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1.
Cell ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38971151

RESUMEN

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Nat Immunol ; 25(1): 142-154, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38049580

RESUMEN

Spleen marginal zone (MZ) B cells are important for antibody responses against blood-borne antigens. The signals they use to detect exposure to blood are not well defined. Here, using intravital two-photon microscopy in mice, we observe transient contacts between MZ B cells and red blood cells that are in flow. We show that MZ B cells use adhesion G-protein-coupled receptor ADGRE5 (CD97) for retention in the spleen. CD97 function in MZ B cells depends on its ability to undergo autoproteolytic cleavage and signaling via Gα13 and ARHGEF1. Red blood cell expression of the CD97 ligand CD55 is required for MZ B cell homeostasis. Applying a pulling force on CD97-transfected cells using an optical C-trap and CD55+ beads leads to accumulation of active RhoA and membrane retraction. Finally, we show that CD97 deficiency leads to a reduced T cell-independent IgM response. Thus, our studies provide evidence that MZ B cells use mechanosensing to position in a manner that enhances antibody responses against blood-borne antigens.


Asunto(s)
Linfocitos B , Tejido Linfoide , Ratones , Animales , Bazo/metabolismo , Transducción de Señal , Antígenos CD55/metabolismo , Eritrocitos
3.
Immunity ; 56(4): 783-796.e7, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-36827982

RESUMEN

Diet profoundly influences physiology. Whereas over-nutrition elevates risk for disease via its influence on immunity and metabolism, caloric restriction and fasting appear to be salutogenic. Despite multiple correlations observed between diet and health, the underlying biology remains unclear. Here, we identified a fasting-induced switch in leukocyte migration that prolongs monocyte lifespan and alters susceptibility to disease in mice. We show that fasting during the active phase induced the rapid return of monocytes from the blood to the bone marrow. Monocyte re-entry was orchestrated by hypothalamic-pituitary-adrenal (HPA) axis-dependent release of corticosterone, which augmented the CXCR4 chemokine receptor. Although the marrow is a safe haven for monocytes during nutrient scarcity, re-feeding prompted mobilization culminating in monocytosis of chronologically older and transcriptionally distinct monocytes. These shifts altered response to infection. Our study shows that diet-in particular, a diet's temporal dynamic balance-modulates monocyte lifespan with consequences for adaptation to external stressors.


Asunto(s)
Médula Ósea , Monocitos , Ratones , Animales , Células de la Médula Ósea , Ayuno , Quimiocinas/metabolismo
4.
Immunity ; 54(10): 2245-2255.e4, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34464595

RESUMEN

BCL6 is required for development of follicular T helper (Tfh) cells to support germinal center (GC) formation. However, it is not clear what unique functions programmed by BCL6 can explain its absolute essentiality in T cells for GC formation. We found that ablation of one Bcl6 allele did not appreciably alter early T cell activation and follicular localization but inhibited GC formation and Tfh cell maintenance. BCL6 impinged on Tfh calcium signaling and also controlled Tfh entanglement with and CD40L delivery to B cells. Amounts of BCL6 protein and nominal frequencies of Tfh cells markedly changed within hours after strengths of T-B cell interactions were altered in vivo, while CD40L overexpression rectified both defective GC formation and Tfh cell maintenance because of the BCL6 haploinsufficiency. Our results reveal BCL6 functions in Tfh cells that are essential for GC formation and suggest that BCL6 helps maintain Tfh cell phenotypes in a T cell non-autonomous manner.


Asunto(s)
Linfocitos B/inmunología , Centro Germinal/inmunología , Activación de Linfocitos/inmunología , Proteínas Proto-Oncogénicas c-bcl-6/inmunología , Células T Auxiliares Foliculares/inmunología , Animales , Ratones
5.
Immunity ; 54(10): 2256-2272.e6, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34555336

RESUMEN

B cells within germinal centers (GCs) enter cycles of antibody affinity maturation or exit the GC as memory cells or plasma cells. Here, we examined the contribution of interleukin (IL)-4 on B cell fate decisions in the GC. Single-cell RNA-sequencing identified a subset of light zone GC B cells expressing high IL-4 receptor-a (IL4Ra) and CD23 and lacking a Myc-associated signature. These cells could differentiate into pre-memory cells. B cell-specific deletion of IL4Ra or STAT6 favored the pre-memory cell trajectory, and provision of exogenous IL-4 in a wild-type context reduced pre-memory cell frequencies. IL-4 acted during antigen-specific interactions but also influenced bystander cells. Deletion of IL4Ra from follicular dendritic cells (FDCs) increased the availability of IL-4 in the GC, impaired the selection of affinity-matured B cells, and reduced memory cell generation. We propose that GC FDCs establish a niche that limits bystander IL-4 activity, focusing IL-4 action on B cells undergoing selection and enhancing memory cell differentiation.


