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1.
Environ Sci Technol ; 57(48): 19612-19623, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37972360

RESUMEN

Land use is a major threat to terrestrial biodiversity. Life cycle assessment is a tool that can assess such threats and thereby support environmental decision-making. Within the Global Guidance for Life Cycle Impact Assessment (GLAM) project, the Life Cycle Initiative hosted by UN Environment aims to create a life cycle impact assessment method across multiple impact categories, including land use impacts on ecosystem quality represented by regional and global species richness. A working group of the GLAM project focused on such land use impacts and developed new characterization factors to combine the strengths of two separate recent advancements in the field: the consideration of land use intensities and land fragmentation. The data sets to parametrize the underlying model are also updated from previous models. The new characterization factors cover five species groups (plants, amphibians, birds, mammals, and reptiles) and five broad land use types (cropland, pasture, plantations, managed forests, and urban land) at three intensity levels (minimal, light, and intense). They are available at the level of terrestrial ecoregions and countries. This paper documents the development of the characterization factors, provides practical guidance for their use, and critically assesses the strengths and remaining shortcomings.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Bosques , Agricultura , Aves , Conservación de los Recursos Naturales , Mamíferos
2.
Lasers Med Sci ; 38(1): 221, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37749444

RESUMEN

Photobiomodulation (PBM) has been proposed as a strategy to improve the regenerative capacity of human adipose-derived stem cells (hASCs). Yet, this effect has been proved in 2D culture conditions. To analyze the effect of different doses of laser irradiation (660 nm) with different levels of energy (1 J, 2 J and 6 J) on hASCs cultured at 2D and 3D conditions. We used gellan gum spongy-like hydrogels as a biomaterial to 3D culture hASCs. Different doses (1-7 daily irradiations) and energy levels (1-6 J) of PBM were applied, and the metabolic activity, viability, proliferation, and release of ROS and IL-8 was evaluated up to 7 days. In 3D, cell proliferation increased at high energy (6 J) and after a single dose of irradiation, while in 2D, metabolic activity and proliferation was enhanced only after 3 doses and independently of the energy. More than 1 dose was needed to promote ROS secretion both in 2D and 3D culture conditions. Interestingly, a decrease of IL-8 secretion was detected only in 3D after 3-7 daily irradiations. Overall, hASCs response to PBM was not only dependent on the energy level and the number of applied stimuli, but also on the in vitro culture conditions.


Asunto(s)
Interleucina-8 , Células Madre Mesenquimatosas , Humanos , Especies Reactivas de Oxígeno , Adipocitos , Vendajes
3.
Annu Rev Biomed Eng ; 21: 145-169, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-30822099

RESUMEN

Chronic skin wounds are the leading cause of nontraumatic foot amputations worldwide and present a significant risk of morbidity and mortality due to the lack of efficient therapies. The intrinsic characteristics of hydrogels allow them to benefit cutaneous healing essentially by supporting a moist environment. This property has long been explored in wound management to aid in autolytic debridement. However, chronic wounds require additional therapeutic features that can be provided by a combination of hydrogels with biochemical mediators or cells, promoting faster and better healing. We survey hydrogel-based approaches with potential to improve the healing of chronic wounds by reviewing their effects as observed in preclinical models. Topics covered include strategies to ablate infection and resolve inflammation, the delivery of bioactive agents to accelerate healing, and tissue engineering approaches for skin regeneration. The article concludes by considering the relevance of treating chronic skin wounds using hydrogel-based strategies.


