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1.
Curr Pharm Biotechnol ; 21(13): 1377-1385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32410562

RESUMO

OBJECTIVE: Heart dysfunctions are the major complications of trastuzumab in patients with Human Epidermal growth factor Receptor-2 (HER2)-positive breast cancers. METHODS: In this study, the cytotoxicity of trastuzumab on H9c2 cardiomyoblasts was demonstrated, and the proteome changes of cells were investigated by a tandem mass tagging quantitative approach. The Differentially Abundant Proteins (DAPs) were identified and functionally enriched. RESULTS: We determined that carvedilol, a non-selective beta-blocker, could effectively inhibit trastuzumab toxicity when administrated in a proper dose and at the same time. The proteomics analysis of carvedilol co-treated cardiomyoblasts showed complete or partial reversion in expressional levels of trastuzumab-induced DAPs. CONCLUSION: Downregulation of proteins involved in the translation biological process is one of the most important changes induced by trastuzumab and reversed by carvedilol. These findings provide novel insights to develop new strategies for the cardiotoxicity of trastuzumab.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Antineoplásicos Imunológicos/toxicidade , Carvedilol/farmacologia , Mioblastos Cardíacos/efeitos dos fármacos , Proteoma/metabolismo , Trastuzumab/toxicidade , Antagonistas Adrenérgicos beta/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Cardiomiopatias/prevenção & controle , Carvedilol/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Regulação para Baixo , Feminino , Humanos , Mioblastos Cardíacos/metabolismo , Mioblastos Cardíacos/patologia , Proteômica , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapêutico
2.
J Biomed Mater Res A ; 108(8): 1596-1606, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32180319

RESUMO

The interaction between osteogenic and angiogenic cells through a coculturing system in biocompatible materials has been considered for successfully engineering vascularized bone tissue equivalents. In this study, we developed a hydrogel-blended scaffold consisted of gelatin methacryloyl (GelMA) and alginate enriched with hydroxyapatite nanoparticles (HAP) to model an in vitro prevascularized bone construct. The hydrogel-based scaffold revealed a higher mechanical stiffness than those of pure (GelMA), alginate, and (GelMA+ HAP) hydrogels. In the present study, we generated a green fluorescent protein (GFP) knock-in umbilical vein endothelial cells (HUVECs) cell line using the CRISPR/Cas9 technology. The GFP was inserted into the human-like ROSA locus of HUVECs genome. HUVECs expressing GFP were cocultured with OB-like cells (MG-63) within three-dimensionally (3D) fabricated hydrogel to investigate the response of cocultured osteoblasts and endothelial cells in a 3D structure. Cell viability under the 3D cocultured gel was higher than the 3D monocultured. Compared to the 3D monocultured condition, the cells were aligned and developed into the vessel-like structures. During 14 days of culture periods, the cells displayed actin protrusions by the formation of spike-like filopodia in the 3D cocultured model. Angiogenic and osteogenic-related genes such as CD31, vWF, and osteocalcin showed higher expression in the cocultured versus the monocultured. These results have collectively indicated that the 3D cocultured hydrogel facilitates interaction among cells, thereby having a greater effect on angiogenic and osteogenic properties in the absence of induction media.


Assuntos
Comunicação Celular , Proteínas de Fluorescência Verde/genética , Células Endoteliais da Veia Umbilical Humana/citologia , Osteoblastos/citologia , Alginatos/química , Sistemas CRISPR-Cas , Linhagem Celular , Técnicas de Cocultura/métodos , Técnicas de Introdução de Genes/métodos , Proteínas de Fluorescência Verde/análise , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Osteoblastos/metabolismo , Alicerces Teciduais/química
3.
Transl Res ; 216: 57-76, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31526771

