The Intrinsic Biological Identities of Iron Oxide Nanoparticles and Their Coatings: Unexplored Territory for Combinatorial Therapies

Over the last 20 years, iron oxide nanoparticles (IONPs) have been the subject of increasing investigation due to their potential use as theranostic agents. Their unique physical properties (physical identity), ample possibilities for surface modifications (synthetic identity), and the complex dynamics of their interaction with biological systems (biological identity) make IONPs a unique and fruitful resource for developing magnetic field-based therapeutic and diagnostic approaches to the treatment of diseases such as cancer. Like all nanomaterials, IONPs also interact with different cell types in vivo, a characteristic that ultimately determines their activity over the short and long term. Cells of the mononuclear phagocytic system (macrophages), dendritic cells (DCs), and endothelial cells (ECs) are engaged in the bulk of IONP encounters in the organism, and also determine IONP biodistribution. Therefore, the biological effects that IONPs trigger in these cells (biological identity) are of utmost importance to better understand and refine the efficacy of IONP-based theranostics. In the present review, which is focused on anti-cancer therapy, we discuss recent findings on the biological identities of IONPs, particularly as concerns their interactions with myeloid, endothelial, and tumor cells. Furthermore, we thoroughly discuss current understandings of the basic molecular mechanisms and complex interactions that govern IONP biological identity, and how these traits could be used as a stepping stone for future research.Peer reviewe

Bioactividad intrínseca de nanopartículas magnéticas recubiertas con poli-etilénimina sobre células tumorales pancreáticas y del sistema fagocítico mononuclear

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 12-06-2015La nanotecnología ha significado un considerable salto para aplicaciones biomédicas, debido a las propiedades químico‐ físicas intrínsecas de los biomateriales, y a la posibilidad de modificarlos de acuerdo a los intereses terapéuticos y diagnósticos específicos. Particularmente, las nanopartículas superparamagnéticas de óxido de hierro (SPION) son ampliamente explotadas por sus propiedades magnéticas, no solo en estrategias diagnósticos como agentes de contraste, sino también, como nanotransportadores de drogas. La posibilidad de concentrar estas nanopartículas en el sitio de interés mediante la aplicación de campo magnético externo aporta otra vía para disminuir los efectos secundarios sistémicos de muchas de las actuales drogas anti‐tumorales. Entre las terapias anti-tumorales en las que se han utilizado las nanopartículas está la terapia génica. Para funcionalizar las nanopartículas para transportar ADN/ARN, se han desarrollado diferentes polímeros catiónicos con la capacidad de conjugar ADN y/o ARN, garantizando su estabilidad química y funcional ante las diferentes condiciones fisiológicas (torrente sanguíneo, microambiente tumoral, compartimento endosomal, etc.). Sin embargo, un aspecto importante es la interacción de las propias nanopartículas magnéticas con diferentes sistemas celular como el sistema fagocítico mononuclear, células endoteliales, fibroblastos, y las propias células tumorales, que eventualmente podría definir la eficacia del tratamiento. En este trabajo, estudiamos la interacción de SPION recubiertas con polietilenimina (PEI) desnudas con macrófagos, fibroblastos, células endoteliales, y células tumorales murinas de páncreas. Demostramos que, además de poseer la capacidad de transfectar eficientemente (células HEK293), las SPIONs recubiertas con PEI inhiben la migración e invasión de las células tumorales murinas pancreáticas a través de la disminución de invadosomas y metaloproteinasas, MT1-MMP y MMP2, así como, probablemente, mediante la modulación de la ruta dependiente de microARN-21. Igualmente, estudiamos el efecto biológico que esta nanopartículas tienen sobre células endoteliales y fibroblastos, en los que induce la expresión de genes vinculados con procesos biológicos como la angiogénesis y respuesta inmune, así como inhiben la migración de las células endoteliales. Finalmente, demostramos que las SPIONs activan los macrófagos hacia un fenotipo M1 y modulan la dinámica de formación de podosomas. Además, inhiben la degradación de matriz extracelular por los macrófagos a través de la expresión de inhibidores de metaloproteinasas y la modulación de MMP2. En resumen, estos resultados demuestran que las SPIONs recubiertas con PEI no solo son un agente transfectante, sino también, poseen en sí mismas propiedades anti-metastásica y adyuvantes independientes de la capacidad de transfección, lo que sugiere su uso en estrategias anti-tumorales e inmunoterapéuticasNanotechnology has meant a considerable jump for biomedical applications, due to the intrinsic chemical and physical properties of biomaterials, and the possibility to modify them for specific diagnostic and therapeutic interest. Particularly, the superparamagnetic iron oxide nanoparticles (SPION) are widely exploited for their magnetic properties, not only in diagnostic strategies as contrast agents, but also as drug nanocarriers. The ability to concentrate these nanoparticles at the site of interest by applying external magnetic field provides another way to reduce systemic side effects of current anti-­tumor drugs. Gene therapy is among the anti-­tumor therapies in which the nanoparticles have been used. In this sense, different cationic polymers have been developed with the ability to package DNA and / or RNA, thereby preserving their chemical and functional stability in different physiological conditions (bloodstream, tumor microenvironment, endosomal compartment, etc.). However, an important consideration is the interaction of the magnetic nanoparticles themselves with cellular systems, e.g. the mononuclear phagocyte system, endothelial cells, fibroblasts and the tumor cells themselves, which could eventually influence the efficacy of treatment. In this study, we analyzed the interaction of naked polyethyleneimine (PEI)-­coated SPIONs with macrophages, fibroblasts, endothelial cells, and murine pancreatic tumor cells. We showed that, besides having the ability to efficiently transfect (HEK293 cells), PEI-­coated SPIONs inhibit migration and invasion of murine pancreatic tumor cells by decreasing invadosomas and metalloproteinases MT1-­MMP and MMP2 and, likely by modulating the microRNA-­21-­dependent pathways. Also we studied the biological effects on endothelial cells and fibroblasts, where they induce the expression of genes linked to biological processes, e.g. angiogenesis and immune response, and inhibit migration of endothelial cells. Finally, we showed that PEI-­coated SPIONs activate macrophages (M1 like phenotype) and modulate podosome dynamics. Also, they inhibited the degradation of extracellular matrix by macrophages through the metalloproteinase expression inhibition (MMP2) and induction of metalloproteinase inhibitors. In summary, these results demonstrate that the PEI-­coated SPIONs are not only are able to efficiently transfect cells, but also exert potential anti-­metastatic and adjuvant properties themselves, independently of transfection capacity, suggesting their use in anti-­tumor and immunotherapeutic strategie