Asunto(s)
Dermatología/tendencias , Hidrogeles/química , Enfermedades de la Piel/diagnóstico , Cicatrización de Heridas , Animales , Enfermedad Crónica , Células Endoteliales/citología , Humanos , Regeneración , Células de Schwann/citología , Piel/patología , Piel Artificial , Ingeniería de Tejidos/métodos
4.
Biomacromolecules ; 21(7): 2745-2754, 2020 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-32421313

RESUMEN

The use of fucoidan, a marine-origin bioactive polymer, is herein proposed as a component of an innovative and effective strategy against melanoma, one of the most aggressive skin cancers. First, fucoidan antitumor activity, in its soluble form, was assessed presenting increased cytotoxicity over melanoma cells when compared to human dermal fibroblasts and keratinocytes. After this antitumor activity validation and trying to develop a more targeted and local strategy aiming to diminish the cytotoxic effects over noncancer cells, fucoidan was immobilized at the surface of an electrospun nanofiber mesh (NFM_Fu), envisioning the development of a therapeutic patch. The maximum immobilization concentration was 1.2 mg mL-1, determined by the Toluidine Blue Assay and confirmed by XPS. Furthermore, NFM_Fu is more hydrophilic than NFM, presenting a contact angle of 36°, lower than the 121° of the control condition. NFM_Fu was able to reduce human melanoma cell viability by 50% without affecting human dermal fibroblasts and keratinocytes. Taken together, these results set the basis for a valuable approach for melanoma treatment.


Asunto(s)
Melanoma , Nanofibras , Supervivencia Celular , Humanos , Melanoma/tratamiento farmacológico , Polisacáridos/farmacología
5.
Environ Sci Technol ; 54(16): 9715-9728, 2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32667200

RESUMEN

The consumption of materials and products is one of the drivers of biodiversity loss, which in turn affects ecosystem functioning and has socio-economic consequences worldwide. Life cycle assessment (LCA) is a reference methodology for appraising the environmental impacts of products along their value chains. Currently, a generally accepted life cycle impact assessment (LCIA) framework for assessing biodiversity impacts is lacking. The existing LCIA models present weaknesses in terms of the impact drivers considered, geographical coverage, as well as the indicators and metrics adopted. Sound ecological indicators and metrics need to be integrated in order to better assess the impacts of value chains on biodiversity on a global, regional, and local scale. This review analyses studies which, using a life cycle perspective, assess the impacts of products' and services' value chains on biodiversity. We identify and discuss promising synergies between the studies which look beyond the life cycle context, and apply other biodiversity metrics. Our results highlight that the existing metrics of biodiversity impact assessment in LCA are poor at capturing the complexities of biodiversity. There are operational models at the midpoint level that expand on the assessed dimensions of biodiversity (e.g., ecosystem structure), and the drivers of biodiversity loss (e.g., assessment of species exploitation), but efforts are required to fully include these models in the LCA framework. In the business domain, many initiatives are developing frameworks to assess impacts on biodiversity. Many approaches make use of LCIA methods and input-output databases. However, these are generally coupled with other biodiversity metrics. This shows that the current LCA framework is not yet sufficient to support decision-making based on different sets of biodiversity indicators. Ecosystem accounting may provide important ecological information for both the inventory and the impact assessment stages of LCA, helping to disentangle the relationship between biodiversity and ecosystem services. Looking beyond the LCA domain can lead us to new ways of advancing the coverage of biodiversity impacts, in a way that increases the relevance of LCA across a wider range of areas. Future work should assess the indicators provided in various policy contexts.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad
6.
Adv Exp Med Biol ; 1230: 15-25, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32285362

RESUMEN

Microfluidics techniques can be used to process a wide range of biomaterials, from synthetic to natural origin ones. This chapter describes microfluidic processing of biomaterials, mainly polymeric materials of natural origin, focusing on water-soluble polymers that form non-flowing phases after crosslinking. Some polysaccharides and proteins, including agarose, alginate, chitosan, gellan gum, hyaluronic acid, collagen, gelatin, and silk fibroin are emphasized deu to their relevance in the field. The critical characteristics of these materials are discussed, giving particular consideration to those that directly impact its processability using microfluidics. Furthermore, some microfluidic-based processing techniques are presented, describing their suitability to process materials with different sol-gel transition mechanisms.


