ABSTRACT
In vitro metastatic models are foreseen to introduce a breakthrough in the field of preclinical screening of more functional small-molecule pharmaceuticals and biologics. To achieve this goal, the complexity of current in vitro systems requests an appropriate upgrade to approach the three-dimensional (3D) in vivo metastatic disease. Here, we explored the potential of our 3D ß-tricalcium phosphate (ß-TCP) model of neuroblastoma bone metastasis for drug toxicity assessment. Tailor-made scaffolds with interconnected channels were produced by combining 3D printing and slip casting method. The organization of neuroblastoma cells into a mesenchymal stromal cell (MSC) network, cultured under bioactive conditions provided by ß-TCP, was monitored by two-photon microscopy. Deposition of extracellular matrix protein Collagen I by MSCs and persistent growth of tumor cells confirmed the cell-supportive performance of our 3D model. When different neuroblastoma cells were treated with conventional chemotherapeutics, the ß-TCP model provided the necessary reproducibility and accuracy of experimental readouts. Drug efficacy evaluation was done for 3D and 2D cell cultures, highlighting the need for a higher dose of chemotherapeutics under 3D conditions to achieve the expected cytotoxicity in tumor cells. Our results confirm the importance of 3D geometry in driving native connectivity between nonmalignant and tumor cells and sustain ß-TCP scaffolds as a reliable and affordable drug screening platform for use in the early stages of drug discovery.
Subject(s)
Neuroblastoma , Tissue Scaffolds , Humans , Osteogenesis , Reproducibility of Results , Neuroblastoma/drug therapy , Neuroblastoma/pathologyABSTRACT
Advanced in vitro systems such as multicellular spheroids and lab-on-a-chip devices have been developed, but often fall short in reproducing the tissue scale and self-organization of human diseases. A bioprinted artificial tumor model is introduced with endothelial and stromal cells self-organizing into perfusable and functional vascular structures. This model uses 3D hydrogel matrices to embed multicellular tumor spheroids, allowing them to grow to mesoscopic scales and to interact with endothelial cells. It is shown that angiogenic multicellular tumor spheroids promote the growth of a vascular network, which in turn further enhances the growth of cocultivated tumor spheroids. The self-developed vascular structure infiltrates the tumor spheroids, forms functional connections with the bioprinted endothelium, and can be perfused by erythrocytes and polystyrene microspheres. Moreover, cancer cells migrate spontaneously from the tumor spheroid through the self-assembled vascular network into the fluid flow. Additionally, tumor type specific characteristics of desmoplasia, angiogenesis, and metastatic propensity are preserved between patient-derived samples and tumors derived from this same material growing in the bioreactors. Overall, this modular approach opens up new avenues for studying tumor pathophysiology and cellular interactions in vitro, providing a platform for advanced drug testing while reducing the need for in vivo experimentation.
Subject(s)
Bioprinting , Neoplasms , Humans , Spheroids, Cellular/pathology , Hydrogels/chemistry , Neoplasms/pathology , Human Umbilical Vein Endothelial Cells , Tissue EngineeringABSTRACT
Introduction: Recently, a special bullet shooting stunner for heavy cattle has been developed that fires a bullet instead of a bolt. In the search for a suitable ammunition, the following criteria must be met: First, the energy of the bullet must be sufficient to penetrate the thick frontal bones of heavy cattle. Second, the injury potential at the corresponding penetration depth should preferably be large in order to damage brain tissue relevant to stunning. Third, the bullet must not perforate the occipital bone (over-penetration). Methods: Four different bullet types [Hornady FTX, Hydra-Shok, Black Mamba, and a common full metal jacket (FMJ) bullet] were evaluated in a series of experiments on soap blocks and removed bone plates followed by computed tomography examinations. Penetration potential was evaluated in terms of kinetic energy relative to the caliber of the bullet, i.e., mean energy density (ED). Injury potential was evaluated by the mean extent of the cavity volume (e CV ) at the relevant penetration depth of 5.5 to 7.5 cm in the soap block. Results: All four bullet types passed through the frontal bone plate. The ED was 17.50 J/mm2 (Hornady FTX), 17.46 J/mm2 (Hydra-Shok), 13.47 J/mm2 (Black Mamba), and 13.47 J/mm2 (FMJ). The Hornady FTX and the Hydra-Shok each fragmented heavily. The FMJ was excluded after three experiments due to over-penetrations. The e CV was e CV = 3.77 cm2 (Hornady FTX), 2.71 cm2 (Hydra-Shok), and 1.31 cm2 (Black Mamba), with a significant difference (p = 0.006) between the Hornady FTX and the Black Mamba. Discussion: For use in heavy cattle, the Hornady FTX and the Hydra-Shok are recommended due to the larger e CV than the Black Mamba.
