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1.
Sci Rep ; 13(1): 4673, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949092

RESUMO

The current COVID19 pandemic is caused by a positive-sense single-stranded RNA virus, which presents high mutational rates. The development of effective therapeutics and mitigation strategies using vaccination or therapeutic antibodies faces serious challenges because of the regular emergence of immune escape variants of the virus. An efficient approach would involve the use of an agent to non-specifically limit or block viruses contacting the mucosae and therefore entering the body. Here, we investigated the ability of a micronized purified clinoptilolite-tuff to bind and neutralize different viruses from the Coronaviridae family. Using plaque assay, RT-qPCR and immunostaining, the adsorption and inactivation of the seasonal human coronavirus HCoV-229E and of 2 SARS-CoV-2 variants were demonstrated. The resulting data suggest that purified clinoptilolite-tuff could be used as an ingredient in new medical devices and/or pharmaceuticals to prevent or mitigate SARS-CoV-2 dissemination.


Assuntos
COVID-19 , Coronaviridae , Humanos , SARS-CoV-2
2.
Sci Rep ; 13(1): 11783, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37479788

RESUMO

In this work, we present DrugSolver CavitomiX, a novel computational pipeline for drug repurposing and identifying ligands and inhibitors of target enzymes. The pipeline is based on cavity point clouds representing physico-chemical properties of the cavity induced solely by the protein. To test the pipeline's ability to identify inhibitors, we chose enzymes essential for SARS-CoV-2 replication as a test system. The active-site cavities of the viral enzymes main protease (Mpro) and papain-like protease (Plpro), as well as of the human transmembrane serine protease 2 (TMPRSS2), were selected as target cavities. Using active-site point-cloud comparisons, it was possible to identify two compounds-flufenamic acid and fusidic acid-which show strong inhibition of viral replication. The complexes from which fusidic acid and flufenamic acid were derived would not have been identified using classical sequence- and structure-based methods as they show very little structural (TM-score: 0.1 and 0.09, respectively) and very low sequence (~ 5%) identity to Mpro and TMPRSS2, respectively. Furthermore, a cavity-based off-target screening was performed using acetylcholinesterase (AChE) as an example. Using cavity comparisons, the human carboxylesterase was successfully identified, which is a described off-target for AChE inhibitors.


Assuntos
COVID-19 , Ácido Fusídico , Humanos , Ácido Fusídico/farmacologia , Acetilcolinesterase , Ácido Flufenâmico/farmacologia , SARS-CoV-2 , Peptídeo Hidrolases , Papaína
3.
Mol Imaging Biol ; 22(1): 47-65, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049831

RESUMO

Here, we report on the outcome of the 2nd International Danube Symposium on advanced biomarker development that was held in Vienna, Austria, in early 2018. During the meeting, cross-speciality participants assessed critical aspects of non-invasive, quantitative biomarker development in view of the need to expand our understanding of disease mechanisms and the definition of appropriate strategies both for molecular diagnostics and personalised therapies. More specifically, panelists addressed the main topics, including the current status of disease characterisation by means of non-invasive imaging, histopathology and liquid biopsies as well as strategies of gaining new understanding of disease formation, modulation and plasticity to large-scale molecular imaging as well as integrative multi-platform approaches. Highlights of the 2018 meeting included dedicated sessions on non-invasive disease characterisation, development of disease and therapeutic tailored biomarkers, standardisation and quality measures in biospecimens, new therapeutic approaches and socio-economic challenges of biomarker developments. The scientific programme was accompanied by a roundtable discussion on identification and implementation of sustainable strategies to address the educational needs in the rapidly evolving field of molecular diagnostics. The central theme that emanated from the 2nd Donau Symposium was the importance of the conceptualisation and implementation of a convergent approach towards a disease characterisation beyond lesion-counting "lumpology" for a cost-effective and patient-centric diagnosis, therapy planning, guidance and monitoring. This involves a judicious choice of diagnostic means, the adoption of clinical decision support systems and, above all, a new way of communication involving all stakeholders across modalities and specialities. Moreover, complex diseases require a comprehensive diagnosis by converging parameters from different disciplines, which will finally yield to a precise therapeutic guidance and outcome prediction. While it is attractive to focus on technical advances alone, it is important to develop a patient-centric approach, thus asking "What can we do with our expertise to help patients?"


