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1.
Blood ; 143(22): 2284-2299, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38457355

RESUMO

ABSTRACT: Epigenetic modulation of the cell-intrinsic immune response holds promise as a therapeutic approach for leukemia. However, current strategies designed for transcriptional activation of endogenous transposons and subsequent interferon type-I (IFN-I) response, show limited clinical efficacy. Histone lysine methylation is an epigenetic signature in IFN-I response associated with suppression of IFN-I and IFN-stimulated genes, suggesting histone demethylation as key mechanism of reactivation. In this study, we unveil the histone demethylase PHF8 as a direct initiator and regulator of cell-intrinsic immune response in acute myeloid leukemia (AML). Site-specific phosphorylation of PHF8 orchestrates epigenetic changes that upregulate cytosolic RNA sensors, particularly the TRIM25-RIG-I-IFIT5 axis, thereby triggering the cellular IFN-I response-differentiation-apoptosis network. This signaling cascade largely counteracts differentiation block and growth of human AML cells across various disease subtypes in vitro and in vivo. Through proteome analysis of over 200 primary AML bone marrow samples, we identify a distinct PHF8/IFN-I signature in half of the patient population, without significant associations with known clinically or genetically defined AML subgroups. This profile was absent in healthy CD34+ hematopoietic progenitor cells, suggesting therapeutic applicability in a large fraction of patients with AML. Pharmacological support of PHF8 phosphorylation significantly impairs the growth in samples from patients with primary AML. These findings provide novel opportunities for harnessing the cell-intrinsic immune response in the development of immunotherapeutic strategies against AML.


Assuntos
Epigênese Genética , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Animais , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Camundongos , Interferon Tipo I/metabolismo , Autorrenovação Celular , Regulação Leucêmica da Expressão Gênica
2.
Nature ; 588(7836): 157-163, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239784

RESUMO

Janus kinases (JAKs) mediate responses to cytokines, hormones and growth factors in haematopoietic cells1,2. The JAK gene JAK2 is frequently mutated in the ageing haematopoietic system3,4 and in haematopoietic cancers5. JAK2 mutations constitutively activate downstream signalling and are drivers of myeloproliferative neoplasm (MPN). In clinical use, JAK inhibitors have mixed effects on the overall disease burden of JAK2-mutated clones6,7, prompting us to investigate the mechanism underlying disease persistence. Here, by in-depth phosphoproteome profiling, we identify proteins involved in mRNA processing as targets of mutant JAK2. We found that inactivation of YBX1, a post-translationally modified target of JAK2, sensitizes cells that persist despite treatment with JAK inhibitors to apoptosis and results in RNA mis-splicing, enrichment for retained introns and disruption of the transcriptional control of extracellular signal-regulated kinase (ERK) signalling. In combination with pharmacological JAK inhibition, YBX1 inactivation induces apoptosis in JAK2-dependent mouse and primary human cells, causing regression of the malignant clones in vivo, and inducing molecular remission. This identifies and validates a cell-intrinsic mechanism whereby differential protein phosphorylation causes splicing-dependent alterations of JAK2-ERK signalling and the maintenance of JAK2V617F malignant clones. Therapeutic targeting of YBX1-dependent ERK signalling in combination with JAK2 inhibition could thus eradicate cells harbouring mutations in JAK2.


Assuntos
Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Neoplasias/genética , Neoplasias/patologia , Proteína 1 de Ligação a Y-Box/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Células Clonais/metabolismo , Células Clonais/patologia , Feminino , Xenoenxertos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Íntrons/genética , Janus Quinase 2/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Mutação , Transplante de Neoplasias , Neoplasias/tratamento farmacológico , Fosfoproteínas/análise , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteoma/análise , Proteômica , Splicing de RNA/genética , Indução de Remissão , Proteína 1 de Ligação a Y-Box/antagonistas & inibidores , Proteína 1 de Ligação a Y-Box/química
3.
Ann Neurol ; 96(1): 133-149, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38767023