RESUMO

Vascularization has a pivotal role in engineering successful tissue constructs. However, it remains a major hurdle of bone tissue engineering, especially in clinical applications for the treatment of large bone defects. Development of vascularized and clinically-relevant engineered bone substitutes with sufficient blood supply capable of maintaining implant viability and supporting subsequent host tissue integration remains a major challenge. Since only cells that are 100-200 µm from blood vessels can receive oxygen through diffusion, engineered constructs that are thicker than 400 µm face a challenging oxygenation problem. Following implantation in vivo, spontaneous ingrowth of capillaries in thick engineered constructs is too slow. Thus, it is critical to provide optimal conditions to support vascularization in engineered bone constructs. To achieve this, an in-depth understanding of the mechanisms of angiogenesis and bone development is required. In addition, it is also important to mimic the physiological milieu of native bone to fabricate more successful vascularized bone constructs. Numerous applications of engineered vascularization with cell-and/or microfabrication-based approaches seek to meet these aims. Three-dimensional (3D) printing promises to create patient-specific bone constructs in the future. In this review, we discuss the major components of fabricating vascularized 3D bioprinted bone constructs, analyze their related challenges, and highlight promising future trends.


Assuntos
Bioimpressão , Osso e Ossos/irrigação sanguínea , Neovascularização Fisiológica , Engenharia Tecidual/métodos , Animais , Técnicas de Cocultura , Humanos , Alicerces Teciduais
4.
Curr Stem Cell Res Ther ; 14(3): 268-277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30588888

RESUMO

Development of multicellular organisms is a very complex and organized process during which cells respond to various factors and features in extracellular environments. It has been demonstrated that during embryonic evolvement, under certain physiological or experimental conditions, unspecialized cells or stem cells can be induced to become tissue or organ-specific cells with special functions. Considering the importance of physical cues in stem cell fate, the present study reviews the role of physical factors in stem cells differentiation and discusses the molecular mechanisms associated with these factors.


Assuntos
Citoesqueleto de Actina/metabolismo , Células-Tronco Embrionárias/metabolismo , Adesões Focais/metabolismo , Integrinas/metabolismo , Mecanotransdução Celular , Proteínas rho de Ligação ao GTP/metabolismo , Citoesqueleto de Actina/ultraestrutura , Animais , Fenômenos Biomecânicos , Diferenciação Celular , Forma Celular/fisiologia , Elasticidade , Embrião de Mamíferos , Células-Tronco Embrionárias/citologia , Adesões Focais/ultraestrutura , Regulação da Expressão Gênica , Dureza , Humanos , Integrinas/genética , Pressão Osmótica , Tensão Superficial , Proteínas rho de Ligação ao GTP/genética
5.
Sci Rep ; 8(1): 12557, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135553

RESUMO

The surface of nanoparticles (NPs) get coated by a wide range of biomolecules, upon exposure to biological fluids. It is now being increasingly accepted that NPs with particular physiochemical properties have a capacity to induce conformational changes to proteins and therefore influence their biological fates, we hypothesized that the gold NP's metal surface may also be involved in the observed Fg unfolding and inflammatory response. To mechanistically test this hypothesis, we probed the interaction of Fg with gold surfaces using molecular dynamic simulation (MD) and revealed that the gold surface has a capacity to induce Fg conformational changes in favor of inflammation response. As the integrity of coatings at the surface of ultra-small gold NPs are not thorough, we also hypothesized that the ultra-small gold NPs have a capacity to induce unfolding of Fg regardless of the composition and surface charge of their coatings. Using different surface coatings at the surface of ultra-small gold NPs, we validated this hypothesis. Our findings suggest that gold NPs may cause unforeseen inflammatory effects, as their surface coatings may be degraded by physiological activity.