Assuntos
Biomarcadores/metabolismo , Congressos como Assunto/organização & administração , Imagem Molecular/métodos , Neoplasias/patologia , Relatório de Pesquisa , Áustria , Biomarcadores/análise , Humanos , Agências Internacionais , Imagem Molecular/instrumentação , Imagem Molecular/tendências , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Neoplasias/terapia
4.
Biochim Biophys Acta ; 1782(12): 764-74, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18805482

RESUMO

Inclusion bodies are characteristic morphological features of various neuronal, muscular and other human disorders. They share common molecular constituents such as p62, chaperones and proteasome subunits. The proteins within aggregates are misfolded with increased beta-sheet structure, they are heavily phosphorylated, ubiquitinylated and partially degraded. Furthermore, involvement of proteasomal system represents a common feature of virtually all inclusions. Multiple aggregates contain intermediate filament proteins as their major constituents. Among them, Mallory-Denk bodies (MDBs) are the best studied. MDBs represent hepatic inclusions observed in diverse chronic liver diseases such as alcoholic and non-alcoholic steatohepatitis, chronic cholestasis, metabolic disorders and hepatocellular neoplasms. MDBs are induced in mice fed griseofulvin or 3,5-diethoxycarbonyl-1,4-dihydrocollidine and resolve after discontinuation of toxin administration. The availability of a drug-induced model makes MDBs a unique tool for studying inclusion formation. Our review summarizes the recent advances gained from this model and shows how they relate to observations in other aggregates. The MDB formation-underlying mechanisms include protein misfolding, chaperone alterations, disproportional protein expression with keratin 8>keratin 18 levels and subsequent keratin 8 crosslinking via transglutaminase. p62 presence is crucial for MDB formation. Proteasome inhibitors precipitate MDB formation, whereas stimulation of autophagy with rapamycin attenuates their formation.


Assuntos
Corpos de Inclusão/metabolismo , Queratinas/metabolismo , Hepatopatias/metabolismo , Animais , Humanos , Corpos de Inclusão/patologia , Hepatopatias/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo
5.
J Cell Biol ; 140(6): 1441-51, 1998 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-9508776

RESUMO

Here, we report on the analysis of keratin 18 null mice. Unlike the ablation of K8, which together with K18 is expressed in embryonic and simple adult epithelia, K18 null mice are viable, fertile, and show a normal lifespan. In young K18 null mice, hepatocytes were completely devoid of keratin filaments. Nevertheless, typical desmosomes were formed and maintained. Old K18 null mice, however, developed a distinctive liver pathology with abnormal hepatocytes containing K8-positive aggregates. These stained positively for ubiquitin and MM120-1 and were identified as Mallory bodies, one hallmark of human alcoholic hepatitis. This is the first demonstration that the ablation of one keratin leads to the accumulation of its single partner. Another striking finding was the absence or drastic down regulation of K7 in several tissues despite its ongoing transcription. Moreover, K18 null mice revealed new insights in the filament-forming capacity of the tail-less K19 in vivo. Due to the unexpected secondary loss of K7, only K8/19 are expressed in the uterine epithelium of K18 null mice. Immunoelectron microscopy of this tissue demonstrated the presence of typical K8/19 IF, thus highlighting in vivo that K19 is a fully competent partner for K8.


