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1.
Commun Biol ; 7(1): 737, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890455

RESUMO

Muscle invasive bladder cancer (MIBC) is a molecularly diverse disease with varied clinical outcomes. Molecular studies typically employ bulk sequencing analysis, giving a transcriptomic snapshot of a section of the tumour. However, tumour tissues are not homogeneous, but are composed of distinct compartments such as the tumour and stroma. To investigate the molecular profiles of bladder cancer, whilst also maintaining the spatial complexity of the tumours, we employed whole transcriptome Digital Spatial Profiling (DSP). With this method we generated a dataset of transcriptomic profiles of tumour epithelium, stroma, and immune infiltrate. With these data we investigate the spatial relationship of molecular subtype signatures and ligand signalling events. We find that Basal/Squamous and Classical subtypes are mostly restricted to tumour regions, while the stroma-rich subtype signatures are abundant within the stroma itself. Additionally, we identify ligand signalling events occurring between tumour, stroma, and immune infiltrate regions, such as immune infiltrate derived GPNMB, which was highly correlated with VEGFA expression within the tumour. These findings give us new insights into the diversity of MIBC at a molecular level and provide a dataset with detailed spatial information that was not available before in bladder cancer research.


Assuntos
Microambiente Tumoral , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Microambiente Tumoral/genética , Invasividade Neoplásica , Perfilação da Expressão Gênica , Transcriptoma , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais
2.
RSC Chem Biol ; 5(3): 167-188, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38456038

RESUMO

In structural terms, the sialic acids are a large family of nine carbon sugars based around an alpha-keto acid core. They are widely spread in nature, where they are often found to be involved in molecular recognition processes, including in development, immunology, health and disease. The prominence of sialic acids in infection is a result of their exposure at the non-reducing terminus of glycans in diverse glycolipids and glycoproteins. Herein, we survey representative aspects of sialic acid structure, recognition and exploitation in relation to infectious diseases, their diagnosis and prevention or treatment. Examples covered span influenza virus and Covid-19, Leishmania and Trypanosoma, algal viruses, Campylobacter, Streptococci and Helicobacter, and commensal Ruminococci.

3.
Proc Natl Acad Sci U S A ; 120(49): e2309077120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011551

RESUMO

Human cytomegalovirus (HCMV) is a paradigm of pathogen immune evasion and sustains lifelong persistent infection in the face of exceptionally powerful host immune responses through the concerted action of multiple immune-evasins. These reduce NK cell activation by inhibiting ligands for activating receptors, expressing ligands for inhibitory receptors, or inhibiting synapse formation. However, these functions only inhibit direct interactions with the infected cell. To determine whether the virus also expresses soluble factors that could modulate NK function at a distance, we systematically screened all 170 HCMV canonical protein-coding genes. This revealed that UL4 encodes a secreted and heavily glycosylated protein (gpUL4) that is expressed with late-phase kinetics and is capable of inhibiting NK cell degranulation. Analyses of gpUL4 binding partners by mass spectrometry identified an interaction with TRAIL. gpUL4 bound TRAIL with picomolar affinity and prevented TRAIL from binding its receptor, thus acting as a TRAIL decoy receptor. TRAIL is found in both soluble and membrane-bound forms, with expression of the membrane-bound form strongly up-regulated on NK cells in response to interferon. gpUL4 inhibited apoptosis induced by soluble TRAIL, while also binding to the NK cell surface in a TRAIL-dependent manner, where it blocked NK cell degranulation and cytokine secretion. gpUL4 therefore acts as an immune-evasin by inhibiting both soluble and membrane-bound TRAIL and is a viral-encoded TRAIL decoy receptor. Interestingly, gpUL4 could also suppress NK responses to heterologous viruses, suggesting that it may act as a systemic virally encoded immunosuppressive agent.