PI3K p110δ is expressed by gp38(-)CD31(+) and gp38(+)CD31(+) spleen stromal cells and regulates their CCL19, CCL21, and LTβR mRNA levels.

The role of p110δ PI3K in lymphoid cells has been studied extensively, showing its importance in immune cell differentiation, activation and development. Altered T cell localization in p110δ-deficient mouse spleen suggested a role for p110δ in non-hematopoietic stromal cells, which maintain hematopoietic cell segregation. We tested this hypothesis using p110δ(WT/WT) mouse bone marrow to reconstitute lethally irradiated p110δ(WT/WT) or p110δ(D910A/D910A) (which express catalytically inactive p110δ) recipients, and studied localization, number and percentage of hematopoietic cell subsets in spleen and lymph nodes, in homeostatic conditions and after antigen stimulation. These analyses showed diffuse T cell areas in p110δ(D910A/D910A) and in reconstituted p110δ(D910A/D910A) mice in homeostatic conditions. In these mice, spleen CD4(+) and CD8(+) T cell numbers did not increase in response to antigen, suggesting that a p110δ(D910A/D910A) stroma defect impedes correct T cell response. FACS analysis of spleen stromal cell populations showed a decrease in the percentage of gp38(-)CD31(+) cells in p110δ(D910A/D910A) mice. qRT-PCR studies detected p110δ mRNA expression in p110δ(WT/WT) spleen gp38(-)CD31(+) and gp38(+)CD31(+) subsets, which was reduced in p110δ(D910A/D910A) spleen. Lack of p110δ activity in these cell populations correlated with lower LTβR, CCL19 and CCL21 mRNA levels; these molecules participate in T cell localization to specific spleen areas. Our results could explain the lower T cell numbers and more diffuse T cell areas found in p110δ(D910A/D910A) mouse spleen, as well as the lower T cell expansion after antigen stimulation in p110δ(D910A/D910A) compared with p110δ(WT/WT) mice

