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1.
Nanomedicine ; 36: 102419, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34147665

RESUMO

In this study we produced a set of in vitro culture platforms to model vascular cell responses to growth factors and factor delivery vehicles. Two of the systems (whole vessel and whole lung vascular development) were supported by microfluidic systems facilitating media circulation and waste removal. We assessed vascular endothelial growth factor (VEGF) delivery by Pluronic F-127 hydrogel, 30 nm pore-sized microparticles (MPs), 60 nm pore-sized MP or a 50/50 mixture of 30 and 60 nm pore-sized MP. VEGF was delivered to porcine acellular lung vascular scaffolds (2.5 cm2 square pieces or whole 3D segments of acellular blood vessels) as well as whole acellular lung scaffolds. Scaffold-cell attachment was examined as was vascular tissue formation. We showed that a 50/50 mixture of 30 and 60 nm pore-sized silicon wafer MPs allowed for long-term release of VEGF within the scaffold vasculature and supported vascular endothelial tissue development during in vitro culture.


Assuntos
Portadores de Fármacos , Células Endoteliais/metabolismo , Hidrogéis , Pulmão , Neovascularização Fisiológica/efeitos dos fármacos , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular , Animais , Técnicas de Cultura de Células , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Pulmão/irrigação sanguínea , Pulmão/química , Porosidade , Suínos , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/farmacocinética , Fator A de Crescimento do Endotélio Vascular/farmacologia
2.
Biomed Microdevices ; 21(2): 47, 2019 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-31104136

RESUMO

Chronic diseases account for the majority of all deaths worldwide, and their prevalence is expected to escalate in the next 10 years. Because chronic disorders require long-term therapy, the healthcare system must address the needs of an increasing number of patients. The use of new drug administration routes, specifically implantable drug delivery devices, has the potential to reduce treatment-monitoring clinical visits and follow-ups with healthcare providers. Also, implantable drug delivery devices can be designed to maintain drug concentrations in the therapeutic window to achieve controlled, continuous release of therapeutics over extended periods, eliminating the risk of patient non-compliance to oral treatment. A higher local drug concentration can be achieved if the device is implanted in the affected tissue, reducing systemic adverse side effects and decreasing the challenges and discomfort of parenteral treatment. Although implantable drug delivery devices have existed for some time, interest in their therapeutic potential is growing, with a global market expected to reach over $12 billion USD by 2018. This review discusses implantable drug delivery technologies in an advanced stage of development or in clinical use and focuses on the state-of-the-art of reservoir-based implants including pumps, electromechanical systems, and polymers, sites of implantation and side effects, and deployment in developing countries.


Assuntos
Doença Crônica/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Próteses e Implantes , Países em Desenvolvimento , Sistemas de Liberação de Medicamentos/instrumentação , Humanos , Microtecnologia , Polímeros/química
3.
Aviat Space Environ Med ; 83(11): 1025-36, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23156089

RESUMO

One purpose of the International Space Station (ISS) is to explore powerful new areas of biomedical science in microgravity. Recent advances in nanotechnology applied to medicine--what we now refer to as nano-medicine--and regenerative medicine have enormous untapped potential for future space and terrestrial medical applications. Novel means for drug delivery and nanoscale screening tools will one day benefit astronauts venturing to Mars and places beyond, while the space laboratory will foster advances in nanotechnologies for diagnostic and therapeutic tools to help our patients here on Earth. Herein we review a series of nanotechnologies and selected regenerative medical approaches and highlight key areas of ongoing and future investigation that will benefit both space and terrestrial medicine. These studies target significant areas of human disease such as osteoporosis, diabetes, radiation injury, and many others.


