Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Antibodies (Basel) ; 12(4)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37873862

RESUMO

Antibody-drug conjugates (ADCs) constitute a rapidly expanding category of biopharmaceuticals that are reshaping the landscape of targeted chemotherapy. The meticulous process of selecting therapeutic targets, aided by specific monoclonal antibodies' high specificity for binding to designated antigenic epitopes, is pivotal in ADC research and development. Despite ADCs' intrinsic ability to differentiate between healthy and cancerous cells, developmental challenges persist. In this study, we present a rationalized pipeline encompassing the initial phases of the ADC development, including target identification and validation. Leveraging an in-house, computationally constructed ADC target database, termed ADC Target Vault, we identified a set of novel ovarian cancer targets. We effectively demonstrate the efficacy of Surface Plasmon Resonance (SPR) technology and in vitro models as predictive tools, expediting the selection and validation of targets as ADC candidates for ovarian cancer therapy. Our analysis reveals three novel robust antibody/target pairs with strong binding and favourable antibody internalization rates in both wild-type and cisplatin-resistant ovarian cancer cell lines. This approach enhances ADC development and offers a comprehensive method for assessing target/antibody combinations and pre-payload conjugation biological activity. Additionally, the strategy establishes a robust platform for high-throughput screening of potential ovarian cancer ADC targets, an approach that is equally applicable to other cancer types.

2.
Stem Cell Res Ther ; 14(1): 265, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37740230

RESUMO

BACKGROUND: Down syndrome (DS) clinical multisystem condition is generally considered the result of a genetic imbalance generated by the extra copy of chromosome 21. Recent discoveries, however, demonstrate that the molecular mechanisms activated in DS compared to euploid individuals are more complex than previously thought. Here, we utilize mesenchymal stem cells from chorionic villi (CV) to uncover the role of comprehensive functional genomics-based understanding of DS complexity. METHODS: Next-generation sequencing coupled with bioinformatic analysis was performed on CV obtained from women carrying fetuses with DS (DS-CV) to reveal specific genome-wide transcriptional changes compared to their euploid counterparts. Functional assays were carried out to confirm the biological processes identified as enriched in DS-CV compared to CV (i.e., cell cycle, proliferation features, immunosuppression and ROS production). RESULTS: Genes located on chromosomes other than the canonical 21 (Ch. 2, 6 and 22) are responsible for the impairment of life-essential pathways, including cell cycle regulation, innate immune response and reaction to external stimuli were found to be differentially expressed in DS-CV. Experimental validation confirmed the key role of the biological pathways regulated by those genes in the etiology of such a multisystem condition. CONCLUSIONS: NGS dataset generated in this study highlights the compromised functionality in the proliferative rate and in the innate response of DS-associated clinical conditions and identifies DS-CV as suitable tools for the development of specifically tailored, personalized intervention modalities.


Assuntos
Síndrome de Down , Humanos , Feminino , Síndrome de Down/genética , Vilosidades Coriônicas , Transcriptoma , Células-Tronco , Cromossomos
3.
Front Cell Infect Microbiol ; 11: 752275, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660348

RESUMO

Objectives: To investigate whether women with overactive bladder (OAB) symptoms and no evidence of clinical infection by conventional clean-catch midstream urine cultures have alternative indicators of sub-clinical infection. Patients/Subjects Materials & Methods: The study was a prospective, blinded case-control study with 147 participants recruited, including 73 OAB patients and 74 controls. The OAB group comprised female patients of at least 18 years of age who presented with OAB symptoms for more than 3 months. Clean-catch midstream urine samples were examined for pyuria by microscopy; subjected to routine and enhanced microbiological cultures and examined for the presence of 10 different cytokines, chemokines, and prostaglandins by ELISA. Results: The mean age and BMI of participants in both groups were similar. No significant difference in the number of women with pyuria was observed between OAB and control groups (p = 0.651). Routine laboratory cultures were positive in three (4%) of women in the OAB group, whereas the enhanced cultures isolated bacteria in 17 (23.2%) of the OAB patients. In the control group, no positive cultures were observed using routine laboratory cultures, whereas enhanced culture isolated bacteria in 8 (10.8%) patients. No significant differences were observed in the concentrations of PGE2, PGF2α, MCP-1, sCD40L, MIP-1ß, IL12p70/p40, IL12/IL-23p40, IL-5, EGF and GRO-α between the OAB and control groups. Conclusions: Patients with OAB symptoms have significant bacterial growth on enhanced culture of the urine, which is often not detectable through routine culture, suggesting a subclinical infection. Enhanced culture techniques should therefore be used routinely for the effective diagnosis and management of OAB.