Assuntos
Citomegalovirus , Células Matadoras Naturais , Humanos , Citomegalovirus/fisiologia , Evasão da Resposta Imune , Glicoproteínas/metabolismo , Apoptose
4.
Angew Chem Int Ed Engl ; 62(26): e202304303, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37130008

RESUMO

One striking feature of enzyme is its controllable ability to trap substrates via synergistic or cooperative binding in the enzymatic pocket, which renders the shape-selectivity of product by the confined spatial environment. The success of shape-selective catalysis relies on the ability of enzyme to tune the thermodynamics and kinetics for chemical reactions. In emulation of enzyme's ability, we showcase herein a targeting strategy with the substrate being anchored on the internal pore wall of metal-organic frameworks (MOFs), taking full advantage of the sterically kinetic control to achieve shape-selectivity for the reactions. For this purpose, a series of binding site-accessible metal metalloporphyrin-frameworks (MMPFs) have been investigated to shed light on the nature of enzyme-mimic catalysis. They exhibit a different density of binding sites that are well arranged into the nanospace with corresponding distances of opposite binding sites. Such a structural specificity results in a facile switch in selectivity from an exclusive formation of the thermodynamically stable product to the kinetic product. Thus, the proposed targeting strategy, based on the combination of porous materials and binding events, paves a new way to develop highly efficient heterogeneous catalysts for shifting selectivity.


Assuntos
Metaloporfirinas , Metaloporfirinas/química , Espaços Confinados , Cinética , Sítios de Ligação , Catálise
5.
ACS Nano ; 17(11): 10589-10597, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37186946

RESUMO

A persistent lack of detailed and quantitative structural analysis of these hierarchical carbon nanotube (CNT) ensembles precludes establishing processing-structure-property relationships that are essential to enhance macroscale performance (e.g., in mechanical, electrical, thermal applications). Here, we use scanning transmission X-ray microscopy (STXM) to analyze the hierarchical, twisted morphology of dry-spun CNT yarns and their composites, quantifying key structural characteristics such as density, porosity, alignment, and polymer loading. As the yarn twist density increases (15,000 to 150,000 turns per meter), the yarn diameter decreased (4.4-1.4 µm) and density increased (0.55-1.26 g·cm-3), as intuitively expected. Yarn density, ρ, ubiquitously scaled with diameter d according to ρ ∼ d-2 for all parameters studied here. Spectromicroscopy probes with 30 nm resolution and elemental specificity were employed to analyze the radial and longitudinal distribution of the oxygen-containing polymer content (∼30% weight fraction), demonstrating nearly perfect filling of the voids between CNTs with a vapor-phase polymer coating and cross-linking process. These quantitative correlations highlight the intimate connections between processing conditions and yarn structure with important implications for translating the nanoscale properties of CNTs to the macroscale.

6.
Mol Ther Oncolytics ; 29: 4-14, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36969560

RESUMO

Vesiculoviruses are attractive oncolytic virus platforms due to their rapid replication, appreciable transgene capacity, broad tropism, limited preexisting immunity, and tumor selectivity through type I interferon response defects in malignant cells. We developed a synthetic chimeric virus (VMG) expressing the glycoprotein (G) from Morreton virus (MorV) and utilizing the remaining structural genes from vesicular stomatitis virus (VSV). VMG exhibited in vitro efficacy by inducing oncolysis in a broad range of sarcoma subtypes across multiple species. Notably, all cell lines tested showed the ability of VMG to yield productive infection with rapid replication kinetics and induction of apoptosis. Furthermore, pilot safety evaluations of VMG in immunocompetent, non-tumor-bearing mice showed an absence of toxicity with intranasal doses as high as 1e10 50% tissue culture infectious dose (TCID50)/kg. Locoregional administration of VMG in vivo resulted in tumor reduction in an immunodeficient Ewing sarcoma xenograft at doses as low as 2e5 TCID50. In a murine syngeneic fibrosarcoma model, while no tumor inhibition was achieved with VMG, there was a robust induction of CD8+ T cells within the tumor. The studies described herein establish the promising potential for VMG to be used as a novel oncolytic virotherapy platform with anticancer effects in sarcoma.

9.
Nanoscale Horiz ; 8(3): 377-382, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36651292

RESUMO

Glycoforms (and other post-translational modifications) of otherwise identical proteins can indicate pathogenesis/disease state and hence new tools to detect and sense a protein's glycosylation status are essential. Antibody-based assays against specific protein sequences do not typically discriminate between glycoforms. Here we demonstrate a 'sandwich' bio-assay approach, whereby antibodies immobilised onto biolayer interferometry sensors first select proteins, and then the specific glycoform is identified using gold nanoparticles functionalised with lectins which provide signal enhancement. The nanoparticles significantly enhance the signal relative to lectins alone, allowing glycoform specific detection as low as 0.04 µg mL-1 (1.4 nM) in buffer, and crucially there is no need for an enrichment step and all steps can be automated. Proof of concept is demonstrated using prostate specific antigen: a biomarker for prostate cancer, where glycoform analysis could distinguish between cancerous and non-cancerous status, rather than only detecting overall protein concentration.