RESUMO

OBJECTIVE: The aim of our study is to better understand the genetic architecture and pathological mechanisms underlying neurodegeneration in idiopathic Parkinson's disease (iPD). We hypothesized that a fraction of iPD patients may harbor a combination of common variants in nuclear-encoded mitochondrial genes ultimately resulting in neurodegeneration. METHODS: We used mitochondria-specific polygenic risk scores (mitoPRSs) and created pathway-specific mitoPRSs using genotype data from different iPD case-control datasets worldwide, including the Luxembourg Parkinson's Study (412 iPD patients and 576 healthy controls) and COURAGE-PD cohorts (7,270 iPD cases and 6,819 healthy controls). Cellular models from individuals stratified according to the most significant mitoPRS were subsequently used to characterize different aspects of mitochondrial function. RESULTS: Common variants in genes regulating Oxidative Phosphorylation (OXPHOS-PRS) were significantly associated with a higher PD risk in independent cohorts (Luxembourg Parkinson's Study odds ratio, OR = 1.31[1.14-1.50], p-value = 5.4e-04; COURAGE-PD OR = 1.23[1.18-1.27], p-value = 1.5e-29). Functional analyses in fibroblasts and induced pluripotent stem cells-derived neuronal progenitors revealed significant differences in mitochondrial respiration between iPD patients with high or low OXPHOS-PRS (p-values < 0.05). Clinically, iPD patients with high OXPHOS-PRS have a significantly earlier age at disease onset compared to low-risk patients (false discovery rate [FDR]-adj p-value = 0.015), similar to prototypic monogenic forms of PD. Finally, iPD patients with high OXPHOS-PRS responded more effectively to treatment with mitochondrially active ursodeoxycholic acid. INTERPRETATION: OXPHOS-PRS may provide a precision medicine tool to stratify iPD patients into a pathogenic subgroup genetically defined by specific mitochondrial impairment, making these individuals eligible for future intelligent clinical trial designs. ANN NEUROL 2024;96:133-149.


Assuntos
Mitocôndrias , Herança Multifatorial , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Doença de Parkinson/patologia , Herança Multifatorial/genética , Mitocôndrias/genética , Masculino , Feminino , Fosforilação Oxidativa , Pessoa de Meia-Idade , Idoso , Estudos de Casos e Controles , Células-Tronco Pluripotentes Induzidas , Predisposição Genética para Doença/genética , Estratificação de Risco Genético
4.
Methods ; 225: 28-37, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38485032

RESUMO

The manuscript presents the synthesis of a new di-chromene Schiff base (COM-CH) by combining 7-(diethylamino)-2-oxo-2H-chromene-3-carbohydrazide and 4-oxo-4H-chromene-3-carbaldehyde, and its characterization using various analytical techniques. The probe COM-CH functional group contains a hard donor atom that selectively complexes with Th4+ ions. This report investigated COM-CH's sensing ability towards Th4+ chromogenic and fluorogenic methods in ACN: H2O (8:2, v/v) with Th4+ ions. The COM-CH-Th4+ complex was excited at 430 nm, resulting in a bright emission band at 475 nm with a 45 nm Stokes shift. The COM-CH probe demonstrated the highest performance at pH 4.0 to 8.0, with a sensitivity of 18.7 nM. The complex formation of COM-CH with Th4+ was investigated using NMR, FTIR spectrometry, and density functional theory calculations. The COM-CH and Th4+ are bound with 2:1 stoichiometry and an association constant of 1.92 × 108 M-2. The probe's performance enabled the analysis of monazite sand and water samples for Th4+ content. The probe successfully detected Th4+ content in Caenorhabditis elegans, marking the first Th4+ detection in animal models.


Assuntos
Benzopiranos , Caenorhabditis elegans , Corantes Fluorescentes , Bases de Schiff , Animais , Bases de Schiff/química , Corantes Fluorescentes/química , Benzopiranos/química , Espectrometria de Fluorescência/métodos , Concentração de Íons de Hidrogênio , Imagem Óptica/métodos
5.
J Am Chem Soc ; 146(34): 23923-23932, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39148225

