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1.
J Virol ; 90(19): 8563-74, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27440883

RESUMO

UNLABELLED: In chronic hepatitis B (CHB), failure to control hepatitis B virus (HBV) is associated with T cell dysfunction. HBV transgenic mice mirror many features of the human disease, including T cell unresponsiveness, and thus represent an appropriate model in which to test novel therapeutic strategies. To date, the tolerant state of CD8(+) T cells in these animals could be altered only by strong immunogens or by immunization with HBV antigen-pulsed dendritic cells; however, the effectors induced were unable to suppress viral gene expression or replication. Because of the known stimulatory properties of alpha interferon (IFN-α) and interleukin-15 (IL-15), this study explored the therapeutic potential of liver-directed gene transfer of these cytokines in a murine model of CHB using adeno-associated virus (AAV) delivery. This combination not only resulted in a reduction in the viral load in the liver and the induction of an antibody response but also gave rise to functional and specific CD8(+) immunity. Furthermore, when splenic and intrahepatic lymphocytes from IFN-α- and IL-15-treated animals were transferred to new HBV carriers, partial antiviral immunity was achieved. In contrast to previous observations made using either cytokine alone, markedly attenuated PD-L1 induction in hepatic tissue was observed upon coadministration. An initial study with CHB patient samples also gave promising results. Hence, we demonstrated synergy between two stimulating cytokines, IL-15 and IFN-α, which, given together, constitute a potent approach to significantly enhance the CD8(+) T cell response in a state of immune hyporesponsiveness. Such an approach may be useful for treating chronic viral infections and neoplastic conditions. IMPORTANCE: With 350 million people affected worldwide and 600,000 annual deaths due to HBV-induced liver cirrhosis and/or hepatocellular carcinoma, chronic hepatitis B (CHB) is a major health problem. However, current treatment options are costly and not very effective and/or need to be administered for life. The unprecedented efficacy of the strategy described in our paper may offer an alternative and is relevant for a broad spectrum of readers because of its clear translational importance to other chronic viral infections in which a hyporesponsive antigen-specific T cell repertoire prevents clearance of the pathogen.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Interferon-alfa/administração & dosagem , Interleucina-15/administração & dosagem , Adenoviridae/genética , Animais , Modelos Animais de Doenças , Portadores de Fármacos , Terapia Genética , Anticorpos Anti-Hepatite B/sangue , Interferon-alfa/genética , Interleucina-15/genética , Fígado/virologia , Camundongos Transgênicos , Resultado do Tratamento , Carga Viral
2.
Clin Cancer Res ; 20(6): 1542-54, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24486586

RESUMO

PURPOSE: MLN9708 (ixazomib citrate), which hydrolyzes to pharmacologically active MLN2238 (ixazomib), is a next-generation proteasome inhibitor with demonstrated preclinical and clinical antimyeloma activity, but yet with an unknown effect on myeloma bone disease. Here, we investigated its bone anabolic and antiresorptive effects in the myeloma setting and in comparison with bortezomib in preclinical models. EXPERIMENTAL DESIGN: The in vitro effect of MLN2238 was tested on osteoclasts and osteoclast precursors from healthy donors and patients with myeloma, and on osteoprogenitors derived from bone marrow mesenchymal stem cells also from both origins. We used an in vivo model of bone marrow-disseminated human myeloma to evaluate MLN2238 antimyeloma and bone activities. RESULTS: Clinically achievable concentrations of MLN2238 markedly inhibited in vitro osteoclastogenesis and osteoclast resorption; these effects involved blockade of RANKL (receptor activator of NF-κB ligand)-induced NF-κB activation, F-actin ring disruption, and diminished expression of αVß3 integrin. A similar range of MLN2238 concentrations promoted in vitro osteoblastogenesis and osteoblast activity (even in osteoprogenitors from patients with myeloma), partly mediated by activation of TCF/ß-catenin signaling and upregulation of the IRE1 component of the unfolded protein response. In a mouse model of bone marrow-disseminated human multiple myeloma, orally administered MLN2238 was equally effective as bortezomib to control tumor burden and also provided a marked benefit in associated bone disease (sustained by both bone anabolic and anticatabolic activities). CONCLUSION: Given favorable data on pharmacologic properties and emerging clinical safety profile of MLN9708, it is conceivable that this proteasome inhibitor may achieve bone beneficial effects in addition to its antimyeloma activity in patients with myeloma.