Assuntos
Células Epiteliais/química , Filamentos Intermediários/metabolismo , Queratinas/genética , Queratinas/metabolismo , Fatores Etários , Animais , Anticorpos Monoclonais , Desmossomos/fisiologia , Desmossomos/ultraestrutura , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Fertilidade , Expressão Gênica , Heterozigoto , Homozigoto , Filamentos Intermediários/química , Filamentos Intermediários/imunologia , Queratina-7 , Queratinas/imunologia , Expectativa de Vida , Fígado/química , Fígado/patologia , Camundongos , Camundongos Knockout , Microscopia Imunoeletrônica , Mutagênese/genética , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Células-Tronco/química , Células-Tronco/citologia , Células-Tronco/fisiologia
6.
J Cell Biol ; 145(5): 1049-61, 1999 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-10352021

RESUMO

Mice lacking the AP-1 transcription factor c-Jun die around embryonic day E13.0 but little is known about the cell types affected as well as the cause of embryonic lethality. Here we show that a fraction of mutant E13.0 fetal livers exhibits extensive apoptosis of both hematopoietic cells and hepatoblasts, whereas the expression of 15 mRNAs, including those of albumin, keratin 18, hepatocyte nuclear factor 1, beta-globin, and erythropoietin, some of which are putative AP-1 target genes, is not affected. Apoptosis of hematopoietic cells in mutant livers is most likely not due to a cell-autonomous defect, since c-jun-/- fetal liver cells are able to reconstitute all hematopoietic compartments of lethally irradiated recipient mice. A developmental analysis of chimeras showed contribution of c-jun-/- ES cell derivatives to fetal, but not to adult livers, suggesting a role of c-Jun in hepatocyte turnover. This is in agreement with the reduced mitotic and increased apoptotic rates found in primary liver cell cultures derived from c-jun-/- fetuses. Furthermore, a novel function for c-Jun was found in heart development. The heart outflow tract of c-jun-/- fetuses show malformations that resemble the human disease of a truncus arteriosus persistens. Therefore, the lethality of c-jun mutant fetuses is most likely due to pleiotropic defects reflecting the diversity of functions of c-Jun in development, such as a role in neural crest cell function, in the maintenance of hepatic hematopoiesis and in the regulation of apoptosis.


Assuntos
Coração/embriologia , Coração/fisiologia , Fígado/embriologia , Fígado/fisiologia , Proteínas Proto-Oncogênicas c-jun/fisiologia , Fator de Transcrição AP-1/fisiologia , Animais , Apoptose , Desenvolvimento Embrionário e Fetal , Deleção de Genes , Células-Tronco Hematopoéticas/patologia , Células-Tronco Hematopoéticas/fisiologia , Fígado/patologia , Camundongos , Camundongos Knockout
7.
J Pathol ; 216(4): 495-504, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18850582

RESUMO

Endometrial stromal sarcomas are rare and molecular mechanisms involved in their pathogenesis are poorly understood. Covalent modifications of histone proteins, in particular de/acetylation of lysine residues, play an important role in the regulation of gene transcription in normal and neoplastic cells, but there are only limited data about these processes in solid mesenchymal tumours. We treated endometrial stromal sarcoma cells (ESS-1) and non-malignant human endometrial stromal cells (HESCs) with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor. SAHA was able to mediate the cell cycle and expression of genes related to the malignant phenotype of endometrial stromal tumours, eg p21(WAF1) and HDAC7. SAHA led to dose-dependent differentiation and death of ESS-1 cells but not of HESCs. Exposure of HESCs to SAHA resulted only in slightly decreased cell proliferation. SAHA also increased the p21(WAF1) expression and caused significant changes in the cell cycle by inhibiting the G1/S transition in ESS-1 cells. Recovery experiments indicated that these changes became irreversible when the tumour cells were treated with SAHA for longer than 24 h. In our experimental system, not apoptotic but autophagic processes were responsible for the cell death. Monodansyl cadaverine accumulation in treated ESS-1 cells and decreased expression of the mTOR and phospho-S6 ribosomal protein (S6rp) additionally supported this observation. Taken together, our study indicates that HDACs might be considered as potential drug targets in the therapy of stromal sarcomas and that SAHA might be a promising therapeutic agent for endometrial stromal sarcoma.