Asunto(s)
Materiales Biocompatibles , Microfluídica , Biopolímeros , Fibroínas , Hidrogeles
7.
Biol Conserv ; 235: 157-163, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32218608

RESUMEN

Biodiversity is suffering dramatic declines across the globe, threatening the ability of ecosystems to provide the services on which humanity depends. Mainstreaming biodiversity into the plans, strategies and policies of different economic sectors is key to reversing these declines. The importance of this mainstreaming is recognized by the Convention on Biological Diversity (CBD) and its Aichi targets. Individual countries can implement the goals of the CBD through their National Biodiversity Strategies and Action Plans (NBSAPs), which aim to, inter alia, support the mainstreaming of biodiversity into the policies of key economic sectors, such as agriculture, forestry and fisheries. This paper investigates the performance of countries at incorporating biodiversity mainstreaming into their post-2010 NBSAPs. We conduct a large-scale review of 144 NBSAPs against five criteria and calculate a national-level indicator for comparing levels of mainstreaming among countries. Our results show that developing countries, particularly those in Africa, have higher scores, indicating that they have a higher awareness of the importance of biodiversity mainstreaming. Developing nations were also more likely to involve a greater range of stakeholders in the NBSAP development process, whilst developed nations were less likely to give specific details about the monetary contributions of biodiversity to their economies. Overall, our findings suggest that biodiversity mainstreaming remains a challenge across much of the world, but that progress in some areas can provide direction and momentum in the future.

8.
Adv Exp Med Biol ; 1059: 395-420, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29736584

RESUMEN

The cell culture techniques are in the base of any biology-based science. The standard techniques are commonly static platforms as Petri dishes, tissue culture well plates, T-flasks, or well plates designed for spheroids formation. These systems faced a paradigm change from 2D to 3D over the current decade driven by the tissue engineering (TE) field. However, 3D static culture approaches usually suffer from several issues as poor homogenization of the formed tissues and development of a necrotic center which limits the size of in vitro tissues to hundreds of micrometers. Furthermore, for complex tissues as osteochondral (OC), more than recovering a 3D environment, an interface needs to be replicated. Although 3D cell culture is already the reality adopted by a newborn market, a technological revolution on cell culture devices needs a further step from static to dynamic already considering 3D interfaces with dramatic importance for broad fields such as biomedical, TE, and drug development. In this book chapter, we revised the existing approaches for dynamic 3D cell culture, focusing on bioreactors and microfluidic systems, and the future directions and challenges to be faced were discussed. Basic principles, advantages, and challenges of each technology were described. The reported systems for OC 3D TE were focused herein.


Asunto(s)
Reactores Biológicos , Condrogénesis , Microfluídica/métodos , Osteogénesis , Ingeniería de Tejidos/métodos , Animales , Transporte Biológico , Huesos/citología , Comunicación Celular , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Condrocitos/citología , Condrogénesis/fisiología , Diseño de Equipo , Predicción , Humanos , Implantes Experimentales , Dispositivos Laboratorio en un Chip , Osteogénesis/fisiología , Reología
9.
Adv Exp Med Biol ; 1059: 219-240, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29736576

RESUMEN

Stem cell research plays a central role in the future of medicine, which is mainly dependent on the advances on regenerative medicine (RM), specifically in the disciplines of tissue engineering (TE) and cellular therapeutics. All RM strategies depend upon the harnessing, stimulation, or guidance of endogenous developmental or repair processes in which cells have an important role. Among the most clinically challenging disorders, cartilage degeneration, which also affects subchondral bone becoming an osteochondral (OC) defect, is one of the most demanding. Although primary cells have been clinically applied, stem cells are currently seen as the promising tool of RM-related research because of its availability, in vitro proliferation ability, pluri- or multipotency, and immunosuppressive features. Being the OC unit, a transition from the bone to cartilage, mesenchymal stem cells (MSCs) are the main focus for OC regeneration. Promising alternatives, which can also be obtained from the patient or at banks and have great differentiation potential toward a wide range of specific cell types, have been reported. Still, ethical concerns and tumorigenic risk are currently under discussion and assessment. In this book chapter, we revise the existing stem cell-based approaches for engineering bone and cartilage, focusing on cell therapy and TE. Furthermore, 3D OC composites based on cell co-cultures are described. Finally, future directions and challenges still to be faced are critically discussed.