Multiphoton imaging of melanoma 3D models with plasmonic nanocapsules

We report the synthesis of plasmonic nanocapsules and the cellular responses they induce in 3D melanoma models for their perspective use as a photothermal therapeutic agent. The wall of the nanocapsules is composed of polyelectrolytes. The inner part is functionalized with discrete gold nanoislands. The cavity of the nanocapsules contains a fluorescent payload to show their ability for loading a cargo. The nanocapsules exhibit simultaneous two-photon luminescent, fluorescent properties and X-ray contrasting ability. The average fluorescence lifetime (τ) of the nanocapsules measured with FLIM (0.3 ns) is maintained regardless of the intracellular environment, thus proving their abilities for bioimaging of models such as 3D spheroids with a complex architecture. Their multimodal imaging properties are exploited for the first time to study tumorspheres cellular responses exposed to the nanocapsules. Specifically, we studied cellular uptake, toxicity, intracellular fate, generation of reactive oxygen species, and effect on the levels of hypoxia by using multi-photon and confocal laser scanning microscopy. Because of the high X-ray attenuation and atomic number of the gold nanostructure, we imaged the nanocapsule-cell interactions without processing the sample. We confirmed maintenance of the nanocapsules’ geometry in the intracellular milieu with no impairment of the cellular ultrastructure. Furthermore, we observed the lack of cellular toxicity and no alteration in oxygen or reactive oxygen species levels. These results in 3D melanoma models contribute to the development of these nanocapsules for their exploitation in future applications as agents for imaging-guided photothermal therapy. Statement of Significance: The novelty of the work is that our plasmonic nanocapsules are multimodal. They are responsive to X-ray and to multiphoton and single-photon excitation. This allowed us to study their interaction with 2D and 3D cellular structures and specifically to obtain information on tumor cell parameters such as hypoxia, reactive oxygen species, and toxicity. These nanocapsules will be further validated as imaging-guided photothermal probe

Semiología ecográfica del tórax patológico en pediatría

Introducción: La ecografía torácica constituye un proceder de gran utilidad para el diagnóstico de múltiples enfermedades en niños. Presenta ventajas que la caracterizan: como ser de fácil aprendizaje y no ser ionizante, algo especialmente importante en la edad pediátrica.Objetivo: Profundizar y actualizar conocimientos sobre los aspectos más importantes de la ecografía torácica en edades pediátricas. Métodos: Se realizó una amplia revisión bibliográfica en las bases de datos médicas (Scielo, Pubmed) de materiales científicos escritos y electrónicos relacionados con el tema, utilizando descriptores de búsqueda: ecografía torácica, semiología ecográfica del tórax normal y patológico en pediatría. Conclusiones: La ecografía torácica es una técnica invaluable, con la ventaja de ser inocua, portable, rápida y de bajo costo. El conocimiento de la semiología ecográfica y una correcta interpretación de los signos radiológicos y de la clínica del paciente permite evitar pruebas innecesarias y dosis de radiación perjudiciales en edades pediátricas, facilitando el diagnóstico precoz y certero de las afecciones respiratorias

Intervención educativa sobre el Virus de Inmunodeficiencia Humana en adolescentes de nivel preuniversitario

Introducción: La infección por el Virus de Inmunodeficiencia Humana, es un problema de salud en el mundo. En Cuba existen avances, se ha eliminado la transmisión prenatal desde el año 2013, aunque no se logra erradicar la epidemia. Objetivo: Implementar una intervención educativa sobre el Virus de Inmunodeficiencia Humana en estudiantes de preuniversitario. Métodos: Se realizó una intervención educativa en el Instituto Preuniversitario Urbano ¨República de Indonesia¨ en Guanajay, Artemisa. El universo fueron 343 estudiantes y de forma aleatoria se seleccionó una muestra de 60. Se aplicó un cuestionario para determinar el conocimiento sobre el agente causal, las vías de transmisión; las conductas de riesgo y las fuentes de información, antes y después de la intervención educativa. El programa educativo se realizó a través de conferencias, talleres y cine debate.  Se utilizó la prueba estadística de Wilconxon para muestras relacionadas. Resultados: Predominó el género femenino en el 66.66 % y el grado de escolaridad onceno en el 58.33 %. Antes de la intervención el 61.33 % no conocían el agente causal, después se revirtió en un 75 %; en relación a las vías de transmisión el 86.66 % no las dominaban, invirtiéndose en el 70 %. Acerca de las medidas de prevención existió desconocimiento en el 88.33 %, modificándose en un 33.33 % y las conductas de riesgo se desconocían el 11.66 %, después se invirtió en un 81.66 %. Conclusiones: El programa de intervención educativa permite elevar los conocimientos sobre el Virus de Inmunodeficiencia Humana en los adolescentes

