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1.
Cell ; 187(1): 95-109.e26, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38181745

RESUMO

DddA-derived cytosine base editors (DdCBEs) and transcription activator-like effector (TALE)-linked deaminases (TALEDs) catalyze targeted base editing of mitochondrial DNA (mtDNA) in eukaryotic cells, a method useful for modeling of mitochondrial genetic disorders and developing novel therapeutic modalities. Here, we report that A-to-G-editing TALEDs but not C-to-T-editing DdCBEs induce tens of thousands of transcriptome-wide off-target edits in human cells. To avoid these unwanted RNA edits, we engineered the substrate-binding site in TadA8e, the deoxy-adenine deaminase in TALEDs, and created TALED variants with fine-tuned deaminase activity. Our engineered TALED variants not only reduced RNA off-target edits by >99% but also minimized off-target mtDNA mutations and bystander edits at a target site. Unlike wild-type versions, our TALED variants were not cytotoxic and did not cause developmental arrest of mouse embryos. As a result, we obtained mice with pathogenic mtDNA mutations, associated with Leigh syndrome, which showed reduced heart rates.


Assuntos
DNA Mitocondrial , Efetores Semelhantes a Ativadores de Transcrição , Animais , Humanos , Camundongos , Adenina , Citosina , DNA Mitocondrial/genética , Edição de Genes , RNA , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Engenharia de Proteínas
2.
Cell ; 185(10): 1764-1776.e12, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35472302

RESUMO

Mitochondrial DNA (mtDNA) editing paves the way for disease modeling of mitochondrial genetic disorders in cell lines and animals and also for the treatment of these diseases in the future. Bacterial cytidine deaminase DddA-derived cytosine base editors (DdCBEs) enabling mtDNA editing, however, are largely limited to C-to-T conversions in the 5'-TC context (e.g., TC-to-TT conversions), suitable for generating merely 1/8 of all possible transition (purine-to-purine and pyrimidine-to-pyrimidine) mutations. Here, we present transcription-activator-like effector (TALE)-linked deaminases (TALEDs), composed of custom-designed TALE DNA-binding arrays, a catalytically impaired, full-length DddA variant or split DddA originated from Burkholderia cenocepacia, and an engineered deoxyadenosine deaminase derived from the E. coli TadA protein, which induce targeted A-to-G editing in human mitochondria. Custom-designed TALEDs were highly efficient in human cells, catalyzing A-to-G conversions at a total of 17 target sites in various mitochondrial genes with editing frequencies of up to 49%.


Assuntos
DNA Mitocondrial , Doenças Mitocondriais , Animais , Sistemas CRISPR-Cas , Citosina/metabolismo , DNA Mitocondrial/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Edição de Genes , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Doenças Mitocondriais/genética , Purinas
3.
Plant Cell ; 35(4): 1222-1240, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36562145

RESUMO

Pollen tube attraction is a key event of sexual reproduction in flowering plants. In the ovule, two synergid cells neighboring the egg cell control pollen tube arrival via the active secretion of attractant peptides such as AtLURE1 and XIUQIU from the filiform apparatus (FA) facing toward the micropyle. Distinctive cell polarity together with longitudinal F-actin and microtubules are hallmarks of the synergid cell in various species, though the functions of these cellular structures are unclear. In this study, we used genetic and pharmacological approaches to indicate the roles of cytoskeletal components in FA formation and pollen tube guidance in Arabidopsis thaliana. Genetic inhibition of microtubule formation reduced invaginations of the plasma membrane but did not abolish micropylar AtLURE1.2 accumulation. By contrast, the expression of a dominant-negative form of ACTIN8 induced disorganization of the FA and loss of polar AtLURE1.2 distribution toward the FA. Interestingly, after pollen tube reception, F-actin became unclear for a few hours in the persistent synergid cell, which may be involved in pausing and resuming pollen tube attraction during early polytubey block. Our data suggest that F-actin plays a central role in maintaining cell polarity and in mediating male-female communication in the synergid cell.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Actinas/genética , Actinas/metabolismo , Tubo Polínico/genética , Tubo Polínico/metabolismo , Membrana Celular/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(28): e2302142120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399399

