In vitro models最新文献

One major drawback of preclinical models to test drug-induced liver injury (DILI) is their inability to predict the interindividual difference of DILI effect in a population. Consequently, a high number of molecules that passed preclinical phases, fail clinical trials, and many FDA-approved drugs were removed from the market due to idiosyncratic DILI. We use a proprietary-depleted human serum-based cell educating technology to generate donor-dependent spheroids with distinct morphology and functionality. We demonstrate that educated spheroids could capture the large variations in susceptibility to drug-induced liver injury between donors. We show that the model could predict clinical apparent DILI risk with a high specificity and sensitivity. We provide evidence that the model could address non-genetic factor-associated DILI risk and severity such as age or sex. Our study supports the benefit of using donor-dependent educated spheroids for hepatotoxicity evaluation in preclinical phase or in an exploratory study clinical trial phase 2 to provide a robust safety profile to a drug.

Purpose: Regular exercise is known to reduce cancer risk and may prevent metastases, however, modelling this in vitro is challenging due the heterogeneity of the tumour microenvironment. Exercised serum can be used to capture changes in cellular signalling components in response to different types and durations of exercise. In this study, exercised serum from long-term endurance runners and sprinters of different ages was used to evaluate the impact of exercise on the invasiveness of breast cancer cells and mesenchymal stem cells in vitro.

Methods: Exercised serum from long-term trained younger and older endurance runners and sprinters was used to supplement cell culture media in the 3D culture of spheroids containing breast cancer cells or mesenchymal stem cells. Spheroids were generated in a 3D semi-solid matrix and cell invasion was measured using ImageJ software. Statistical analyses of invasion were conducted using one-way ANOVAs.

Results: Invasion was significantly greater in cells cultured with serum from older, inactive participants compared to young, inactive participants (YC vs OC; F _(1,3) = 37.135, P = 0.009). No significant difference was found in the invasion of MDA-MB-231 breast cancer cells cultured in serum from older, long-term endurance runners and younger, long-term endurance runners (YE vs OE; F _(1,3) = 5.178, P = 0.107), suggesting a protective effect of endurance running against the pro-invasive effects of ageing.

Conclusion: This is the first study of its kind to demonstrate the protective effects of long-term exercise training type in two populations of different ages against the invasiveness of breast cancer cells in vitro.

Identifying and monitoring the presence of cancer metastasis and highlighting inter-and intratumoral heterogeneity is a central tenet of targeted precision oncology medicine (POM). This process of relocation of cancer cells is often referred to as the missing link between a tumor and metastasis. In recent years, microfluidic technologies have been developed to isolate a plethora of different biomarkers, such as circulating tumor cells (CTCs), tumor-derived vesicles (exosomes), or cell/free nucleic acids and proteins directly from patients' blood samples. With the advent of microfluidic developments, minimally invasive and quantitative assessment of different tumors is becoming a reality. This short review article will touch briefly on how microfluidics at early-stage achievements can be combined or developed with the active vs passive microfluidic technologies, depending on whether they utilize external fields and forces (active) or just microchannel geometry and inherent fluid forces (passive) from the market to precision oncology research and our future prospectives in terms of the emergence of ultralow cost and rapid prototyping of microfluidics in precision oncology.

Previously, we have developed a novel porous hydroxyapatite/poly l-lactic-co-caprolactone (HA/PLCL) composite sandwich beam as a new scaffold material for bone regeneration. This work presents the study of bending fracture mechanisms and microdamage of porous hydroxyapatite/poly L-lactic-acid (HA/PLLA) sandwich beam, in comparison to the previous developed HA/PLCL sandwich beam. Both beams were fabricated using the sandwich method in which the single porous composite beams were layered in between two porous polymer layers of their kind. Three-point bending tests were performed to assess their mechanical properties, and their microstructures along with the damage mechanisms were examined using field emission-scanning electron microscope (FE-SEM). Their crystalline structures and thermal properties were analyzed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis, and differential scanning calorimetry (DSC) measurements. The microdamage and fracture mechanisms were then characterized by stepwise crack formations. It was found that HA/PLLA composite sandwich beam possessed higher mechanical properties compared to HA/PLCL sandwich beam, resulting from higher stiffness of PLLA polymer. PLCL layer showed a vast ductile fracture, with elongated PLCL strips, while the fracture surfaces observed on the PLLA layer have a relatively brittle fracture pattern with some polymeric pores that were still visible. Three stages of damage were observed on both beams with different locations of crack initiation, indicating that different polymer materials do affect the fracture behavior of each beam.

