RESUMO
BACKGROUND: Cell-derived sheets are of global interest for regenerative therapy. Transplanting a sheet for abdominal organs requires a device for laparoscopic delivery to minimize invasiveness. Here, using a porcine model, we aimed to confirm the feasibility of a device developed to deliver sheets to the thoracic cavity in a laparoscopic transplantation procedure. MATERIAL AND METHODS: We used the device to transplant human skeletal myoblast cell sheets onto the liver and measured extra-corporeal, intra-abdominal, and total procedure times for sheet transplantation. Tissues, including the liver and the sheet, were collected two days after transplantation and analyzed histologically. RESULTS: In all experiments (n = 27), all sheets were successfully placed at target locations. The mean (± standard deviation) extra-corporeal, intra-abdominal, and total procedure times were 44 ± 29, 33 ± 12, and 77 ± 36 s, respectively. We found no difference between the two surgeons in procedure times. Histological analyses showed no liver damage with the transplantation and that sheets were transplanted closely onto the liver tissue without gaps. CONCLUSION: We confirmed the feasibility of a simple universal device to transplant cell-derived sheets via laparoscopic surgery. This device could support a minimally invasive procedure for sheet transplantation.
Assuntos
Laparoscopia , Fígado , Animais , Laparoscopia/métodos , Suínos , Fígado/cirurgia , Humanos , Estudos de Viabilidade , Mioblastos Esqueléticos/transplante , Modelos Animais , Duração da Cirurgia , Transplante de Células/métodos , Transplante de Células/instrumentaçãoRESUMO
The transplantation of various immune cell types are promising approaches for the treatment of ischemic cardiovascular disease including myocardial infarction (MI) and peripheral arterial disease (PAD). Major limitation of these so-called Advanced Therapy Medicinal Products (ATMPs) is the ischemic microenvironment affecting cell homeostasis and limiting the demanded effect of the transplanted cell products. Accordingly, different clinical and experimental strategies have been evolved to overcome these obstacles. Here, we give a short review of the different experimental and clinical strategies to solve these issues due to ischemic cardiovascular disease.
Assuntos
Transplante de Células/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Hematopoéticas/metabolismo , Isquemia/terapia , Infarto do Miocárdio/terapia , Neovascularização Fisiológica/efeitos dos fármacos , Doença Arterial Periférica/terapia , Animais , Doenças Cardiovasculares/terapia , Hipóxia Celular/fisiologia , Transplante de Células/instrumentação , Terapia Baseada em Transplante de Células e Tecidos/instrumentação , Microambiente Celular/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/imunologia , Neovascularização Fisiológica/imunologia , Doença Arterial Periférica/imunologiaRESUMO
OBJECTIVES: To investigate the therapy of stress urinary incontinence in a preclinical setting cells were injected into the urethrae of minipigs; however, cells injected by William's needle were frequently misplaced or lost; thus, we investigated if needle-free cell injections using a novel waterjet technology facilitates precise injections in the urethral sphincter complex. MATERIALS AND METHODS: Porcine adipose tissue-derived stromal cells (pADSCs) were isolated from boars, expanded, labelled, and injected in the sphincter of female pigs by waterjet employing two different protocols. After incubation for 15 min or 3 days, the urethrae of the pigs were examined. Injected cells were visualised by imaging and fluorescence microscopy of tissue sections. DNA of injected male cells was verified by polymerase chain reaction (PCR) of the sex-determining region (SRY) gene. Cell injections by William's needle served as controls. RESULTS: The new waterjet technology delivered pADSCs faster and with better on-site precision than the needle injections. Bleeding during or after waterjet injection or other adverse effects, such as swelling or urinary retention, were not observed. Morphologically intact pADSCs were detected in the urethrae of all pigs treated by waterjet. SRY-PCR of chromosomal DNA and detection of recombinant green fluorescent protein verified the injection of viable cells. In contrast, three of four pigs injected by William's needle displayed no or misplaced cells. CONCLUSION: Transurethral injection of viable pADSCs by waterjet is a simple, fast, precise, and yet gentle new technology. This is the first proof-of-principle concept study providing evidence that a waterjet injects intact cells exactly in the tissue targeted in a preclinical in vivo situation. To further explore the clinical potential of the waterjet technology longer follow-up, as well as incontinence models have to be studied.