RESUMO

Harnessing the programmable nature of DNA origami for controlling structural features in crystalline materials affords opportunities to bring crystal engineering to a remarkable level. However, the challenge of crystallizing a single type of DNA origami unit into varied structural outcomes remains, given the requirement for specific DNA designs for each targeted structure. Here, we show that crystals with distinct equilibrium phases and shapes can be realized using a single DNA origami morphology with an allosteric factor to modulate the binding coordination. As a result, origami crystals undergo phase transitions from a simple cubic lattice to a simple hexagonal (SH) lattice and eventually to a face-centered cubic (FCC) lattice. After selectively removing internal nanoparticles from DNA origami building blocks, the body-centered tetragonal and chalcopyrite lattice are derived from the SH and FCC lattices, respectively, revealing another phase transition involving crystal system conversions. The rich phase space was realized through the de novo synthesis of crystals under varying solution environments, followed by the individual characterizations of the resulting products. Such phase transitions can lead to associated transitions in the shape of the resulting products. Hexagonal prism crystals, crystals characterized by triangular facets, and twinned crystals are observed to form from SH and FCC systems, which have not previously been experimentally realized by DNA origami crystallization. These findings open a promising pathway toward accessing a rich phase space with a single type of building block and wielding other instructions as tools to develop crystalline materials with tunable properties.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/química , Magnésio , DNA/química , Cristalização , Transição de Fase , Nanotecnologia , Conformação de Ácido Nucleico , Nanoestruturas/química
5.
Proc Natl Acad Sci U S A ; 119(26): e2122364119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35727971

RESUMO

Solar-driven bioelectrosynthesis represents a promising approach for converting abundant resources into value-added chemicals with renewable energy. Microorganisms powered by electrochemical reducing equivalents assimilate CO2, H2O, and N2 building blocks. However, products from autotrophic whole-cell biocatalysts are limited. Furthermore, biocatalysts tasked with N2 reduction are constrained by simultaneous energy-intensive autotrophy. To overcome these challenges, we designed a biohybrid coculture for tandem and tunable CO2 and N2 fixation to value-added products, allowing the different species to distribute bioconversion steps and reduce the individual metabolic burden. This consortium involves acetogen Sporomusa ovata, which reduces CO2 to acetate, and diazotrophic Rhodopseudomonas palustris, which uses the acetate both to fuel N2 fixation and for the generation of a biopolyester. We demonstrate that the coculture platform provides a robust ecosystem for continuous CO2 and N2 fixation, and its outputs are directed by substrate gas composition. Moreover, we show the ability to support the coculture on a high-surface area silicon nanowire cathodic platform. The biohybrid coculture achieved peak faradaic efficiencies of 100, 19.1, and 6.3% for acetate, nitrogen in biomass, and ammonia, respectively, while maintaining product tunability. Finally, we established full solar to chemical conversion driven by a photovoltaic device, resulting in solar to chemical efficiencies of 1.78, 0.51, and 0.08% for acetate, nitrogenous biomass, and ammonia, correspondingly. Ultimately, our work demonstrates the ability to employ and electrochemically manipulate bacterial communities on demand to expand the suite of CO2 and N2 bioelectrosynthesis products.


Assuntos
Dióxido de Carbono , Firmicutes , Fixação de Nitrogênio , Fotossíntese , Rodopseudomonas , Acetatos/metabolismo , Amônia , Dióxido de Carbono/metabolismo , Técnicas de Cocultura , Ecossistema , Firmicutes/crescimento & desenvolvimento , Firmicutes/metabolismo , Nitrogênio/metabolismo , Rodopseudomonas/crescimento & desenvolvimento , Rodopseudomonas/metabolismo
6.
BMC Biol ; 22(1): 105, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702628