Assuntos
Medicina Aeroespacial , Nanotecnologia , Medicina Regenerativa , Sistemas de Liberação de Medicamentos , Coração , Humanos , Espectrometria de Massas , Membranas Artificiais , Nanoestruturas , Proteínas/química , Proteômica , Alicerces Teciduais
4.
Pharmacol Res ; 62(2): 57-89, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20045055

RESUMO

Individualized medicine is the healthcare strategy that rebukes the idiomatic dogma of 'losing sight of the forest for the trees'. We are entering a new era of healthcare where it is no longer acceptable to develop and market a drug that is effective for only 80% of the patient population. The emergence of "-omic" technologies (e.g. genomics, transcriptomics, proteomics, metabolomics) and advances in systems biology are magnifying the deficiencies of standardized therapy, which often provide little treatment latitude for accommodating patient physiologic idiosyncrasies. A personalized approach to medicine is not a novel concept. Ever since the scientific community began unraveling the mysteries of the genome, the promise of discarding generic treatment regimens in favor of patient-specific therapies became more feasible and realistic. One of the major scientific impediments of this movement towards personalized medicine has been the need for technological enablement. Nanotechnology is projected to play a critical role in patient-specific therapy; however, this transition will depend heavily upon the evolutionary development of a systems biology approach to clinical medicine based upon "-omic" technology analysis and integration. This manuscript provides a forward looking assessment of the promise of nanomedicine as it pertains to individualized medicine and establishes a technology "snapshot" of the current state of nano-based products over a vast array of clinical indications and range of patient specificity. Other issues such as market driven hurdles and regulatory compliance reform are anticipated to "self-correct" in accordance to scientific advancement and healthcare demand. These peripheral, non-scientific concerns are not addressed at length in this manuscript; however they do exist, and their impact to the paradigm shifting healthcare transformation towards individualized medicine will be critical for its success.


Assuntos
Nanotecnologia/métodos , Medicina de Precisão/métodos , Animais , Humanos , Nanomedicina/métodos , Nanomedicina/tendências , Nanotecnologia/tendências , Medicina de Precisão/tendências , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências
5.
Biomed Microdevices ; 11(1): 49-63, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18663578

RESUMO

Breast cancer is the field of medicine with the greatest presence of nanotechnological therapeutic agents in the clinic. A pegylated form of liposomally encapsulated doxorubicin is routinely used for treatment against metastatic cancer, and albumin nanoparticulate chaperones of paclitaxel were approved for locally recurrent and metastatic disease in 2005. These drugs have yielded substantial clinical benefit, and are steadily gathering greater beneficial impact. Clinical trials currently employing these drugs in combination with chemo and biological therapeutics exceed 150 worldwide. Despite these advancements, breast cancer morbidity and mortality is unacceptably high. Nanotechnology offers potential solutions to the historical challenge that has rendered breast cancer so difficult to contain and eradicate: the extreme biological diversity of the disease presentation in the patient population and in the evolutionary changes of any individual disease, the multiple pathways that drive disease progression, the onset of 'resistance' to established therapeutic cocktails, and the gravity of the side effects to treatment, which result from generally very poor distribution of the injected therapeutic agents in the body. A fundamental requirement for success in the development of new therapeutic strategies is that breast cancer specialists-in the clinic, the pharmaceutical and the basic biological laboratory-and nanotechnologists-engineers, physicists, chemists and mathematicians-optimize their ability to work in close collaboration. This further requires a mutual openness across cultural and language barriers, academic reward systems, and many other 'environmental' divides. This paper is respectfully submitted to the community to help foster the mutual interactions of the breast cancer world with micro- and nano-technology, and in particular to encourage the latter community to direct ever increasing attention to breast cancer, where an extraordinary beneficial impact may result. The paper initiates with an introductory overview of breast cancer, its current treatment modalities, and the current role of nanotechnology in the clinic. Our perspectives are then presented on what the greatest opportunities for nanotechnology are; this follows from an analysis of the role of biological barriers that adversely determine the biological distribution of intravascularly injected therapeutic agents. Different generations of nanotechnology tools for drug delivery are reviewed, and our current strategy for addressing the sequential bio-barriers is also presented, and is accompanied by an encouragement to the community to develop even more effective ones.