Assuntos
Neoplasias do Endométrio/tratamento farmacológico , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/uso terapêutico , Proteínas Quinases/metabolismo , Sarcoma do Estroma Endometrial/tratamento farmacológico , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias do Endométrio/patologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Histona Desacetilases/metabolismo , Humanos , Immunoblotting/métodos , Microscopia Eletrônica , Sarcoma do Estroma Endometrial/patologia , Serina-Treonina Quinases TOR , Vorinostat
8.
N Biotechnol ; 53: 35-40, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31202859

RESUMO

Comparison of published biomedical studies shows that a large proportion are irreproducible, causing severe damage to society and creating an image of wasted investments. These observations are of course damaging to the biomedical research field, which is currently full of future promise. Precision medicine and disease prevention are successful, but are progressing slowly due to irreproducible study results. Although standardization is mentioned as a possible solution, it is not always clear how this could decrease or prevent irreproducible results in biomedical studies. In this article more insight is given into what quality, norms, standardization, certification, accreditation and optimized infrastructure can accomplish to reveal causes of irreproducibility and increase reproducibility when collecting biomaterials. CEN and ISO standards for the sample pre-analytical phase are currently being developed with the support of the SPIDIA4P project, and their role in increasing reproducibility in both biomedical research and diagnostics is demonstrated. In particular, it is described how standardized methods and quality assurance documentation can be exploited as tools for: 1) recognition and rejection of 'not fit for purpose' samples on the basis of detailed sample metadata, and 2) identification of methods that contribute to irreproducibility which can be adapted or replaced.


Assuntos
Materiais Biocompatíveis/análise , Pesquisa Biomédica/normas , Fase Pré-Analítica/normas , Humanos , Reprodutibilidade dos Testes
9.
Br J Cancer ; 99(1): 151-9, 2008 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-18594539

RESUMO

To enable detailed analyses of cell interactions in tumour development, new epithelial and mesenchymal cell lines were established from human hepatocellular carcinoma by spontaneous outgrowth in culture. We obtained several hepatocarcinoma (HCC)-, B-lymphoblastoid (BLC)-, and myofibroblastoid (MF)-lines from seven cases. In-depth characterisation included cell kinetics, genotype, tumourigenicity, expression of cell-type specific markers, and proteome patterns. Many functions of the cells of origin were found to be preserved. We studied the impact of the mesenchymal lines on hepatocarcinogenesis by in vitro assays. BLC- and MF-supernatants strongly increased the DNA replication of premalignant hepatocytes. The stimulation by MF-lines was mainly attributed to HGF secretion. In HCC-cells, MF-supernatant had only minor effects on cell growth but enhanced migration. MF-lines also stimulated neoangiogenesis through vEGF release. BLC-supernatant dramatically induced death of HCC-cells, which could be largely abrogated by preincubating the supernatant with TNFbeta-antiserum. Thus, the new cell lines reveal stage-specific stimulatory and inhibitory interactions between mesenchymal and epithelial tumour cells. In conclusion, the new cell lines provide unique tools to analyse essential components of the complex interplay between the microenvironment and the developing liver cancer, and to identify factors affecting proliferation, migration and death of tumour cells, neoangiogenesis, and outgrowth of additional malignancy.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Comunicação Celular , Neoplasias Hepáticas/fisiopatologia , Animais , Linhagem Celular Tumoral , Células Epiteliais , Humanos , Camundongos , Ratos
10.
Pathologe ; 29 Suppl 2: 210-3, 2008 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-18810444