Assuntos
Fibrinogênio/química , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas , Desdobramento de Proteína/efeitos dos fármacos , Cetrimônio/metabolismo , Fibrinogênio/metabolismo , Humanos , Inflamação/sangue , Inflamação/induzido quimicamente , Inflamação/metabolismo , Simulação de Dinâmica Molecular , Conformação Proteica , Transporte Proteico , Propriedades de Superfície
6.
J Biomed Mater Res A ; 105(7): 1984-1993, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28256789

RESUMO

In this study, gold nanoparticles/Polyvinylidenefluoride (PVDF) composite electrospun mat with enhanced piezoelectricity were fabricated and characterized. Gold colloidal nanoparticles (Au NPs) were prepared via laser ablation of metallic targets in liquid media. The active Q-switched Nd:YAG laser was used as an irradiation source. Then, PVDF was dissolved in Au NPs colloidal solution at 30% wt for the synthesis of Au NPs/PVDF composite nanofibers by electrospinning. The optical absorbance spectra of Au NPS and the polymeric solutions were obtained by the UV-Visible spectroscopy. Moreover, the morphology of Au NPS, nanostructures of fibers and diameter size distribution of nanofibers were analyzed by Scanning Electron Microscopy, Field Emission Scanning Electron Microscopy, and Transmitted Electron Microscopy methods. The crystallinity and piezoelectricity of PVDF and Au NPs/PVDF composite nanofibers mats were measured by X-Ray Diffraction and Fourier Transform Infrared methods. Subsequently, in vitro cytocompatibility was evaluated by MTT assay and the attachment and morphology of PC-12 cells cultured on scaffolds were studied. It was found that laser ablated Au NPs can be used in electrospun nanofibers of PVDF with adequate structural properties and increase piezoelectricity of nanofibers which might be suitable for applying as nerve tissue engineering scaffolds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1984-1993, 2017.


Assuntos
Técnicas Eletroquímicas , Ouro/química , Nanocompostos/química , Tecido Nervoso , Polivinil/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Células PC12 , Ratos
7.
Biotechnol Appl Biochem ; 64(3): 423-432, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27037851

RESUMO

A novel biotinylated chitosan-graft-polyethyleneimine (Bio-Chi-g-PEI) copolymer was synthesized and evaluated as a nonviral gene delivery carrier for improvement of the transfection efficiency, endosomal escape, and targeted gene delivery of a plasmid encoding green fluorescent protein N1 (pEGFP-N1) into two different biotin-overexpressing cell lines including HeLa and OVCAR-3 cells. The structure of the obtained copolymers was confirmed by 1 H nuclear magnetic resonance (1 H NMR) and Fourier transform infrared spectroscopy. Physicochemical properties of the Bio-Chi-g-PEI/plasmid DNA (pDNA) complexes such as complex stability, size, zeta potential, and their morphology were investigated at various weight ratios of copolymer to pDNA. Bio-Chi-g-PEI copolymers could effectively condense pDNA into small particles with average diameters less than 164 nm and the zeta potential of +34.8 mV at the N/P ratio of 40/1. As revealed by flow cytometry, Bio-Chi-g-PEI/pDNA complexes had lower cytotoxicity than that of PEI 25 kDa/pDNA complexes in both cell lines. In vitro experiments revealed that the Bio-Chi-gPEI/pDNA complexes not only had much lower cytotoxicity, but also displayed higher transfection efficiency than that of PEI 25kDa/pDNA complexes. High percentage of cancer cells was successfully transfected by Bio-Chi-g-PEI/pDNA and properly expressed GFP protein. This study indicates that this copolymer complex can be a promising gene delivery carrier.


Assuntos
Biotina/química , Quitosana/química , Técnicas de Transferência de Genes , Neoplasias/metabolismo , Plasmídeos , Proteínas de Fluorescência Verde/biossíntese , Células HeLa , Humanos , Neoplasias/patologia , Neoplasias/terapia , Plasmídeos/química , Plasmídeos/farmacologia
8.
Int J Pharm ; 456(2): 408-16, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24012865