Asunto(s)
Linfocitos B/inmunología , Diferenciación Celular/inmunología , Células Dendríticas Foliculares/inmunología , Centro Germinal/inmunología , Memoria Inmunológica/inmunología , Interleucina-4/inmunología , Animales , Subgrupos de Linfocitos B/inmunología , Ratones
6.
Immunity ; 54(8): 1728-1744.e7, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34343498

RESUMEN

Inflammatory bowel disease (IBD) mainly includes Crohn's disease (CD) and ulcerative colitis (UC). Immune disorders play an essential role in the pathogenesis of these two IBDs, but the differences in the immune microenvironment of the colon and their underlying mechanisms remain poorly investigated. Here we examined the immunological features and metabolic microenvironment of untreated individuals with IBD by multiomics analyses. Modulation of CD-specific metabolites, particularly reduced selenium, can obviously shape type 1 T helper (Th1) cell differentiation, which is specifically enriched in CD. Selenium supplementation suppressed the symptoms and onset of CD and Th1 cell differentiation via selenoprotein W (SELW)-mediated cellular reactive oxygen species scavenging. SELW promoted purine salvage pathways and inhibited one-carbon metabolism by recruiting an E3 ubiquitin ligase, tripartite motif-containing protein 21, which controlled the stability of serine hydroxymethyltransferase 2. Our work highlights selenium as an essential regulator of T cell responses and potential therapeutic targets in CD.


Asunto(s)
Antioxidantes/farmacología , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/inmunología , Selenio/farmacología , Selenoproteína W/metabolismo , Células TH1/citología , Diferenciación Celular/inmunología , Polaridad Celular , Colon/inmunología , Colon/patología , Glicina Hidroximetiltransferasa/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Ribonucleoproteínas/metabolismo , Células TH1/inmunología , Ubiquitina-Proteína Ligasas/metabolismo
7.
Cell ; 162(3): 580-92, 2015 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-26213385

RESUMEN

Although it is known that the centrioles play instructive roles in pericentriolar material (PCM) assembly and that the PCM is essential for proper centriole formation, the mechanism that governs centriole-PCM interaction is poorly understood. Here, we show that ATF5 forms a characteristic 9-fold symmetrical ring structure in the inner layer of the PCM outfitting the proximal end of the mother centriole. ATF5 controls the centriole-PCM interaction in a cell-cycle- and centriole-age-dependent manner. Interaction of ATF5 with polyglutamylated tubulin (PGT) on the mother centriole and with PCNT in the PCM renders ATF5 as a required molecule in mother centriole-directed PCM accumulation and in PCM-dependent centriole formation. ATF5 depletion blocks PCM accumulation at the centrosome and causes fragmentation of centrioles, leading to the formation of multi-polar mitotic spindles and genomic instability. These data show that ATF5 is an essential structural protein that is required for the interaction between the mother centriole and the PCM.


Asunto(s)
Factores de Transcripción Activadores/metabolismo , Centriolos/metabolismo , Centrosoma/metabolismo , Citoesqueleto/metabolismo , Regulación hacia Abajo , Inestabilidad Genómica , Células HeLa , Humanos , Huso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
8.
Genome Res ; 34(1): 134-144, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38191205