RESUMO

High quality human biological samples (e.g. blood, tissue or DNA) with associated, well documented clinical and research data are key resources for advancement of life sciences, biotechnology, clinical medicine, drug development and also molecular pathology. Millions of samples of diseased tissues have been collected in the context of routine histopathological diagnosis and are stored in the archives of hospitals and institutes of pathology. A concerted effort is necessary to overcome the current fragmentation of the European biobanking community in order to tap the full research potential of existing biobanks. A pan-European research infrastructure for biobanking and biomolecular resources (BBMRI) is currently in its planning phase. The mission is to link and provide access to local biobanks of different formats, including tissue collections, harmonize standards, establish operational procedures which properly consider ethical, legal, societal aspects, and to secure sustainable funding. Pathology plays a key role in development and administration of tissue banks and is, thus, a major partner for collaboration, expertise and construction of this pan-European research infrastructure.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Biotecnologia/organização & administração , Patologia Clínica , Pesquisa/organização & administração , Bancos de Tecidos/organização & administração , Biologia Computacional , Europa (Continente) , Humanos , Cooperação Internacional
11.
Pathobiology ; 74(4): 206-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17709961

RESUMO

Biobanks are a challenge and topic for governance. Today, biobanks are identified as a biomedical scientific/infrastructural development that warrants a political/legal/ethical reaction with the goal to integrate biobanks into the preexisting fabric of regulation, medicine, law and society. Biobank governance is always a response to sociocultural challenges and requires the building of trust, acceptance, and careful political negotiation. Biobanks are regulated in networks of governance in which the state is one actor next to others, and the ordering and structuring of the interaction between biobanks, society, and politics operates through a variety of actors, on different levels and along particular rationalities. Such networks of governance reflect, to some extent, a postregulatory state in which governance has become a complicated architecture and field of action involving a multitude of forces and rationalities. Biobank governance is still a relatively new field of political-legal intervention and it will be crucial for the future of biobanks to establish governance regimes that appropriately link research with society and politics.


Assuntos
Temas Bioéticos , Política de Saúde/tendências , Autonomia Pessoal , Saúde Pública , Bancos de Tecidos , Política de Saúde/legislação & jurisprudência , Humanos , Bancos de Tecidos/ética , Bancos de Tecidos/legislação & jurisprudência , Bancos de Tecidos/organização & administração
12.
Pathobiology ; 74(4): 251-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17709968

RESUMO

In the context of the Austrian Genome Program, a tissue bank is being established (Genome Austria Tissue Bank, GATiB) which is based on a collection of diseased and corresponding normal tissues representing a great variety of diseases at their natural frequency of occurrence from a non-selected Central European population of more than 700,000 patients. Major emphasis is put on annotation of archival tissue with comprehensive clinical data, including follow-up data. A specific IT infrastructure supports sample annotation, tracking of sample usage as well as sample and data storage. Innovative data protection tools were developed which prevent sample donor re-identification, particularly if detailed medical and genetic data are combined. For quality control of old archival tissues, new techniques were established to check RNA quality and antigen stability. Since 2003, GATiB has changed from a population-based tissue bank to a disease-focused biobank comprising major cancers such as colon, breast, liver, as well as metabolic liver diseases and organs affected by the metabolic syndrome. Prospectively collected tissues are associated with blood samples and detailed data on the sample donor's disease, lifestyle and environmental exposure, following standard operating procedures. Major emphasis is also placed on ethical, legal and social issues (ELSI) related to biobanks. A specific research project and an international advisory board ensure the proper embedding of GATiB in society and facilitate international networking.


Assuntos
Genoma , Bancos de Tecidos/organização & administração , Áustria , Bases de Dados Factuais , Humanos , Cooperação Internacional , Doenças Metabólicas/genética , Doenças Metabólicas/patologia , Neoplasias/genética , Neoplasias/patologia , Controle de Qualidade , Bancos de Tecidos/normas , Bancos de Tecidos/tendências
13.
Cancer Res ; 61(4): 1569-77, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11245467

RESUMO

Using subtractive technology, we have generated metastasis-associated gene expression profiles for rat mammary and pancreatic adenocarcinomas. Several genes whose expression is thought to be related to tumor progression such as c-Met, urokinase-type plasminogen activator receptor, ezrin, HMG-1, oncomodulin, cathepsin, and caveolin were thereby isolated. Half of the metastasis-associated clones showed no significant homology to genes with known function. Notably, several of the metastasis-associated clones were also expressed in metastatic lines but not in nonmetastatic lines of other tumor models. Furthermore, in situ hybridization using selected clones documents the relevance of these results for human cancer because strong expression in tumor cells including metastases was detected in human colorectal cancer samples and, to a lesser extent, in mammary cancer samples. These data support the concept that tumors express a "metastatic program" of genes.


