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Cell functionality, driven by remarkable plasticity, is strongly influenced by mechanical forces that regulate mesenchymal stem cell (MSC) fate. This study explores the biomechanical properties of jaw periosteal cells (JPCs) and induced mesenchymal stem cells (iMSCs) under different culture conditions. We cultured both JPCs and iMSCs (n = 3) under normoxic and hypoxic environments, with and without osteogenic differentiation, and on laminin- or gelatin-coated substrates. Using atomic force microscopy, we measured cellular elasticity and Young’s modulus of calcium phosphate precipitates (CaPPs) formed under osteogenic conditions. Correlation analyses between cellular stiffness, quantity of CaPP deposition, and stiffness of formed CaPPs were evaluated. The results showed that iMSCs, despite their softer cellular consistency, tended to form CaPPs of higher elastic moduli than osteogenically differentiated JPCs. Particularly under normoxic conditions, JPCs formed stronger CaPPs with lower cellular stiffness profiles. Conversely, iMSCs cultivated under hypoxic conditions on laminin-coated surfaces produced stronger CaPPs while maintaining lower cellular stiffness. We conclude that JPCs and iMSCs display distinct biomechanical responses to culture conditions. While JPCs increase cellular stiffness during osteogenic differentiation, in particular under hypoxic conditions, iMSCs exhibit a decrease in stiffness, indicating a higher resistance to lower oxygen levels. In both cell types, a lower cellular stiffness profile correlates with enhanced mineralization, indicating that this biomechanical fingerprint serves as a critical marker for osteogenic differentiation.

Cell functionality, driven by remarkable plasticity, is strongly influenced by mechanical forces that regulate mesenchymal stem cell (MSC) fate. This study explores the biomechanical properties of jaw periosteal cells (JPCs) and induced mesenchymal stem cells (iMSCs) under different culture conditions. We cultured both JPCs and iMSCs (n = 3) under normoxic and hypoxic environments, with and without osteogenic differentiation, and on laminin- or gelatin-coated substrates. Using atomic force microscopy, we measured cellular elasticity and Young's modulus of calcium phosphate precipitates (CaPPs) formed under osteogenic conditions. Correlation analyses between cellular stiffness, quantity of CaPP deposition, and stiffness of formed CaPPs were evaluated. The results showed that iMSCs, despite their softer cellular consistency, tended to form CaPPs of higher elastic moduli than osteogenically differentiated JPCs. Particularly under normoxic conditions, JPCs formed stronger CaPPs with lower cellular stiffness profiles. Conversely, iMSCs cultivated under hypoxic conditions on laminin-coated surfaces produced stronger CaPPs while maintaining lower cellular stiffness. We conclude that JPCs and iMSCs display distinct biomechanical responses to culture conditions. While JPCs increase cellular stiffness during osteogenic differentiation, in particular under hypoxic conditions, iMSCs exhibit a decrease in stiffness, indicating a higher resistance to lower oxygen levels. In both cell types, a lower cellular stiffness profile correlates with enhanced mineralization, indicating that this biomechanical fingerprint serves as a critical marker for osteogenic differentiation.

Third-generation biomass production utilizing microalgae exhibits sustainable and environmentally friendly attributes, along with significant potential as a source of physiologically active compounds. However, the process of screening and localizing strains that are capable of producing high-value-added substances necessitates a significant amount of effort. In the present study, we have successfully isolated the indigenous marine diatom Odontella aurita OAOSH22 from the east coast of Korea. Afterwards, comprehensive analysis was conducted on its morphological, molecular, and biochemical characteristics. In addition, a series of experiments was conducted to analyze the effects of various environmental factors that should be considered during cultivation, such as water temperature, salinity, irradiance, and nutrients (particularly nitrate, silicate, phosphate, and iron). The morphological characteristics of the isolate were observed using optical and electron microscopes, and it exhibited features typical of O. aurita. Additionally, the molecular phylogenetic inference derived from the sequence of the small-subunit 18S rDNA confirmed the classification of the microalgal strain as O. aurita. This isolate has been confirmed to contain 7.1 mg g−1 dry cell weight (DCW) of fucoxanthin, a powerful antioxidant substance. In addition, this isolate contains 11.1 mg g−1 DCW of eicosapentaenoic acid (EPA), which is one of the nutritionally essential polyunsaturated fatty acids. Therefore, this indigenous isolate exhibits significant potential as a valuable source of bioactive substances for various bio-industrial applications.