RESUMO

The strategic incorporation of fluorine atoms into molecules has become a cornerstone of modern pharmaceuticals, agrochemicals, and materials science. Herein, we have developed a covalent organic framework (COF)-based, robust photocatalyst that enables the photofluorodecarboxylation reaction of diverse carboxylic acids, producing alkyl fluorides with remarkable efficiency. The catalytic activity of an anthraquinone-based COF catalyst TpAQ outperforms other structurally analogous ß-ketoenamine COFs. Through comprehensive control experiments, photoluminescence, and electrochemical studies, we have elucidated the unique features of the material and the mechanistic pathway. This in-depth understanding has paved the way for optimizing the reaction conditions and achieving high yields of alkyl fluorides. The versatility of this protocol extends to a broad range of aliphatic acids with diverse functional groups and heterocycles. It also enabled the late-stage diversification of anti-inflammatory drugs and steroid derivatives. This opens up exciting possibilities for synthesizing novel pharmaceuticals and functionalized molecules. The methodology was also generalized to other light-mediated decarboxylative halogenation reactions. Furthermore, our method demonstrates scalability under both batch and continuous flow conditions, offering a promising approach for large-scale production. Additionally, the TpAQ catalyst exhibits exceptional durability and can be reused multiple times without significant activity loss (>80% yield after the eighth cycle), making it a sustainable and cost-effective solution. This work lays the foundation for developing efficient and sustainable light-driven synthesis methods using COFs as photocatalysts with potential applications beyond alkyl halide synthesis.

6.
Mol Med ; 30(1): 42, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519881

RESUMO

BACKGROUND: The formation and accumulation of cholesterol crystals (CC) at the lesion site is a hallmark of atherosclerosis. Although studies have shown the importance of vascular smooth muscle cells (VSMCs) in the disease atherosclerosis, little is known about the molecular mechanism behind the uptake of CC in VSMCs and their role in modulating immune response. METHODS: Human aortic smooth muscle cells were cultured and treated with CC. CC uptake and CC mediated signaling pathway and protein induction were studied using flow cytometry, confocal microscopy, western blot and Olink proteomics. Conditioned medium from CC treated VSMCs was used to study neutrophil adhesion, ROS production and phagocytosis. Neutrophil extracellular traps (NETs) formations were visualized using confocal microscopy. RESULTS: VSMCs and macrophages were found around CC clefts in human carotid plaques. CC uptake in VSMCs are largely through micropinocytosis and phagocytosis via PI3K-AkT dependent pathway. The uptake of CC in VSMCs induce the release inflammatory proteins, including IL-33, an alarming cytokine. Conditioned medium from CC treated VSMCs can induce neutrophil adhesion, neutrophil reactive oxygen species (ROS) and neutrophil extracellular traps (NETs) formation. IL-33 neutralization in conditioned medium from CC treated VSMCs inhibited neutrophil ROS production and NETs formation. CONCLUSION: We demonstrate that VSMCs due to its vicinity to CC clefts in human atherosclerotic lesion can modulate local immune response and we further reveal that the interaction between CC and VSMCs impart an inflammatory milieu in the atherosclerotic microenvironment by promoting IL-33 dependent neutrophil influx and NETs formation.


Assuntos
Aterosclerose , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/metabolismo , Citocinas/metabolismo , Músculo Liso Vascular/metabolismo , Interleucina-33 , Espécies Reativas de Oxigênio/metabolismo , Meios de Cultivo Condicionados/farmacologia , Meios de Cultivo Condicionados/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Aterosclerose/metabolismo , Colesterol/metabolismo , Miócitos de Músculo Liso/metabolismo
7.
Biochem Biophys Res Commun ; 739: 150578, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39178795

RESUMO

Beta-casomorphins (BCMs) are the bio-active peptides having opioid properties which are formed by the proteolytic digestion of ß-caseins in milk. BCM-7 forms when A1 milk is digested in the small intestine due to a histidine at the 67th position in ß-casein, unlike A2 milk, which has proline at this position and produces BCM-9. BCM-7 has further degraded into BCM-5 by the dipeptidyl peptidase-IV (DPP-IV) enzyme in the intestine. The opioid-like activity of BCM-7 is responsible for eliciting signaling pathways which enable a wide range of physiological effects. The aim of our study was to find out the differential role of BCMs (BCM-7, BCM-9 and BCM-5) on pancreatic ß-cell proliferation, insulin secretion, and opioid peptide binding receptors from ß-cells (RIN-5F cell line) in normal (5.5 mM) and high glucose (27.5 mM) concentrations. Our results showed that BCM-7/9/5 did not affect ß-cell viability, proliferation, and insulin secretion at normal glucose level. However, at higher glucose concentration, BCMs significantly protected ß-cells from glucotoxicity but did not affect the insulin secretion. Interestingly, in the presence of Mu-opioid peptide receptor antagonist CTOP, BCMs did not protect ß-cells from glucotoxicity. The results suggest that BCMs protect ß-cells from glucotoxicity via non-opioid mediated pathways because BCMs did not modulate the gene expression of the mu, kappa and delta opioid peptide receptors.