RESUMO

The major impediments to develop an efficient non-viral siRNA-mediated gene silencing method, as a therapeutic approach, are the low cellular uptake and intracellular delivery and release of non-viral vectors. To overcome these problems, designing a proper vector with high transfection efficiency is obviously under scrutiny of various studies. The present study, evaluate a novel biotinylated chitosan-graft-polyethyleneimine (Bio-Chi-g-PEI) copolymer as an appropriate non-viral vector for targeted delivery of siRNA to cancer cells. The composition of the synthesized Bio-Chi-g-PEI copolymer was thoroughly characterized using (1)H NMR and FTIR spectroscopy, besides the hydroxyazobenzene-2-carboxylic acid (HABA) assay. In vitro cytotoxicity assay of the Bio-Chi-g-PEI copolymers was performed by MTT assay. Cytotoxicity evaluations indicated that the new copolymer was markedly less toxic than PEI 25KD. Physicochemical properties of the Bio-Chi-g-PEI/siRNA complexes such as complex stability, size, zeta potential, and their morphology at various weight ratios, investigated by appropriate methods, revealed the suitability of the complexes for the transfection. The efficient cellular internalization of the complexes for HeLa and OVCAR-3 cells in culture media was confirmed by intracellular tracking of the prepared complexes using confocal laser scanning microscopy and Cy3-labeled anti-epidermal growth factor receptor siRNA. Finally, evaluation of the transfection efficiency and gene silencing by flow cytometry and real-time polymerase chain reaction highlighted the significantly higher efficiency of transfection and silencing for biotinylated copolymer compared with the PEI 25KD and non-biotinylated copolymer.


Assuntos
Biotinilação/métodos , Quitosana/análogos & derivados , Receptores ErbB , Técnicas de Transferência de Genes , Vetores Genéticos/administração & dosagem , Polietilenoimina/análogos & derivados , RNA Interferente Pequeno/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Quitosana/administração & dosagem , Quitosana/química , Relação Dose-Resposta a Droga , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Marcação de Genes/métodos , Vetores Genéticos/química , Células HeLa , Humanos , Polietilenoimina/administração & dosagem , Polietilenoimina/química , Polímeros/administração & dosagem , Polímeros/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética
9.
ACS Nano ; 7(10): 8379-84, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24059979

RESUMO

Smart nanoenvironments were obtained by cell-imprinted substrates based on mature and dedifferentiated chondrocytes as templates. Rabbit adipose derived mesenchymal stem cells (ADSCs) seeded on these cell-imprinted substrates were driven to adopt the specific shape (as determined in terms of cell morphology) and molecular characteristics (as determined in terms of gene expression) of the cell types which had been used as template for the cell-imprinting. This method might pave the way for a reliable, efficient, and cheap way of controlling stem cell differentiation. Data also suggest that besides residual cellular fragments, which are presented on the template surface, the imprinted topography of the templates plays a role in the differentiation of the stem cells.


Assuntos
Células-Tronco Mesenquimais/citologia , Tecido Adiposo/citologia , Animais , Diferenciação Celular , Linhagem da Célula , Perfilação da Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Coelhos
10.
ACS Nano ; 7(8): 6555-62, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23808533

RESUMO

Upon incorporation of nanoparticles (NPs) into the body, they are exposed to biological fluids, and their interaction with the dissolved biomolecules leads to the formation of the so-called protein corona on the surface of the NPs. The composition of the corona plays a crucial role in the biological fate of the NPs. While the effects of various physicochemical parameters on the composition of the corona have been explored in depth, the role of temperature upon its formation has received much less attention. In this work, we have probed the effect of temperature on the protein composition on the surface of a set of NPs with various surface chemistries and electric charges. Our results indicate that the degree of protein coverage and the composition of the adsorbed proteins on the NPs' surface depend on the temperature at which the protein corona is formed. Also, the uptake of NPs is affected by the temperature. Temperature is, thus, an important parameter that needs to be carefully controlled in quantitative studies of bionano interactions.