Educative Intervention about Human Immunodeficiency Virus in adolescents of Senior High School level

Introducción:La infección por el Virus de Inmunodeficiencia Humana, es un problema de salud en el mundo. En Cuba existen avances, se ha eliminado la transmisión prenatal desde el año 2013, aunque no se logra erradicar la epidemia.Objetivo: Implementar una intervención educativa sobre el Virus de Inmunodeficiencia Humana en estudiantes de preuniversitario. Métodos: Se realizó una intervención educativa en el Instituto Preuniversitario Urbano ¨República de Indonesia¨ en Guanajay, Artemisa. El universo fueron 343 estudiantes y de forma aleatoria se seleccionó una muestra de 60. Se aplicó un cuestionario para determinar el conocimiento sobre el agente causal, las vías de transmisión; las conductas de riesgo y las fuentes de información, antes y después de la intervención educativa. El programa educativo se realizó a través de conferencias, talleres y cine debate.  Se utilizó la prueba estadística de Wilconxon para muestras relacionadas. Resultados:Predominó el género femenino en el 66.66 % y el grado de escolaridad onceno en el 58.33 %. Antes de la intervención el 61.33 % no conocían el agente causal, después se revirtió en un 75 %; en relación a las vías de transmisión el 86.66 % no las dominaban, invirtiéndose en el 70 %. Acerca de las medidas de prevención existió desconocimiento en el 88.33 %, modificándose en un 33.33 % y las conductas de riesgo se desconocían el 11.66 %, después se invirtió en un 81.66 %.Conclusiones: El programa de intervención educativa permite elevar los conocimientos sobre el Virus de Inmunodeficiencia Humana en los adolescentes.Introduction:Infection by Human Immunodeficiency Virus, is a health problem worldwide. In Cuba there are advances, prenatal transmission has been eliminated since 2013, although the eradication of the epidemics has not been achieved.Objective: To implement an educative intervention about Human Immunodeficiency Virus in adolescents of Senior High School level. Methods: An educative intervention was carried out at ¨República de Indonesia¨ urban Senior High School in Guanajay, Artemisa. The universe was formed by 343 students and a sample of 60 was selected at random. A questionnaire was applied to determine the knowledge about the causal agent, the ways of transmission; risk behaviors and the sources of information, before and after the educative intervention. The educative syllabus was performed by lectures, workshops and film debates. Wilconxon statistical test was used for related samples. Results:Female gender prevailed in a 66.66 % and eleventh grade in the 58.33 %. Before the intervention, the 61.33 % did not know the causal agent, afterwards, it was inverted in a 75 %; in relation to the ways of transmission, the 86.66 % did not manage them, been reversed in a 70 %. About the ways of prevention, there was no knowledge in the 88.33 %, but it was changed in the 33.33 %, the risk behaviors were unknown in an 11.66 % and after the intervention, there was a 81.66 %.Conclusions: The educative intervention syllabus allows to increase knowledge about Human Immunodeficiency Virus in adolescents

Control of Advanced Cancer: The Road to Chronicity

Despite the recent trend toward a slight decrease in age-adjusted cancer mortality in some countries, crude mortality rates will continue to increase, driven by the demographic shift towards an aged population. Small molecules (small molecules and biologics) are not only a new therapeutic acquisition, but the tools of a more fundamental transition: the transformation of cancer from a rapidly fatal disease into a chronic condition. Antibodies and cancer vaccines can be used for a long time, even beyond progressive disease, and in aged patients, usually unfit for more aggressive conventional treatments. However, this transition to chronicity will require novel developmental guidelines adequate to this kind of drugs, for which optimal dose is not usually the maximal tolerated dose, pharmacokinetics does not define treatment schedule, and tumor shrinkage is not a good correlate of survival. The ongoing cancer immunotherapy program (including several monoclonal antibodies and therapeutic vaccines) at the Centre of Molecular Immunology can illustrate the issues to be addressed, both biological and social, along the path to transform advanced cancer into a chronic non-communicable disease compatible with years of quality life

Unravelling the mechanisms that determine the uptake and metabolism of magnetic single and multicore nanoparticles in a Xenopus laevis model.