8.
Small ; 20(32): e2312229, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38488721

RESUMO

δ-MnO2 is a promising cathode material for aqueous aluminium-ion batteries (AAIBs) for its layered crystalline structure with large interlayer spacing. However, the excellent Al ion storage performance of δ-MnO2 cathode remains elusive due to the frustrating structural collapse during the intercalation of high ionic potential Al ion species. Here, it is discovered that introducing heterogeneous metal dopants with high bond dissociation energy when bonded to oxygen can significantly reinforce the structural stability of δ-MnO2 frameworks. This reinforcement translates to stable cycling properties and high specific capacity in AAIBs. Vanadium-doped δ-MnO2 (V-δ-MnO2) can deliver a high specific capacity of 518 mAh g-1 at 200 mA g-1 with remarkable cycling stability for 400 cycles and improved rate capabilities (468, 339, and 285 mAh g-1 at 0.5, 1, and 2 A g-1, respectively), outperforming other doped δ-MnO2 materials and the reported AAIB cathodes. Theoretical and experimental studies indicate that V doping can substantially improve the cohesive energy of δ-MnO2 lattices, enhance their interaction with Al ion species, and increase electrical conductivity, collectively contributing to high ion storage performance. These findings provide inspiration for the development of high-performance cathodes for battery applications.

9.
Small ; 20(24): e2306738, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38161257

RESUMO

Adoptive immunotherapy utilizing natural killer (NK) cells has demonstrated remarkable efficacy in treating hematologic malignancies. However, its clinical intervention for solid tumors is hindered by the limited expression of tumor-specific antigens. Herein, lipid-PEG conjugated hyaluronic acid (HA) materials (HA-PEG-Lipid) for the simple ex-vivo surface coating of NK cells is developed for 1) lipid-mediated cellular membrane anchoring via hydrophobic interaction and thereby 2) sufficient presentation of the CD44 ligand (i.e., HA) onto NK cells for cancer targeting, without the need for genetic manipulation. Membrane-engineered NK cells can selectively recognize CD44-overexpressing cancer cells through HA-CD44 affinity and subsequently induce in situ activation of NK cells for cancer elimination. Therefore, the surface-engineered NK cells using HA-PEG-Lipid (HANK cells) establish an immune synapse with CD44-overexpressing MIA PaCa-2 pancreatic cancer cells, triggering the "recognition-activation" mechanism, and ultimately eliminating cancer cells. Moreover, in mouse xenograft tumor models, administrated HANK cells demonstrate significant infiltration into solid tumors, resulting in tumor apoptosis/necrosis and effective suppression of tumor progression and metastasis, as compared to NK cells and gemcitabine. Taken together, the HA-PEG-Lipid biomaterials expedite the treatment of solid tumors by facilitating a sequential recognition-activation mechanism of surface-engineered HANK cells, suggesting a promising approach for NK cell-mediated immunotherapy.


Assuntos
Receptores de Hialuronatos , Ácido Hialurônico , Imunoterapia , Células Matadoras Naturais , Células Matadoras Naturais/imunologia , Receptores de Hialuronatos/metabolismo , Animais , Humanos , Imunoterapia/métodos , Ácido Hialurônico/química , Linhagem Celular Tumoral , Ligantes , Camundongos , Polietilenoglicóis/química , Neoplasias/terapia , Neoplasias/imunologia
10.
Small ; 20(15): e2306353, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37997226