Purpose: Human induced pluripotent stem cell (hiPSC)-derived lung cell types such as alveolar epithelial cells are promising for toxicological and pharmaceutical in vitro screenings. Reproducible differentiation processes are highly demanded, but protocols which are suitable for the high-throughput generation of lung cell types from hiPSCs are lacking.

Methods: In this study, a new approach for the hiPSC-differentiation in alveolar epithelial-like cells type 2 under dynamic 3D-conditions in a suspension bioreactor is presented. Gene and protein expression analyses of key markers during the embryonal lung development have been performed in comparison to cells differentiated under static 2D-conditions to evaluate the differentiation efficacy of the new bioreactor-based approach. Finally, the resulting cells were infected by SARS-CoV-2 pseudotypes to demonstrate their functionality and suitability for e.g. COVID-19 drug development.

Results: The dynamic bioreactor is suitable to differentiate hiPSCs in spheroids, which express relevant lung markers in each developmental stage on gene and protein level. The 3D method is able to significantly increase the expression of some markers in comparison to conventional 2D differentiation. 3D-differentiated alveolar epithelial-like cells express functional SARS-CoV-2 receptors and can display the viral infection.

Conclusion: The presented dynamic 3D-differentiation is a promising, new approach to generate alveolar epithelial-like cells from hiPSCs as cell source for in vitro lung models.

Supplementary information: The online version contains supplementary material available at 10.1007/s44164-023-00052-1.

The main drawbacks of blood-contacting metallic devices are corrosion and thrombus formation on the surface, so polymeric coatings have been proposed to improve its hemocompatibility. Sulfated chitosan (SC) was obtained from natural chitosan (NC) reaction with chlorosulfonic acid to be used as a coating for metallic surfaces. The sulfated chitosan showed no platelet aggregation, an extended clotting time, and non-toxicity to rat fibroblast L929 cells. In this study, stainless steel (SS) and titanium alloys modified with TiO₂ nanotube (NTT) growth received a NC and SC coating. The titanium surface coated with sulfated chitosan presented the lowest percentage of platelet coverage area. Sulfated chitosan proved to be a promising material for use as a coating for metallic surfaces applied for cardiovascular devices.

Peripheral nerve injuries represent a major clinical challenge, if nerve ends retract, there is no spontaneous regeneration, and grafts are required to proximate the nerve ends and give continuity to the nerve. The nerve guidance conduits (NGCs) presented in this work are silk fibroin (SF)-based, which is biocompatible and very versatile. The formation of conduits is obtained by forming a covalently cross-linked hydrogel in two concentric moulds, and the inner longitudinally aligned pattern of the SF NGCs is obtained through the use of a patterned inner mould. SF NGCs with two wall thicknesses of ~ 200 to ~ 400 μm are synthesized. Their physicochemical and mechanical characteristics have shown improved properties when the wall thickness is thicker such as resistance to kinking, which is of special importance as conduits might also be used to substitute nerves in flexible body parts. The Young modulus is higher for conduits with inner pattern, and none of the conduits has shown any salt deposition in presence of simulated body fluid, meaning they do not calcify; thus, the regeneration does not get impaired when conduits have contact with body fluids. In vitro studies demonstrated the biocompatibility of the SF NGCs; proliferation is enhanced when iSCs are cultured on top of conduits with longitudinally aligned pattern. BJ fibroblasts cannot infiltrate through the SF wall, avoiding scar tissue formation on the lumen of the graft when used in vivo. These conduits have been demonstrated to be very versatile and fulfil with the requirements for their use in PNR.

Supplementary information: The online version contains supplementary material available at 10.1007/s44164-023-00050-3.