Assuntos
Nanopartículas/química , Adsorção , Biotecnologia , Coloides/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Cinética , Magnetismo , Espectrometria de Massas , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Polímeros/química , Ligação Proteica , Proteínas/química , Albumina Sérica/química , Propriedades de Superfície , Temperatura
11.
Nanoscale ; 5(8): 3240-4, 2013 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-23508197

RESUMO

It is known that what the cell actually "sees" at the nanoscale is an outer shell formed of 'protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature.


Assuntos
Células/efeitos dos fármacos , Células/metabolismo , Nanopartículas de Magnetita/toxicidade , Proteínas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Materiais Revestidos Biocompatíveis/farmacocinética , Compostos Férricos/química , Compostos Férricos/farmacocinética , Compostos Férricos/toxicidade , Humanos , Nanopartículas de Magnetita/química , Estresse Oxidativo/efeitos dos fármacos , Ligação Proteica , Proteínas/química , Proteínas/farmacocinética , Espécies Reativas de Oxigênio/metabolismo , Albumina Sérica/metabolismo , Especificidade por Substrato , Propriedades de Superfície , Temperatura
12.
ACS Chem Neurosci ; 4(3): 375-8, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23509973

RESUMO

Amyloid beta fibrillation can lead to major disorder of neurons processes and is associated with several neuronal diseases (e.g., Alzheimer's disease). We report here an importance of slight temperature changes, in the physiological range (35-42 °C), on the amyloid fibrillation process in the presence and absence of hydrophilic (silica) and hydrophobic (polystyrene) nanoparticles (NPs). The results highlight the fact that slight increases in temperature can induce inhibitory and acceleratory effects of hydrophobic and hydrophilic NPs on the fibrillation process, respectively. Using further in vivo considerations, the outcomes of this study can be used for considerable modifications on the current diagnosis and treatment approaches in amyloid-involved diseases.


Assuntos
Peptídeos beta-Amiloides/fisiologia , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Nanopartículas/toxicidade , Fenômenos Fisiológicos/fisiologia , Temperatura , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/biossíntese , Poliestirenos/química , Poliestirenos/toxicidade , Dióxido de Silício/química , Dióxido de Silício/toxicidade
13.
Cancer Lett ; 334(2): 237-44, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22902507

RESUMO

Despite the preclinical success of adoptive therapy with T cells bearing chimeric nanoconstructed antigen receptors (CARs), certain limitations of this therapeutic approach such as the immunogenicity of the antigen binding domain, the emergence of tumor cell escape variants and the blocking capacity of soluble antigen still remain. Here, we address these issues using a novel CAR binding moiety based on the oligoclonal camelid single domain antibodies. A unique set of 13 single domain antibodies were selected from an immunized camel phage library based on their target specificity and binding affinity. A combination of these single domain antibodies was used to generate four tumor associated glycoprotein (TAG-72)-specific CARs harboring an identical antigen binding site, but with different signaling and spacer domains. Although all four CARs were functionally active against the TAG-72 expressing tumor cells, the combination of CD3ζ, OX40, CD28 as well as the CH3-CH2-hinge-hinge domains most efficiently triggered T cell activation. Importantly, CAR mediated functions were not blocked by the soluble TAG-72 antigen at a supraphysiological concentration. Our approach may have the potential to reverse multiple tumor immune evasion mechanisms, avoid CAR immunogenicity, and overcome problems in cancer gene therapy with engineered nanoconstructs.


Assuntos
Antígenos de Neoplasias/imunologia , Engenharia Genética/métodos , Glicoproteínas/imunologia , Imunoterapia Adotiva/métodos , Receptores de Antígenos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Domínio Único/imunologia , Linfócitos T/imunologia , Animais , Especificidade de Anticorpos , Antígenos de Neoplasias/genética , Camelídeos Americanos , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/terapia , Neoplasias do Colo/imunologia , Neoplasias do Colo/terapia , Glicoproteínas/genética , Células HT29 , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Leucemia de Células T/imunologia , Leucemia de Células T/terapia , Ativação Linfocitária , Biblioteca de Peptídeos , Receptores de Antígenos/genética , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais , Anticorpos de Domínio Único/genética , Linfócitos T/fisiologia , Transfecção
14.
Nanoscale ; 4(17): 5461-8, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22842341