Asunto(s)
Enfermedades Óseas/terapia , Enfermedades de los Cartílagos/terapia , Medicina Regenerativa/métodos , Trasplante de Células Madre/métodos , Células Madre Adultas/trasplante , Trasplante de Médula Ósea , Células Cultivadas/trasplante , Condrocitos/trasplante , Condrogénesis , Células Madre Embrionarias/citología , Predicción , Humanos , Células Madre Pluripotentes Inducidas/trasplante , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Osteogénesis , Medicina Regenerativa/tendencias , Ingeniería de Tejidos/métodos
10.
Mar Drugs ; 16(12)2018 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-30544788

RESUMEN

Collagen is one of the most widely used biomaterials, not only due its biocompatibility, biodegradability and weak antigenic potential, but also due to its role in the structure and function of tissues. Searching for alternative collagen sources, the aim of this study was to extract collagen from the skin of codfish, previously obtained as a by-product of fish industrial plants, and characterize it regarding its use as a biomaterial for biomedical application, according to American Society for Testing and Materials (ASTM) Guidelines. Collagen type I with a high degree of purity was obtained through acid-extraction, as confirmed by colorimetric assays, SDS-PAGE and amino acid composition. Thermal analysis revealed a denaturing temperature around 16 °C. Moreover, collagen showed a concentration-dependent effect in metabolism and on cell adhesion of lung fibroblast MRC-5 cells. In conclusion, this study shows that collagen can be obtained from marine-origin sources, while preserving its bioactivity, supporting its use in biomedical applications.


Asunto(s)
Materiales Biocompatibles/química , Colágeno Tipo I/química , Gadiformes , Piel/química , Animales , Materiales Biocompatibles/aislamiento & purificación , Adhesión Celular/efectos de los fármacos , Línea Celular , Colágeno Tipo I/aislamiento & purificación , Colágeno Tipo I/farmacología , Fibroblastos , Humanos , Extracción Líquido-Líquido , Ensayo de Materiales/métodos
11.
Mar Drugs ; 16(8)2018 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-30081528

RESUMEN

The high prevalence of bone defects has become a worldwide problem. Despite the significant amount of research on the subject, the available therapeutic solutions lack efficiency. Autografts, the most commonly used approaches to treat bone defects, have limitations such as donor site morbidity, pain and lack of donor site. Marine resources emerge as an attractive alternative to extract bioactive compounds for further use in bone tissue-engineering approaches. On one hand they can be isolated from by-products, at low cost, creating value from products that are considered waste for the fish transformation industry. One the other hand, religious constraints will be avoided. We isolated two marine origin materials, collagen from shark skin (Prionace glauca) and calcium phosphates from the teeth of two different shark species (Prionace glauca and Isurus oxyrinchus), and further proposed to mix them to produce 3D composite structures for hard tissue applications. Two crosslinking agents, 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride/N-Hydroxysuccinimide (EDC/NHS) and hexamethylene diisocyanate (HMDI), were tested to enhance the scaffolds' properties, with EDC/NHS resulting in better properties. The characterization of the structures showed that the developed composites could support attachment and proliferation of osteoblast-like cells. A promising scaffold for the engineering of bone tissue is thus proposed, based on a strategy of marine by-products valorisation.