RESUMO

Metal-organic frameworks (MOFs) represent a relatively new family of materials that attract lots of attention thanks to their unique features such as hierarchical porosity, active metal centers, versatility of linkers/metal nodes, and large surface area. Among the extended list of MOFs, Zr-based-MOFs demonstrate comparably superior chemical and thermal stabilities, making them ideal candidates for energy and environmental applications. As a Zr-MOF, NU-1000 is first synthesized at Northwestern University. A comprehensive review of various approaches to the synthesis of NU-1000 MOFs for obtaining unique surface properties (e.g., diverse surface morphologies, large surface area, and particular pore size distribution) and their applications in the catalysis (electro-, and photo-catalysis), CO2 reduction, batteries, hydrogen storage, gas storage/separation, and other environmental fields are presented. The review further outlines the current challenges in the development of NU-1000 MOFs and their derivatives in practical applications, revealing areas for future investigation.

11.
Blood ; 139(7): 1080-1097, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34695195

RESUMO

In an effort to identify novel drugs targeting fusion-oncogene-induced acute myeloid leukemia (AML), we performed high-resolution proteomic analysis. In AML1-ETO (AE)-driven AML, we uncovered a deregulation of phospholipase C (PLC) signaling. We identified PLCgamma 1 (PLCG1) as a specific target of the AE fusion protein that is induced after AE binding to intergenic regulatory DNA elements. Genetic inactivation of PLCG1 in murine and human AML inhibited AML1-ETO dependent self-renewal programs, leukemic proliferation, and leukemia maintenance in vivo. In contrast, PLCG1 was dispensable for normal hematopoietic stem and progenitor cell function. These findings are extended to and confirmed by pharmacologic perturbation of Ca++-signaling in AML1-ETO AML cells, indicating that the PLCG1 pathway poses an important therapeutic target for AML1-ETO+ leukemic stem cells.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia , Proteínas de Fusão Oncogênica/metabolismo , Fosfolipase C gama/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Animais , Autorrenovação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Células-Tronco Neoplásicas/metabolismo , Proteínas de Fusão Oncogênica/genética , Fosfolipase C gama/genética , Proteoma , Proteína 1 Parceira de Translocação de RUNX1/genética , Transcriptoma , Translocação Genética
12.
Chemistry ; : e202403251, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39380544

RESUMO

The electrochemical CO2 reduction reaction (CO2RR) occurs at the nanoscale interface of the electrode-electrolyte. Therefore, tailoring the interfacial properties in the interface microenvironment provides a powerful strategy to optimise the activity and selectivity of electrocatalysts towards the desired products. Here, the microenvironment at the electrode-electrolyte interface of the flow-through Ag-based hollow fibre gas diffusion electrode (Ag HFGDE) is modulated by introducing surfactant cetyltrimethylammonium bromide (CTAB) as the electrolyte additive. The porous hollow fibre configuration and gas penetration mode facilitate the CO2 mass transfer and the formation of the triple-phase interface. Through the ordered arrangement of hydrophobic long-alkyl chains, CTAB molecules at the electrode/electrolyte interface promoted CO2 penetration to active sites and repelled water to reduce the activity of competitive hydrogen evolution reaction (HER). By applying CTAB-containing catholyte, Ag HFGDE achieved a high CO Faradaic efficiency (FE) of over 95 % in a wide potential range and double the partial current density of CO. The enhancement of CO selectivity and suppression of hydrogen was attributed to the improvement of charge transfer and the CO2/H2O ratio enhancement. These findings highlight the importance of adjusting the local microenvironment to enhance the reaction kinetics and product selectivity in the electrochemical CO2 reduction reaction CO2RR.