RESUMO

Engineered nanoparticles are increasingly being considered for use as biosensors, imaging agents and drug delivery vehicles. Their versatility in design and applications make them an attractive proposition for new biological and biomedical approaches. Despite the remarkable speed of development in nanoscience, relatively little is known about the interaction of nanoscale objects with living systems. In a biological fluid, proteins associate with nanoparticles, and the amount and the presentation of the proteins on their surface could lead to a different in vivo response than an uncoated particle. Here, in addition to protein adsorption, we are going to introduce concept of cell "vision", which would be recognized as another crucial factor that should be considered for the safe design of any type of nanoparticles that will be used in specific biomedical applications. The impact of exactly the same nanoparticles on various cells is significantly different and could not be assumed for other cells; the possible mechanisms that justify this cellular response relate to the numerous detoxification strategies that any particular cell can utilize in response to nanoparticles. The uptake and defence mechanism could be considerably different according to the cell type. Thus, what the cell "sees", when it is faced with nanoparticles, is most likely dependent on the cell type.


Assuntos
Nanopartículas/química , Proteínas/química , Adsorção , Técnicas Biossensoriais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Células Jurkat , Lisossomos/química , Lisossomos/metabolismo , Microscopia de Fluorescência , Nanopartículas/toxicidade , Proteínas/metabolismo , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo
15.
Exp Cell Res ; 318(10): 1112-24, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22440788

RESUMO

Modern anti-HER2 antibody therapy tends to exploit a panel of different antibodies against different epitopes on the antigen. For this aim, nanobodies are very striking targeting agents and can be easily produced against any cell-specific membrane antigen. The oligoclonal nanobodies can be used to block more than one functional epitope on a target antigen and inhibit the generation of escape variants associated with cancer therapy. In this study, 12 nanobody clones selected from an immune camel library were examined for their ability to differ between tumor markers. These oligoclonal nanobodies targeted breast cancer cells better than each individual nanobody. In epitope mapping, several nanobodies overlapped in the epitope recognized by trastuzumab and some of the non-overlapping nanobodies could affect the binding of trastuzumab to HER2. This study demonstrates that the oligoclonal nanobodies are potential therapeutic tools that can be used instead of, or in combination with trastuzumab to assess tumor viability during treatment.


Assuntos
Epitopos/imunologia , Fragmentos de Imunoglobulinas/biossíntese , Cadeias Pesadas de Imunoglobulinas/biossíntese , Receptor ErbB-2/imunologia , Animais , Anticorpos Monoclonais Humanizados/química , Afinidade de Anticorpos , Especificidade de Anticorpos , Antineoplásicos/química , Ligação Competitiva , Camelus , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Citometria de Fluxo , Humanos , Fragmentos de Imunoglobulinas/química , Fragmentos de Imunoglobulinas/isolamento & purificação , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/isolamento & purificação , Camundongos , Biblioteca de Peptídeos , Ligação Proteica , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Trastuzumab
16.
Chem Commun (Camb) ; 48(33): 3957-9, 2012 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-22422277

RESUMO

Because of their multifunctionality and unique magnetic properties, superparamagnetic iron oxide nanoparticles (SPIONs) have been recognized as very promising materials for various biomedical applications. The main difficulty with the use of SPIONs as multimodal bioimaging agents is their lack of fluorescence. Since cells can act as extremely efficient filters for the elution of surface-bound fluorescent tags with nanoparticles, the surface loaded fluorescence dyes significantly decay after a short period of time. Here, for the first time, we introduce novel, engineered multimodal SPIONs with a permanent fluorescence capability, the study of which can lead to a deeper understanding of biological processes at the biomolecular level, greatly influencing molecular diagnostics, imaging and therapeutic applications.