Assuntos
Transplante de Células/métodos , Injeções/métodos , Células Estromais/transplante , Uretra , Incontinência Urinária por Estresse/cirurgia , Tecido Adiposo/citologia , Animais , Transplante de Células/instrumentação , Feminino , Injeções/instrumentação , Suínos , Porco Miniatura , Fatores de TempoRESUMO
The long-term function of transplanted therapeutic cells typically requires systemic immune suppression. Here, we show that a retrievable implant comprising a silicone reservoir and a porous polymeric membrane protects human cells encapsulated in it after implant transplantation in the intraperitoneal space of immunocompetent mice. Membranes with pores 1 µm in diameter allowed host macrophages to migrate into the device without the loss of transplanted cells, whereas membranes with pore sizes <0.8 µm prevented their infiltration by immune cells. A synthetic polymer coating prevented fibrosis and was necessary for the long-term function of the device. For >130 days, the device supported human cells engineered to secrete erythropoietin in immunocompetent mice, as well as transgenic human cells carrying an inducible gene circuit for the on-demand secretion of erythropoietin. Pancreatic islets from rats encapsulated in the device and implanted in diabetic mice restored normoglycaemia in the mice for over 75 days. The biocompatible device provides a retrievable solution for the transplantation of engineered cells in the absence of immunosuppression.
Assuntos
Transplante de Células/métodos , Sobrevivência de Enxerto , Próteses e Implantes , Animais , Cápsulas , Transplante de Células/instrumentação , Materiais Revestidos Biocompatíveis , Diabetes Mellitus Experimental/terapia , Desenho de Equipamento , Eritropoetina/genética , Eritropoetina/metabolismo , Reação a Corpo Estranho/prevenção & controle , Células HEK293 , Humanos , Ilhotas Pancreáticas , Transplante das Ilhotas Pancreáticas/instrumentação , Transplante das Ilhotas Pancreáticas/métodos , Camundongos , Permeabilidade , Ratos , Transplante HeterólogoRESUMO
Cell-based immunotherapy for cancer is emerging as an attractive alternative to conventional small-molecule or antibody-based treatment. Due to the characteristics of cell-based therapy, validation of test materials before in vivo administration is required. Here we describe general validation steps for preclinical evaluation of cell-based immunotherapy. We also describe a xenograft model of human colorectal cancer. This model can be used for applied to preclinical evaluation of various cell-based therapy regimens for colorectal cancer treatment.
Assuntos
Transplante de Células/métodos , Neoplasias Colorretais/terapia , Imunoterapia/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Sobrevivência Celular , Transplante de Células/instrumentação , Neoplasias Colorretais/imunologia , Células Dendríticas/imunologia , Células Dendríticas/transplante , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Humanos , Imunoterapia/instrumentação , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/transplante , Camundongos , Camundongos Nus , Camundongos SCID , Linfócitos T/imunologia , Linfócitos T/transplante , Estudos de Validação como Assunto , Ensaios Antitumorais Modelo de Xenoenxerto/instrumentaçãoRESUMO
A capsule-type microrobot exhibits "pick-and-drop" (P&D) motion to hold a particle within a confined volume and transports it via a corkscrewing motion. The P&D motion is possible because the capsule-type microrobot has two parts: a plunger and a cap. The fabricated microrobots are wirelessly controlled by a magnetic manipulator. Drugs or cells can be encapsulated in the container of the capsule-type microrobot by the P&D motion or attached to the surface of the cap, which can be used as a supporting structure. Therefore, the capsule-type microrobot can deliver suspended or adherent cells. The drug or cells are minimally exposed or not completely exposed to the surrounding fluid and do not experience shear force when encapsulated in the container. As a proof-of-concept, secure transportation of microparticles in the confined volume of the capsule via P&D motion is demonstrated. In addition, the cap is used as a scaffold for neuronal cell culture on a rat brain slice to demonstrate its biocompatibility and feasibility for targeted cell delivery. The proposed capsule-type microrobot is suitable for diverse applications, as it protects the encapsulated materials.