Assuntos
Perfilação da Expressão Gênica , Neoplasias/genética , Neoplasias/patologia , Animais , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização In Situ , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Fenótipo , Ratos , Regulação para Cima
14.
Cell Death Differ ; 23(4): 576-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26470729

RESUMO

Hepatocellular carcinoma (HCC) develops as a consequence of chronic inflammatory liver diseases such as chronic hepatitis B virus (HBV) infection. The transcription factor c-Jun/activator protein 1 (AP-1) is strongly expressed in response to inflammatory stimuli, promotes hepatocyte survival during acute hepatitis and acts as an oncogene during chemically induced liver carcinogenesis in mice. Here, we therefore aimed to characterize the functions of c-Jun during HBV-related liver tumorigenesis. To this end, transgenic mice expressing all HBV envelope proteins (HBV(+)), an established model of HBV-related HCC, were crossed with knockout mice lacking c-Jun specifically in hepatocytes and tumorigenesis was analyzed. Hepatic expression of c-Jun was strongly induced at several time points during tumorigenesis in HBV(+) mice, whereas expression of other AP-1 components remained unchanged. Importantly, formation of premalignant foci and tumors was strongly reduced in HBV(+) mice lacking c-Jun. This phenotype correlated with impaired hepatocyte proliferation and increased expression of the cell cycle inhibitor p21, whereas hepatocyte survival was not affected. Progression and prognosis of HBV-related HCC correlates with the expression of the cytokine osteopontin (Opn), an established AP-1 target gene. Opn expression was strongly reduced in HBV(+) livers and primary mouse hepatocytes lacking c-Jun, demonstrating that c-Jun regulates hepatic Opn expression in a cell-autonomous manner. These findings indicate that c-Jun has important functions during HBV-associated tumorigenesis by promoting hepatocyte proliferation as well as progression of dysplasia. Therefore, targeting c-Jun may be a useful strategy to prevent hepatitis-associated tumorigenesis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transformação Celular Viral , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição AP-1/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Proliferação de Células/genética , Vírus da Hepatite B/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-jun/genética , Fator de Transcrição AP-1/genética
15.
J Mol Med (Berl) ; 77(10): 744-50, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10606210

RESUMO

Easy accessibility makes the skin extremely attractive for therapeutic gene transfer, but this feature may be equally responsible for inadvertent DNA uptake. Therefore we studied lacZ reporter gene expression after epicutaneous and intracutaneous administration of naked DNA, lipofection and transferrinfection to intact, tape-stripped, and wound-healing skin of hairless mice. Gold particles coated with 1 microg pCMVnlslacZ were inoculated with a gene gun as a positive control. Beta-galactosidase expression by skin cells, i.e., keratinocytes of the upper epithelial layers and single cells in the upper dermis, determined by X-Gal histochemistry was not observed except after ballistic gene transfer. By polymerase chain reaction we detected lacZ DNA after skin bombardment up to 4 weeks. After intracutaneous and epicutaneous application to normal and tape-stripped skin of the various delivery systems lacZ DNA was detectable up to 1 week. Epicutaneous application of the delivery systems to wounded skin resulted in lacZ DNA detectability up to 48 h only. Reverse-transcriptase polymerase chain reaction indicated transcription of the reporter gene after particle bombardment and intracutaneous injection, up to 48 h, but not after epicutaneous application of either delivery system. The possibility of inadvertent uptake of exogeneous DNA by intact and tape-stripped skin is evidenced by the detection of reporter gene DNA after epicutaneous application of naked DNA and DNA complexed to cationic lipids or transferrin-polylysine (transferrinfection). However, the effects of the presence and persistence of foreign genes in the target cells are not clear yet.