RESUMEN

Large-scale genetic mutant libraries are powerful approaches to interrogating genotype-phenotype correlations and identifying genes responsible for certain environmental stimuli, both of which are the central goal of life science study. We produced the first large-scale CRISPR-Cas9-induced library in a nonmodel multicellular organism, Bombyx mori We developed a piggyBac-delivered binary genome editing strategy, which can simultaneously meet the requirements of mixed microinjection, efficient multipurpose genetic operation, and preservation of growth-defect lines. We constructed a single-guide RNA (sgRNA) plasmid library containing 92,917 sgRNAs targeting promoters and exons of 14,645 protein-coding genes, established 1726 transgenic sgRNA lines following microinjection of 66,650 embryos, and generated 300 mutant lines with diverse phenotypic changes. Phenomic characterization of mutant lines identified a large set of genes responsible for visual phenotypic or economically valuable trait changes. Next, we performed pooled context-specific positive screens for tolerance to environmental pollutant cadmium exposure, and identified KWMTBOMO12902 as a strong candidate gene for breeding applications in sericulture industry. Collectively, our results provide a novel and versatile approach for functional B. mori genomics, as well as a powerful resource for identifying the potential of key candidate genes for improving various economic traits. This study also shows the effectiveness, practicality, and convenience of large-scale mutant libraries in other nonmodel organisms.


Asunto(s)
Bombyx , Animales , Bombyx/genética , ARN Guía de Sistemas CRISPR-Cas , Mutagénesis , Edición Génica/métodos , Animales Modificados Genéticamente/genética , Sistemas CRISPR-Cas
9.
Nature ; 592(7852): 133-137, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33597749

RESUMEN

Antibody affinity maturation depends on positive selection in germinal centres (GCs) of rare B cell clones that acquire higher-affinity B cell receptors via somatic hypermutation, present more antigen to follicular helper T (TFH) cells and, consequently, receive more contact-dependent T cell help1. As these GC B cells and TFH cells do not maintain long-lasting contacts in the chaotic GC environment2-4, it is unclear how sufficient T cell help is cumulatively focused onto those rare clones. Here we show that, upon stimulation of CD40, GC B cells upregulate the chemokine CCL22 and to a lesser extent CCL17. By engaging the chemokine receptor CCR4 on TFH cells, CCL22 and CCL17 can attract multiple helper cells from a distance, thus increasing the chance of productive help. During a GC response, B cells that acquire higher antigen-binding affinities express higher levels of CCL22, which in turn 'highlight' these high-affinity GC B cells. Acute increase or blockade of TFH cells helps to rapidly increase or decrease CCL22 expression by GC B cells, respectively. Therefore, a chemokine-based intercellular reaction circuit links the amount of T cell help that individual B cells have received recently to their subsequent ability to attract more help. When CCL22 and CCL17 are ablated in B cells, GCs form but B cells are not affinity-matured efficiently. When competing with wild-type B cells in the same reaction, B cells lacking CCL22 and CCL17 receive less T cell help to maintain GC participation or develop into bone-marrow plasma cells. By uncovering a chemokine-mediated mechanism that highlights affinity-improved B cells for preferential help from TFH cells, our study reveals a principle of spatiotemporal orchestration of GC positive selection.


Asunto(s)
Quimiocina CCL22/metabolismo , Centro Germinal/citología , Centro Germinal/inmunología , Animales , Linfocitos B/citología , Linfocitos B/inmunología , Células Cultivadas , Quimiocina CCL17/deficiencia , Quimiocina CCL17/genética , Quimiocina CCL22/deficiencia , Quimiocina CCL22/genética , Femenino , Humanos , Masculino , Ratones , Tonsila Palatina/citología , Receptores CCR4/deficiencia , Receptores CCR4/genética , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología , Regulación hacia Arriba
10.
Blood ; 2024 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861666

