo TH response towards a TH2-predominant state and prevent aberrant non-TH2 inflammation. Treatment of obese mice with a small-molecule PPARγ agonist limited development of TH17 pathology and unlocked therapeutic responsiveness to targeted anti-TH2 biologic therapies. These studies reveal the effects of obesity on immunological disease and suggest a precision medicine approach to target the immune dysregulation caused by obesity.


Asunto(s)
Dermatitis Atópica , PPAR gamma , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inflamación/metabolismo , Ratones , Obesidad/metabolismo , PPAR gamma/agonistas , PPAR gamma/metabolismo , Medicina de Precisión , Análisis de Secuencia de ARN , Células Th2/metabolismo
10.
Science ; 375(6581): eabi5965, 2022 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-35143305

RESUMEN

Dendritic cells (DCs) are crucial for initiating adaptive immune responses. However, the factors that control DC positioning and homeostasis are incompletely understood. We found that type-2 conventional DCs (cDC2s) in the spleen depend on Gα13 and adhesion G protein-coupled receptor family member-E5 (Adgre5, or CD97) for positioning in blood-exposed locations. CD97 function required its autoproteolytic cleavage. CD55 is a CD97 ligand, and cDC2 interaction with CD55-expressing red blood cells (RBCs) under shear stress conditions caused extraction of the regulatory CD97 N-terminal fragment. Deficiency in CD55-CD97 signaling led to loss of splenic cDC2s into the circulation and defective lymphocyte responses to blood-borne antigens. Thus, CD97 mechanosensing of RBCs establishes a migration and gene expression program that optimizes the antigen capture and presentation functions of splenic cDC2s.


Asunto(s)
Células Dendríticas/fisiología , Eritrocitos/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Bazo/citología , Bazo/inmunología , Actinas/metabolismo , Animales , Presentación de Antígeno , Antígenos/inmunología , Circulación Sanguínea , Antígenos CD55/sangre , Antígenos CD55/metabolismo , Movimiento Celular , Células Dendríticas/inmunología , Eritrocitos/metabolismo , Subunidades alfa de la Proteína de Unión al GTP G12-G13/metabolismo , Homeostasis , Factores Reguladores del Interferón/metabolismo , Ligandos , Ratones , Receptores Acoplados a Proteínas G/genética , Transducción de Señal , Bazo/irrigación sanguínea , Bazo/metabolismo , Transcripción Genética , Transcriptoma
11.
J Clin Invest ; 132(5)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35077396

RESUMEN

Anti-TNF antibodies are effective for treating patients with inflammatory bowel disease (IBD), but many patients fail to respond to anti-TNF therapy, highlighting the importance of TNF-independent disease. We previously demonstrated that acute deletion of 2 IBD susceptibility genes, A20 (Tnfaip3) and Abin-1 (Tnip1), in intestinal epithelial cells (IECs) sensitized mice to both TNF-dependent and TNF-independent death. Here we show that TNF-independent IEC death after A20 and Abin-1 deletion was rescued by germ-free derivation or deletion of MyD88, while deletion of Trif provided only partial protection. Combined deletion of Ripk3 and Casp8, which inhibits both apoptotic and necroptotic death, completely protected against death after acute deletion of A20 and Abin-1 in IECs. A20- and Abin-1-deficient IECs were sensitized to TNF-independent, TNFR1-mediated death in response to lymphotoxin α (LTα) homotrimers. Blockade of LTα in vivo reduced weight loss and improved survival when combined with partial deletion of MyD88. Biopsies of inflamed colon mucosa from patients with IBD exhibited increased LTA and IL1B expression, including a subset of patients with active colitis on anti-TNF therapy. These data show that microbial signals, MyD88, and LTα all contribute to TNF-independent intestinal injury.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Linfotoxina-alfa , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Apoptosis , Células Epiteliales/metabolismo , Epitelio/metabolismo , Humanos , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/metabolismo , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Linfotoxina-alfa/farmacología , Ratones , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Inhibidores del Factor de Necrosis Tumoral
12.
Sci Immunol ; 6(60)2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34088745

RESUMEN

P2RY8 promotes the confinement and growth regulation of germinal center (GC) B cells, and loss of human P2RY8 is associated with B cell lymphomagenesis. The metabolite S-geranylgeranyl-l-glutathione (GGG) is a P2RY8 ligand. The mechanisms controlling GGG distribution are poorly understood. Here, we show that gamma-glutamyltransferase-5 (Ggt5) expression in stromal cells was required for GGG catabolism and confinement of P2RY8-expressing cells to GCs. We identified the ATP-binding cassette subfamily C member 1 (Abcc1) as a GGG transporter and showed that Abcc1 expression by hematopoietic cells was necessary for P2RY8-mediated GC confinement. Furthermore, we discovered that P2RY8 and GGG negatively regulated trafficking of B and T cells to the bone marrow (BM). P2RY8 loss-of-function human T cells increased their BM homing. By defining how GGG distribution was determined and identifying sites of P2RY8 activity, this work helps establish how disruptions in P2RY8 function contribute to lymphomagenesis and other disease states.