Assuntos
Transplante de Células , Sistemas de Liberação de Medicamentos , Robótica , Animais , Cápsulas , Transplante de Células/instrumentação , Transplante de Células/métodos , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Masculino , Ratos , Ratos Sprague-Dawley , Robótica/instrumentação , Robótica/métodosRESUMO
Thermosensitive hydrogels have been studied for potential application as promising alternative cell carriers in cell-based regenerative therapies. In this study, a thermosensitive butane diisocyanate (BDI)-collagen hydrogel (BC hydrogel) was designed as an injectable cell delivery carrier of tendon stem/progenitor cells (TSPCs) for tendon tissue engineering. We functionalized the BDI hydrogel with the addition of 20% (v/v) collagen I gel to obtain the thermosensitive BC hydrogel, which was then seeded with TSPCs derived from human Achilles tendons. The BC hydrogel compatibility and TSPC behavior and molecular response to the 3D hydrogel were investigated. Collagen (COL) I gel served as a control group. Our findings demonstrated that the BC hydrogel was thermosensitive, and hardened above 25 °C. It supported TSPC survival, proliferation, and metabolic activity with satisfactory dimension stability and biocompatibility, as revealed by gel contraction assay, live/dead staining, DNA quantification, and resazurin metabolic assay. Phalloidin-based visualization of F-actin demonstrated that the TSPCs were stretched within COL I gel with classical spindle cell shapes; similar cell morphologies were also found in the BC hydrogel. The gene expression profile of TSPCs in the BC hydrogel was comparable with that in COL I gel. Moreover, the BC hydrogel supported capillary-like structure formation by human umbilical vein endothelial cells (HUVECs) in the hydrogel matrix. Taken together, these results suggest that the thermosensitive BC hydrogel holds great potential as an injectable cell delivery carrier of TSPCs for tendon tissue engineering.
Assuntos
Materiais Biocompatíveis/química , Transplante de Células/instrumentação , Hidrogéis/química , Células-Tronco/citologia , Tendões/citologia , Tendões/cirurgia , Engenharia Tecidual/métodos , Tendão do Calcâneo/metabolismo , Tendão do Calcâneo/patologia , Actinas/química , Apoptose , Sítios de Ligação , Proliferação de Células , Sobrevivência Celular , Transplante de Células/métodos , Colágeno/química , Perfilação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Permeabilidade , Temperatura , Alicerces TeciduaisRESUMO
Microspheres have long been used in drug delivery applications because of their controlled release capabilities. They have increasingly served as the fundamental building block for fabricating scaffolds for regenerative engineering because of their ability to provide a porous network, offer high-resolution control over spatial organization, and deliver growth factors/drugs and/or nanophase materials. Because they provide physicochemical gradients via spatiotemporal release of bioactive factors and nanophase ceramics, microspheres are a desirable tool for engineering complex tissues and biological interfaces. In this review we describe various methods for microsphere fabrication and sintering, and elucidate how these methods influence both micro- and macroscopic scaffold properties, with a special focus on the nature of sintering. Furthermore, we review key applications of microsphere-based scaffolds in regenerating various tissues. We hope to inspire researchers to join a growing community of investigators using microspheres as tissue engineering scaffolds so that their full potential in regenerative engineering may be realized.
Assuntos
Materiais Biocompatíveis/síntese química , Transplante de Células/instrumentação , Regeneração Tecidual Guiada/instrumentação , Microesferas , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Animais , Desenho de Equipamento , HumanosRESUMO
BACKGROUND: The clinical application of cells and the development of new delivery systems have allowed significant advances in the field of cell therapy and encapsulation in recent years. The ability to combine cells and biocompatible matrices in the encapsulation of cells providing long-term delivery has provides new therapeutic alternatives in the development of new therapies. METHODS: A structured search of bibliographic databases was carried out to determine the entire methodology related to cell encapsulation with clinical application. RESULTS: Cell encapsulation provides increased retention time in the target tissue improving its therapeutic efficacy. This technology involves the development of a physical barrier (natural or synthetic matrix surrounded by a semipermeable membrane) to isolate and protect cells from the host's immune system maintaining the microenvironment of embedded cells, their viability and their capacity of differentiation, improving their function in vivo, and reducing side effects associated with the use of immunosuppressive therapy. CONCLUSION: The purpose of this review is to discuss the different technologies of cell encapsulation and the different materials utilized from both, natural and synthetic origin, and provide an overview of current therapeutic applications of cell encapsulation, as well as, the perspectives for their clinical application including as a novelty the current application in clinical trials.