Assuntos
Neoplasias da Mama/terapia , Nanotecnologia/métodos , Feminino , Humanos
6.
Sci Transl Med ; 10(452)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068570

RESUMO

The inability to produce perfusable microvasculature networks capable of supporting tissue survival and of withstanding physiological pressures without leakage is a fundamental problem facing the field of tissue engineering. Microvasculature is critically important for production of bioengineered lung (BEL), which requires systemic circulation to support tissue survival and coordination of circulatory and respiratory systems to ensure proper gas exchange. To advance our understanding of vascularization after bioengineered organ transplantation, we produced and transplanted BEL without creation of a pulmonary artery anastomosis in a porcine model. A single pneumonectomy, performed 1 month before BEL implantation, provided the source of autologous cells used to bioengineer the organ on an acellular lung scaffold. During 30 days of bioreactor culture, we facilitated systemic vessel development using growth factor-loaded microparticles. We evaluated recipient survival, autograft (BEL) vascular and parenchymal tissue development, graft rejection, and microbiome reestablishment in autografted animals 10 hours, 2 weeks, 1 month, and 2 months after transplant. BEL became well vascularized as early as 2 weeks after transplant, and formation of alveolar tissue was observed in all animals (n = 4). There was no indication of transplant rejection. BEL continued to develop after transplant and did not require addition of exogenous growth factors to drive cell proliferation or lung and vascular tissue development. The sterile BEL was seeded and colonized by the bacterial community of the native lung.


Assuntos
Engenharia Biomédica , Transplante de Pulmão , Animais , Regulação da Expressão Gênica , Imunidade , Pulmão/crescimento & desenvolvimento , Pulmão/imunologia , Pulmão/ultraestrutura , Linfangiogênese/genética , Microbiota , Modelos Animais , Suínos , Alicerces Teciduais/química , Transcriptoma/genética
7.
Med Clin North Am ; 91(5): 899-927, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17826110

RESUMO

Nanotechnology may hold the key to controlling many devastating diseases. In the fight against the pain, suffering, and death due to cancer, nanotechnology will allow earlier diagnosis and even prevention of malignancy at premalignant stages, in addition to providing multimodality treatment not possible with current conventional techniques. This review discusses nanotechnology already used in diagnostic and therapeutic applications for cancer. Also addressed are theoretic and evolving uses of nanotechnology, including multifunctional nanoparticles for imaging and therapy, nanochannel implants for controlled release of drugs, nanoscale devices for evaluation of proteomics and genomics, and diagnostic techniques that take advantage of physical changes in diseased tissue.


Assuntos
Antineoplásicos/uso terapêutico , Nanomedicina/métodos , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Humanos , Prognóstico
8.
Expert Opin Drug Deliv ; 4(4): 359-69, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17683250

RESUMO

The advent of sophisticated drug delivery strategies for cancer applications has inundated the scientific and clinical community with new tactics and approaches such as molecular targeting, nanotechnology-based methods and personalized therapies. Unfortunately, the clinical impact has been moderate at best, falling significantly short from revolutionizing existing chemotherapeutic methodologies. To this day, a cancer patient has a higher probability of receiving traditional systemically administered drugs than a more sophisticated targeted or nanotechnology-based therapeutic. This is not a reflection upon the novelty or quality of the technologies, but an indication of opportunity for a new approach that offers the realisation of the full potential of these scientific advances. This approach acknowledges the significance of the numerous biological barriers presented in the human body and their sequential nature. It is then recommended that computational mathematical tools are used to predict which nanovectors, surface modifications, therapeutic agents and penetration enhancers to use for a multi-stage drug delivery strategy. An approach where several stages of micro-/nano-vectors are nested within each other and delivered to overcome specific biological barriers to ultimately release a concentrated dose of a therapeutic payload at the intended lesion site. This novel, multi-stage strategy enables efficient localised delivery of chemotoxic drugs that may lead to significant improvements in therapy efficacy, reduced systemic toxicity and decreased total amount of injected drugs.


Assuntos
Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Desenho de Fármacos , Nanotecnologia , Neoplasias/metabolismo , Tecnologia Farmacêutica/métodos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Química Farmacêutica , Biologia Computacional , Difusão de Inovações , Vias de Administração de Medicamentos , Portadores de Fármacos , Composição de Medicamentos , Humanos , Modelos Biológicos , Neoplasias/tratamento farmacológico
9.
J Tissue Eng Regen Med ; 11(7): 2136-2152, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-26756722