ABSTRACT
A key challenge for the discovery of novel molecular targets and therapeutics against pediatric bone metastatic disease is the lack of bona fide in vitro cell models. Here, we show that a beta-tricalcium phosphate (ß-TCP) multicellular 3D in vitro bone microtissue model reconstitutes key phenotypic and transcriptional patterns of native metastatic tumor cells while promoting their stemness and proinvasive features. Comparing planar with interconnected channeled scaffolds, we identified geometry as a dominant orchestrator of proangiogenic traits in neuroblastoma tumor cells. On the other hand, the ß-TCP-determined gene signature was DNA replication related. Jointly, the geometry and chemical impact of ß-TCP revealed a prometastatic landscape of the engineered tumor microenvironment. The proposed 3D multicellular in vitro model of pediatric bone metastatic disease may advance further analysis of the molecular, genetic and metabolic bases of the disease and allow more efficient preclinical target validations.
ABSTRACT
The combination of adipose-derived stem cells (ASCs) and dermal scaffolds has been shown to be an approach with high potential in soft tissue reconstruction. The addition of dermal templates to skin grafts can increase graft survival through angiogenesis, improve regeneration and healing time, and enhance the overall appearance. However, it remains unknown whether the addition of nanofat-containing ASCs to this construct could effectively facilitate the creation of a multi-layer biological regenerative graft, which could possibly be used for soft tissue reconstruction in the future in a single operation. Initially, microfat was harvested using Coleman's technique, then isolated through the strict protocol using Tonnard's technique. Finally, centrifugation, emulsification, and filtration were conducted to seed the filtered nanofat-containing ASCs onto Matriderm for sterile ex vivo cellular enrichment. After seeding, a resazurin-based reagent was added, and the construct was visualized using two-photon microscopy. Within 1 h of incubation, viable ASCs were detected and attached to the top layer of the scaffold. This experimental ex vivo note opens more dimensions and horizons towards the combination of ASCs and collagen-elastin matrices (i.e., dermal scaffolds) as an effective approach in soft tissue regeneration. The proposed multi-layered structure containing nanofat and dermal template (Lipoderm) may be used, in the future, as a biological regenerative graft for wound defect reconstruction and regeneration in a single operation and can also be combined with skin grafts. Such protocols may optimize the skin graft results by creating a multi-layer soft tissue reconstruction template, leading to more optimal regeneration and aesthetic outcomes.
Subject(s)
Plastic Surgery Procedures , Surgery, Plastic , Adipose Tissue/transplantation , Adipocytes/transplantation , Wound HealingABSTRACT
Polymeric micelles are increasingly explored for tumor-targeted drug delivery. CriPec® technology enables the generation of core-crosslinked polymeric micelles (CCPMs) based on thermosensitive (mPEG-b-pHPMAmLacn) block copolymers, with high drug loading capacity, tailorable size, and controlled drug release kinetics. In this study, we decorated clinical-stage CCPM with the αvß3 integrin-targeted cyclic arginine-glycine-aspartic acid (cRGD) peptide, which is one of the most well-known active targeting ligands evaluated preclinically and clinically. Using a panel of cell lines with different expression levels of the αvß3 integrin receptor and exploring both static and dynamic incubation conditions, we studied the benefit of decorating CCPM with different densities of cRGD. We show that incubation time and temperature, as well as the expression levels of αvß3 integrin by target cells, positively influence cRGD-CCPM uptake, as demonstated by immunofluorescence staining and fluorescence microscopy. We demonstrate that even very low decoration densities (i.e., 1 mol % cRGD) result in increased engagement and uptake by target cells as compared to peptide-free control CCPM, and that high cRGD decoration densities do not result in a proportional increase in internalization. In this context, it should be kept in mind that a more extensive presence of targeting ligands on the surface of nanomedicines may affect their pharmacokinetic and biodistribution profile. Thus, we suggest a relatively low cRGD decoration density as most suitable for in vivo application.