Nanostructured inorganic biomaterial emerged as the most essential platform to address traumatic and non-traumatic conditions of hard tissues in the current scenario. Synthetic inorganic biomaterials serve as an efficient and pathogen-free choice that overcomes the obstructions associated with autografts and allografts to promote new tissue regeneration, since nano-hydroxyapatite (nHAp) is a biomaterial that mimics the natural mineral composition of bones and teeth of human hard tissues, which is widely employed in orthopedics and dentistry. The nHAp-based materials exhibit bioactive, biocompatible, and osteoconductive features under in vitro and in vivo conditions. The brittle nature of synthetic nHAp leads to weak mechanical properties, which eventually confines the utility of nHAp in load-bearing applications. Hence, this review focuses on the recent trends in the fabrication and investigation of nHAp-based polymer nanocomposite scaffolds for bone regeneration. Employing different polymers and fabrication strategies would efficiently tailor the physicochemical properties, and tailor-made mechanical properties in competence with biodegradation, thereby enhancing their potential in biomedical utility, and exploring their efficacy under in vitro and in vivo conditions to make "HAp-based smart-biomaterials" for bone tissue engineering.

Purpose: Ischemic brain injury occurs when there is reduced or complete disruption of blood flow to a brain region, such as in stroke or severe traumatic brain injury. Even short interruptions can lead to devastating effects including excitotoxicity and widespread cell death. Despite many decades of research, there are still very few therapeutic options for patients suffering from brain ischemia.

Methods: We developed an in vitro brain ischemia model using our previously established 3D spheroids derived from primary postnatal rat cortex. These spheroids provide an in vivo-relevant model containing a similar cellular composition to the native cortex and a cell-synthesized extracellular matrix. This model is cost-effective, highly reproducible, and can be produced in a high-throughput manner, making it an ideal candidate for screening potential therapeutics. To study the cellular and molecular mechanisms of stroke in this model, spheroids were deprived of glucose, oxygen, or both oxygen and glucose for 24 h.

Results: Both oxygen and oxygen-glucose deprived spheroids demonstrated many of the hallmarks of ischemic brain injury, including a decrease in metabolism, an increase in neural dysfunction, breakdown in the neurovascular unit, and an increase in reactive astrocytes. Pretreatment of spheroids with the antioxidant agent N-acetylcysteine (NAC) mitigated the decrease in ATP after oxygen-glucose deprivation, was partially neuroprotective, and enhanced the expression of laminin.

Conclusion: This 3D cortical spheroid model provides a platform for studying ischemic injury and has the potential for screening therapeutics.

Supplementary information: The online version contains supplementary material available at 10.1007/s44164-023-00046-z.

The intestinal barrier is a complex interface of the human body, possessing the largest contact surface to nutrients and antigens and containing a major part of the immune system. It has to deal with continuous exposure to a broad mixture of essential, harmful, or useless substances and particles. In the context of plastic pollution and the ubiquitous occurrence of micro- and nanoplastics, oral exposure to such particles is of particular interest. Standard intestinal in vitro models, however, are unable to mimic the role of the immune system in the particle-exposed intestine. To allow for a closer look on the effect of particles on the intestinal immune system, we here developed a co-culture model to enable investigation of the epithelial brush border monolayer in a healthy and inflamed state. The model is based on well-established Caco-2 intestinal epithelial cells cultured in a Transwell™ system. Intraepithelial immune cells were mimicked by THP-1-derived M0-macrophages and MUTZ-3-derived dendritic cells. To fulfill the requirements needed for the investigation of particles, the co-culture system was developed without an additional matrix layer. Cell-cell contacts were established between interstitial and immune cells, and the Caco-2 standard cell culture medium was used, which is well-characterized for its role in defining the identity of particle dispersions. The model was characterized using confocal microscopy, membrane integrity measurements, and cytokine release assays from inflamed and healthy cells. Finally, the new co-culture model was used for investigation on polylactic acid, melamine formaldehyde resin, and polymethylmethacrylate plastic micro- and nanoparticles.

Supplementary information: The online version contains supplementary material available at 10.1007/s44164-023-00047-y.