RESUMO

BACKGROUND: Histone H3K4 tri-methylation (H3K4me3) catalyzed by Set1/COMPASS, is a prominent epigenetic mark found in promoter-proximal regions of actively transcribed genes. H3K4me3 relies on prior monoubiquitination at the histone H2B (H2Bub) by Rad6 and Bre1. Swd2/Cps35, a Set1/COMPASS component, has been proposed as a key player in facilitating H2Bub-dependent H3K4me3. However, a more comprehensive investigation regarding the relationship among Rad6, Swd2, and Set1 is required to further understand the mechanisms and functions of the H3K4 methylation. RESULTS: We investigated the genome-wide occupancy patterns of Rad6, Swd2, and Set1 under various genetic conditions, aiming to clarify the roles of Set1 and Rad6 for occupancy of Swd2. Swd2 peaks appear on both the 5' region and 3' region of genes, which are overlapped with its tightly bound two complexes, Set1 and cleavage and polyadenylation factor (CPF), respectively. In the absence of Rad6/H2Bub, Set1 predominantly localized to the 5' region of genes, while Swd2 lost all the chromatin binding. However, in the absence of Set1, Swd2 occupancy near the 5' region was impaired and rather increased in the 3' region. CONCLUSIONS: This study highlights that the catalytic activity of Rad6 is essential for all the ways of Swd2's binding to the transcribed genes and Set1 redistributes the Swd2 to the 5' region for accomplishments of H3K4me3 in the genome-wide level.


Assuntos
Histona-Lisina N-Metiltransferase , Histonas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Histonas/metabolismo , Histonas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Metilação , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética
7.
Nano Lett ; 24(39): 12263-12270, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39303068

RESUMO

A unary system is the most conceptually concise design for conducting self-assembly. However, in most DNA-guided self-assembly schemes, a unary system has rarely been adopted because of the inherent challenge of strictly decoupling the monomer synthesis process from the assembly process, which may directly lead to the inaccurate control over assembly. Herein, we provide a multi-stimulus-triggered assembly strategy based on the DNA origami structure, which allows the unary system to realize controllable crystallization and phase transition by exerting allosteric stimuli. We intentionally introduced a specific DNA stimulus to convert the self-aggregation of functionalized groups into the connection of nearby monomers, thus producing multidimensional high-quality crystals. Furthermore, this unary system can undergo a phase transition from simple cubic to face-centered cubic with the introduction of more cation stimuli. We believe that this dynamic stimulation strategy can offer a novel solution for fabricating materials with on-demand modulation.


Assuntos
DNA , Nanoestruturas , Transição de Fase , DNA/química , Nanoestruturas/química , Cristalização , Conformação de Ácido Nucleico , Nanotecnologia/métodos
8.
Cancer Sci ; 115(3): 989-1000, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38226451

RESUMO

Chemotherapy combined with debulking surgery is the standard treatment protocol for high-grade serous ovarian carcinoma (HGSOC). Nonetheless, a significant number of patients encounter relapse due to the development of chemotherapy resistance. To better understand and address this resistance, we conducted a comprehensive study investigating the transcriptional alterations at the single-cell resolution in tissue samples from patients with HGSOC, using single-cell RNA sequencing and T-cell receptor sequencing techniques. Our analyses unveiled notable changes in the tumor signatures after chemotherapy, including those associated with epithelial-mesenchymal transition and cell cycle arrest. Within the immune compartment, we observed alterations in the T-cell profiles, characterized by naïve or pre-exhausted populations following chemotherapy. This phenotypic change was further supported by the examination of adjoining T-cell receptor clonotypes in paired longitudinal samples. These findings underscore the profound impact of chemotherapy on reshaping the tumor landscape and the immune microenvironment. This knowledge may provide clues for the development of future therapeutic strategies to combat treatment resistance in HGSOC.


Assuntos
Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Linfócitos T/patologia , Receptores de Antígenos de Linfócitos T , Microambiente Tumoral
9.
Am J Physiol Gastrointest Liver Physiol ; 327(3): G405-G413, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38953836

