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Nuernberg, E.

Publications and source records attributed to Nuernberg, E..

3 recordsLinked to original sources

Advanced 3D spheroid-based skin models and deep-learning based image analysis enable in-depth investigation of keratinocyte differentiation and barrier function

To date, a panel of different biological models have been used in skin research, ranging from in vivo testing to 2D and 3D cultures. Among these, organotypic skin models represent the current gold standard for preclinical dermatology and toxicology studies. However, they are variable in quality and require long maturation times and a lot of work and cells, the latter often of primary origin. Here, we propose dermal-epidermal spheroids as an alternative model that balances physiological relevance and throughput. Next to corresponding full thickness skin models, different fibroblast/keratinocyte coculture spheroids were generated. These used the commonly employed HaCaT cells as well as two recently immortalized keratinocyte cell lines, NHK-SV/TERT and NHK-E6/E7. To investigate their differentiation with detailed spatio-temporal resolution, a deep-learning segmentation-based pipeline, capable of revealing nuclear morphology and positioning as well as marker expression with single-cell precision, was developed and applied. Moreover, the formation of a functional barrier was assessed by live-imaging of Lucifer yellow diffusion. These experiments identified the NHK-E6/E7 cell line as the most and HaCaT cells as the least suitable alternative to primary keratinocytes in both spheroids and full thickness models. Furthermore, NHK-based coculture spheroids displayed functional maturation, including stratification, cornification, and barrier formation, closely recapitulating these features of corresponding full thickness models. Given the scalability and compatibility with automation, these micro-skin fibroblast/NHK-based 3D coculture spheroids might represent a promising new platform for pharmaceutical, cosmetic, and toxicological testing.

bioengineering↗

From in vitro to in silico: a pipeline for generating virtual tissue simulations from real image data

3D cell culture models replicate tissue complexity, aiming to study cellular interactions and responses in a more physiologically relevant environment compared to traditional 2D cultures. However, the spherical structure of these models makes it difficult to extract meaningful data, necessitating advanced techniques for proper analysis. In silico simulations enhance research by predicting cellular behaviors and therapeutic responses, providing a powerful tool to complement experimental approaches. Despite their potential, these simulations often require advanced computational skills and significant resources, creating a barrier for many researchers. To address these challenges, we developed an accessible pipeline using open-source software to facilitate virtual tissue simulations. Our approach employs the Cellular Potts Model, a versatile framework for simulating cellular behaviors in tissues. The simulations are constructed from real world 3D image stacks of cancer spheroids, ensuring the virtual models are rooted in experimental data. By introducing a new metric for parameter optimization, we enable the creation of realistic simulations without requiring extensive computational expertise. This pipeline benefits researchers wanting to incorporate computational biology into their methods, even if they do not possess extensive expertise in this area. By reducing the technical barriers associated with advanced computational modeling, our pipeline allows more researchers to utilize these powerful tools. Our approach aims to foster broader use of in silico methods in disease research, contributing to a deeper understanding of disease biology and the refinement of therapeutic interventions.

biophysics↗

A Multiparametric Analysis Reveals Differential Behavior of Spheroid Cultures on Distinct Ultra-Low Attachment Plates Types

Spheroids have become principal three-dimensional biological models to study cancer, developmental processes, and drug efficacy. For spheroid generation, ultra-low attachment plates are noteworthy due to their simplicity, compatibility with automation, and experimental and commercial accessibility. Nonetheless, it is unknown whether and to what degree the plate type impacts spheroid formation and biology. This study employed automated brightfield microscopy to systematically compare the size and eccentricity of spheroids formed in six different plate types using four distinct human cell lines, i.e., CCD-1137Sk fibroblasts, HaCaT keratinocytes, and MDA-MB-231 and HT-29 cancer cells. Results showed that all plate types exhibited similar sphe-roid-forming capabilities, and the gross patterns of growth or shrinkage during four days after seeding were comparable. Yet, size and eccentricity varied systematically among specific cell lines and plate types. A confocal wholemount analysis by a novel pipeline of AI-based 3D-image analysis procedures revealed changes in cell proliferation, cell number, nuclear volume, and keratino-cyte differentiation, which were accompanied by altered YAP1-signals. The findings show that the plate type may influence the outcome of experimental campaigns. It is advisable to scan different plate types for the optimal configuration for a specific investigation instead of using one standard plate for all kinds of applications.

cancer biology↗