RESUMEN

Pirtobrutinib is a highly selective, non-covalent (reversible) Bruton tyrosine kinase inhibitor (BTKi). Patients with relapsed or refractory (R/R) chronic lymphocytic leukemia (CLL) were treated with fixed-duration pirtobrutinib plus venetoclax (PV) or pirtobrutinib plus venetoclax and rituximab (PVR) in this phase 1b trial (NCT03740529). Prior covalent BTKi therapy was allowed, but not prior venetoclax. Patients were assigned to receive PV (n=15) or PVR (n=10) for 25 cycles. Median age was 66 years (range, 39-78). Median prior lines of therapy was 2 (range, 1-4), and 17 (68%) patients had received prior covalent BTKi. At the data-cutoff date (May 5, 2023), median time on study was 27.0 months for PV and 23.3 months for PVR. Overall response rates were 93.3% (95% CI:68.1-99.8%) for PV and 100% (95% CI:69.2-100.0%) for PVR, with 10 complete responses (PV:7; PVR:3). After 12 cycles of treatment, 85.7% (95% CI:57.2-98.2%) of PV and 90.0% (95% CI:55.5-99.7%) of PVR patients achieved undetectable minimal residual disease assessed in peripheral blood by clonoSEQ® assay at a sensitivity of <1x10-4. Progression-free survival at 18 months was 92.9% (95% CI: 59.1-99.0) for PV patients and 80.0% (95% CI: 40.9-94.6) for PVR patients. No DLTs were observed in either treatment combination during the 5-week assessment period. The most common grade ≥3 adverse events for all patients included neutropenia (52%) and anemia (16%). Adverse events led to dose reduction in 3 patients and discontinuation in 2. In conclusion, fixed-duration PV or PVR was well tolerated and had promising efficacy in patients with R/R CLL, including patients previously treated with a covalent BTKi.

11.
J Immunol ; 212(3): 375-388, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38117802

RESUMEN

The etiology and pathogenesis of pemphigus vulgaris (PV) entail intricate interactions between immune cells and epithelial cells. However, the specific subtypes of immune cells involved in PV, along with their respective roles, remain elusive. Likewise, the precise functions and mechanisms by which glucocorticoids affect cell types within the disease context require further elucidation. To address these knowledge gaps, we performed 5' single-cell RNA sequencing, combined with V(D)J enrichment on buccal mucosal lesions and peripheral blood samples from treatment-naive patients with PV, in conjunction with post-treatment peripheral blood samples obtained after oral prednisone treatment. Our findings suggest that the IL-1α signaling pathway, myeloid APCs, inflammatory CD8+ resident memory T cells, and dysfunctional CD4+ regulatory T cells are involved in the pathogenesis of PV. Part of these findings were validated by immunohistochemical assays and multiplex immunofluorescence assays. Furthermore, our results highlight the significant impact of prednisone treatment on monocytes and mucosal-associated invariant T cells while revealing a limited effect on CD4+ regulatory T cells. Additionally, we present the CDR3 amino acid sequence of BCR related to PV disease and investigate the characteristics of TCR/BCR clonotypes. In conclusion, our study provides a comprehensive understanding of PV, particularly focusing on the mucosal-dominant type, and sheds light on the effects of glucocorticoids within the PV context. These insights hold promise for the development of new therapeutic strategies in this autoimmune disorder.


Asunto(s)
Enfermedades Autoinmunes , Pénfigo , Humanos , Pénfigo/tratamiento farmacológico , Pénfigo/genética , Prednisona/uso terapéutico , Transcriptoma , Linfocitos T Reguladores , Glucocorticoides
12.
Mol Cell ; 70(3): 395-407.e4, 2018 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-29727616

RESUMEN

Telomeres and telomere-binding proteins form complex secondary nucleoprotein structures that are critical for genome integrity but can present serious challenges during telomere DNA replication. It remains unclear how telomere replication stress is resolved during S phase. Here, we show that the BUB3-BUB1 complex, a component in spindle assembly checkpoint, binds to telomeres during S phase and promotes telomere DNA replication. Loss of the BUB3-BUB1 complex results in telomere replication defects, including fragile and shortened telomeres. We also demonstrate that the telomere-binding ability of BUB3 and kinase activity of BUB1 are indispensable to BUB3-BUB1 function at telomeres. TRF2 targets BUB1-BUB3 to telomeres, and BUB1 can directly phosphorylate TRF1 and promote TRF1 recruitment of BLM helicase to overcome replication stress. Our findings have uncovered previously unknown roles for the BUB3-BUB1 complex in S phase and shed light on how proteins from diverse pathways function coordinately to ensure proper telomere replication and maintenance.