RESUMO

Our prior study reveals that the distension-contraction profiles using high-resolution manometry impedance recordings can distinguish patients with dysphagia symptom but normal esophageal function testing ("functional dysphagia") from control subjects. The aim of this study was to determine the diagnostic value of the recording protocol used in our prior studies (10-mL swallows with subjects in the Trendelenburg position) against the standard clinical protocol (5-mL swallows with subjects in the supine position). We used advanced machine learning techniques and robust metrics for classification purposes. Studies were performed on 30 healthy subjects and 30 patients with functional dysphagia. A custom-built software was used to extract the relevant distension-contraction features of esophageal peristalsis. Ensemble methods, i.e., gradient boost, support vector machines (SVMs), and logit boost, were used as the primary machine learning algorithms. Although the individual contraction features were marginally different between the two groups, the distension features of peristalsis were significantly different. The receiver operating characteristic (ROC) curve values for the standard recording protocol and the distension features ranged from 0.74 to 0.82; they were significantly better for the protocol used in our prior studies, ranging from 0.81 to 0.91. The ROC curve values using three machine learning algorithms were far superior for the distension than the contraction features of esophageal peristalsis, revealing a value of 0.95 for the SVM algorithm. Current patient classification for esophageal motility disorders, based on the contraction phase of peristalsis, ignores a large number of patients who have an abnormality in the distension phase of peristalsis. Distension-contraction plots should be the standard for assessing esophageal peristalsis in clinical practice.NEW & NOTEWORTHY Our findings underscore the superiority of distension features over contraction metrics in diagnosing esophageal dysfunctions. By leveraging state-of-the-art machine learning techniques, our study highlights the diagnostic potential of distension-contraction plots of peristalsis. Implementation of these plots could significantly enhance the accuracy of identifying patients with esophageal motor disorders, advocating for their adoption as the standard in clinical practice.


Assuntos
Transtornos de Deglutição , Deglutição , Esôfago , Manometria , Peristaltismo , Humanos , Manometria/métodos , Peristaltismo/fisiologia , Masculino , Feminino , Esôfago/fisiologia , Esôfago/fisiopatologia , Pessoa de Meia-Idade , Adulto , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Idoso , Inteligência Artificial , Transtornos da Motilidade Esofágica/diagnóstico , Transtornos da Motilidade Esofágica/fisiopatologia , Aprendizado de Máquina , Contração Muscular/fisiologia
10.
Anal Chem ; 96(1): 281-291, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38153251

RESUMO

Atherosclerosis (AS) is the root cause of cardiovascular diseases. Ferroptosis is characterized by highly iron-dependent lipid peroxidation and has been reported to play an important role in the pathogenesis of AS. Visualization of the ferroptosis process in atherosclerotic plaques is of great importance for diagnosing and treating AS. In this work, the rationally designed fluorescent probe FAS1 exhibited excellent advantages including large Stokes shift, sensitivity to environmental viscosity, good photostability, and improved water solubility. It also could co-locate with commercial lipid droplets (LDs) probes (BODIPY 493/503) well in RAW264.7 cells treated by the ferroptosis inducer. After self-assembly into nanoparticles and then encapsulation with macrophage membranes, the engineered FAS1@MM NPs could successfully target the atherosclerotic plaques in Western diet-induced apolipoprotein E knockout (ApoE-/-) mice and reveal the association of ferroptosis with AS through fluorescence imaging in vivo. This study may provide additional insights into the roles of ferroptosis in the diagnosis and treatment of AS.


Assuntos
Aterosclerose , Ferroptose , Placa Aterosclerótica , Camundongos , Animais , Placa Aterosclerótica/diagnóstico por imagem , Aterosclerose/metabolismo , Macrófagos/metabolismo , Membrana Celular/metabolismo
11.
Biochem Biophys Res Commun ; 735: 150796, 2024 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-39427377

RESUMO

Controlling the microenvironment surrounding the pluripotent stem cells (PSCs) is a pivotal strategy for regulating cellular differentiation. Surface nanotopography is one of the key factors influencing the lineage-specific differentiation of PSCs. However, much of the underlying mechanism remains unknown. In this study, we focused on the effects of gradient nanotopography on the differentiation of embryoid bodies (EBs). EBs were cultured on three differently sized nanopillar surfaces (Large, 280-360; Medium, 200-280; Small, 120-200 nm) for spontaneous cardiomyocyte differentiation without chemical stimuli. The large nanotopography significantly promoted cardiogenesis, with increased expression of cardiac markers such as α-MHC, cTnT, and cTnI, and redistributed vinculin expression to the contact area. In addition, the small and medium nanotopographies also influenced EB differentiation, affecting both cardiogenesis and hematopoiesis to varying degrees. The phosphorylation of focal adhesion kinase (FAK) decreased in the EBs on the large nanotopography compared to that in the EBs cultured on the flat surface. The gradient nanotopography with 280-360 nm nanopillars is beneficial for the cardiogenesis of EBs in a FAK-dependent manner. This study provides valuable insights into controlling stem cell differentiation through nanotopographical cues, thereby advancing our understanding of the microenvironmental regulation in stem cell-based cardiac tissue engineering.