Assuntos
Materiais Biocompatíveis/química , Tecnologia Biomédica/métodos , Transplante de Células/métodos , Animais , Tecnologia Biomédica/instrumentação , Diferenciação Celular/fisiologia , Transplante de Células/instrumentação , Células Imobilizadas , Ensaios Clínicos como Assunto , HumanosRESUMO
These days, cell delivery is considered a potential method for treatment of many genetic diseases or tissue regeneration applications. In conventional cell delivery methods, cells are encapsulated in or cultured on biocompatible polymers. However, the main problem with these carriers is their lack of targeting ability. For tissue regeneration or many cell treatments, it is needed to deliver cells to a specific site of action. Magnetic microrobots based on industrial photoresists have been studied in literature for magnetically controllable carriers. However, there are some issues about biodegradation and removal of these microrobots from the body. In this paper, we hypothesis fabrication of new generation of biodegradable magnetic microrobots based on additive manufacturing methods to overcome this problem and to bring this evolving field to a new level.
Assuntos
Implantes Absorvíveis , Transplante de Células/instrumentação , Separação Imunomagnética/instrumentação , Robótica/instrumentação , Alicerces Teciduais , Desenho de Equipamento , MiniaturizaçãoRESUMO
New and improved oncological therapies are now able to cure more than 80% of cancer-affected children in Europe. However, such treatments are gonadotoxic and result in fertility issues, especially in boys who are not able to provide a sperm sample before starting chemo/radiotherapy because of their prepubertal state. For these boys, cryopreservation of immature testicular tissue (ITT) is the only available option, aiming to preserve spermatogonial stem cells (SSCs). Both slow-freezing and vitrification have been investigated to this end and are now applied in a clinical setting for SSC cryopreservation. Research now has to focus on methods that will allow fertility restoration. This review discusses different studies that have been conducted on ITT transplantation, including those using growth factor supplementation like free molecules, or tissue encapsulation with or without nanoparticles, as well as the possibility of developing a bioartificial testis that can be used for in vitro gamete production or in vivo transplantation.
Assuntos
Transplante de Células/métodos , Células Imobilizadas/transplante , Criopreservação , Hidrogéis/uso terapêutico , Infertilidade Masculina/prevenção & controle , Nanotecnologia/métodos , Espermatogônias/transplante , Alicerces Teciduais , Animais , Transplante de Células/instrumentação , Humanos , Masculino , PuberdadeRESUMO
Purpose: To develop a clinically applicable transplantation device and surgical procedure for extracellular matrix-scaffold-supported human-induced pluripotent stem cell-derived retinal pigment epithelium (hiPSC-RPE) cell sheet transplantation for clinical use. Methods: The developed surgical device consisted of a custom-designed hand piece and a cannula. The subretinal transplantation of hiPSC-RPE cell sheets was performed in 12 rabbits. The results evaluated were the graft condition (damage or fold), side (front or back), position (center, near, far), and direction (anterior, posterior, right, left) immediately after surgery and the graft condition (shrinking or fold) 2 weeks after surgery. These results were evaluated by fundus photography and optical coherence tomography, followed by immersion-fixed histology. Results: All grafts could be transplanted without obvious damage. The transplanted grafts included 2 of 12 folded grafts, 12 of 12 front side, 12 of 12 center position, 10 of 12 anterior direction, and 2 of 12 right direction immediately after surgery, whereas transplantation with a distance between an inlet and an outlet greater than graft and the coaxial direction of the flow paths and the insertion device posed the correct condition and direction. Two weeks after the surgery, the transplanted grafts included two folded grafts and four shrunken grafts; however, complete drainage of subretinal fluid for adhesion between the graft and the host prevented shrunken grafts. Conclusions: A developed surgical device and procedure allow grafts to be transplanted into the targeted transplantation site safely and reproducibly. This surgical method will provide additional information on the advancement of future RPE transplantation therapies.
Assuntos
Transplante de Células/instrumentação , Matriz Extracelular , Degeneração Macular/cirurgia , Doenças Retinianas/cirurgia , Epitélio Pigmentado da Retina/citologia , Alicerces Teciduais , Animais , Linhagem Celular , Modelos Animais de Doenças , Desenho de Equipamento , Humanos , Células-Tronco Pluripotentes Induzidas , Degeneração Macular/patologia , Coelhos , Doenças Retinianas/diagnóstico , Epitélio Pigmentado da Retina/transplante , Tomografia de Coerência Óptica , Transplante AutólogoRESUMO
Technical issues of experimental hepatocyte transplantation in pigs, i.e., selection of animals, anesthesia, route of transplantation, and segment-specific transplantation have described.