Fucoxanthin is one of the light-harvesting pigments in brown microalgae, which is increasingly gaining attention due to its numerous health-promoting properties. Currently, the production of microalgal fucoxanthin is not yet feasible from an economic perspective. However, the cultivation of microalgae at favourable conditions holds great potential to increase the viability of this fucoxanthin source. Hence, this study aimed to review the fucoxanthin production of microalgae under different conditions systematically. A literature search was performed using the Web of Science, Scopus and PubMed databases. A total of 188 articles were downloaded and 28 articles were selected for the current review by two independent authors. Microalgae appeared to be a more reliable fucoxanthin source compared to macroalgae. Overall, a consensus fucoxanthin production condition was obtained and proposed: light intensity ranging from 10 to 100 µmol/m2/s could achieve a higher fucoxanthin content. However, the optimal light condition in producing fucoxanthin is species-specific. The current review serves as an antecedent by offering insights into the fucoxanthin-producing microalgae response to different culture factors via a systematic analysis. With the current findings and recommendations, the feasibility of producing fucoxanthin commercially could be enhanced and possibly achieve practical and sustainable fucoxanthin production.

Crop culture conditions are one of the important interfaces between food, the environment, and health, and an essential research area for maintaining social-ecological integrity. In recent years, it has been reported that the difference in culture conditions between monoculture with external inputs (in cultura) and self-organized ecological niches (in natura) is significant for the resulting physiological property of plants. It has also been suggested that there exist metabolic proxies in various foods that can separate these two culture conditions, which does not depend on a single component but on the distribution of various compounds. However, little has been studied in a time series of replicated production to quantify the reproducibility of these metabolomic features associated with culture conditions. In this study, we obtained metabolome data of coarse green tea (Camellia sinensis) grown in the same region in Japan under both in cultura and in natura culture conditions over the course of six years, and constructed a list of multiple components that separated the effects of culture conditions by statistical analysis, and estimated the metabolic functions of the compounds that contributed to the separation. The results suggest that naturally grown samples are rich in allelochemicals, such as phytochemicals, alkaloids, phenylpropanoids, steroids, as well as the compounds related to microorganisms and vitamin B6 that imply the interactions with the soil microbiome. The estimated physiological functions of the distinctive compounds suggest that the in natura crop production is not only beneficial with known properties of maintaining ecosystem health such as soil functions and pathogen control, but also for the augmentation of the plant secondary metabolites that support long-term health protective effects.

Upon activation T cells engage glucose metabolism to fuel the costly effector functions needed for a robust immune response. Consequently, the availability of glucose can impact on T cell function. The glucose concentrations used in conventional culture media and common metabolic assays are often artificially high, representing hyperglycaemic levels rarely present in vivo. We show here that reducing glucose concentration to physiological levels in culture differentially impacted on virus-specific compared to generically activated human CD8 T cell responses. In virus-specific T cells, limiting glucose availability significantly reduced the frequency of effector-cytokine producing T cells, but promoted the upregulation of CD69 and CD103 associated with an increased capacity for tissue retention. In contrast the functionality of generically activated T cells was largely unaffected and these showed reduced differentiation towards a residency phenotype. Furthermore, T cells being cultured at physiological glucose concentrations were more susceptible to viral infection. This setting resulted in significantly improved lentiviral transduction rates of primary cells. Our data suggest that CD8 T cells are exquisitely adapted to their niche and provide a reminder of the need to better mimic physiological conditions to study the complex nature of the human CD8 T cell immune response.

Much interest has been directed towards stem cells, both in basic and translational research, to understand basic stem cell biology and to develop new therapies for many disorders. In general, stem cells can be cultured with relative ease, however, most common culture methods for stem cells employ 2D techniques using plastic. These cultures do not well represent the stem cell niches in the body, which are delicate microenvironments composed of not only stem cells, but also supporting stromal cells, extracellular matrix, and growth factors. Therefore, researchers and clinicians have been seeking optimal stem cell preparations for basic research and clinical applications, and these might be attainable through 3D culture of stem cells. The 3D cultures recapitulate the in vivo cell-to-cell and cell-to-matrix interactions more effectively, and the cells in 3D cultures exhibit many unique and desirable characteristics. The culture of stem cells in 3D may employ various matrices or scaffolds, in addition to the cells, to support the complex structures. The goal of this Special Issue is to bring together recent research on 3D cultures of various stem cells to increase the basic understanding of stem cells and culture techniques, and also highlight stem cell preparations for possible novel therapeutic applications.