Assuntos
Lectinas , Nanopartículas Metálicas , Humanos , Masculino , Anticorpos , Glicosilação , Ouro , Lectinas/metabolismo , Neoplasias da Próstata/diagnóstico , Antígeno Prostático Específico/análise
10.
Hepatology ; 77(6): 1943-1957, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36052732

RESUMO

BACKGROUND: Morreton virus (MORV) is an oncolytic Vesiculovirus , genetically distinct from vesicular stomatitis virus (VSV). AIM: To report that MORV induced potent cytopathic effects (CPEs) in cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC) in vitro models. APPROACH AND RESULTS: In preliminary safety analyses, high intranasal doses (up to 10 10 50% tissue culture infectious dose [TCID 50 ]) of MORV were not associated with significant adverse effects in immune competent, non-tumor-bearing mice. MORV was shown to be efficacious in a Hep3B hepatocellular cancer xenograft model but not in a CCA xenograft HuCCT1 model. In an immune competent, syngeneic murine CCA model, single intratumoral treatments with MORV (1 × 10 7 TCID 50 ) triggered a robust antitumor immune response leading to substantial tumor regression and disease control at a dose 10-fold lower than VSV (1 × 10 8 TCID 50 ). MORV led to increased CD8 + cytotoxic T cells without compensatory increases in tumor-associated macrophages and granulocytic or monocytic myeloid-derived suppressor cells. CONCLUSIONS: Our findings indicate that wild-type MORV is safe and can induce potent tumor regression via immune-mediated and immune-independent mechanisms in HCC and CCA animal models without dose limiting adverse events. These data warrant further development and clinical translation of MORV as an oncolytic virotherapy platform.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia Viral Oncolítica , Camundongos , Humanos , Animais , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Vesiculovirus , Modelos Animais de Doenças , Linhagem Celular Tumoral
11.
Npj Viruses ; 1(1): 1, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38665237

RESUMO

Human adenoviruses (HAdV) are widespread pathogens causing usually mild infections. The Species D (HAdV-D) cause gastrointestinal tract infections and epidemic keratoconjunctivitis (EKC). Despite being significant pathogens, knowledge around HAdV-D mechanism of cell infection is lacking. Sialic acid (SA) usage has been proposed as a cell infection mechanism for EKC causing HAdV-D. Here we highlight an important role for SA engagement by many HAdV-D. We provide apo state crystal structures of 7 previously undetermined HAdV-D fiber-knob proteins, and structures of HAdV-D25, D29, D30 and D53 fiber-knob proteins in complex with SA. Biologically, we demonstrate that removal of cell surface SA reduced infectivity of HAdV-C5 vectors pseudotyped with HAdV-D fiber-knob proteins, whilst engagement of the classical HAdV receptor CAR was variable. Our data indicates variable usage of SA and CAR across HAdV-D. Better defining these interactions will enable improved development of antivirals and engineering of the viruses into refined therapeutic vectors.

14.
Nat Commun ; 13(1): 6626, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333371

RESUMO

Tropical cyclone rapid intensification events often cause destructive hurricane landfalls because they are associated with the strongest storms and forecasts with the highest errors. Multi-decade observational datasets of tropical cyclone behavior have recently enabled documentation of upward trends in tropical cyclone rapid intensification in several basins. However, a robust anthropogenic signal in global intensification trends and the physical drivers of intensification trends have yet to be identified. To address these knowledge gaps, here we compare the observed trends in intensification and tropical cyclone environmental parameters to simulated natural variability in a high-resolution global climate model. In multiple basins and the global dataset, we detect a significant increase in intensification rates with a positive contribution from anthropogenic forcing. Furthermore, thermodynamic environments around tropical cyclones have become more favorable for intensification, and climate models show anthropogenic warming has significantly increased the probability of these changes.