Assuntos
Diferenciação Celular , Corpos Embrioides , Miócitos Cardíacos , Células-Tronco Pluripotentes , Transdução de Sinais , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Animais , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Organogênese
12.
Am J Gastroenterol ; 119(6): 1117-1125, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634559

RESUMO

INTRODUCTION: Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography (CT) and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. METHODS: Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal CT at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression. RESULTS: We enrolled 6,570 patients who underwent EGD and abdominal CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (hazard ratio: 3.22, 95% confidence interval: 1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated. DISCUSSION: Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.


Assuntos
Endoscopia do Sistema Digestório , Esofagite Péptica , Gordura Intra-Abdominal , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Gordura Intra-Abdominal/diagnóstico por imagem , Gordura Intra-Abdominal/patologia , Esofagite Péptica/diagnóstico por imagem , Esofagite Péptica/patologia , Endoscopia do Sistema Digestório/métodos , Fatores de Risco , Adulto , Obesidade Abdominal/complicações , Obesidade Abdominal/diagnóstico por imagem , Redes Neurais de Computação , Idoso , Estudos Retrospectivos , Índice de Gravidade de Doença
13.
Breast Cancer Res Treat ; 206(1): 31-44, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38743175

RESUMO

PURPOSE: This single-center, randomized, prospective, exploratory clinical trial was conducted to assess the clinical efficacy of an augmented reality (AR)-based breast cancer localization imaging solution for patients with breast cancer. METHODS: This clinical trial enrolled 20 women who were diagnosed with invasive breast cancer between the ages of 19 and 80, had a single lesion with a diameter ≥ 5 mm but ≤ 30 mm, had no metastases to other organs, and had not received prior chemotherapy. All patients underwent mammography, ultrasound, computed tomography, and magnetic resonance imaging for preoperative assessment. Patients were randomly assigned to ultrasound-guided skin marking localization (USL) and AR-based localization (ARL) groups (n = 10 in each group). Statistical comparisons between USL and ARL groups were made based on demographics, radiologic features, pathological outcomes, and surgical outcomes using chi-square and Student t-tests. RESULTS: Two surgeons performed breast-conserving surgery on 20 patients. Histopathologic evaluation of all patients confirmed negative margins. Two independent pathologists evaluated the marginal distances, and there were no intergroup differences in the readers' estimates (R1, 6.20 ± 4.37 vs. 5.04 ± 3.47, P = 0.519; R2, 5.10 ± 4.31 vs. 4.10 ± 2.38, P = 0.970) or the readers' average values (5.65 ± 4.19 vs. 4.57 ± 2.84, P = 0.509). In comparing the tumor plane area ratio, there was no statistically significant difference between the two groups in terms of either reader's mean values (R1, 15.90 ± 9.52 vs. 19.38 ± 14.05, P = 0.525; R2, 15.32 ± 9.48 vs. 20.83 ± 12.85, P = 0.290) or the overall mean values of two readers combined (15.56 ± 9.11 vs. 20.09 ± 13.38, P = 0.388). Convenience, safety, satisfaction, and reusability were all superior in the AR localization group (P < 0.001) based on the two surgeons' responses. CONCLUSION: AR localization is an acceptable alternative to ultrasound-guided skin marking with no significant differences in surgical outcomes.