Assuntos
Transplante de Células/métodos , Hepatócitos/transplante , Fígado/cirurgia , Porco Miniatura/fisiologia , Animais , Animais Geneticamente Modificados , Transplante de Células/efeitos adversos , Transplante de Células/instrumentação , Feminino , Fígado/anatomia & histologia , Masculino , Modelos Animais , Veia Porta/cirurgia , Cuidados Pós-Operatórios/métodos , Suínos , Coleta de Tecidos e Órgãos/instrumentação , Coleta de Tecidos e Órgãos/métodos , Veias Umbilicais/cirurgiaRESUMO
Wilson's disease (WD) is characterized by the inability to excrete copper (Cu) from the body with progressive tissue injury, especially in liver and brain. The molecular defect in WD concerns mutations in ATP7B gene leading to loss of Cu transport from the hepatocyte to the bile canaliculus. While drugs, e.g., Cu chelators, have been available for several decades, these must be taken lifelong, which can be difficult due to issues of compliance or side effects. Many individuals may require liver transplantation, which can also be difficult due to donor organ shortages. Therefore, achieving permanent cures via cell or gene therapy are of great interest for WD. Cell therapy is feasible because transplanted hepatocytes can integrate in liver parenchyma and restore deficient functions, including transport of Cu into bile. The availability of authentic animal models that recapitulate hepatic WD, especially the Long-Evans Cinnamon (LEC) rat, has advanced cell transplantation research in WD. We describe requirements for cell therapy in animal models with several standardized methods for studies to test or refine cell therapy strategies in WD.
Assuntos
Transplante de Células/métodos , Modelos Animais de Doenças , Hepatócitos/transplante , Degeneração Hepatolenticular/terapia , Ratos Endogâmicos LEC/fisiologia , Animais , Transplante de Células/efeitos adversos , Transplante de Células/instrumentação , Cobre/metabolismo , ATPases Transportadoras de Cobre/genética , Terapia Genética/métodos , Eliminação Hepatobiliar , Degeneração Hepatolenticular/genética , Degeneração Hepatolenticular/patologia , Humanos , Fígado/citologia , Fígado/patologia , Fígado/cirurgia , Transplante de Fígado/efeitos adversos , Mutação , Ratos , Ratos Endogâmicos LEC/cirurgiaRESUMO
Hepatocyte transplantation is the best approach to maintain and propagate differentiated hepatocytes from different species. Host liver has to be adapted for transplanted hepatocytes productive engraftment and proliferation being required a chronic liver injury to eliminate host hepatocytes and provide a proliferative advantage to the transplanted hepatocytes. Most valuable mouse models for xenograft hepatocyte transplantation are based on genetically modified animals to cause a chronic liver damage and to limit host hepatocyte regeneration potential. We present a methodology that generates a chronic liver damage and can be applied to any host mouse strain and animal species based on the inoculation of a recombinant adenovirus to express herpes simplex thymidine kinase in host hepatocytes sensitizing them to ganciclovir treatment. This causes a prolonged liver damage that allows hepatocyte transplantation and generation of regenerative nodules in recipient mouse liver integrated by transplanted cells and host sinusoidal. Obtained chimeric animals maintain functional chimeric nodules for several weeks, ready to be used in any study.
Assuntos
Adenoviridae/genética , Transplante de Células/métodos , Hepatócitos/transplante , Regeneração Hepática/efeitos dos fármacos , Fígado/fisiologia , Condicionamento Pré-Transplante/métodos , Animais , Separação Celular/métodos , Transplante de Células/efeitos adversos , Transplante de Células/instrumentação , Doença Hepática Crônica Induzida por Substâncias e Drogas , Modelos Animais de Doenças , Ganciclovir/toxicidade , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Simplexvirus/genética , Timidina Quinase/genética , Transdução Genética/métodos , Quimeras de Transplante/fisiologia , Quimeras de Transplante/cirurgia , Transplante Heterólogo/efeitos adversos , Transplante Heterólogo/métodos , Proteínas não Estruturais Virais/genéticaRESUMO
In the context of cell transplantation in the liver parenchyma, preconditioning is essential to enhance cell engraftment and liver repopulation. The authors have developed a minimally invasive technique of temporary portal embolization using an absorbable material, called reversible portal vein embolization. We hereby describe the method for isolating hepatocytes from a donor rat before transplanting hepatocytes after reversible portal vein embolization in the recipient.