Assuntos
Compostos Férricos/química , Corantes Fluorescentes/química , Imãs/química , Nanopartículas/química , Ouro/química , Modelos Moleculares , Conformação Molecular , Polímeros/química
17.
Cell Biol Int ; 36(4): 403-8, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22214203

RESUMO

Arsenical compounds exhibit a differential toxicity to cancer cells. Microtubules are a primary target of a number of anticancer drugs, such as arsenical compounds. The interaction of 1-NAA (1-naphthylarsonic acid) has been investigated on microtubule polymerization under in vitro and cellular conditions. Microtubules were extracted from sheep brain. Transmission electron microscopy was used to show microtubule structure in the presence of 1-NAA. Computational docking method was applied for the discovery of ligand-binding sites on the microtubular proteins. Proliferation of HeLa cells and HF2 (human foreskin fibroblasts) was measured by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay method following their incubation with 1-NAA. Fluorescence microscopic labelling was done with the help of α-tubulin monoclonal antibody and Tunel kit was used to investigate the apoptotic effects of 1-NAA on the HeLa cells. 1-NAA inhibits the tubulin polymerization by the formation of abnormal polymers having high affinity to the inner cell wall.


Assuntos
Arsenicais/farmacologia , Microtúbulos/efeitos dos fármacos , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Animais , Apoptose/efeitos dos fármacos , Arsenicais/química , Arsenicais/metabolismo , Sítios de Ligação , Encéfalo/metabolismo , Proliferação de Células/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células HeLa , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia Eletrônica de Transmissão , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Modelos Moleculares , Polimerização , Ligação Proteica , Ovinos , Sais de Tetrazólio , Tiazóis , Extratos de Tecidos/química , Tubulina (Proteína)/química , Tubulina (Proteína)/ultraestrutura , Moduladores de Tubulina/química , Moduladores de Tubulina/metabolismo
18.
Chem Commun (Camb) ; 47(37): 10404-6, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21837332

RESUMO

The creation of novel engineered multimodal nanoparticles (NPs) is a key focus in bionanotechnology and can lead to deep understanding of biological processes at the molecular level. Here, we present a multi-component system made of gold-coupled core-shell SPIONs, as a new nanoprobe with signal enhancement in surface Raman spectroscopy, due to its jagged-shaped gold shell coating.


Assuntos
Compostos Férricos/química , Ouro/química , Imãs/química , Nanopartículas/química , Análise Espectral Raman/métodos
19.
ACS Nano ; 5(9): 7263-76, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21838310

RESUMO

In the last few decades, nanoparticles (NPs) have been recognized as promising candidates for starting a new revolution in science and technology due to their unusual properties, attracting the attention of physicists, chemists, biologists, and engineers. The aim of this study is to evaluate the toxicities (at both cellular and molecular levels) of three forms of superparamagnetic iron oxide nanoparticles (SPIONs) of various surface chemistries (COOH, plain, and NH(2)) through the comparison with gene expression patterns of three cell types (i.e., human heart, brain, and kidney). For this purpose, both an MTT assay and a DNA microarray analysis were applied in three human cell lines--HCM (heart), BE-2-C (brain), and 293T (kidney)--under the exposure to SPIONs-COOH, SPIONs-NH(2), and bare SPIONs. The specific gene alteration and hierarchical clustering revealed that SPIONs-COOH altered genes associated with cell proliferative responses due to their reactive oxygen species (ROS) properties. It was also found that the cell type can have quite a significant role in the definition of suitable pathways for detoxification of NPs, which has deep implications for the safe and high yield design of NPs for biomedical applications and will require serious consideration in the future.


Assuntos
Compostos Férricos/toxicidade , Nanopartículas Metálicas , Nanopartículas , Microscopia Eletrônica de Transmissão , Análise de Sequência com Séries de Oligonucleotídeos
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