Assuntos
Realidade Aumentada , Neoplasias da Mama , Mastectomia Segmentar , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Mastectomia Segmentar/métodos , Adulto , Idoso , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Mamografia/métodos , Idoso de 80 Anos ou mais , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Resultado do Tratamento
14.
Radiology ; 310(2): e231406, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38411517

RESUMO

Background Chimeric antigen receptor (CAR) T cells are a promising cancer therapy; however, reliable and repeatable methods for tracking and monitoring CAR T cells in vivo remain underexplored. Purpose To investigate direct and indirect imaging strategies for tracking the biodistribution of CAR T cells and monitoring their therapeutic effect in target tumors. Materials and Methods CAR T cells co-expressing a tumor-targeting gene (anti-CD19 CAR) and a human somatostatin receptor subtype 2 (hSSTr2) reporter gene were generated from human peripheral blood mononuclear cells. After direct labeling with zirconium 89 (89Zr)-p-isothiocyanatobenzyl-desferrioxamine (DFO), CAR T cells were intravenously injected into immunodeficient mice with a CD19-positive and CD19-negative human tumor xenograft on the left and right flank, respectively. PET/MRI was used for direct in vivo imaging of 89Zr-DFO-labeled CAR T cells on days 0, 1, 3, and 7 and for indirect cell imaging with the radiolabeled somatostatin receptor-targeted ligand gallium 68 (68Ga)-DOTA-Tyr3-octreotide (DOTATOC) on days 6, 9, and 13. On day 13, mice were euthanized, and tissues and tumors were excised. Results The 89Zr-DFO-labeled CAR T cells were observed on PET/MRI scans in the liver and lungs of mice (n = 4) at all time points assessed. However, they were not visualized in CD19-positive or CD19-negative tumors, even on day 7. Serial 68Ga-DOTATOC PET/MRI showed CAR T cell accumulation in CD19-positive tumors but not in CD19-negative tumors from days 6 to 13. Notably, 68Ga-DOTATOC accumulation in CD19-positive tumors was highest on day 9 (mean percentage injected dose [%ID], 3.7% ± 1.0 [SD]) and decreased on day 13 (mean %ID, 2.6% ± 0.7) in parallel with a decrease in tumor volume (day 9: mean, 195 mm3 ± 27; day 13: mean, 127 mm3 ± 43) in the group with tumor growth inhibition. Enhanced immunohistochemistry staining of cluster of differentiation 3 (CD3) and hSSTr2 was also observed in excised CD19-positive tumor tissues. Conclusion Direct and indirect cell imaging with PET/MRI enabled in vivo tracking and monitoring of CAR T cells in an animal model. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Bulte in this issue.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Animais , Camundongos , Xenoenxertos , Radioisótopos de Gálio , Receptores de Somatostatina , Leucócitos Mononucleares , Distribuição Tecidual , Tomografia por Emissão de Pósitrons , Imageamento por Ressonância Magnética , Modelos Animais de Doenças , Linfócitos T
15.
Small ; : e2405635, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39344596

RESUMO

The increasing incidence of serious bacterial keratitis, a sight-threatening condition often exacerbated by inadequate contact lens (CLs) care, highlights the need for innovative protective technology. This study introduces a long-lasting antibacterial, non-cytotoxic, transparent nanocoating for CLs via a solvent-free polymer deposition method, aiming to prevent bacterial keratitis. The nanocoating comprises stacked polymer films, with poly(dimethylaminomethyl styrene-co-ethylene glycol dimethacrylate) (pDE) as a biocompatible, antibacterial layer atop poly(2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane) (pV4D4) as an adhesion-promoting layer. The pD6E1-grafted (g)-pV4D4 film shows non-cytotoxicity toward two human cell lines and antibacterial activity of >99% against four bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), an antibiotic-resistant bacteria and Pseudomonas aeruginosa, which causes ocular diseases. Additionally, the film demonstrates long-lasting antibacterial activity greater than 96% against MRSA for 9 weeks in phosphate-buffered saline. To the best knowledge, this duration represents the longest reported long-term stability with less than 5% decay of antibacterial performance among contact-killing antibacterial coatings. The film exhibits exceptional mechanical durability, retaining its antibacterial activity even after 15 washing cycles. The pD6E1-g-pV4D4-coated CL maintains full optical transmittance compared to that of pristine CL. It is expected that the unprecedentedly prolonged antibacterial performance of the coating will significantly alleviate the risk of infection for long-term CL users.