Asunto(s)
Glutatión , Linfocitos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Receptores Purinérgicos P2Y , gamma-Glutamiltransferasa , Animales , Femenino , Humanos , Masculino , Ratones , gamma-Glutamiltransferasa/genética , gamma-Glutamiltransferasa/metabolismo , Técnicas de Silenciamiento del Gen , Técnicas de Inactivación de Genes , Glutatión/metabolismo , Células HEK293 , Activación de Linfocitos , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones Noqueados , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Receptores Purinérgicos P2Y/genética , Receptores Purinérgicos P2Y/metabolismo
13.
Nat Immunol ; 21(10): 1267-1279, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32868928

RESUMEN

Antigen stimulation (signal 1) triggers B cell proliferation and primes B cells to recruit, engage and respond to T cell help (signal 2). Failure to receive signal 2 within a defined time window results in B cell apoptosis, yet the mechanisms that enforce dependence on co-stimulation are incompletely understood. Nr4a1-3 encode a small family of orphan nuclear receptors that are rapidly induced by B cell antigen receptor stimulation. Here, we show that Nr4a1 and Nr4a3 play partially redundant roles to restrain B cell responses to antigen in the absence of co-stimulation and do so, in part, by repressing the expression of BATF and, consequently, MYC. The NR4A family also restrains B cell access to T cell help by repressing expression of the T cell chemokines CCL3 and CCL4, as well as CD86 and ICAM1. Such NR4A-mediated regulation plays a role specifically under conditions of competition for limiting T cell help.


Asunto(s)
Linfocitos B/inmunología , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Comunicación Celular , Proliferación Celular , Células Cultivadas , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Inmunidad Humoral , Inmunomodulación , Activación de Linfocitos , Ratones , Ratones Noqueados , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Receptores de Hormona Tiroidea/genética , Receptores de Hormona Tiroidea/metabolismo , Transducción de Señal
14.
Nature ; 582(7812): 416-420, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32499641

RESUMEN

Regulatory T (Treg) cells are required to control immune responses and maintain homeostasis, but are a significant barrier to antitumour immunity1. Conversely, Treg instability, characterized by loss of the master transcription factor Foxp3 and acquisition of proinflammatory properties2, can promote autoimmunity and/or facilitate more effective tumour immunity3,4. A comprehensive understanding of the pathways that regulate Foxp3 could lead to more effective Treg therapies for autoimmune disease and cancer. The availability of new functional genetic tools has enabled the possibility of systematic dissection of the gene regulatory programs that modulate Foxp3 expression. Here we developed a CRISPR-based pooled screening platform for phenotypes in primary mouse Treg cells and applied this technology to perform a targeted loss-of-function screen of around 500 nuclear factors to identify gene regulatory programs that promote or disrupt Foxp3 expression. We identified several modulators of Foxp3 expression, including ubiquitin-specific peptidase 22 (Usp22) and ring finger protein 20 (Rnf20). Usp22, a member of the deubiquitination module of the SAGA chromatin-modifying complex, was revealed to be a positive regulator that stabilized Foxp3 expression; whereas the screen suggested that Rnf20, an E3 ubiquitin ligase, can serve as a negative regulator of Foxp3. Treg-specific ablation of Usp22 in mice reduced Foxp3 protein levels and caused defects in their suppressive function that led to spontaneous autoimmunity but protected against tumour growth in multiple cancer models. Foxp3 destabilization in Usp22-deficient Treg cells could be rescued by ablation of Rnf20, revealing a reciprocal ubiquitin switch in Treg cells. These results reveal previously unknown modulators of Foxp3 and demonstrate a screening method that can be broadly applied to discover new targets for Treg immunotherapies for cancer and autoimmune disease.