RESUMO

We report, for the first time, the development of an organ culture system and protocols to support recellularization of whole acellular (AC) human paediatric lung scaffolds. The protocol for paediatric lung recellularization was developed using human transformed or immortalized cell lines and single human AC lung scaffolds. Using these surrogate cell populations, we identified cell number requirements, cell type and order of cell installations, flow rates and bioreactor management methods necessary for bioengineering whole lungs. Following the development of appropriate cell installation protocols, paediatric AC scaffolds were recellularized using primary lung alveolar epithelial cells (AECs), vascular cells and tracheal/bronchial cells isolated from discarded human adult lungs. Bioengineered paediatric lungs were shown to contain well-developed vascular, respiratory epithelial and lung tissue, with evidence of alveolar-capillary junction formation. Types I and II AECs were found thoughout the paediatric lungs. Furthermore, surfactant protein-C and -D and collagen I were produced in the bioengineered lungs, which resulted in normal lung compliance measurements. Although this is a first step in the process of developing tissues for transplantation, this study demonstrates the feasibility of producing bioengineered lungs for clinical use. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Células Epiteliais Alveolares/metabolismo , Bioprótese , Reatores Biológicos , Pulmão/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Células Epiteliais Alveolares/citologia , Animais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
10.
J Tissue Eng ; 7: 2041731415626018, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26977287

RESUMO

Surgical wound healing applications require bioprosthetics that promote cellular infiltration and vessel formation, metrics associated with increased mechanical strength and resistance to infection. Porcine acellular lung matrix is a novel tissue scaffold known to promote cell adherence while minimizing inflammatory reactions. In this study, we evaluate the capacity of porcine acellular lung matrix to sustain cellularization and neovascularization in a rat model of subcutaneous implantation and chronic hernia repair. We hypothesize that, compared to human acellular dermal matrix, porcine acellular lung matrix would promote greater cell infiltration and vessel formation. Following pneumonectomy, porcine lungs were processed and characterized histologically and by scanning electron microscopy to demonstrate efficacy of the decellularization. Using a rat model of subcutaneou implantation, porcine acellular lung matrices (n = 8) and human acellular dermal matrices (n = 8) were incubated in vivo for 6 weeks. To evaluate performance under mechanically stressed conditions, porcine acellular lung matrices (n = 7) and human acellular dermal matrices (n = 7) were implanted in a rat model of chronic ventral incisional hernia repair for 6 weeks. After 6 weeks, tissues were evaluated using hematoxylin and eosin and Masson's trichrome staining to quantify cell infiltration and vessel formation. Porcine acellular lung matrices were shown to be successfully decellularized. Following subcutaneous implantation, macroscopic vessel formation was evident. Porcine acellular lung matrices demonstrated sufficient incorporation and showed no evidence of mechanical failure after ventral hernia repair. Porcine acellular lung matrices demonstrated significantly greater cellular density and vessel formation when compared to human acellular dermal matrix. Vessel sizes were similar across all groups. Cell infiltration and vessel formation are well-characterized metrics of incorporation associated with improved surgical outcomes. Porcine acellular lung matrices are a novel class of acellular tissue scaffold. The increased cell and vessel density may promote long-term improved incorporation and mechanical properties. These findings may be due to the native lung scaffold architecture guiding cell migration and vessel formation. Porcine acellular lung matrices represent a new alternative for surgical wound healing applications where increased cell density and vessel formation are sought.

11.
Technol Cancer Res Treat ; 4(6): 627-36, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16292882

RESUMO

This study was structured to challenge the hypothesis that nano-sized particulates could be molecularly targeted and bound to the prognostic and predictive HER-2/neu cell membrane receptor to elicit detectable changes in ultrasound response from human breast cancer cells. SKBR-3 human breast cancer cells were enlisted to test the efficacy of the particle conjugation strategy used in this study and ultimately, to provide conclusive remarks regarding the validity of the stated hypothesis. A characterization-mode ultrasound (CMUS) system was used to apply a continuum mechanics based, two-step inversion algorithm to reconstruct the mechanical material properties of four cell/agarose test conditions upon three independent test samples. The four test conditions include: Herceptin conjugated iron oxide nanoparticles bound to cells (HER-con), Herceptin bound to cells (HER), iso-type matched antibody conjugated iron oxide nanoparticles bound to cells (ISO-con), and Cold Flow Buffer mixed with agarose (CFB). The statistical analysis of these ultrasound results supported the ability to differentiate between HER-2/neu positive SKBR-3 cells that have been successfully tagged with Herceptin(R) conjugated iron oxide particles to those that have not demonstrated particle binding. These findings serve as promising proof-of-concept data for the development of a quantitative histopathologic evaluation tool directed towards both in situ and in vivo applications. The ultimate goal of this research is to exploit the molecular expression of the HER-2/neu protein to offer rapid, quantitative ultrasound information concerning the malignancy rating of human breast tissue employing tumor targeting nanoparticle based ultrasound contrast agents. When fully developed, this could potentially help 32,000-63,000 women efficiently find their proper treatment strategy to fight and win their battle against breast cancer.