16.
Chembiochem ; : e202400670, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365708

RESUMO

Over the last four decades, research on DNA as a functional material has primarily  focused on its predictable conformation and programmable interaction. However, its low energy consumption, high responsiveness and sensitivity also make it ideal for designing specific signaling pathways, and enabling the development of molecular computers. This review mainly discusses recent advancements  in the utilization of DNA nanotechnology for molecular computer, encompassing applications in storage, cryptography and logic circuits. It elucidates the challenges encountered in the application process and presents solutions exemplified by representative works. Lastly, it delineates the challenges and opportunities within this filed.

17.
J Transl Med ; 22(1): 995, 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39497094

RESUMO

BACKGROUND: Aerobic glycolysis is a tumor cell phenotype and a hallmark in cancer research. The alternative splicing of the pyruvate kinase M (PKM) gene regulates the expressions of PKM1/2 isoforms and the aerobic glycolysis of tumors. Polypyrimidine tract binding protein (PTBP1) is critical in this process; however, its impact and underlying mechanisms in colorectal cancer (CRC) remain unclear. This study aimed to investigate the role of PTBP1 crotonylation in CRC progression. METHODS: The crotonylation levels of PTBP1 in human CRC tissues and cell lines were analyzed using crotonylation proteomics and immunoprecipitation. The main crotonylation sites were identified by immunoprecipitation and immunofluorescent staining. The glycolytic capacities of CRC cells were evaluated by measuring the glucose uptake, lactate production, extracellular acidification rate, and glycolytic proton efflux rate. The role and mechanism of PTBP1 crotonylation in PKM alternative splicing were determined by Western blot, quantitative real-time PCR (RT-qPCR), RNA immunoprecipitation, and immunoprecipitation. The effects of PTBP1 crotonylation on the behaviors of CRC cells and CRC progression were assessed using CCK-8, colony formation, cell invasion, wound healing assays, xenograft model construction, and immunohistochemistry. RESULTS: The crotonylation level of PTBP1 was elevated in human CRC tissues compared to peritumor tissues. In CRC tissues and cells, PTBP1 was mainly crotonylated at K266 (PTBP1 K266-Cr), and lysine acetyltransferase 2B (KAT2B) acted as the crotonyltranferase. PTBP1 K266-Cr promoted glycolysis and lactic acid production, increasing the PKM2/PKM1 ratio in CRC tissues and cells. Mechanistically, PTBP1 K266-Cr enhanced the interaction of PTBP1 with heterogeneous nuclear ribonucleoprotein A1 and A2 (hnRNPA1/2), thus affecting the PKM alternative splicing. PTBP1 K266-Cr facilitated CRC cell proliferation, migration, and metastasis in vitro and in vivo. Pathologically, a high level of PTBP1 K266-Cr was associated with poor prognosis in CRC patients. CONCLUSIONS: Crotonylation of PTBP1 coordinates tumor cell glycolysis and promotes CRC progression by regulating PKM alternative splicing and increasing PKM2 expression.


Assuntos
Processamento Alternativo , Proteínas de Transporte , Neoplasias Colorretais , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Proteínas de Ligação a Hormônio da Tireoide , Hormônios Tireóideos , Regulação para Cima , Humanos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Processamento Alternativo/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Regulação para Cima/genética , Animais , Linhagem Celular Tumoral , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Hormônios Tireóideos/metabolismo , Camundongos Nus , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proliferação de Células , Masculino , Feminino , Camundongos , Glicólise/genética , Movimento Celular/genética , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade
18.
Artigo em Inglês | MEDLINE | ID: mdl-38180873