Asunto(s)
Sistemas CRISPR-Cas , Factores de Transcripción Forkhead/metabolismo , Linfocitos T Reguladores/metabolismo , Animales , Autoinmunidad/inmunología , Células Cultivadas , Factores de Transcripción Forkhead/biosíntesis , Edición Génica , Regulación de la Expresión Génica , Humanos , Inmunoterapia , Masculino , Ratones , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/prevención & control , Estabilidad Proteica , Reproducibilidad de los Resultados , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Ubiquitina Tiolesterasa/deficiencia , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/metabolismo
15.
Immunity ; 51(2): 310-323.e7, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31204070

RESUMEN

The tumor necrosis factor receptor superfamily member HVEM is one of the most frequently mutated surface proteins in germinal center (GC)-derived B cell lymphomas. We found that HVEM deficiency increased B cell competitiveness during pre-GC and GC responses. The immunoglobulin (Ig) superfamily protein BTLA regulated HVEM-expressing B cell responses independently of B-cell-intrinsic signaling via HVEM or BTLA. BTLA signaling into T cells through the phosphatase SHP1 reduced T cell receptor (TCR) signaling and preformed CD40 ligand mobilization to the immunological synapse, thus diminishing the help delivered to B cells. Moreover, T cell deficiency in BTLA cooperated with B cell Bcl-2 overexpression, leading to GC B cell outgrowth. These results establish that HVEM restrains the T helper signals delivered to B cells to influence GC selection outcomes, and they suggest that BTLA functions as a cell-extrinsic suppressor of GC B cell lymphomagenesis.


Asunto(s)
Linfocitos B/inmunología , Centro Germinal/inmunología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptores Inmunológicos/metabolismo , Miembro 14 de Receptores del Factor de Necrosis Tumoral/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Proliferación Celular , Sinapsis Inmunológicas , Activación de Linfocitos , Ratones , Ratones Noqueados , Ratones Transgénicos , Comunicación Paracrina , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores Inmunológicos/genética , Transducción de Señal
16.
Polymers (Basel) ; 11(6)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167391

RESUMEN

In this paper, an atomic force microscope (AFM) was used to study the nano-morphology characteristics of styrene-butadiene-styrene block copolymer (SBS) modified bitumen. The effects of SBS content and short-term aging on the nano-morphology parameters of bitumen were studied. The correlation between nano-morphology parameters and main pavement performances of SBS modified bitumen was analyzed. The results show that with the increase of SBS content, the average area of bee-like structure and the proportions of bee-like structure area of SBS modified bitumen increases gradually, the roughness of the whole image and the roughness of the lightweight component region decreases gradually, but the increasing or decreasing trend is no longer obvious when the content of SBS is more than 4%. The maximum height difference of SBS modified bitumen is linear with the content of SBS. The larger the content of SBS, the smaller the influence of short-term aging on the nano-morphology of SBS modified bitumen. The penetration degree will decrease and the softening point will increase with the increase of the proportion of bee-like structure area of SBS modified bitumen. The ductility will decrease with the increase of the roughness of the lightweight component region. The ductility and the Brookfield viscosity will increase with the increase of the maximum height difference. The research results provided a reference for defining quantifiable nano-parameters of SBS modified bitumen and establishing the relationship between nano-parameters and pavement performances.

17.
Commun Biol ; 2: 70, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30793048

RESUMEN

A persistent concern with CRISPR-Cas9 gene editing has been the potential to generate mutations at off-target genomic sites. While CRISPR-engineering mice to delete a ~360 bp intronic enhancer, here we discovered a founder line that had marked immune dysregulation caused by a 24 kb tandem duplication of the sequence adjacent to the on-target deletion. Our results suggest unintended repair of on-target genomic cuts can cause pathogenic "bystander" mutations that escape detection by routine targeted genotyping assays.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica/métodos , Subunidad alfa del Receptor de Interleucina-2/genética , Mutación , Linfocitos T Reguladores/inmunología , Linfocitos T/inmunología , Animales , Secuencia de Bases , Células Cultivadas , Daño del ADN , Reparación del ADN , Duplicación de Gen , Regulación de la Expresión Génica/inmunología , Subunidad alfa del Receptor de Interleucina-2/inmunología , Ratones Endogámicos NOD , Linfocitos T/metabolismo , Linfocitos T Reguladores/metabolismo
18.
Biosci Rep ; 38(5)2018 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-30181378