Assuntos
Anticorpos Monoclonais , Neoplasias da Mama/diagnóstico , Meios de Contraste , Compostos Férricos , Receptor ErbB-2/metabolismo , Algoritmos , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/metabolismo , Feminino , Citometria de Fluxo , Humanos , Microscopia de Fluorescência , Nanoestruturas , Trastuzumab , Células Tumorais Cultivadas
12.
Curr Drug Targets ; 16(13): 1531-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26201489

RESUMO

Acute lung injury (ALI) and its most severe manifestation, acute respiratory distress syndrome (ARDS), is a clinical syndrome defined by acute hypoxemic respiratory failure and bilateral pulmonary infiltrates consistent with edema. In-hospital mortality is 38.5% for AL, and 41.1% for ARDS. Activation of alveolar macrophages in the donor lung causes the release of pro-inflammatory chemokines and cytokines, such as TNF-α. To determine the relevance of TNF-α in disrupting bronchial endothelial cell function, we stimulated human THP-1 macrophages with lipopolysaccharide (LPS) and used the resulting cytokine-supplemented media to disrupt normal endothelial cell functions. Endothelial tube formation was disrupted in the presence of LPS-activated THP- 1 conditioned media, with reversal of the effect occurring in the presence of 0.1µg/ml Enbrel, indicating that TNF-α was the major serum component inhibiting endothelial tube formation. To facilitate lung conditioning, we tested liposomal and porous silicon (pSi) delivery systems for their ability to selectively silence TNFR1 using siRNA technology. Of the three types of liposomes tested, only cationic liposomes had substantial endothelial uptake, with human cells taking up 10-fold more liposomes than their pig counterparts; however, non-specific cellular activation prohibited their use as immunosuppressive agents. On the other hand, pSi microparticles enabled the accumulation of large amounts of siRNA in endothelial cells compared to standard transfection with Lipofectamine(®) LTX, in the absence of non-specific activation of endothelia. Silencing of TNFR1 decreased TNF-α mediated inhibition of endothelial tube formation, as well as TNF-α-induced upregulation of ICAM-1, VCAM, and E-selection in human lung microvascular endothelial cells.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , RNA Interferente Pequeno/administração & dosagem , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Síndrome do Desconforto Respiratório/fisiopatologia , Animais , Cátions/metabolismo , Citocinas/metabolismo , Selectina E/genética , Células Endoteliais/metabolismo , Inativação Gênica , Humanos , Molécula 1 de Adesão Intercelular/genética , Lipopolissacarídeos/farmacologia , Lipossomos , Macrófagos/metabolismo , Microvasos/citologia , Microvasos/metabolismo , Especificidade da Espécie , Suínos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/genética , Molécula 1 de Adesão de Célula Vascular/genética
13.
J Control Release ; 194: 113-21, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25180449

RESUMO

There is an unmet clinical need to increase lung transplant successes, patient satisfaction and to improve mortality rates. We offer the development of a nanovector-based solution that will reduce the incidence of lung ischemic reperfusion injury (IRI) leading to graft organ failure through the successful ex vivo treatment of the lung prior to transplantation. The innovation is in the integrated application of our novel porous silicon (pSi) microparticles carrying adeno-associated virus (AAV) nanoparticles, and the use of our ex vivo lung perfusion/ventilation system for the modulation of pro-inflammatory cytokines initiated by ischemic pulmonary conditions prior to organ transplant that often lead to complications. Gene delivery of anti-inflammatory agents to combat the inflammatory cascade may be a promising approach to prevent IRI following lung transplantation. The rationale for the device is that the microparticle will deliver a large payload of virus to cells and serve to protect the AAV from immune recognition. The microparticle-nanoparticle hybrid device was tested both in vitro on cell monolayers and ex vivo using either porcine venous tissue or a pig lung transplantation model, which recapitulates pulmonary IRI that occurs clinically post-transplantation. Remarkably, loading AAV vectors into pSi microparticles increases gene delivery to otherwise non-permissive endothelial cells.