Assuntos
Tempestades Ciclônicas , Probabilidade
15.
RSC Adv ; 12(51): 33080-33090, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36425181

RESUMO

Glycan-lectin interactions play essential roles in biology; as the site of attachment for pathogens, cell-cell communication, and as crucial players in the immune system. Identifying if a new glycan (natural or unnatural) binds a protein partner, or if a new protein (or mutant) binds a glycan remains a non-trivial problem, with few accessible or low-cost tools available. Micro-arrays allow for the interrogation of 100's of glycans but are not widely available in individual laboratories. Biophysical techniques such as isothermal titration calorimetry, surface plasmon resonance spectrometry, biolayer interferometry and nuclear magnetic resonance spectroscopy all provide detailed understanding of glycan binding but are relatively expensive. Glycosylated plasmonic nanoparticles based on gold cores with polymeric tethers have emerged as biosensors to detect glycan-protein binding, based on colourimetric (red to blue) outputs which can be easily interpreted by a simple UV-visible spectrometer or by eye. Despite the large number of reports there are no standard protocols for each system or recommended start points, to allow a new user to deploy this technology. Here we explore the key parameters of nanoparticle size, polymeric tether length and gold concentration to provide some guidelines for how polymer-tethered glycosylated gold nanoparticles can be used to probe a new glycan/protein interactions, with minimal optimisation barriers. This work aimed to remove the need to explore chemical and nanoparticle space and hence remove a barrier for other users when deploying this system. We show that the concentration of the gold core is crucial to balance strong responses versus false positives and recommend a gold core size and polymer tether length which balances sufficient colloidal stability and output. Whilst subtle differences between glycans/lectins will impact the outcomes, these parameters should enable a lab user to quickly evaluate binding using minimal quantities of the glycan and lectin, to select candidates for further study.

16.
Biomacromolecules ; 23(12): 5285-5296, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36441868

RESUMO

Ice binding proteins (IBP) have evolved to limit the growth of ice but also to promote ice formation by ice-nucleating proteins (INPs). IBPs, which modulate these seemingly distinct processes, often have high sequence similarities, and molecular size/assembly is hypothesized to be a crucial determinant. There are only a few synthetic materials that reproduce INP function, and rational design of ice nucleators has not been achieved due to outstanding questions about the mechanisms of ice binding. Poly(vinyl alcohol) (PVA) is a water-soluble synthetic polymer well known to effectively block ice recrystallization, by binding to ice. Here, we report the synthesis of a polymeric ice nucleator, which mimics the dense assembly of IBPs, using confined ice-binding polymers in a high-molar-mass molecular bottlebrush. Poly(vinyl alcohol)-based molecular bottlebrushes with different side-chain densities were synthesized via a combination of ring-opening metathesis polymerization (ROMP) and reversible addition-fragmentation chain-transfer (RAFT) polymerization, using "grafting-to" and "grafting-through" approaches. The facile preparation of the PVA bottlebrushes was performed via selective hydrolysis of the acetate of the poly(vinyl acetate) (PVAc) side chains of the PVAc bottlebrush precursors. Ice-binding polymer side-chain density was shown to be crucial for nucleation activity, with less dense brushes resulting in colder nucleation than denser brushes. This bio-inspired approach provides a synthetic framework for probing heterogeneous ice nucleation and a route toward defined synthetic nucleators for biotechnological applications.


Assuntos
Gelo , Álcool de Polivinil , Álcool de Polivinil/química , Polimerização , Polímeros/química , Peso Molecular
17.
Chem Soc Rev ; 51(16): 7238-7259, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35894819

RESUMO

Current point-of-care lateral flow immunoassays, such as the home pregnancy test, rely on proteins as detection units (e.g. antibodies) to sense for analytes. Glycans play a fundamental role in biological signalling and recognition events such as pathogen adhesion and hence they are promising future alternatives to antibody-based biosensing and diagnostics. Here we introduce the potential of glycans coupled to gold nanoparticles as recognition agents for lateral flow diagnostics. We first introduce the concept of lateral flow, including a case study of lateral flow use in the field compared to other diagnostic tools. We then introduce glycosylated materials, the affinity gains achieved by the cluster glycoside effect and the current use of these in aggregation based assays. Finally, the potential role of glycans in lateral flow are explained, and examples of their successful use given.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Anticorpos , Ouro , Imunoensaio , Sistemas Automatizados de Assistência Junto ao Leito
18.
JCO Precis Oncol ; 6: e2100274, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666960