Assuntos
Bexiga Urinária Hiperativa , Infecções Urinárias , Estudos de Casos e Controles , Feminino , Humanos , Estudos Prospectivos , Bexiga Urinária Hiperativa/complicações , Infecções Urinárias/complicações
4.
Clin Transl Med ; 11(10): e551, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34709744

RESUMO

BACKGROUND: Ovarian cancer (OC) is typically diagnosed late, associated with high rates of metastasis and the onset of ascites during late stage disease. Understanding the tumor microenvironment and how it impacts the efficacy of current treatments, including immunotherapies, needs effective in vivo models that are fully characterized. In particular, understanding the role of immune cells within the tumor and ascitic fluid could provide important insights into why OC fails to respond to immunotherapies. In this work, we comprehensively described the immune cell infiltrates in tumor nodules and the ascitic fluid within an optimized preclinical model of advanced ovarian cancer. METHODS: Green Fluorescent Protein (GFP)-ID8 OC cells were injected intraperitoneally into C57BL/6 mice and the development of advanced stage OC monitored. Nine weeks after tumor injection, mice were sacrificed and tumor nodules analyzed to identify specific immune infiltrates by immunohistochemistry. Ascites, developed in tumor bearing mice over a 10-week period, was characterized by mass cytometry (CyTOF) to qualitatively and quantitatively assess the distribution of the immune cell subsets, and their relationship to ascites from ovarian cancer patients. RESULTS: Tumor nodules in the peritoneal cavity proved to be enriched in T cells, antigen presenting cells and macrophages, demonstrating an active immune environment and cell-mediated immunity. Assessment of the immune landscape in the ascites showed the predominance of CD8+ , CD4+ , B- , and memory T cells, among others, and the coexistance of different immune cell types within the same tumor microenvironment. CONCLUSIONS: We performed, for the first time, a multiparametric analysis of the ascitic fluid and specifically identify immune cell populations in the peritoneal cavity of mice with advanced OC. Data obtained highlights the impact of CytOF as a diagnostic tool for this malignancy, with the opportunity to concomitantly identify novel targets, and define personalized therapeutic options.


Assuntos
Neoplasias Ovarianas/imunologia , Microambiente Tumoral/imunologia , Animais , Ascite/imunologia , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL
6.
Front Cell Dev Biol ; 8: 553576, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042993

RESUMO

Exosomes are physiologically secreted nanoparticles recently established as natural delivery systems involved in cell-to-cell communication and content exchange. Due to their inherent targeting potential, exosomes are currently being harnessed for the development of anti-cancer therapeutics. Clinical trials evaluating their effectiveness are demonstrating safety and promising outcomes. However, challenging large-scale production, isolation, modification and purification of exosomes are current limitations for the use of naturally occurring exosomes in the clinic. Exosome mimetics hold the promise to improve the delivery of bioactive molecules with therapeutic efficacy, while achieving scalability and increasing bioavailability. In this study, we propose the development of Immune Derived Exosome Mimetics (IDEM) as a scalable approach to target and defeat ovarian cancer cells. IDEM were fabricated from monocytic cells by combining sequential filtration steps through filter membranes with different porosity and size exclusion chromatography columns. The physiochemical and molecular characteristics of IDEM were compared to those of natural exosomes (EXO). Nanoparticle Tracking Analysis confirmed a 2.48-fold increase in the IDEM production yields compared to EXO, with similar exosomal markers profiles (CD81, CD63) as demonstrated by flow cytometry and ELISA. To exploit the prospective of IDEM to deliver chemotherapeutics, doxorubicin (DOXO) was used as a model drug. IDEM showed higher encapsulation efficiency and drug release over time compared to EXO. The uptake of both formulations by SKOV-3 ovarian cancer cells was assessed by confocal microscopy and flow cytometry, showing an incremental drug uptake over time. The analysis of the cytotoxic and apoptotic effect of DOXO-loaded nanoparticles both in 2D and 3D culture systems proved IDEM as a more efficient system as compared to free DOXO, unraveling the advantage of IDEM in reducing side-effects while increasing cytotoxicity of targeted cells, by delivering smaller amount of the chemotherapeutic agent. The high yields of IDEM obtained compared to natural exosomes together with the time-effectiveness and reproducibility of their production method make this approach potentially exploitable for clinical applications. Most importantly, the appreciable cytotoxic effect observed on ovarian cancer in vitro systems sets the ground for the development of compelling nanotherapeutic candidates for the treatment of this malady and will be further evaluated.

7.
Stem Cells Dev ; 29(14): 882-894, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32364057

RESUMO

Articular cartilage contains a subpopulation of tissue-specific progenitors that are an ideal cell type for cell therapies and generating neocartilage for tissue engineering applications. However, it is unclear whether the standard chondrogenic medium using transforming growth factor beta (TGFß) isoforms is optimal to differentiate these cells. We therefore used pellet culture to screen progenitors from immature bovine articular cartilage with a number of chondrogenic factors and discovered that bone morphogenetic protein-9 (BMP9) precociously induces their differentiation. This difference was apparent with toluidine blue staining and confirmed by biochemical and transcriptional analyses with BMP9-treated progenitors exhibiting 11-fold and 5-fold greater aggrecan and collagen type II (COL2A1) gene expression than TGFß1-treated progenitors. Quantitative gene expression analysis over 14 days highlighted the rapid and phased nature of BMP9-induced chondrogenesis with sequential activation of aggrecan then collagen type II, and negligible collagen type X gene expression. The extracellular matrix of TGFß1-treated progenitors analyzed using atomic force microscopy was fibrillar and stiff whist BMP9-induced matrix of cells more compliant and correspondingly less fibrillar. Polarized light microscopy revealed an annular pattern of collagen fibril deposition typified by TGFß1-treated pellets, whereas BMP9-treated pellets displayed a birefringence pattern that was more anisotropic. Remarkably, differentiated immature chondrocytes incubated as high-density cultures in vitro with BMP9 generated a pronounced anisotropic organization of collagen fibrils indistinguishable from mature adult articular cartilage, with cells in deeper zones arranged in columnar manner. This contrasted with cells grown with TGFß1, where a concentric pattern of collagen fibrils was visualized within tissue pellets. In summary, BMP9 is a potent chondrogenic factor for articular cartilage progenitors and is also capable of inducing morphogenesis of adult-like cartilage, a highly desirable attribute for in vitro tissue-engineered cartilage.