13.
Mov Disord ; 39(7): 1217-1225, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38586902

RESUMO

BACKGROUND: Most Parkinson's disease (PD) loci have shown low prevalence in the Indian population, highlighting the need for further research. OBJECTIVE: The aim of this study was to characterize a novel phosphatase tensin homolog-induced serine/threonine kinase 1 (PINK1) mutation causing PD in an Indian family. METHODS: Exome sequencing of a well-characterized Indian family with PD. A novel PINK1 mutation was studied by in silico modeling using AlphaFold2, expression of mutant PINK1 in human cells depleted of functional endogenous PINK1, followed by quantitative image analysis and biochemical assessment. RESULTS: We identified a homozygous chr1:20648535-20648535 T>C on GRCh38 (p.F385S) mutation in exon 6 of PINK1, which was absent in 1029 genomes from India and in other known databases. PINK1 F385S lies within the highly conserved DFG motif, destabilizes its active state, and impairs phosphorylation of ubiquitin at serine 65 and proper engagement of parkin upon mitochondrial depolarization. CONCLUSIONS: We characterized a novel nonconservative mutation in the DFG motif of PINK1, which causes loss of its ubiquitin kinase activity and inhibition of mitophagy. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Linhagem , Proteínas Quinases , Humanos , Proteínas Quinases/genética , Doença de Parkinson/genética , Índia , Feminino , Masculino , Pessoa de Meia-Idade , Mutação com Perda de Função/genética , Adulto , Ubiquitina-Proteína Ligases/genética , Mutação/genética , Sequenciamento do Exoma , Mitofagia/genética
14.
Langmuir ; 40(10): 5106-5120, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38427698

RESUMO

The present study focuses on exploring the physical properties of lipid membranes based on the polyhydroxy oxanorbornane (PH-ONB) headgroup, designed as synthetic analogues of naturally occurring archaeal lipid membranes. Specifically, we study two variants of PH-ONB headgroup-based lipids differing in the number of hydroxy groups present in the headgroup, with one having two hydroxy groups (ONB-2OH) and the other having three (ONB-3OH). These lipids form stable bilayer membranes. The study begins with a comprehensive analysis of the fluorescence characteristics of nitrobenzoxadiazole (NBD)-tagged ONB-based lipids in different solvent environments and within a model lipid membrane 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Subsequently, the physical properties of the ONB-based membranes were examined by using an NBD-tagged ONB-based probe and a commonly used extrinsic 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescent probe. The steady-state and time-resolved fluorescence properties of the NBD-tagged ONB-based probe and DPH were used to compare the physical properties of the ONB-based membranes, including polarity, fluidity, phase transition, order, hydration, location, heterogeneity, and rotational diffusion. The solid gel to liquid crystalline phase transition temperatures of ONB-2OH and ONB-3OH lipid membranes are found to be (68 ± 1) °C and (74 ± 1) °C, respectively. The variation in organization (size), fluidity, and phase transition temperature of ONB-based lipid membranes is explained by the extent of hydrogen bonding interactions between lipid head groups. ONB-based membranes exhibit characteristics similar to those of phospholipid membranes and possess a notably high phase transition temperature. These properties make them a promising and cost-effective synthetic alternative to archaeal lipid membranes with a wide range of potential applications.


Assuntos
Corantes Fluorescentes , Fosfolipídeos , Corantes Fluorescentes/química , Fosfolipídeos/química , Fenômenos Químicos , Temperatura , Transição de Fase , Bicamadas Lipídicas/química , Fosfatidilcolinas/química
15.
Biomacromolecules ; 25(1): 222-237, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38130077

RESUMO

Phenylboronic acid (PBA) has been highly acknowledged as a significant cancer recognition moiety in sialic acid-overexpressing cancer cells. In this investigation, lipid-mediated biomaterial integrated PBA molecules onto the surface of natural killer (NK) cells to make a receptor-mediated immune cell therapeutic module. Therefore, a 1,2-distearoyl-sn-glycero-3-phosphorylethanolamine (DSPE) lipid-conjugated di-PEG-PBA (DSPEPEG-di(PEG-PBA) biomaterial was synthesized. The DSPEPEG-di(PEG-PBA) biomaterial exhibited a high affinity for sialic acid (SA), confirmed by fluorescence spectroscopy at pH 6.5 and 7.4. DSPEPEG-di(PEG-PBA) was successfully anchored onto NK cell surfaces (PBA-NK), and this biomaterial maintains intrinsic properties such as viability, ligand availability (FasL & TRAIL), and cytokine secretion response to LPS. The anticancer efficacy of PBA-NK cells was evaluated against 2D cancer cells (MDA-MB-231, HepG2, and HCT-116) and 3D tumor spheroids of MDA-MB-231 cells. PBA-NK cells exhibited greatly enhanced anticancer effects against SA-overexpressing cancer cells. Thus, PBA-NK cells represent a new anticancer strategy for cancer immunotherapy.