Subject(s)
Integrin beta3 , Micelles , Tissue Distribution , Drug Delivery Systems , Polymers , Cell Line, Tumor , Peptides, CyclicABSTRACT
The COVID-19 pandemic is one of the most pressing issues at present. A question which is particularly important for governments and policy makers is the following: Does the virus spread in the same way in different countries? Or are there significant differences in the development of the epidemic? In this paper, we devise new inference methods that allow to detect differences in the development of the COVID-19 epidemic across countries in a statistically rigorous way. In our empirical study, we use the methods to compare the outbreak patterns of the epidemic in a number of European countries.
ABSTRACT
Intravital microscopy (IVM) expands our understanding of cellular and molecular processes, with applications ranging from fundamental biology to (patho)physiology and immunology, as well as from drug delivery to drug processing and drug efficacy testing. In this review, we highlight modalities, methods and model organisms that make up today's IVM landscape, and we present how IVM - via its high spatiotemporal resolution - enables analysis of metabolites, small molecules, nanoparticles, immune cells, and the (tumor) tissue microenvironment. We furthermore present examples of how IVM facilitates the elucidation of nanomedicine kinetics and targeting mechanisms, as well as of biological processes such as immune cell death, host-pathogen interactions, metabolic states, and disease progression. We conclude by discussing the prospects of IVM clinical translation and examining the integration of machine learning in future IVM practice.
Subject(s)
Intravital Microscopy , Neoplasms , Drug Delivery Systems , Humans , Neoplasms/drug therapy , Tumor MicroenvironmentABSTRACT
Since the embedding of the principles of the 3Rs (Replacement, Reduction and Refinement) in national and international regulations on the use of animals, scientists have been challenged to find ways to reduce the number of animals in their research. Here, we present a digital platform, called '3R Backboard', linked to a laboratory animal management system, which facilitates sharing of surplus biological materials from animals (e.g. tissues, organs and cells) to other research teams. Based on information provided, such as genotype, age and sex, other animal workers were able to indicate their interest in collecting specific tissues and to communicate with the person providing the animals. A short pilot study of this approach conducted in a limited academic environment presented strong evidence of its effectiveness and resulted in a notable reduction of the number of mice used. In addition, the use of 3R Blackboard led to resource saving, knowledge exchange and even establishment of new collaboration.
Subject(s)
Animal Experimentation , Animal Testing Alternatives , Animal Welfare , Animals , Animals, Laboratory , Humans , Mice , Pilot ProjectsABSTRACT
BACKGROUND: In psychiatry, psychosomatics and psychotherapy, basic documentation (BaDo) is used as a quality assurance tool. For the field of child, adolescent and family psychosomatics, there is no uniform BaDo that can be used across facilities and care areas. The aim of the study was to propose a catalog of characteristics for the context of psychosomatic treatment of children and adolescents on the basis of a synoptic comparison of established BaDos METHODS: In the context of a qualitative document analysis, BaDo items from the children/youth and adult sector were evaluated in content analysis along a category system. The resulting aspects were then classified according to age and multidisciplinary content and evaluated with regard to their child/youth specificity. Descriptive statistical analysis of the results was performed RESULTS: Aspects of the categories Family Anamnesis and Biographical Anamnesis specified a BaDo for children and adolescents. For BaDos from the psychosomatic field, a record of pre-treatments was accentuated across age groups. The recording of socio-demographic data had to be adapted conceptually to the age-related needs of children and adolescents. CONCLUSION: On the basis of an empirical approach, a modular BaDo for child, youth and family psychosomatics could be formulated that enables institutional, sectoral and interdisciplinary evaluations. In a next step, the instrument should be evaluated in an application study and be consented to on a broad level.