Assuntos
Transplante de Células/métodos , Hepatócitos/transplante , Regeneração Hepática , Fígado/fisiologia , Veia Porta/cirurgia , Condicionamento Pré-Transplante/métodos , Animais , Separação Celular/instrumentação , Separação Celular/métodos , Transplante de Células/instrumentação , Gelatina/administração & dosagem , Fígado/irrigação sanguínea , Fígado/citologia , Fígado/cirurgia , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Perfusão/instrumentação , Perfusão/métodos , Ratos , Baço/cirurgiaRESUMO
Alginate encapsulation of cells is an attractive technique in which alginate becomes polymerized entrapping the cells. The structure of formed microbeads/microcapsules is semipermeable as it allows oxygen and nutrients to go in, and waste products and other materials produced by the cells to go out. Here, we describe basic protocols for alginate encapsulation of human hepatocytes and methods for assessing the microbeads produced.
Assuntos
Alginatos/química , Transplante de Células/métodos , Composição de Medicamentos/métodos , Hepatócitos/transplante , Cápsulas/química , Técnicas de Cultura de Células , Separação Celular/métodos , Sobrevivência Celular , Transplante de Células/instrumentação , Colorimetria/métodos , Composição de Medicamentos/instrumentação , Ensaio de Imunoadsorção Enzimática/métodos , Ácido Glucurônico/química , Hepatócitos/fisiologia , Ácidos Hexurônicos/química , Humanos , Fígado/citologia , Fígado/cirurgia , Microscopia , MicroesferasRESUMO
The liver has an important function in the human body and plays a crucial role in its metabolism. Orthotopic liver transplantation (OLT) is the gold standard treatment for patients presenting liver failure or end stage liver diseases, and is also applied for liver based intractable metabolic disorders. Due to organ shortage, invasive surgery and persistent mortality/morbidity, other treatments have to be explored. Amongst these, hepatocyte transplantation is an attractive alternative and has shown promising results in the treatment of miscellaneous metabolic disorders.
Assuntos
Separação Celular/métodos , Transplante de Células/métodos , Criopreservação/métodos , Hepatócitos/transplante , Fígado/cirurgia , Doenças Metabólicas/cirurgia , Diferenciação Celular , Separação Celular/instrumentação , Sobrevivência Celular , Transplante de Células/instrumentação , Criança , Criopreservação/instrumentação , Seleção do Doador/métodos , Seleção do Doador/normas , Doença Hepática Terminal/cirurgia , Rejeição de Enxerto/prevenção & controle , Hepatócitos/fisiologia , Humanos , Terapia de Imunossupressão/métodos , Fígado/citologia , Fígado/metabolismo , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Cultura Primária de Células/métodos , Coleta de Tecidos e Órgãos/métodosAssuntos
Melanócitos/transplante , Punções , Vitiligo/cirurgia , Transplante de Células/instrumentação , Transplante de Células/métodos , Derme/ultraestrutura , Epiderme/ultraestrutura , Genes Reporter , Humanos , Técnicas In Vitro , Lasers de Gás , Lasers de Estado Sólido , Agulhas , Técnicas de Cultura de Órgãos , Punções/instrumentação , Punções/métodosRESUMO
Robot-assisted cell microinjection, which is precise and can enable a high throughput, is attracting interest from researchers. Conventional probe-type cell microforce sensors have some real-time injection force measurement limitations, which prevent their integration in a cell microinjection robot. In this paper, a novel supported-beam based cell micro-force sensor with a piezoelectric polyvinylidine fluoride film used as the sensing element is described, which was designed to solve the real-time force-sensing problem during a robotic microinjection manipulation, and theoretical mechanical and electrical models of the sensor function are derived. Furthermore, an array based cell-holding device with a trapezoidal microstructure is micro-fabricated, which serves to improve the force sensing speed and cell manipulation rates. Tests confirmed that the sensor showed good repeatability and a linearity of 1.82%. Finally, robot-assisted zebrafish embryo microinjection experiments were conducted. These results demonstrated the effectiveness of the sensor working with the robotic cell manipulation system. Moreover, the sensing structure, theoretical model, and fabrication method established in this study are not scale dependent. Smaller cells, e.g., mouse oocytes, could also be manipulated with this approach.