Asunto(s)
Apatitas/química , Colágeno/química , Tiburones , Andamios del Tejido/química , Animales , Apatitas/aislamiento & purificación , Materiales Biocompatibles/química , Materiales Biocompatibles/aislamiento & purificación , Huesos/lesiones , Colágeno/aislamiento & purificación , Reactivos de Enlaces Cruzados/química , Regeneración Tisular Dirigida/métodos , Ensayo de Materiales , Ingeniería de Tejidos/métodos
13.
Environ Manage ; 62(6): 1108-1133, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30128584

RESUMEN

The role of digital technologies for fostering sustainability and efficiency in forest-based supply chains is well acknowledged and motivated several studies in the scope of precision forestry. Sensor technologies can collect relevant data in forest-based supply chains, comprising all activities from within forests and the production of the woody raw material to its transformation into marketable forest-based products. Advanced planning systems can help to support decisions of the various entities in the supply chain, e.g., forest owners, harvest companies, haulage companies, and forest product processing industry. Such tools can help to deal with the complex interdependencies between different entities, often with opposing objectives and actions-which may increase efficiency of forest-based supply chains. This paper analyzes contemporary literature dealing with digital technologies in forest-based supply chains and summarizes the state-of-the-art digital technologies for real-time data collection on forests, product flows, and forest operations, as well as planning systems and other decision support systems in use by supply chain actors. Higher sustainability and efficiency of forest-based supply chains require a seamless information flow to foster integrated planning of the activities over the supply chain-thereby facilitating seamless data exchange between the supply chain entities and foster new forms of collaboration. Therefore, this paper deals with data exchange and multi-entity collaboration aspects in combination with interoperability challenges related with the integration among multiple process data collection tools and advanced planning systems. Finally, this interdisciplinary review leads to the discussion of relevant guidelines that can guide future research and integration projects in this domain.


Asunto(s)
Agricultura Forestal/tendencias , Toma de Decisiones , Agricultura Forestal/métodos , Bosques , Tecnología , Madera/química
14.
Biochim Biophys Acta Bioenerg ; 1858(10): 865-872, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28801050

RESUMEN

Arsenic is a widely distributed environmental toxin whose presence in drinking water poses a threat to >140 million people worldwide. The respiratory enzyme arsenite oxidase from various bacteria catalyses the oxidation of arsenite to arsenate and is being developed as a biosensor for arsenite. The arsenite oxidase from Rhizobium sp. str. NT-26 (a member of the Alphaproteobacteria) is a heterotetramer consisting of a large catalytic subunit (AioA), which contains a molybdenum centre and a 3Fe-4S cluster, and a small subunit (AioB) containing a Rieske 2Fe-2S cluster. Stopped-flow spectroscopy and isothermal titration calorimetry (ITC) have been used to better understand electron transfer through the redox-active centres of the enzyme, which is essential for biosensor development. Results show that oxidation of arsenite at the active site is extremely fast with a rate of >4000s-1 and reduction of the electron acceptor is rate-limiting. An AioB-F108A mutation results in increased activity with the artificial electron acceptor DCPIP and decreased activity with cytochrome c, which in the latter as demonstrated by ITC is not due to an effect on the protein-protein interaction but instead to an effect on electron transfer. These results provide further support that the AioB F108 is important in electron transfer between the Rieske subunit and cytochrome c and its absence in the arsenite oxidases from the Betaproteobacteria may explain the inability of these enzymes to use this electron acceptor.


Asunto(s)
Citocromos c/metabolismo , Transporte de Electrón/fisiología , Oxidorreductasas/metabolismo , Arsenitos/metabolismo , Betaproteobacteria/metabolismo , Catálisis , Dominio Catalítico/fisiología , Electrones , Molibdeno/metabolismo , Oxidación-Reducción , Mapas de Interacción de Proteínas/fisiología , Subunidades de Proteína/metabolismo
15.
Bioscience ; 66(10): 813-828, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28533561