Subject(s)
Documentation , Psychiatry , Adolescent , Adult , Child , Documentation/methods , Family , Humans , PsychotherapyABSTRACT
BACKGROUND/OBJECTIVES: Antibiotic indication documentation at the time of order entry is mandated by the Joint Commission. Inclusion of indication at order entry may have an impact on the time to administration. Our primary objective was to evaluate agreement between indication selected during order entry and clinical notes. Our secondary objective was to observe if there was a change in time to administration after indications were required during order entry. METHODS: Patients ≤18 years old who received ≥1 dose of vancomycin or ceftriaxone during a preintervention period and 3 postintervention periods were included. Indication for use, agreement between order and clinical note, and timing of antibiotic administration were collected. RESULTS: Most common indication for vancomycin (total: 789) was sepsis (26%, n = 204). Common indications for ceftriaxone (total: 1071) were sepsis (12%, n = 127), perforated appendicitis (12%, n = 125), and urinary tract infection (10%, n = 107). Postintervention, agreement between the indication selected during order entry and indication documented in clinical note for ceftriaxone and vancomycin orders were 41% and 46%, respectively. Median time to administration decreased among patients who received ceftriaxone (P < .01) but had no significant impact on time to administration of vancomycin (P = .49). CONCLUSIONS: Indication for ceftriaxone and vancomycin selected during order entry and reported in clinical notes inconsistently matched. Inclusion of antibiotic indication may impact time to administration.
Subject(s)
Anti-Bacterial Agents , Sepsis , Adolescent , Anti-Bacterial Agents/therapeutic use , Ceftriaxone , Documentation , Humans , VancomycinABSTRACT
BACKGROUND/AIMS: Podocytes are lost in most glomerular diseases, leading to glomerulosclerosis and progressive kidney disease. It is generally assumed, that podocytes are exposed to the filtration flow and thus to significant shear forces driving their detachment from the glomerular basement membrane (GBM). In this context, foot process effacement has been proposed as potential adaptive response to increase adhesion of podocytes to the GBM. METHODS: We have tested these hypotheses using optical clearing and high-resolution 3-dimensional morphometric analysis in the isolated perfused murine kidney. We investigated the dynamics of podocyte detachment at different perfusion pressures (50, 300 and more than 450 mmHg) in healthy young or old mice (20 vs. 71 weeks of age), or mice injected with anti-GBM serum to induce global foot process effacement. RESULTS: Results show that healthy podocytes in young mice are tightly attached onto the GBM and even supramaximal pressures did not cause significant detachment. Compared to young mice, in aged mice and mice with anti-GBM nephritis and foot process effacement, gradual progressive loss of podocytes had occurred already before perfusion. High perfusion pressures resulted in a relatively minor additional loss of podocytes in aged mice. In mice with anti-GBM nephritis significant additional podocyte loss occurred at this early time point when increasing perfusion pressures to 300 mmHg or higher. CONCLUSION: This work provides the first experimental evidence that podocytes are extraordinarily resistant to acutely increased perfusion pressures in an ex vivo isolated kidney perfusion model. Only in glomerular disease, significant numbers of injured podocytes detached following acute increases in perfusion pressure.
