In vitro models最新文献

Purpose: Cellulose nanocrystals (CNC) play a promising role in the development of new advanced materials. The growing demand of CNC-containing products in the food industry will lead to an increased human exposure through oral uptake. To date, there is a dearth of studies reporting on the risks which CNC pose to human health following ingestion. In vitro models, which lack physiological accuracy, are often used to justify animal experiments in the field of nanosafety assessment. Nevertheless, ex vivo models of the intestine pose promising alternatives to in vivo experiments.

Methods: Two ex vivo models, a microfluidic chip based on porcine intestinal mucus and the Ussing chamber apparatus with tissue from abattoirs, which aim to complement in vitro models, are characterized by investigating the transport and toxicity of CNC through them in comparison to an in vitro triple co-culture model. Silver nanoparticles were included in this study as well-known and characterized nanomaterials for comparative purposes.

Results: Study results show that CNC cross the intestinal mucus layer but do not pass the intestinal tissue barrier ex vivo and in vitro; furthermore, no toxic effects were observed under exposure conditions tested.

Conclusion: These ex vivo models present complementary methods to the existing standardized in vitro and in silico methods to support data generation under physiologically relevant conditions without the use of animals. This multi-model approach offers an enhanced understanding of the complex interaction between new materials and human tissue and aligns with the flexible approach of IATA (Integrated Approaches to Testing and Assessment) and NAMs (New Approach Methods) for chemical and drug safety assessment.

Supplementary information: The online version contains supplementary material available at 10.1007/s44164-023-00056-x.

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.