Asunto(s)
Proteínas de Ciclo Celular/genética , Replicación del ADN/genética , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas Serina-Treonina Quinasas/genética , Telómero/genética , Línea Celular , Línea Celular Tumoral , ADN Helicasas/genética , Células HEK293 , Células HeLa , Humanos , Puntos de Control de la Fase M del Ciclo Celular/genética , Fase S/genética , Huso Acromático/genética , Proteínas de Unión a Telómeros/genética
13.
Nucleic Acids Res ; 52(W1): W238-W247, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38709873

RESUMEN

Small ubiquitin-like modifiers (SUMOs) are tiny but important protein regulators involved in orchestrating a broad spectrum of biological processes, either by covalently modifying protein substrates or by noncovalently interacting with other proteins. Here, we report an updated server, GPS-SUMO 2.0, for the prediction of SUMOylation sites and SUMO-interacting motifs (SIMs). For predictor training, we adopted three machine learning algorithms, penalized logistic regression (PLR), a deep neural network (DNN), and a transformer, and used 52 404 nonredundant SUMOylation sites in 8262 proteins and 163 SIMs in 102 proteins. To further increase the accuracy of predicting SUMOylation sites, a pretraining model was first constructed using 145 545 protein lysine modification sites, followed by transfer learning to fine-tune the model. GPS-SUMO 2.0 exhibited greater accuracy in predicting SUMOylation sites than did other existing tools. For users, one or multiple protein sequences or identifiers can be input, and the prediction results are shown in a tabular list. In addition to the basic statistics, we integrated knowledge from 35 public resources to annotate SUMOylation sites or SIMs. The GPS-SUMO 2.0 server is freely available at https://sumo.biocuckoo.cn/. We believe that GPS-SUMO 2.0 can serve as a useful tool for further analysis of SUMOylation and SUMO interactions.


Asunto(s)
Internet , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina , Programas Informáticos , Sumoilación , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Aprendizaje Automático , Secuencias de Aminoácidos , Humanos , Algoritmos , Sitios de Unión
14.
Proc Natl Acad Sci U S A ; 120(16): e2300099120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37040412

RESUMEN

B cells that bind soluble autoantigens receive chronic signaling via the B cell receptor (signal-1) in the absence of strong costimulatory signals (signal-2), and this leads to their elimination in peripheral tissues. The factors determining the extent of soluble autoantigen-binding B cell elimination are not fully understood. Here we demonstrate that the elimination of B cells chronically exposed to signal-1 is promoted by cathepsin B (Ctsb). Using hen egg lysozyme-specific (HEL-specific) immunoglobulin transgenic (MD4) B cells and mice harboring circulating HEL, we found improved survival and increased proliferation of HEL-binding B cells in Ctsb-deficient mice. Bone marrow chimera experiments established that both hematopoietic and nonhematopoietic sources of Ctsb were sufficient to promote peripheral B cell deletion. The depletion of CD4+ T cells overcame the survival and growth advantage provided by Ctsb deficiency, as did blocking CD40L or removing CD40 from the chronically antigen-engaged B cells. Thus, we suggest that Ctsb acts extracellularly to reduce soluble autoantigen-binding B cell survival and that its actions restrain CD40L-dependent pro-survival effects. These findings identify a role for cell-extrinsic protease activity in establishing a peripheral self-tolerance checkpoint.


Asunto(s)
Péptido Hidrolasas , Tolerancia Periférica , Ratones , Animales , Ratones Transgénicos , Ligando de CD40 , Catepsina B , Ratones Endogámicos C57BL , Autoantígenos
15.
Proc Natl Acad Sci U S A ; 120(41): e2304988120, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37782782

RESUMEN

Previous evaluations on the biophysical potential of forest carbon sink have focused on forestation area distribution and the associated carbon stock for equilibrium-state forests after centuries-long growth. These approaches, however, have limited relevance for climate policies because they ignore the near-term and mid-term decadal carbon uptake dynamics and suitable forest species for forestation. This study developed a forestation roadmap to support China's "carbon neutrality" objective in 2060 by addressing three key questions of forestation: where, with what forest species, and when to afforest. The results yielded a high-confidence potential forestation map for China at a resolution of 1 km with the identified optimal native forest type or species. Our analysis revealed an additional 78 Mha suitable for forestation up to the 2060s, a 43% increase on the current forest area. Selecting forest species for maximal carbon stock in addition to maximizing local environmental suitability enabled almost a doubling in forest carbon sink potential. Progressive forestation of this area can fix a considerable amount of CO2 and compensate for the carbon sink decline in existing forests. Altogether, the entire forest ecosystem can support a persistent biophysical carbon sink potential of 0.4 Pg C y-1 by 2060 and 0.2 Pg C y-1 by 2100, offsetting 7 to 14% of the current national fossil CO2 emissions. Our research provides an example of building a forestation roadmap toward a sustained forest carbon sink, which creates a critical time window for the emission cuts required by the goal of carbon neutrality.