Subject(s)
Glomerular Basement Membrane/pathology , Kidney Diseases/pathology , Podocytes/pathology , Aging , Animals , Cell Adhesion , Cell Survival , Female , Glomerular Basement Membrane/cytology , Male , Mice , Perfusion , Podocytes/cytology , PressureABSTRACT
Metastasis is a complex and multifactorial process highly dependent on the interaction between disseminated tumor cells and the pre-metastatic niche. The metastatic sites detected in the bone of patients affected by neuroblastoma (NB), a malignancy of the developing sympathetic nervous system, are particularly aggressive. To improve our current knowledge of metastatic tumor cell biology and improve treatment success, appropriate in vitro and in vivo models that more closely resemble the native metastatic niche are needed. In this study, the impact of the geometry of synthetic ß-tricalcium-phosphate (ß-TCP) structures on the interaction of NB tumor cells with the stromal component has been examined. The tumor microenvironment is dynamically shaped by the stroma, which sustains the growth of NB cells inside the metastatic niche. The 3D growth conditions are a determining factor for the cell proliferation rate in ß-TCP. With respect to planar counterparts, channeled 3D ß-TCP structures stimulate more interleukin-6 and Fibronectin production and define Connexin 43 distribution inside the cells. Together, these results highlight how the biomechanical properties of the 3D microenvironment enable tumor cells to form spheroid-shaped arrangements. This, in turn, facilitates their pro-migratory and pro-invasive patterns and mimics the in vivo situation by translating realistic mechanobiological cues to the metastatic NB.
Subject(s)
Cues , Neuroblastoma , Cell Line, Tumor , Humans , Printing, Three-Dimensional , Tumor MicroenvironmentABSTRACT
In recent years, transcriptional biosensors have become valuable tools in metabolic engineering as they allow semiquantitative determination of metabolites in single cells. Although being perfectly suitable tools for high-throughput screenings, application of transcriptional biosensors is often limited by the intrinsic characteristics of the individual sensor components and their interplay. In addition, biosensors often fail to work properly in heterologous host systems due to signal saturation at low intracellular metabolite concentrations, which typically limits their use in high-level producer strains at advanced engineering stages. We here introduce a biosensor design, which allows fine-tuning of important sensor parameters and restores the sensor response in a heterologous expression host. As a key feature of our design, the regulator activity is controlled through the expression level of the respective gene by different (synthetic) constitutive promoters selected for the used expression host. In this context, we constructed biosensors responding to basic amino acids or ring-hydroxylated phenylpropanoids for applications in Corynebacterium glutamicum and Escherichia coli. Detailed characterization of these biosensors in liquid cultures and during single-cell analysis using flow cytometry showed that the presented sensor design enables customization of important biosensor parameters as well as application of these sensors in relevant heterologous hosts.
ABSTRACT
OBJECTIVES: Workers in small and medium residential construction companies (≤50 employees) have a high risk of fall-related fatality or disability. However, little is known about effective ways to engage with this subsector for research and training. We tested whether insurance-documented fall-related claims during the past 12 months and lower familiarity with equipment motivated companies' representatives to engage with a fall protection survey. METHODS: Oregon's largest workers compensation insurer drew a random anonymous sample of small and medium residential construction that did (n = 197) and did not (n = 195) have a recent fall-related claim. Samples were stratified by size, trade, and region. Company representatives were emailed a 34-item questionnaire about equipment familiarity to enter a raffle to win fall-prevention equipment. We coded survey engagement binarily, indicating whether a participant completed at least half of the survey. Familiarity with 10 pieces of equipment was measured with a scale from 0 (never seen it) to 3 (use it frequently) points. RESULTS: The survey was initiated by 88 out of 392 representatives (22.4% response rate). Of those, 63 representatives provided the company identifier which was needed to establish claim status. Survey engagement was higher among representatives from companies with claims compared with those without (57.6 versus 42.4%, P = 0.16). Equipment familiarity was lower among company representatives with lower survey engagement (1.15 versus 1.56, P < 0.05). CONCLUSIONS: The survey had a relatively encouraging response rate for a hard-to-reach sector. The large but not statistically significant difference in survey engagement rates suggests that adverse events motivate companies to engage with fall protection research. Low equipment familiarity in the sample substantiates the need to identify effective engagement methods for fall protection practices.