RESUMEN

National ecosystem assessments form an essential knowledge base for safeguarding biodiversity and ecosystem services. We analyze eight European (sub-)national ecosystem assessments (Portugal, United Kingdom, Spain, Norway, Flanders, Netherlands, Finland, and Germany) and compare their objectives, political context, methods, and operationalization. We observed remarkable differences in breadth of the assessment, methods employed, variety of services considered, policy mandates, and funding mechanisms. Biodiversity and ecosystem services are mainly assessed independently, with biodiversity conceptualized as underpinning services, as a source of conflict with services, or as a service in itself. Recommendations derived from our analysis for future ecosystem assessments include the needs to improve the common evidence base, to advance the mapping of services, to consider international flows of services, and to connect more strongly to policy questions. Although the context specificity of national ecosystem assessments is acknowledged as important, a greater harmonization across assessments could help to better inform common European policies and future pan-regional assessments.

16.
Lab Invest ; 94(6): 663-73, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24709778

RESUMEN

Addressing the problem of vascularization is of vital importance when engineering three-dimensional (3D) tissues. Endothelial cells are increasingly used in tissue-engineered constructs to obtain prevascularization and to enhance in vivo neovascularization. Rat bone marrow stromal cells were cultured in thermoresponsive dishes under osteogenic conditions with human umbilical vein endothelial cells (HUVECs) to obtain homotypic or heterotypic cell sheets (CSs). Cells were retrieved as sheets from the dishes after incubation at 20 °C. Monoculture osteogenic CSs were stacked on top of homotypic or heterotypic CSs, and subcutaneously implanted in the dorsal flap of nude mice for 7 days. The implants showed mineralized tissue formation under both conditions. Transplanted osteogenic cells were found at the new tissue site, demonstrating CS bone-inductive effect. Perfused vessels, positive for human CD31, confirmed the contribution of HUVECs for the neovascularization of coculture CS constructs. Furthermore, calcium quantification and expression of osteocalcin and osterix genes were higher for the CS constructs, with HUVECs demonstrating the more robust osteogenic potential of these constructs. This work demonstrates the potential of using endothelial cells, combined with osteogenic CSs, to increase the in vivo vascularization of CS-based 3D constructs for bone tissue engineering purposes.


Asunto(s)
Técnicas de Cocultivo/métodos , Células Endoteliales/citología , Osteoblastos/citología , Osteogénesis/fisiología , Ingeniería de Tejidos/métodos , Animales , Células de la Médula Ósea , Trasplante de Células , Femenino , Células Endoteliales de la Vena Umbilical Humana , Masculino , Células Madre Mesenquimatosas , Ratones , Ratones Desnudos , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo
17.
Biomacromolecules ; 15(8): 2849-60, 2014 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-24963559

RESUMEN

Recent achievements in the area of tissue engineering (TE) have enabled the development of three-dimensional (3D) cell-laden hydrogels as in vitro platforms that closely mimic the 3D scenario found in native tissues. These platforms are extensively used to evaluate cellular behavior, cell-cell interactions, and tissue-like formation in highly defined settings. In this study, we propose a scalable and flexible 3D system based on microsized hydrogel fibers that might be used as building blocks for the establishment of 3D hydrogel constructs for vascularized bone TE applications. For this purpose, chitosan (CHT) coated κ-carrageenan (κ-CA) microfibers were developed using a two-step procedure involving ionotropic gelation (for the fiber formation) of κ-CA and its polyelectrolyte complexation with CHT (for the enhancement of fiber stability). The performance of the obtained fibers was assessed regarding their swelling and stability profiles, as well as their ability to carry and, subsequently, promote the outward release of microvascular-like endothelial cells (ECs), without compromising their viability and phenotype. Finally, the possibility of assembling and integrating these cell-laden fibers within a 3D hydrogel matrix containing osteoblast-like cells was evaluated. Overall, the obtained results demonstrate the suitability of the microsized κ-CA fibers to carry and deliver phenotypically apt microvascular-like ECs. Furthermore, it is shown that it is possible to assemble these cell-laden microsized fibers into 3D heterotypic hydrogels constructs. This in vitro 3D platform provides a versatile approach to investigate the interactions between multiple cell types in controlled settings, which may open up novel 3D in vitro culture techniques to better mimic the complexity of tissues.