Assuntos
DNA Recombinante/farmacocinética , Pele/metabolismo , Administração Cutânea , Animais , Biolística , Resinas de Troca de Cátion , DNA Recombinante/administração & dosagem , Epiderme/lesões , Epiderme/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Terapia Genética/métodos , Queratinócitos/metabolismo , Óperon Lac , Lipídeos , Lipossomos , Masculino , Camundongos , Camundongos Pelados , Polilisina/análogos & derivados , RNA Mensageiro/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/lesões , Transferrina/análogos & derivados , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
16.
Hum Gene Ther ; 10(6): 983-93, 1999 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10223732

RESUMO

We performed a phase I trial to evaluate the safety and tolerability of repeated skin injections of IL-2-transfected autologous melanoma cells into patients with advanced disease. Cell suspensions, propagated from excised metastases, were IL-2 gene transfected by adenovirus-enhanced transferrinfection and X-irradiated prior to injection. Vaccine production was successful in 54% of the patients. Fifteen patients (37%) received two to eight skin vaccinations of either 3 x 10(6) (intradermal) or 1 x 10(7) (half intradermal, half subcutaneous) transfected melanoma cells per vaccination (secreting 140-17,060 biological response modifier program units of IL-2/10(6) cells/24 hr). Analyses of safety and efficacy were carried out in 15 and 14 patients, respectively. Overall, the vaccine was well tolerated. All patients displayed modest local reactions (erythema, induration, and pruritus) and some experienced flu-like symptoms. Apart from newly appearing (4 of 14) and increasing (5 of 14) anti-adenovirus and newly detectable anti-nuclear antibody titers (1 of 15), recipients developed de novo or exhibited increased melanoma cell-specific delayed-type hypersensitivity (DTH) reactions (8 of 15) and vitiligo (3 of 15) and showed signs of tumor regression (3 of 15). This supports the idea of a vaccine-induced or -amplified anti-cancer immune response. None of the patients exhibited complete or partial regressions, but five of them experienced periods of disease stabilization. Three of these individuals received more than the four planned vaccinations and their mean survival time was 15.7 +/- 3.5 months as compared to 7.8 +/- 4.6 months for the entire patient cohort. These data indicate that IL-2-producing, autologous cancer cells can be safely administered to stage IV melanoma patients and could conceivably be of benefit to patients with less advanced disease.


Assuntos
Vacinas Anticâncer/uso terapêutico , Melanoma/terapia , Neoplasias Cutâneas/terapia , Adulto , Idoso , Anticorpos Antineoplásicos/biossíntese , Anticorpos Antineoplásicos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/efeitos adversos , Feminino , Humanos , Hipersensibilidade Tardia , Injeções Intralesionais , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Cutâneas/patologia , Resultado do Tratamento
17.
Gene ; 135(1-2): 199-207, 1993 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8276260

RESUMO

The last few years have seen the development of a branch of somatic gene therapy which aims at strengthening the immune surveillance of the body, leading to eradication of disseminated cancer tumor cells and occult micrometastases after surgical removal of the primary tumor. Such a tumor vaccination protocol calls for cultivation of the primary tumor tissue and the insertion of one of three types of genes into the isolated cultured tumor cells followed by irradiation of the transfected or transduced cells to render them incapable of further proliferation. The cells so treated constitute the 'tumor vaccine'. A review of the literature suggests that for mouse models, in the initial period after inoculation, rejection of the tumor cells is usually effected by non-T-cell immunity, whereas the long-term systemic immune response is based on cytotoxic T-cells. High expression of the gene inserted into the tumor cells may be critical for the success of the vaccination procedure. Examples are given which indicate that transferrinfection, a procedure to introduce genes by adenovirus-augmented receptor-mediated endocytosis, meets some important prerequisites for successful application of this type of gene therapy.