RESUMO

PURPOSE: This investigation sought to evaluate the prognostic value of pretreatment of circulating tumor DNA (ctDNA) in metastatic biliary tract cancers (BTCs) treated with platinum-based first-line chemotherapy treatment. MATERIALS AND METHODS: We performed a retrospective analysis of 67 patients who underwent ctDNA testing before platinum-based chemotherapy for first-line treatment for metastatic BTC. For analysis, we considered the detected gene with highest variant allele frequency as the dominant clone allele frequency (DCAF). Results of ctDNA analysis were correlated with patients' demographics, progression-free survival (PFS), and overall survival (OS). RESULTS: The median age of patients was 67 (27-90) years. Fifty-four (80.6%) of 67 patients evaluated had intrahepatic cholangiocarcinoma; seven had extrahepatic cholangiocarcinoma, and six gallbladder cancers. Forty-six (68.6%) of the patients were treated with cisplatin plus gemcitabine, and 16.4% of patients received gemcitabine and other platinum (carboplatin or oxaliplatin) combinations, whereas 15% of patients were treated on a clinical trial with gemcitabine and cisplatin plus additional agents (CX4945, PEGPH20, or nab-paclitaxel). TP53, KRAS, FGFR2, ARID1A, STK11, and IDH1 were the genes with highest frequency as DCAF. The median DCAF was 3% (0%-97%). DCAF > 3% was associated with worse OS (median OS: 10.8 v 18.8 months, P = .032). Stratifying DCAF in quartiles, DCAF > 10% was significantly related to worse PFS (median PFS: 3 months, P = .014) and worse OS (median OS: 7.0 months, P = .001). Each 1% increase in ctDNA was associated with a hazard ratio of 13.1 in OS when adjusting for subtypes, metastatic sites, size of largest tumor, age, sex, and CA19-9. CONCLUSION: DCAF at diagnosis of advanced BTC can stratify patients who have worse outcomes when treated with upfront platinum-based chemotherapy. Each increase in %ctDNA decreases survival probabilities.


Assuntos
Neoplasias dos Ductos Biliares , Neoplasias do Sistema Biliar , Colangiocarcinoma , DNA Tumoral Circulante , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias do Sistema Biliar/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Cisplatino , Células Clonais/patologia , Frequência do Gene , Humanos , Platina/uso terapêutico , Estudos Retrospectivos
19.
ACS Macro Lett ; 11(3): 317-322, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35575357

RESUMO

The COVID-19 pandemic has highlighted the need for innovative biosensing, diagnostic, and surveillance platforms. Here we report that glycosylated, polymer-stabilized, gold nanorods can bind the SARS-CoV-2 spike protein and show correlation to the presence of SARS-CoV-2 in primary COVID-19 clinical samples. Telechelic polymers were prepared by reversible addition-fragmentation chain-transfer polymerization, enabling the capture of 2,3-sialyllactose and immobilization onto gold nanorods. Control experiments with a panel of lectins and a galactosamine-terminated polymer confirmed the selective binding. The glycosylated rods were shown to give dose-dependent responses against recombinant truncated SARS-CoV-2 spike protein, and the responses were further correlated using primary patient swab samples. The essentiality of the anisotropic particles for reducing the background interference is demonstrated. This highlights the utility of polymer tethering of glycans for plasmonic biosensors of infection.


Assuntos
COVID-19 , Nanotubos , COVID-19/diagnóstico , Ouro , Humanos , Pandemias , Polímeros , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo
20.
RSC Adv ; 12(6): 3721-3728, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35425363

RESUMO

Exceptionally coercive SmCo5 particles are produced through calcium vapor reduction of SmCo5O9 powders synthesized by flame spray pyrolysis. The resulting powders are composed of oblate hexagonal particles approximately 2 microns across with smooth surfaces. This microstructure yields record-breaking room temperature coercivity H c,i >80 kOe, or >60 kOe when combined with advanced manufacturing approaches such as electrophoretic deposition or molding with tetraglyme inks. These techniques enable straightforward low-loss fabrication of bulk parts. The high coercivity is extremely robust at elevated temperatures, exceeding 10 kOe even at 600 °C. The oxide precursor approach removes the need for strict environmental control during synthesis that is common to other nanoparticle-based routes and can readily be scaled to kilogram quantities of feedstock production. Magnet powders produced by calcium vapor reduction can thus function as the building blocks for traditional or advanced manufacturing techniques, while the high coercivity enables consistent performance across a wide range of temperatures.

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