RESUMO

OBJECTIVE: Graves' disease (GD) is a major autoimmune thyroid disorder and associated with non-thyroidal autoimmune disease (NTAD). We aimed to investigate the risk of NTAD in patients with GD compared with age- and sex-matched controls and to evaluate whether the risk differs between individuals with or without Graves' ophthalmopathy (GO). METHODS: This was a retrospective cohort study using data from the Korean National Health Claims database. We included 77 401 patients with GD (2,310 with GO) and 77 401 age- and sex-matched controls. Risk of NTAD were compared between the entire cohort and within the GD cohort. RESULTS: During a mean follow-up period of 9 years, NTAD developed in 12 341 (16.1%) patients in the GD cohort. Risk for systemic lupus erythematosus (SLE) [adjusted hazard ratio (aHR):1.15, 95% confidence interval (CI): 1.02-1.29], vitiligo (aHR: 1.24, 95% CI: 1.10-1.40), and alopecia areata (aHR: 1.11, 95% CI: 1.10-1.40) were higher in the GD cohort than in the control cohort. In the GD cohort, risk for SLE (aHR: 1.60, 95% CI: 1.11-2.33), Sjogren's syndrome (aHR: 1.89, 95% CI: 1.30-2.74), and ankylosing spondylitis (aHR: 1.53, 95% CI: 1.08-2.17) were higher in the GO group than in the non-GO group. CONCLUSION: This study demonstrated an increased risk of SLE, vitiligo and alopecia areata in patient with GD. In the GD cohort, patients with GO had an increased risk of SLE, Sjogren's syndrome and ankylosing spondylitis. These findings suggest that importance of implementing a strategy for early detection of NTAD based on the presence of GO.

19.
Mol Phylogenet Evol ; 201: 108194, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276821

RESUMO

Our intensive surveys of wild drosophilids in East and Southeast Asia discovered a great species diversity (more than 100 putatively new species) of the genus Dichaetophora, which is currently comprised of 67 formally described species assigned into five species groups, i.e., agbo, tenuicauda, acutissima, sinensis and trilobita. In the present study, we delimited species from a huge amount of samples of Dichaetophora and allied taxa (the genus Mulgravea and the subgenus Dudaica of Drosophila) collected from a wide range of the Oriental and east Palearctic regions. We first sorted all specimens into morpho-species, and representative specimen(s) selected from each morpho-species were subjected to barcoding of COI (the cytochrome c oxidase subunit I gene) sequences. The applied ASAP (Assemble Species by Automatic Partitioning) analysis estimated a total of 166 to 168 MOTUs (molecular operational taxonomic units). Integrating this result with morphological evidence from re-examined, detailed structures of male terminalia, we recognized a total of 144 (109 new and 35 known) species in our sample. Out of them, 83 species representing the supraspecific taxa of Dichaetophora, Mulgravea and Dudaica were selected, along with 33 species from major genera and subgenera of Drosophila in the tribe Drosophilini, as in-group and four species from the tribe Colocasiomyini as out-group for phylogenetic reconstruction based on 12 nuclear gene markers. In the trees constructed by the maximum likelihood and Bayesian inference methods, the three focal taxa (i.e., Dichaetophora, Mulgravea and Dudaica) formed a clade provisionally called the "pan-Dichaetophora". Within this large clade, the agbo, tenuicauda, sinensis and trilobita groups of Dichaetophora, Mulgravea and Dudaica were recovered as monophyletic groups, but Dichaetophora and its acutissima group were regarded as paraphyletic. In addition, two clusters were recognized among ungrouped species of Dichaetophora. Thus, the present study has uncovered some issues concerning the taxonomy of the pan-Dichaetophora. Such issues will be addressed elsewhere in the phylogenetic reclassification of the pan-Dichaetophora, along with descriptions/redescriptions of a large number of new/known species delimited in the present study.

20.
Cancer Cell Int ; 24(1): 13, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184573

RESUMO

Gastric cancer remains a leading cause of cancer-related death worldwide, largely due to inadequate screening methods, late diagnosis, and limited treatment options. Liquid biopsy has emerged as a promising non-invasive approach for cancer screening and prognosis by detecting circulating tumor components like circulating tumor DNA (ctDNA) in the blood. Numerous gastric cancer-specific ctDNA biomarkers have now been identified. CtDNA analysis provides insight into genetic and epigenetic alterations in tumors, holding promise for predicting treatment response and prognosis in gastric cancer patients. This review summarizes current research on ctDNA biology and detection technologies, while highlighting clinical applications of ctDNA for gastric cancer diagnosis, prognosis, and guiding treatment decisions. Current challenges and future perspectives for ctDNA analysis are also discussed.

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