Assuntos
Vasos Sanguíneos/metabolismo , Dependovirus/imunologia , Técnicas de Transferência de Genes , Nanopartículas/química , Silício/química , Animais , Vasos Sanguíneos/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Expressão Gênica , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Tamanho da Partícula , Suínos , Veias/imunologia , Veias/virologia
14.
Transplant Res ; 3(1): 19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25671090

RESUMO

BACKGROUND: Primary graft dysfunction (PGD) is a significant cause of early morbidity and mortality following lung transplantation. Improved organ preservation techniques will decrease ischemia-reperfusion injury (IRI) contributing to PGD. Adult bone marrow-derived adherent stem cells, including mesenchymal stromal (stem) cells (MSCs) and multipotent adult progenitor cells (MAPCs), have potent anti-inflammatory actions, and we thus postulated that intratracheal MAPC administration during donor lung processing would decrease IRI. The goal of the study was therefore to determine if intratracheal MAPC instillation would decrease lung injury and inflammation in an ex vivo human lung explant model of prolonged cold storage and subsequent reperfusion. METHODS: Four donor lungs not utilized for transplant underwent 8 h of cold storage (4°C). Following rewarming for approximately 30 min, non-HLA-matched allogeneic MAPCs (1 × 10(7) MAPCs/lung) were bronchoscopically instilled into the left lower lobe (LLL) and vehicle comparably instilled into the right lower lobe (RLL). The lungs were then perfused and mechanically ventilated for 4 h and subsequently assessed for histologic injury and for inflammatory markers in bronchoalveolar lavage fluid (BALF) and lung tissue. RESULTS: All LLLs consistently demonstrated a significant decrease in histologic and BALF inflammation compared to vehicle-treated RLLs. CONCLUSIONS: These initial pilot studies suggest that use of non-HLA-matched allogeneic MAPCs during donor lung processing can decrease markers of cold ischemia-induced lung injury.

15.
Tissue Eng Part A ; 19(17-18): 2045-62, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23638920

RESUMO

The authors have previously shown that acellular (AC) trachea-lung scaffolds can (1) be produced from natural rat lungs, (2) retain critical components of the extracellular matrix (ECM) such as collagen-1 and elastin, and (3) be used to produce lung tissue after recellularization with murine embryonic stem cells. The aim of this study was to produce large (porcine or human) AC lung scaffolds to determine the feasibility of producing scaffolds with potential clinical applicability. We report here the first attempt to produce AC pig or human trachea-lung scaffold. Using a combination of freezing and sodium dodecyl sulfate washes, pig trachea-lungs and human trachea-lungs were decellularized. Once decellularization was complete we evaluated the structural integrity of the AC lung scaffolds using bronchoscopy, multiphoton microscopy (MPM), assessment of the ECM utilizing immunocytochemistry and evaluation of mechanics through the use of pulmonary function tests (PFTs). Immunocytochemistry indicated that there was loss of collagen type IV and laminin in the AC lung scaffold, but retention of collagen-1, elastin, and fibronectin in some regions. MPM scoring was also used to examine the AC lung scaffold ECM structure and to evaluate the amount of collagen I in normal and AC lung. MPM was used to examine the physical arrangement of collagen-1 and elastin in the pleura, distal lung, lung borders, and trachea or bronchi. MPM and bronchoscopy of trachea and lung tissues showed that no cells or cell debris remained in the AC scaffolds. PFT measurements of the trachea-lungs showed no relevant differences in peak pressure, dynamic or static compliance, and a nonrestricted flow pattern in AC compared to normal lungs. Although there were changes in content of collagen I and elastin this did not affect the mechanics of lung function as evidenced by normal PFT values. When repopulated with a variety of stem or adult cells including human adult primary alveolar epithelial type II cells both pig and human AC scaffolds supported cell attachment and cell viability. Examination of scaffolds produced using a variety of detergents indicated that detergent choice influenced human immune response in terms of T cell activation and chemokine production.