Subject(s)
Accidental Falls , Accidental Falls/prevention & control , Humans , Occupational Exposure , Small Business , Surveys and Questionnaires , Workers' CompensationABSTRACT
Aim of the study: Deep carious lesions may cause irreversible pulpitis and the current endodontic treatment typically removes the whole dental pulp tissue, which finally reduces lifespan of the teeth. Nowadays, the most frequent treatment is based on removing the infected tissue and filling the root canal with inert synthetic materials. Tissue engineering approaches are important alternatives to the current treatment, because they can potentially maintain the biological function of the tooth instead of sacrificing it.Materials and Methods: In this study, we propose a tissue engineering approach based on a hand-held in situ bioprinting strategy. Our approach enabled bioprinting of cell-loaded collagen-based bioinks with suitable rheological, structural and biological properties, which allowed for vasculogenesis in the root canal.Results: The rheological properties of the bioprintable bioink were measured by oscillatory amplitude sweep testing and were corroborated by macroscopic evaluation after in vitro culture, in which printed bioinks maintained their original form without contraction. Moreover, we showed evidence for successful vasculogenesis in bioprintable bioinks with comparable quality and quantity to control fibrin and collagen non-bioprintable hydrogels.Conclusions: We conclude that hand-held bioprinting holds potential for in situ treatment of dental diseases with successful evidence for vascular tube formation, as an asset for maintenance of the biological function of the tooth.
Subject(s)
Bioprinting , Dental Pulp , Human Umbilical Vein Endothelial Cells/metabolism , Neovascularization, Physiologic , Printing, Three-Dimensional , Pulpitis/therapy , Regeneration , Dental Pulp/blood supply , Dental Pulp/physiology , Humans , Pulpitis/metabolism , Pulpitis/pathologyABSTRACT
Recent developments in optical tissue clearing have been difficult to apply for the morphometric analysis of organs with high cellular content and small functional structures, such as the kidney. Here, we establish combinations of genetic and immuno-labelling for single cell identification, tissue clearing and subsequent de-clarification for histoimmunopathology and transmission electron microscopy. Using advanced light microscopy and computational analyses, we investigated a murine model of crescentic nephritis, an inflammatory kidney disease typified by immune-mediated damage to glomeruli leading to the formation of hypercellular lesions and the rapid loss of kidney function induced by nephrotoxic serum. Results show a graded susceptibility of the glomeruli, significant podocyte loss and capillary injury. These effects are associated with activation of parietal epithelial cells and formation of glomerular lesions that may evolve and obstruct the kidney tubule, thereby explaining the loss of kidney function. Thus, our work provides new high-throughput endpoints for the analysis of complex tissues with single-cell resolution.
Subject(s)
Glomerulonephritis/pathology , Histocytological Preparation Techniques/methods , Imaging, Three-Dimensional , Podocytes/physiology , Single-Cell Analysis/methods , Animals , Capillaries , Disease Models, Animal , Disease Progression , Fluorescence , Fluorescent Dyes/chemistry , Genes, Reporter/genetics , Glomerulonephritis/immunology , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/genetics , Humans , Male , Mice , Mice, Transgenic , Microscopy, Electron, Transmission , Podocytes/ultrastructureABSTRACT
The Pringle maneuver (PM) has been widely used to control blood loss during liver resection. However, hepatic inflow occlusion can also result in hepatic ischemia-reperfusion injury (IRI), especially in patients with a cholestatic, fibrotic, or cirrhotic liver. Here we investigate a nitric oxide synthase (NOS) inhibitor N-Nitroarginine methyl ester (L-NAME) on IRI after the PM and partial hepatectomy of cholestatic livers induced by bile duct ligation (BDL) in rats. Control group (non-BDL/no treatment), BDL + T group (BDL/L-NAME treatment) and BDL group (BDL/no treatment) were analyzed. Cholestasis was induced by BDL in the L-NAME and BDL group and a 50% partial hepatectomy with PM was performed. L-NAME was injected before PM in the BDL + T group. Hepatocellular damage, portal venous flow, microcirculation, endothelial lining, and eNOS, iNOS, interleukin (IL)-6, and transforming growth factor-ß (TGF-ß) were evaluated. Microcirculation of the liver in the BDL + T group tended to be higher. Liver damage and apoptotic index were significantly lower and Ki-67 labeling index was higher in the BDL + T group while iNOS and TGF-ß expression was decreased. This was corroborated by a better preserved endothelial lining. L-NAME attenuated IRI following PM and improved proliferation/regeneration of cholestatic livers. These positive effects were considered as the result of improved hepatic microcirculation, prevention of iNOS formation, and TGF-ß mRNA upregulation.
