RESUMO
Mesenchymal stem cell (MSC) therapy has emerged as a potential therapeutic option for several diseases due to their unique properties of releasing important bioactive factors. Despite the advances in stem cell therapy, it is still difficult to accurately determine the mechanisms of cell activities after in vivo transplantation. The application of noninvasive cell tracking approaches is important to determine tissue distribution and the lifetime of stem cells following their injection, which consequently provides knowledge about the mechanisms of stem cell tissue repair. Superparamagnetic iron oxide nanoparticles (SPION) can provide a very useful tool for labeling and tracking stem cells by magnetic resonance imaging without causing toxic cellular effects and do not elicit any other side effects. Here we describe how to use SPIONs to label mesenchymal stem cells and evaluate efficacy and potential cytotoxicity in vitro.
Assuntos
Rastreamento de Células/métodos , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/citologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/química , Distribuição TecidualRESUMO
BACKGROUND: Nanoparticles in suspension are often utilized for intracellular labeling and evaluation of toxicity in experiments conducted in vitro. The purpose of this study was to undertake a computational modeling analysis of the deposition kinetics of a magnetite nanoparticle agglomerate in cell culture medium. METHODS: Finite difference methods and the Crank-Nicolson algorithm were used to solve the equation of mass transport in order to analyze concentration profiles and dose deposition. Theoretical data were confirmed by experimental magnetic resonance imaging. RESULTS: Different behavior in the dose fraction deposited was found for magnetic nanoparticles up to 50 nm in diameter when compared with magnetic nanoparticles of a larger diameter. Small changes in the dispersion factor cause variations of up to 22% in the dose deposited. The experimental data confirmed the theoretical results. CONCLUSION: These findings are important in planning for nanomaterial absorption, because they provide valuable information for efficient intracellular labeling and control toxicity. This model enables determination of the in vitro transport behavior of specific magnetic nanoparticles, which is also relevant to other models that use cellular components and particle absorption processes.
Assuntos
Nanopartículas de Magnetita/química , Modelos Teóricos , Algoritmos , Simulação por Computador , Convecção , Meios de Cultura/química , Difusão , Cinética , Tamanho da Partícula , Suspensões/químicaRESUMO
En los últimos años ha surgido un gran interés en conocer la biodistribución de las células madre en el organismo después que son infundidas o inyectadas directamente en una parte del cuerpo. Para esto se han usado diferentes procederes, entre ellos, el marcaje de las células con diferentes fluorocromos, tales como la proteína con fluorescencia verde y la proteína con fluorescencia roja; o bien se les hace una transfección con plasmidos que codifican proteínas fluorescentes o se emplean sondas moleculares fluorescentes para la identificación de cromosomas. Recientemente se han introducido técnicas imagenológicas de avanzada no invasivas, entre las que tenemos la resonancia magnético nuclear, así como procederes basados en el marcaje con radionúclidos para la obtención de imágenes detectadas por tomografía por emisión de positrones (PET, del inglés positron emission tomography), o por tomografía computarizada por emisión de fotón único (SPECT, del inglés single- photon emission computed tomography).
In past years there was an increasing interest by to know about the biodistribution of stem cells in organism after its perfusion or direct injection in a part of the body. Thus, we used different procedures including the cell labeling with distinct fluorochromes, such as the green fluorescence protein and the red fluorescence protein or a plasmid transfection codifying the fluorescent proteins of fluorescent molecular stents to identify the chromosomes. Recently non-invasive leading imaging techniques have been introduced including nuclear magnetic resonance. As well as procedures based on radionuclide labeling to obtain the positron emission tomography (PET) images or by photon-emission computed tomography (SPECT).