Multicore superparamagnetic nanoparticles have been proposed as ideal tools for some biomedical applications because of their high magnetic moment per particle, high specific surface area and long term colloidal stability. Through controlled aggregation and packing of magnetic cores it is possible to obtain not only single-core but also multicore and hollow spheres with internal voids. In this work, we compare toxicological properties of single and multicore nanoparticles. Both types of particles showed moderate in vitro toxicity (MTT assay) tested in Hep G2 (human hepatocellular carcinoma) and Caco-2 (human colorectal adenocarcinoma) cells. The influence of surface chemistry in their biological behavior was also studied after functionalization with O,O′-bis(2-aminoethyl) PEG (2000 Da). For the first time, these nanoparticles were evaluated in a Xenopus laevis model studying their whole organism toxicity and their impact upon iron metabolism. The degree of activation of the metabolic pathway depends on the size and surface charge of the nanoparticles which determine their uptake. The results also highlight the potential of Xenopus laevis model bridging the gap between in vitro cell-based assays and rodent models for toxicity assessment to develop effective nanoparticles for biomedical applications

Iron oxide and iron oxyhydroxide nanoparticles impair SARS-CoV-2 infection of cultured cells

Background Coronaviruses usually cause mild respiratory disease in humans but as seen recently, some human coronaviruses can cause more severe diseases, such as the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the global spread of which has resulted in the ongoing coronavirus pandemic. Results In this study we analyzed the potential of using iron oxide nanoparticles (IONPs) coated with biocompatible molecules like dimercaptosuccinic acid (DMSA), 3-aminopropyl triethoxysilane (APS) or carboxydextran (FeraSpin™ R), as well as iron oxyhydroxide nanoparticles (IOHNPs) coated with sucrose (Venofer®), or iron salts (ferric ammonium citrate -FAC), to treat and/or prevent SARS-CoV-2 infection. At non-cytotoxic doses, IONPs and IOHNPs impaired virus replication and transcription, and the production of infectious viruses in vitro, either when the cells were treated prior to or after infection, although with different efficiencies. Moreover, our data suggest that SARS-CoV-2 infection affects the expression of genes involved in cellular iron metabolism. Furthermore, the treatment of cells with IONPs and IOHNPs affects oxidative stress and iron metabolism to different extents, likely influencing virus replication and production. Interestingly, some of the nanoparticles used in this work have already been approved for their use in humans as anti-anemic treatments, such as the IOHNP Venofer®, and as contrast agents for magnetic resonance imaging in small animals like mice, such as the FeraSpin™ R IONP. Conclusions Therefore, our results suggest that IONPs and IOHNPs may be repurposed to be used as prophylactic or therapeutic treatments in order to combat SARS-CoV-2 infection.This work was supported by the following Grants: CSIC-COV19-012/012202020E154 funded by the Spanish National Research Council Interdisciplinary Thematic Platform (PTI) Global Health (PTI Salud Global), SGL2103021 funded by the European Commission-NextGenerationEU (Regulation EU2020/2094) through CSIC’s Global Health Platform (PTI Salud Global); PDC2021-120759-100 funded by MCIN/AEI/10. 13039/50110 00110 33 and by the “European Union NextGenerationEU/PRTR”, PID2020-112685RB-100 funded by MCIN/AEI/10. 13039/50110 00110 33, and the “Atracción de Talento Investigador” programme (2017-T1/BMD-5155) funded by the “Comunidad de Madrid”. Y. Portilla was first a predoctoral FPU scholar (FPU15/06170) funded by MCIN/AEI/10. 13039/50110 00110 33 and by “ESF Investing in your future”, then a predoctoral scholar funded by CSIC-COV19-012/012202020E154 and is now a postdoctoral scholar funded by the European Commission-NextGenerationEU (Regulation EU2020/2094) through the CSIC’s Global Health Platform (PTI Salud Global, SGL2103021). D. López-García received a JAE-INTRO 2020 Fellowship from the Spanish National Research Council (CSIC, JAEINT-20-01805). V. Mulens-Arias was a postdoctoral scholar working under a Juan de La Cierva-Incorporación Contract (IJCI-2017-31447) funded by MCIN/AEI/10. 13039/50110 00110 33. N. Daviu is a predoctoral scholar (FPU18/04828) funded by MCIN/AEI/10. 13039/50110 00110 33 and by “ESF Investing in your future”. This research work was performed in the framework of the Nanomedicine CSIC HUB (ref. 202180E048).Peer reviewe