Subject(s)
Cholestasis, Intrahepatic/complications , Cholestasis, Intrahepatic/metabolism , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Reperfusion Injury/complications , Reperfusion Injury/metabolism , Animals , Biomarkers , Cholestasis, Intrahepatic/pathology , Cytokines/metabolism , Disease Models, Animal , Hyaluronic Acid/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Immunohistochemistry , Inflammation Mediators/metabolism , Lipid Peroxidation/drug effects , Microcirculation/drug effects , Nitric Oxide/metabolism , Rats , Reperfusion Injury/pathologyABSTRACT
Corneal transplantation is the treatment of choice for patients with advanced corneal diseases. However, the outcome may be affected by graft rejection, high associated costs, surgical expertise, and most importantly the worldwide donor shortage. In recent years, bioprinting has emerged as an alternative method for fabricating tissue equivalents using autologous cells with architecture resembling the native tissue. In this study, we propose a freeform and cell-friendly drop-on-demand bioprinting strategy for creating corneal stromal 3D models as suitable implants. Corneal stromal keratocytes (CSK) were bioprinted in collagen-based bioinks as 3D biomimetic models and the geometrical outcome as well as the functionality of the bioprinted specimens were evaluated after in vitro culture. We showed that our bioprinting method is feasible to fabricate translucent corneal stromal equivalents with optical properties similar to native corneal stromal tissue, as proved by optical coherence tomography. Moreover, the bioprinted CSK were viable after the bioprinting process and maintained their native keratocyte phenotypes after 7 days in in vitro culture, as shown by immunocytochemistry. The proposed bioprinted human 3D corneal models can potentially be used clinically for patients with corneal stromal diseases.
Subject(s)
Bioprinting , Collagen/chemistry , Cornea , Ink , Keratinocytes/metabolism , Tissue Engineering , Adult , Aged , Aged, 80 and over , Cells, Cultured , Cornea/chemistry , Cornea/cytology , Cornea/metabolism , Female , Humans , Keratinocytes/cytology , Male , Middle AgedABSTRACT
In vitro cancer 3D models are valuable tools to provide mechanistic insight into solid tumor growth, invasion, and drug delivery. The 3D spheroid model of solid tumors has been the most popular cancer model in use until now. However, previous studies have shown that these spheroid models lack sufficient morphological parameters, which may affect their response to chemicals. In this work, we proposed the fabrication of miniaturized 3D cancer models using collagen type I-based bioprintable bioinks. In the context of a mimicking model for advanced neuroblastoma studies, we showed that cancer cells contained in bioprintable bioinks formed Homer Wright-like rosettes, maintained their proliferative capacities and produced an equivalent Vimentin-rich matrix unlike that of non-bioprintable bioinks which made for poorer models. In addition, bioprintable bioinks were successfully bioprinted as compartmentalized 3D models in the centimeter scale, which was not feasible using non-bioprintable bioinks. In contrast to non-bioprintable hydrogels, we did not observe contraction in their bioprintable counterparts, which is an advantage for prospective 3D bioprinted models that should attain stable rheological and mechanical properties after bioprinting. By adopting this proposed system for the use of patient-derived primary tumor cells, the approach could be introduced as a first line strategy in precision medicine for testing the response of neuroblastoma cells to drugs, especially when disease progresses rapidly or patients do not respond to actual therapy regimens.