Asunto(s)
Sustitutos de Huesos/química , Carragenina/química , Células Endoteliales/metabolismo , Hidrogeles/química , Ingeniería de Tejidos , Andamios del Tejido/química , Comunicación Celular , Células Cultivadas , Células Endoteliales/citología , Humanos
18.
Acta Biomater ; 178: 93-110, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38382833

RESUMEN

While 3D tumor models have greatly evolved over the past years, there is still a strong requirement for more biosimilar models which are capable of recapitulating cellular crosstalk within the tumor microenvironment while equally displaying representative levels of tumor aggressiveness and invasion. Herein, we disclose an assembloid melanoma model based on the fusion of individual stromal multicellular spheroids (MCSs). In contrast to more traditional tumor models, we show that it is possible to develop self-organizing, heterotypic melanoma models where tumor cells present stem-cell like features like up-regulated pluripotency master regulators SOX2, POU5F1 and NANOG. Additionally, these assembloids display high levels of invasiveness while embedded in 3D matrices as evidenced by stromal cell promotion of melanoma cell invasion via metalloproteinase production. Furthermore, sensitivity to anticancer drug doxorubicin was demonstrated for the melanoma assembloid model. These findings suggest that melanoma assembloids may play a significant role in the field of 3D cancer models as they more closely mimic the tumor microenvironment when compared to more traditional MCSs, opening the doors to a better understanding of the role of tumor microenvironment in supporting tumor progression. STATEMENT OF SIGNIFICANCE: The development of complex 3D tumor models that better recapitulate the tumor microenvironment is crucial for both an improved comprehension of intercellular crosstalk and for more efficient drug screening. We have herein developed a self-organizing heterotypic assembloid-based melanoma model capable of closely mimicking the tumor microenvironment. Key features recapitulated were the preservation of cancer cell stemness, sensitivity to anti-cancer agents and tumor cell invasion promoted by stromal cells. The approach of pre-establishing distinct stromal domains for subsequent combination into more complex tumor constructs provides a route for developing superior tumor models with a higher degree of similarity to native cancer tissues.


Asunto(s)
Melanoma , Humanos , Esferoides Celulares , Microambiente Tumoral , Células del Estroma , Línea Celular Tumoral
19.
Bioact Mater ; 37: 253-268, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38585489

RESUMEN

The chronic shortage of organs and tissues for transplantation represents a dramatic burden on healthcare systems worldwide. Tissue engineering offers a potential solution to address these shortages, but several challenges remain, with prevascularization being a critical factor for in vivo survival and integration of tissue engineering products. Concurrently, a different challenge hindering the clinical implementation of such products, regards their efficient preservation from the fabrication site to the bedside. Hypothermia has emerged as a potential solution for this issue due to its milder effects on biologic systems in comparison with other cold preservation methodologies. Its impact on prevascularization, however, has not been well studied. In this work, 3D prevascularized constructs were fabricated using adipose-derived stromal vascular fraction cells and preserved at 4 °C using Hypothermosol or basal culture media (α-MEM). Hypothermosol efficiently preserved the structural and cellular integrity of prevascular networks as compared to constructs before preservation. In contrast, the use of α-MEM led to a clear reduction in prevascular structures, with concurrent induction of high levels of apoptosis and autophagy at the cellular level. In vivo evaluation using a chorioallantoic membrane model demonstrated that, in opposition to α-MEM, Hypothermosol preservation retained the angiogenic potential of constructs before preservation by recruiting a similar number of blood vessels from the host and presenting similar integration with host tissue. These results emphasize the need of studying the impact of preservation techniques on key properties of tissue engineering constructs such as prevascularization, in order to validate and streamline their clinical application.

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