Assuntos
Pulmão , Alicerces Teciduais/química , Animais , Colágeno/química , Humanos , Imuno-Histoquímica , Laminina/química , Suínos , Engenharia Tecidual/métodos
16.
Clin Cancer Res ; 19(7): 1806-15, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23386691

RESUMO

PURPOSE: RNA interference has the potential to specifically knockdown the expression of target genes and thereby transform cancer therapy. However, lack of effective delivery of siRNA has dramatically limited its in vivo applications. We have developed a multistage vector (MSV) system, composed of discoidal porous silicon particles loaded with nanotherapeutics, that directs effective delivery and sustained release of siRNA in tumor tissues. In this study, we evaluated therapeutic efficacy of MSV-loaded EphA2 siRNA (MSV/EphA2) with murine orthotopic models of metastatic ovarian cancers as a first step toward development of a new class of nanotherapeutics for the treatment of ovarian cancer. EXPERIMENTAL DESIGN: Tumor accumulation of MSV/EphA2 and sustained release of siRNA from MSV were analyzed after intravenous administration of MSV/siRNA. Nude mice with metastatic SKOV3ip2 tumors were treated with MSV/EphA2 and paclitaxel, and therapeutic efficacy was assessed. Mice with chemotherapy-resistant HeyA8 ovarian tumors were treated with a combination of MSV/EphA2 and docetaxel, and enhanced therapeutic efficacy was evaluated. RESULTS: Treatment of SKOV3ip2 tumor mice with MSV/EphA2 biweekly for 6 weeks resulted in dose-dependent (5, 10, and 15 µg/mice) reduction of tumor weight (36%, 64%, and 83%) and number of tumor nodules compared with the control groups. In addition, tumor growth was completely inhibited when mice were treated with MSV/EphA2 in combination with paclitaxel. Furthermore, combination treatment with MSV/EphA2 and docetaxel inhibited growth of HeyA8-MDR tumors, which were otherwise resistant to docetaxel treatment. CONCLUSION: These findings indicate that MSV/EphA2 merits further development as a novel therapeutic agent for ovarian cancer.


Assuntos
Inativação Gênica , Vetores Genéticos/genética , Receptor EphA2/genética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/química , Humanos , Lipossomos , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Silício/química , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
17.
J Drug Deliv ; 2012: 389485, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22506121

RESUMO

Born from the marriage of nanotechnology and medicine, nanomedicine is set to bring advantages in the fight against unmet diseases. The field is recognized as a global challenge, and countless worldwide research and business initiatives are in place to obtain a significant market position. However, nanomedicine belongs to those emerging sectors in which business development methods have not been established yet. Open issues include which type of business model best fits these companies and which strategies would lead them to sustained growth. This paper describes the financial and strategic decisions by nanomedicine start-ups to reach the market successfully, obtain a satisfactory market share, and build and maintain a competitive defendable advantage. Walking nanomedicine-product from the hands of the inventor to those of the doctor, we explored the technological transfer process, which connects laboratories or research institutions to the marketplace. The process involves detailed analysis to evaluate the potentials of end-products, and researches to identify market segment, size, structure, and competitors, to ponder a possible market entry and the market share that managers can realistically achieve at different time horizons. Attracting funds is crucial but challenging. However, investors are starting to visualize the potentials of this field, magnetized by the business of "nano."