RESUMEN

Renalase gene rs2576178 polymorphism has been demonstrated to be a risk factor of ischemic stroke, essential hypertension, and end-stage renal disease, but the association Renalase with risk of coronary artery disease (CAD) has been less reported. Therefore, we detected Renalase rs2576178 polymorphism in 449 CAD patients and 507 healthy controls using matrix-assisted laser-desorption ionization (MALDI)/time of flight (TOF)-mass spectrometry (MS). It was found that GG genotype or G allele of rs2576178 polymorphism was associated with the risk of CAD. Stratified analysis indicated that Renalase polymorphism significantly increased the risk of CAD in females, smokers, and alcoholics. However, there was no significant association between different genotypes of rs2576178 polymorphism and clinical parameters. In summary, Renalase rs2576178 polymorphism is associated with increased risk of CAD, but this finding should be confirmed by larger studies with more diverse ethnic populations.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Predisposición Genética a la Enfermedad , Monoaminooxidasa/genética , Accidente Cerebrovascular/genética , Alelos , Pueblo Asiatico/genética , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Fallo Renal Crónico/genética , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/fisiopatología
19.
Nature ; 559(7715): E13, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29899441

RESUMEN

In this Letter, analysis of steady-state regulatory T (Treg) cell percentages from Il2ra enhancer deletion (EDEL) and wild-type (WT) mice revealed no differences between them (Extended Data Fig. 9d). This analysis included two mice whose genotypes were incorrectly assigned. Even after correction of the genotypes, no significant differences in Treg cell percentages were seen when data across experimental cohorts were averaged (as was done in Extended Data Fig. 9d). However, if we normalize the corrected data to account for variation among experimental cohorts, a subtle decrease in EDEL Treg cell percentages is revealed and, using the corrected and normalized data, we have redrawn Extended Data Fig. 9d in Supplementary Fig. 1. The Supplementary Information to this Amendment contains the corrected and reanalysed Extended Data Fig. 9d. The sentence "This enhancer deletion (EDEL) strain also had no obvious T cell phenotypes at steady state (Extended Data Fig. 9)." should read: "This enhancer deletion (EDEL) strain had a small decrease in the percentage of Treg cells (Extended Data Fig. 9).". This error does not affect any of the main figures in the Letter or the data from mice with the human autoimmune-associated single nucleotide polymorphism (SNP) knocked in or with a 12-base-pair deletion at the site (12DEL). In addition, we stated in the Methods that we observed consistent immunophenotypes of EDEL mice across three founders, but in fact, we observed consistent phenotypes in mice from two founders. This does not change any of our conclusions and the original Letter has not been corrected.

20.
Nature ; 549(7670): 111-115, 2017 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-28854172

RESUMEN

The majority of genetic variants associated with common human diseases map to enhancers, non-coding elements that shape cell-type-specific transcriptional programs and responses to extracellular cues. Systematic mapping of functional enhancers and their biological contexts is required to understand the mechanisms by which variation in non-coding genetic sequences contributes to disease. Functional enhancers can be mapped by genomic sequence disruption, but this approach is limited to the subset of enhancers that are necessary in the particular cellular context being studied. We hypothesized that recruitment of a strong transcriptional activator to an enhancer would be sufficient to drive target gene expression, even if that enhancer was not currently active in the assayed cells. Here we describe a discovery platform that can identify stimulus-responsive enhancers for a target gene independent of stimulus exposure. We used tiled CRISPR activation (CRISPRa) to synthetically recruit a transcriptional activator to sites across large genomic regions (more than 100 kilobases) surrounding two key autoimmunity risk loci, CD69 and IL2RA. We identified several CRISPRa-responsive elements with chromatin features of stimulus-responsive enhancers, including an IL2RA enhancer that harbours an autoimmunity risk variant. Using engineered mouse models, we found that sequence perturbation of the disease-associated Il2ra enhancer did not entirely block Il2ra expression, but rather delayed the timing of gene activation in response to specific extracellular signals. Enhancer deletion skewed polarization of naive T cells towards a pro-inflammatory T helper (TH17) cell state and away from a regulatory T cell state. This integrated approach identifies functional enhancers and reveals how non-coding variation associated with human immune dysfunction alters context-specific gene programs.


Asunto(s)
Autoinmunidad/genética , Sistemas CRISPR-Cas/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Elementos de Facilitación Genéticos/genética , Animales , Antígenos CD/biosíntesis , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/biosíntesis , Antígenos de Diferenciación de Linfocitos T/genética , Antígenos de Diferenciación de Linfocitos T/inmunología , Diferenciación Celular , Línea Celular , Cromatina/genética , Femenino , Regulación de la Expresión Génica/genética , Humanos , Subunidad alfa del Receptor de Interleucina-2/biosíntesis , Subunidad alfa del Receptor de Interleucina-2/genética , Subunidad alfa del Receptor de Interleucina-2/inmunología , Lectinas Tipo C/biosíntesis , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Ratones , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Células Th17/citología , Células Th17/inmunología
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