Asunto(s)
Ecosistema , Árboles , Carbono/análisis , Dióxido de Carbono/análisis , Bosques , China , Secuestro de Carbono
16.
Proc Natl Acad Sci U S A ; 120(3): e2209184120, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36626553

RESUMEN

Monocytes play a key role in innate immunity by eliminating pathogens, releasing high levels of cytokines, and differentiating into several cell types, including macrophages and dendritic cells. Similar to other phagocytes, monocytes produce superoxide anions through the NADPH oxidase complex, which is composed of two membrane proteins (p22phox and gp91phox/NOX2) and four cytosolic proteins (p47phox, p67phox, p40phox and Rac1). The pathways involved in NADPH oxidase activation in monocytes are less known than those in neutrophils. Here, we show that p22phox is associated with Rho-associated coiled-coil kinase 2 (ROCK2) in human monocytes but not neutrophils. This interaction occurs between the cytosolic region of p22phox (amino acids 132 to 195) and the coiled-coil region of ROCK2 (amino acids 400 to 967). Interestingly, ROCK2 does not phosphorylate p22phox, p40phox, p67phox, or gp91phox in vitro but phosphorylates p47phox on Ser304, Ser315, Ser320 and Ser328. Furthermore, KD025, a selective inhibitor of ROCK2, inhibited reactive oxygen species (ROS) production and p47phox phosphorylation in monocytes. Specific inhibition of ROCK2 expression in THP1-monocytic cell line by siRNA inhibited ROS production. These data show that ROCK2 interacts with p22phox and phosphorylates p47phox, and suggest that p22phox could be a shuttle for ROCK2 to allow p47phox phosphorylation and NADPH oxidase activation in human monocytes.


Asunto(s)
Monocitos , NADPH Oxidasas , Quinasas Asociadas a rho , Humanos , Aminoácidos , Monocitos/metabolismo , NADPH Oxidasas/metabolismo , Fosfoproteínas/metabolismo , Especies Reactivas de Oxígeno , Quinasas Asociadas a rho/metabolismo
17.
Immunol Rev ; 306(1): 25-42, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35147233

RESUMEN

Spleen dendritic cells (DC) are critical for initiation of adaptive immune responses against blood-borne invaders. Key to DC function is their positioning at sites of pathogen entry, and their abilities to selectively capture foreign antigens and promptly engage T cells. Focusing on conventional DC2 (cDC2), we discuss the contribution of chemoattractant receptors (EBI2 or GPR183, S1PR1, and CCR7) and integrins to cDC2 positioning and function. We give particular attention to a newly identified role in cDC2 for adhesion G-protein coupled receptor E5 (Adgre5 or CD97) and its ligand CD55, detailing how this mechanosensing system contributes to splenic cDC2 positioning and homeostasis. Additional roles of CD97 in the immune system are reviewed. The ability of cDC2 to be activated by circulating missing self-CD47 cells and to integrate multiple red blood cell (RBC)-derived inputs is discussed. Finally, we describe the process of activated cDC2 migration to engage and prime helper T cells. Throughout the review, we consider the insights into cDC function in the spleen that have emerged from imaging studies.


Asunto(s)
Células Dendríticas , Bazo , Antígenos , Homeostasis , Humanos , Ligandos
18.
Plant J ; 117(1): 33-52, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37731059