Assuntos
Ácido N-Acetilneuramínico , Neoplasias , Humanos , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Ácido N-Acetilneuramínico/uso terapêutico , Neoplasias/tratamento farmacológico , Células Matadoras Naturais , Lipídeos , Materiais Biocompatíveis/uso terapêutico
16.
Biomacromolecules ; 25(3): 1959-1971, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38379131

RESUMO

Triple-negative breast cancer (TNBC) presents treatment challenges due to a lack of detectable surface receptors. Natural killer (NK) cell-based adaptive immunotherapy is a promising treatment because of the characteristic anticancer effects of killing malignant cells directly by secreting cytokines and lytic granules. To maximize the cancer recognition ability of NK cells, biomaterial-mediated ex vivo cell surface engineering has been developed for sufficient cell membrane immobilization of tumor-targeting ligands via hydrophobic anchoring. In this study, we optimized amphiphilic balances of NK cell coating materials composed of CD44-targeting hyaluronic acid (HA)-poly(ethylene glycol) (PEG)-lipid to improve TNBC recognition and the anticancer effect. Changes in the modular design of our material by differentiating hydrophilic PEG length and incorporating lipid amount into HA backbones precisely regulated the amphiphilic nature of HA-PEG-lipid conjugates. The optimized biomaterial demonstrated improved anchoring into NK cell membranes and facilitating the surface presentation level of HA onto NK cell surfaces. This led to enhanced cancer targeting via increasing the formation of immune synapse, thereby augmenting the anticancer capability of NK cells specifically toward CD44-positive TNBC cells. Our approach addresses targeting ability of NK cell to solid tumors with a deficiency of surface tumor-specific antigens while offering a valuable material design strategy using amphiphilic balance in immune cell surface engineering techniques.


Assuntos
Ácido Hialurônico , Neoplasias de Mama Triplo Negativas , Humanos , Ácido Hialurônico/química , Linhagem Celular Tumoral , Materiais Biocompatíveis/farmacologia , Células Matadoras Naturais , Lipídeos , Receptores de Hialuronatos/metabolismo
17.
Eur J Haematol ; 112(3): 328-338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37899652

RESUMO

Allogeneic hematopoietic stem cell transplant (allo-HSCT) is increasingly being used in the United States (US) and across the world as a curative therapeutic option for patients with certain high-risk hematologic malignancies and non-malignant diseases. However, racial and ethnic disparities in utilization of the procedure and in outcome following transplant remain major problems. Racial and ethnic minority patients are consistently under-represented in the proportion of patients who undergo allo-HSCT in the US. The transplant outcomes in these patients are also inferior. The interrelated driving forces responsible for the differences in the utilization and transplant outcome of the medical intervention are socioeconomic status, complexity of the procedure, geographical barriers, and the results of differences in the genetics and comorbidities across different races. Bridging the disparity gaps is important not only to provide equity and inclusion in the utilization of this potentially life-saving procedure but also in ensuring that minority groups are well represented for research studies about allo-HSCT. This is required to determine interventions that may be more efficacious in particular racial and ethnic groups. Various strategies at the Federal, State, and Program levels have been designed to bridge the disparity gaps with varying successes. In this review paper, we will examine the disparities and discuss the strategies currently available to address the utilization and outcome gaps between patients of different races in the US.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Estados Unidos/epidemiologia , Etnicidade , Grupos Minoritários , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/terapia , Transplante Homólogo
18.
Int Microbiol ; 27(1): 227-238, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37269431

RESUMO

In this study, seven strains of Limosilactobacillus fermentum were isolated from an infant fecal sample and characterized using in vitro studies. Lactobacillus rhamnosus GG was used as a comparison because it is a well-documented commercial probiotic. The isolates were tested for attributes such as acid and phenol tolerance, bile salt hydrolase (BSH) activity, and antibiotic sensitivity. One isolate, L. fermentum FS-10, displayed enhanced cell surface hydrophobicity (> 85%) and mucin adhesion. Mucin-binding helps colonization in the gut. The immunomodulatory property of L. fermentum FS-10 was evaluated by determining the modulation of pro- and anti-inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10, and nitric oxide (NO) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions induced by lipopolysaccharide (LPS). L. fermentum FS-10 potently downregulated the expression of TNF-α and nitric oxide and upregulated IL-10 levels, indicating an anti-inflammatory response. Safety assessment of the strain revealed the absence of genes for virulence factors, toxin production, and antibiotic resistance, potentiating application as a probiotic strain.