Assuntos
Cartilagem Articular/citologia , Condrogênese , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco/citologia , Animais , Bovinos , Células Cultivadas , Colágeno/metabolismo , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Hidroxiprolina/metabolismo
8.
J Pharmacol Exp Ther ; 370(3): 636-646, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30737357

RESUMO

Ovarian cancer (OC) is the seventh most common cancer in women worldwide. Standard therapeutic treatments involve debulking surgery combined with platinum-based chemotherapies. Of the patients with advanced-stage cancer who initially respond to current treatments, 50%-75% relapse. Immunotherapy-based approaches aimed at boosting antitumor immunity have recently emerged as promising tools to challenge tumor progression. Treatments with inhibitors of immune checkpoint molecules have shown impressive results in other types of tumors. However, only 15% of checkpoint inhibitors evaluated have proven successful in OC due to the immunosuppressive environment of the tumor and the transport barriers. This limits the efficacy of the existing immunotherapies. Nanotechnology-based delivery systems hold the potential to overcome such limitations. Various nanoformulations including polymeric, liposomes, and lipid-polymer hybrid nanoparticles have already been proposed to improve the biodistribution and targeting capabilities of drugs against tumor-associated immune cells, including dendritic cells and macrophages. In this review, we examine the impact of immunotherapeutic approaches that are currently under consideration for the treatment of OC. In this review, we also provide a comprehensive analysis of the existing nanoparticle-based synthetic strategies and their limitations and advantages over standard treatments. Furthermore, we discuss how the strength of the combination of nanotechnology with immunotherapy may help to overcome the current therapeutic limitations associated with their individual application and unravel a new paradigm in the treatment of this malignancy.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Imunoterapia/tendências , Nanotecnologia/tendências , Neoplasias Ovarianas/tratamento farmacológico , Animais , Feminino , Humanos , Imunoterapia/métodos , Nanotecnologia/métodos
9.
Nanomedicine ; 14(7): 2235-2245, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30031940

RESUMO

During decidualization, human mesenchymal-like endometrial stromal cells undergo well characterized cellular and molecular transformations in preparation for accepting a developing embryo. Modulation of cellular biophysical properties during decidualization is likely to be important in receptivity and support of the embryo in the uterus. Here we assess the biophysical properties of human endometrial stromal cells including topography, roughness, adhesiveness and stiffness in cells undergoing in vitro decidualization. A significant reduction in cell stiffness and surface roughness was observed following decidualization. These morphodynamical changes have been shown to be associated with alterations in cellular behavior and homeostasis, suggesting that localized endometrial cell biophysical properties play a role in embryo implantation and pregnancy. This cell-cell communication process is thought to restrict trophoblast invasion beyond the endometrial stroma, be essential in the establishment of pregnancy, and demonstrate the altered endometrial dynamics affecting cell-cell contact and migration regimes at this crucial interface in human reproduction.


Assuntos
Decídua/citologia , Implantação do Embrião , Endométrio/citologia , Células Epiteliais/citologia , Células Estromais/citologia , Adolescente , Adulto , Células Cultivadas , Decídua/ultraestrutura , Endométrio/ultraestrutura , Células Epiteliais/ultraestrutura , Feminino , Humanos , Microscopia Confocal , Gravidez , Células Estromais/ultraestrutura , Adulto Jovem
10.
FEBS Lett ; 579(7): 1702-6, 2005 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-15757664

RESUMO

Visualisation of nano-scale biomolecules aids understanding and development in molecular biology and nanotechnology. Detailed structure of nucleosomes adsorbed to mica has been captured in the absence of chemical-anchoring techniques, demonstrating the usefulness of non-contact atomic force microscopy (NC-AFM) for ultra-high resolution biomolecular imaging. NC-AFM offers significant advantages in terms of resolution, speed and ease of sample preparation when compared to techniques such as cryo-electron microscopy and X-ray crystallography. In the absence of chemical modification, detailed structure of DNA deposited on a gold substrate was observed for the first time using NC-AFM, opening up possibilities for investigating the electrical properties of unmodified DNA.


Assuntos
DNA/ultraestrutura , Microscopia de Força Atômica , Nucleossomos/ultraestrutura , Silicatos de Alumínio/química , DNA/química , Nanotecnologia , Conformação de Ácido Nucleico , Nucleossomos/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...