RESUMEN

Chromatin in eukaryotes folds into a complex three-dimensional (3D) structure that is essential for controlling gene expression and cellular function and is dynamically regulated in biological processes. Studies on plant phosphorus signaling have concentrated on single genes and gene interactions. It is critical to expand the existing signaling pathway in terms of its 3D structure. In this study, low-Pi treatment led to greater chromatin volume. Furthermore, low-Pi stress increased the insulation score and the number of TAD-like domains, but the effects on the A/B compartment were not obvious. The methylation levels of target sites (hereafter as RdDM levels) peaked at specific TAD-like boundaries, whereas RdDM peak levels at conserved TAD-like boundaries shifted and decreased sharply. The distribution pattern of RdDM sites originating from the Helitron transposons matched that of genome-wide RdDM sites near TAD-like boundaries. RdDM pathway genes were upregulated in the middle or early stages and downregulated in the later stages under low-Pi conditions. The RdDM pathway mutant ddm1a showed increased tolerance to low-Pi stress, with shortened and thickened roots contributing to higher Pi uptake from the shallow soil layer. ChIP-seq results revealed that ZmDDM1A could bind to Pi- and root development-related genes. Strong associations were found between interacting genes in significantly different chromatin-interaction regions and root traits. These findings not only expand the mechanisms by which plants respond to low-Pi stress through the RdDM pathway but also offer a crucial framework for the analysis of biological issues using 3D genomics.


Asunto(s)
Cromatina , Zea mays , Cromatina/genética , Zea mays/genética , Metilación de ADN , Ensamble y Desensamble de Cromatina/genética , Silenciador del Gen , Regulación de la Expresión Génica de las Plantas
19.
Artículo en Inglés | MEDLINE | ID: mdl-38592427

RESUMEN

The current CAR-T cell therapy products have been hampered in their druggability due to the personalized preparation required, unclear pharmacokinetic characteristics, and unpredictable adverse reactions. Enabling standardized manufacturing and having clear efficacy and pharmacokinetic characteristics are prerequisites for ensuring the effective practicality of CAR-T cell therapy drugs. This review provides a broad overview of the different approaches for controlling behaviors of CAR-T cells in vivo. The utilization of genetically modified vectors enables in vivo production of CAR-T cells, thereby abbreviating or skipping the lengthy in vitro expansion process. By equipping CAR-T cells with intricately designed control elements, using molecule switches or small-molecule inhibitors, the control of CAR-T cell activity can be achieved. Moreover, the on-off control of CAR-T cell activity would yield potential gains in phenotypic remodeling. These methods provide beneficial references for the future development of safe, controllable, convenient, and suitable for standardized production of CAR-T cell therapy products.

20.
PLoS Pathog ; 19(8): e1011594, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37611054

RESUMEN

Treponema pallidum (Tp) has a well-known ability to evade the immune system and can cause neurosyphilis by invading the central nervous system (CNS). Microglia are resident macrophages of the CNS that are essential for host defense against pathogens, this study aims to investigate the interaction between Tp and microglia and the potential mechanism. Here, we found that Tp can exert significant toxic effects on microglia in vivo in Tg (mpeg1: EGFP) transgenic zebrafish embryos. Single-cell RNA sequencing results showed that Tp downregulated autophagy-related genes in human HMC3 microglial cells, which is negatively associated with apoptotic gene expression. Biochemical and cell biology assays further established that Tp inhibits microglial autophagy by interfering with the autophagosome-lysosome fusion process. Transcription factor EB (TFEB) is a master regulator of lysosome biogenesis, Tp activates the mechanistic target of rapamycin complex 1 (mTORC1) signaling to inhibit the nuclear translocation of TFEB, leading to decreased lysosomal biogenesis and accumulated autophagosome. Importantly, the inhibition of autophagosome formation reversed Tp-induced apoptosis and promoted microglial clearance of Tp. Taken together, these findings show that Tp blocks autophagic flux by inhibiting TFEB-mediated lysosomal biosynthesis in human microglia. Autophagosome accumulation was demonstrated to be a key mechanism underlying the effects of Tp in promoting apoptosis and preventing itself from clearing by human microglia. This study offers novel perspectives on the potential mechanism of immune evasion employed by Tp within CNS. The results not only establish the pivotal role of autophagy dysregulation in the detrimental effects of Tp on microglial cells but also bear considerable implications for the development of therapeutic strategies against Tp, specifically involving mTORC1 inhibitors and autophagosome formation inhibitors, in the context of neurosyphilis patients.


Asunto(s)
Microglía , Neurosífilis , Humanos , Animales , Treponema pallidum/genética , Pez Cebra , Autofagia , Apoptosis
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