18.
J Vis Exp ; (62)2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22546927

RESUMO

The identification of circulating biomarkers holds great potential for non invasive approaches in early diagnosis and prognosis, as well as for the monitoring of therapeutic efficiency.(1-3) The circulating low molecular weight proteome (LMWP) composed of small proteins shed from tissues and cells or peptide fragments derived from the proteolytic degradation of larger proteins, has been associated with the pathological condition in patients and likely reflects the state of disease.(4,5) Despite these potential clinical applications, the use of Mass Spectrometry (MS) to profile the LMWP from biological fluids has proven to be very challenging due to the large dynamic range of protein and peptide concentrations in serum.(6) Without sample pre-treatment, some of the more highly abundant proteins obscure the detection of low-abundance species in serum/plasma. Current proteomic-based approaches, such as two-dimensional polyacrylamide gel-electrophoresis (2D-PAGE) and shotgun proteomics methods are labor-intensive, low throughput and offer limited suitability for clinical applications.(7-9) Therefore, a more effective strategy is needed to isolate LMWP from blood and allow the high throughput screening of clinical samples. Here, we present a fast, efficient and reliable multi-fractionation system based on mesoporous silica chips to specifically target and enrich LMWP.(10,11) Mesoporous silica (MPS) thin films with tunable features at the nanoscale were fabricated using the triblock copolymer template pathway. Using different polymer templates and polymer concentrations in the precursor solution, various pore size distributions, pore structures, connectivity and surface properties were determined and applied for selective recovery of low mass proteins. The selective parsing of the enriched peptides into different subclasses according to their physicochemical properties will enhance the efficiency of recovery and detection of low abundance species. In combination with mass spectrometry and statistic analysis, we demonstrated the correlation between the nanophase characteristics of the mesoporous silica thin films and the specificity and efficacy of low mass proteome harvesting. The results presented herein reveal the potential of the nanotechnology-based technology to provide a powerful alternative to conventional methods for LMWP harvesting from complex biological fluids. Because of the ability to tune the material properties, the capability for low-cost production, the simplicity and rapidity of sample collection, and the greatly reduced sample requirements for analysis, this novel nanotechnology will substantially impact the field of proteomic biomarker research and clinical proteomic assessment.


Assuntos
Biomarcadores/análise , Proteínas Sanguíneas/química , Proteômica/métodos , Dióxido de Silício/química , Proteínas Sanguíneas/isolamento & purificação , Humanos , Peso Molecular , Nanoestruturas/química , Proteômica/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
19.
PLoS One ; 7(9): e45308, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23028922

RESUMO

We compared the growth of human lung cancer cells in an ex vivo three-dimensional (3D) lung model and 2D culture to determine which better mimics lung cancer growth in patients. A549 cells were grown in an ex vivo 3D lung model and in 2D culture for 15 days. We measured the size and formation of tumor nodules and counted the cells after 15 days. We also stained the tissue/cells for Ki-67, and Caspase-3. We measured matrix metalloproteinase (MMP) levels in the conditioned media and in blood plasma from patients with adenocarcinoma of the lung. Organized tumor nodules with intact vascular space formed in the ex vivo 3D lung model but not in 2D culture. Proliferation and apoptosis were greater in the ex vivo 3D lung model compared to the 2D culture. After 15 days, there were significantly more cells in the 2D culture than the 3D model. MMP-1, MMP-9, and MMP-10 production were significantly greater in the ex vivo 3D lung model. There was no production of MMP-9 in the 2D culture. The patient samples contained MMP-1, MMP-2, MMP-9, and MMP-10. The human lung cancer cells grown on ex vivo 3D model form perfusable nodules that grow over time. It also produced MMPs that were not produced in 2D culture but seen in human lung cancer patients. The ex vivo 3D lung model may more closely mimic the biology of human lung cancer development than the 2D culture.


Assuntos
Técnicas de Cultura de Células/métodos , Metaloproteinases da Matriz/metabolismo , Linhagem Celular Tumoral , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Nanoscale ; 3(2): 421-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21135976

RESUMO

Phosphorylated peptides and proteins play an important role in normal cellular activities, e.g., gene expression, mitosis, differentiation, proliferation, and apoptosis, as well as tumor initiation, progression and metastasis. However, technical hurdles hinder the use of common fractionation methods to capture phosphopeptides from complex biological fluids such as human sera. Herein, we present the development of a dual strategy material that offers enhanced capture of low molecular weight phosphoproteins: mesoporous silica thin films with precisely engineered pore sizes that sterically select for molecular size combined with chemically selective surface modifications (i.e. Ga3+, Ti4+ and Zr4+) that target phosphoroproteins. These materials provide high reproducibility (CV=18%) and increase the stability of the captured proteins by excluding degrading enzymes, such as trypsin. The chemical and physical properties of the composite mesoporous thin films were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy and ellipsometry. Using mass spectroscopy and biostatistics analysis, the enrichment efficiency of different metal ions immobilized on mesoporous silica chips was investigated. The novel technology reported provides a platform capable of efficiently profiling the serum proteome for biomarker discovery, forensic sampling, and routine diagnostic applications.


Assuntos
Proteínas/química , Dióxido de Silício/química , Análise por Conglomerados , Íons/química , Metais/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fosfopeptídeos/química , Fosforilação , Porosidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície , Tripsina/metabolismo
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