Assuntos
Limosilactobacillus fermentum , Probióticos , Lactente , Humanos , Fator de Necrose Tumoral alfa , Óxido Nítrico , Anti-Inflamatórios/farmacologia , Mucinas , Probióticos/metabolismo
19.
J Org Chem ; 89(13): 9233-9242, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38912727

RESUMO

Enamines are difficult to prepare on the bench due to their instability, which results in side reactions, decompositions, poor yields, etc. Herein, we developed a simple and effective method for making bench-stable enamines using a very low amount of nickel catalyst loading. The deuterium exchange, competitive reaction, and radical clock experiment have all been found to favor the ionic mechanism of this alkene isomerization. Scale-up and [3 + 2] annulation reaction of enamines with activated cyclopropane to deliver cyclopentane derivatives have shown the value of this method in organic synthesis.

20.
Clin Exp Rheumatol ; 42(7): 1435-1441, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38372731

RESUMO

OBJECTIVES: GMCSF+T-cells may be involved in pathogenesis of rheumatoid arthritis (RA), and polyfunctionality may be a marker of pathogenicity. Although, higher frequencies of CD4+GMCSF+ T-cells have been reported, there are no data on CD8+GMCSF+ T-cells or polyfunctionality.Our objective was to enumerate frequencies of CD8+GMCSF+ T cells in RA blood and synovial fluid (SF), and assess their polyfunctionality, memory phenotype and cytotoxic ability. METHODS: This study included RA patients (blood samples,in some with paired synovial fluid (SF)), healthy controls (HC) (blood) and SpA patients (SF). In some RA patients' blood was sampled twice, before and 16-24 weeks after methotrexate (MTX) treatment. After mononuclear cell isolation from blood and SF, ex-vivo stimulation using PMA/Ionomycin was done, and cells were stained (surface and intracellular after permeabilisation/fixation). Subsequently, frequencies of GMCSF+CD8+ and CD4+ T-cells, polyfunctionality (TNFα, IFNγ, IL-17), phenotype (memory) and perforin/granzyme expression were assessed by flowcytometry. RESULTS: There was no significant difference in frequencies of GMCSF+CD8+ (3.7, 4.1%, p=0.540) or GMCSF+CD4+ T-cells (4.5, 5.2%, p=0.450) inblood of RA and HC. However, there was significant enrichment of both CD8+GMCSF+ (5.8, 3.9%, p=0.0045) and CD4+GMCSF+ (8.5, 4.5%, p=0.0008) T-cells inSF compared to blood in RA patients. Polyfunctional triple cytokine positive TNFα+IFNγ+GMCSF+CD8+T-cells (81, 36%, p=0.049) and CD4+T-cells (48, 32%, p=0.010) was also higher in SF compared to blood in RA. CD8+ T cells showed higher frequency of effector-memory phenotype and granzyme-B expression in RA-SF. On longitudinal follow-up, blood CD4+GMCSF+ T-cells significantly declined (4.6, 2.9%, p=0.0014) post-MTX. CONCLUSIONS: We report a novel finding of enrichment of CD8+GMCSF+ in addition to CD4+GMCSF+ T-cells in RA-SF. These cells showed higher polyfunctionality for TNFα and IFNγ, and effector memory phenotype suggesting their involvement in RA pathogenesis.


Assuntos
Artrite Reumatoide , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Interferon gama , Líquido Sinovial , Fator de Necrose Tumoral alfa , Humanos , Artrite Reumatoide/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Líquido Sinovial/imunologia , Líquido Sinovial/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Pessoa de Meia-Idade , Masculino , Feminino , Interferon gama/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Idoso , Fenótipo , Antirreumáticos/uso terapêutico , Memória Imunológica , Metotrexato/uso terapêutico , Granzimas/metabolismo , Interleucina-17/metabolismo , Perforina/metabolismo , Resultado do Tratamento , Células T de Memória/imunologia , Células T de Memória/metabolismo , Citotoxicidade Imunológica
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