Assuntos
Terapia Genética , Neoplasias/terapia , Vacinas Sintéticas/uso terapêutico , Animais , Humanos , Neoplasias/genética , Neoplasias/imunologia , Células Tumorais Cultivadas/transplante , Vacinas Sintéticas/imunologia
18.
Free Radic Biol Med ; 20(3): 263-70, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8720895

RESUMO

An apparent gradual decrease of IgG1 serum levels of up to 40% occurs within 48 h of storage at room temperature. The effect does not concern any other IgG subclass, and is more pronounced in sera of smokers. A linear correlation was found between the extent of this "storage effect" and the initial concentration of IgG1, which rules out an enzymatic process following Michaelis-Menten kinetics. PAGE and Western blots of density gradient separated serum proteins revealed the presence of noncovalent self aggregates of IgG1 in stored sera. Addition of superoxide dismutase prevented both the formation of aggregates as well as the decay of IgG1 values. It is concluded that the instability of IgG1 is due to an enhanced propensity of this molecule to form self-aggregates, whereby O2(-)-radicals play a functional role. This mechanism, however, is not relevant to a previously detected selective decrease of relative IgG1 levels in sera of patients afflicted with malignant diseases of various tissue origin.


Assuntos
Imunoglobulina G/sangue , Fumar/sangue , Superóxidos/sangue , Coleta de Amostras Sanguíneas , Neoplasias da Mama/sangue , Neoplasias da Mama/imunologia , Feminino , Neoplasias dos Genitais Femininos/sangue , Neoplasias dos Genitais Femininos/imunologia , Humanos , Imunoglobulina G/química , Imunoglobulina G/classificação , Cinética , Masculino , Valores de Referência , Fumar/imunologia , Fatores de Tempo
19.
Biotechniques ; 18(3): 484-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7779400

RESUMO

A new procedure is described for the generation of high-titer, helper-free retrovirus vectors employing receptor-mediated, adenovirus-augmented transfection into a standard packaging cell line. Viral titers are increased 30-fold to 100-fold in transiently (> 10(5) infectious units per mL) and stable (> 10(7) infectious units per mL) transfected cells as compared with either CaPO4-mediated transfection or retroviral infection of a packaging cell line. Further, expression of the transduced genes was drastically increased in the transfected cells, but, as expected, there was no difference in transduction efficiency and gene expression in the infected target cells. The increases in viral titers were most likely due to the high number of stable, integrated copies of the vector plasmid DNA in the resulting packaging lines following G418 selection. In addition, experiments generating recombinant retroviruses from non-packaging cell lines are presented. The results suggest that this procedure may be of use to generate high-titer retrovirus vectors in packaging cell lines as well as in primary cells, thus providing a technical basis for in vivo gene transfer upon transplantation of these cells into various organs.


Assuntos
Adenoviridae/genética , Vetores Genéticos/genética , Retroviridae/genética , Transfecção , Células 3T3 , Animais , Linhagem Celular , Receptores ErbB/genética , Receptores ErbB/metabolismo , Citometria de Fluxo , Camundongos , Receptores Virais/genética , Receptores Virais/metabolismo
20.
Int J Oncol ; 17(5): 1019-23, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11029507

RESUMO

The affinity of MCF7 breast cancer cells to hyaluronan (HA) was investigated in an in vitro model. The cells form a tightly adhering monolayer on native HA with a concentration of 5 mg/ml. On native HA at higher concentrations the cells reduce their adhesion to the substrate in favor of increased intercellular bonds, resulting in a cluster-like aggregate that tends to detach from the substrate. Aggregate formation is accomplished after 12 h incubation. The phenomenon is independent of the CD44 receptor. Degradation of native HA by hyaluronidase abolishes aggregate formation even at high HA concentrations in favor of formation of a firmly adhering monolayer. This model may help to understand tumor spread on HA tissue structures and may explain therapy successes with hyaluronidase in tumor patients.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Ácido Hialurônico/metabolismo , Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Adesão Celular/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Ácido Hialurônico/química , Hialuronoglucosaminidase/farmacologia , Microscopia Eletrônica de Varredura , Peso Molecular , Concentração Osmolar , Células Tumorais Cultivadas/efeitos dos fármacos
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