Assuntos
Compostos de Boro/farmacologia , Glicina/análogos & derivados , Mieloma Múltiplo/metabolismo , Osteoclastos/efeitos dos fármacos , Inibidores de Proteassoma/farmacologia , Animais , Antineoplásicos/farmacologia , Reabsorção Óssea/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Glicina/farmacologia , Humanos , Immunoblotting , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Osteoclastos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
PLoS One ; 8(9): e74948, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086405

RESUMO

It has been shown that the liver of immunodeficient mice can be efficiently repopulated with human hepatocytes when subjected to chronic hepatocellular damage. Mice with such chimeric livers represent useful reagents for medical and clinical studies. However all previously reported models of humanized livers are difficult to implement as they involve cross-breeding of immunodeficient mice with mice exhibiting genetic alterations causing sustained hepatic injury. In this paper we attempted to create chimeric livers by inducing persistent hepatocellular damage in immunodeficient Rag2(-/-) γc(-/-) mice using an adenovirus encoding herpes virus thymidine kinase (AdTk) and two consecutive doses of ganciclovir (GCV). We found that this treatment resulted in hepatocellular damage persisting for at least 10 weeks and enabled efficient engraftment and proliferation within the liver of either human or allogenic hepatocytes. Interestingly, while the nodules generated from the transplanted mouse hepatocytes were well vascularized, the human hepatocytes experienced progressive depolarization and exhibited reduced numbers of murine endothelial cells inside the nodules. In conclusion, AdTk/GCV-induced liver damage licenses the liver of immunodeficient mice for allogenic and xenogenic hepatocyte repopulation. This approach represents a simple alternative strategy for chimeric liver generation using immunodeficient mice without additional genetic manipulation of the germ line.


Assuntos
Adenoviridae/metabolismo , Hepatócitos/transplante , Fígado/patologia , Timidina Quinase/metabolismo , Transplante Heterólogo , Albuminas/metabolismo , Animais , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Ganciclovir/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Hepatite B/patologia , Hepatite C/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante Homólogo
4.
J Lipid Res ; 53(12): 2791-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22993232

RESUMO

The accurate estimation of the number and size of cells provides relevant information on the kinetics of growth and the physiological status of a given tissue or organ. Here, we present Adiposoft, a fully automated open-source software for the analysis of white adipose tissue cellularity in histological sections. First, we describe the sequence of image analysis routines implemented by the program. Then, we evaluate our software by comparing it with other adipose tissue quantification methods, namely, with the manual analysis of cells in histological sections (used as gold standard) and with the automated analysis of cells in suspension, the most commonly used method. Our results show significant concordance between Adiposoft and the other two methods. We also demonstrate the ability of the proposed method to distinguish the cellular composition of three different rat fat depots. Moreover, we found high correlation and low disagreement between Adiposoft and the manual delineation of cells. We conclude that Adiposoft provides accurate results while considerably reducing the amount of time and effort required for the analysis.


Assuntos
Tecido Adiposo Branco/citologia , Automação , Software , Animais , Masculino , Ratos , Ratos Wistar
5.
Stud Health Technol Inform ; 121: 242-56, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17095823

RESUMO

When using a number of medical devices from very different manufacturers with different proprietary formats the problem of a lack of interoperability emerges. Connectivity and communications are then limited and the systems and users can not exploit all the possibilities that Information and Communication Technologies offer today. The use and application of standards can be the solution to bring light to this confusion of languages in this Tower of Babel. There are several standards applicable to medical information systems interoperability and, analyzing these different options, the X73 PoC-MDC (ISO11073/IEEE1073) set of standards for Point of Care Medical Device Communication is the best positioned international standard to provide interoperability in these communications.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Equipamentos e Provisões , Sistemas de Informação Hospitalar/normas , Sistemas Computadorizados de Registros Médicos/normas , Integração de Sistemas , Telemetria/instrumentação , Redes de Comunicação de Computadores/normas , Humanos , Sistemas Integrados e Avançados de Gestão da Informação , Padrões de Referência , Espanha
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