bims-redobi 2024-08-11 papers

Acta Biomater. 2024 Aug 01. pii: S1742-7061(24)00427-6. [Epub ahead of print]

Zwitterionic-hydrogel-based Sensing System Enables Real-time ROS Monitoring for Ultra-long Hypothermic Cell Preservation.

Yunqing Tian, Yiming Ma, Yuxiang Kang, Shu Tian, Qingsi Li, Lei Zhang, Jing Yang.

Hypothermic preservation (HP) is highly desired for the maintenance of the viability of living cell specimens, e.g. rare cells in whole-blood samples or therapeutic cells, in an unfrozen state. However, the extension of the viable preservation time is a challenge because of the multiple injuries suffered by hypothermically preserved cells. Here, based on a dynamic bond crosslinked zwitterionic hydrogel, we established a sensing preservation system that could monitor the levels of reactive oxygen species (ROS) via real-time electronic signals and intelligent control of antioxidant addition, to completely prevent an excess of ROS in the whole-cell specimen. Furthermore, the hydrogel-based system can counter the extracellular-matrix-loss-induced anoikis of living cells. Based on the design aimed at affording protection against two primary HP injuries (i.e. ROS overproduction and anoikis) to cells, this system extended the preservation time of cell specimens under refrigerated conditions to 24 days. After preservation, the use of a mild cell retrieval process guaranteed the activity of the preserved living cells. This work not only possesses the potential to facilitate intelligent cell-based clinical applications, but also paves the way for the preparation of living materials that can host programmed cells with long-term survival. STATEMENT OF SIGNIFICANCE: An intelligent system based on a zwitterionic sensing hydrogel is established, which can afford ultra-long hypothermic cell-preservation times of up to 24 days. The system enables the real-time monitoring of ROS overproduction and intelligent antioxidant addition, because of the merging of the smart hydrogel with a computer intelligent detection and control system. Furthermore, the automatic addition of an antioxidant according to the ROS-signal changes produced by the ZBA hydrogel effectively prevented HP lesions, including ROS over-production and ECM loss, in the preserved living cells. Subsequently, the system could also be gently dissociated, to retrieve the preserved cells. This work provides a solution for the real-time monitoring and long-term HP of living specimens, which holds the promise of benefiting cell-based medicine and the development of genetically programmed cell-based living materials.

Keywords: hypothermic cell preservation; real-time monitoring; sensing system; zwitterionic hydrogels

DOI: https://doi.org/10.1016/j.actbio.2024.07.043

Biosens Bioelectron. 2024 Jul 31. pii: S0956-5663(24)00600-6. [Epub ahead of print]263 116595

IMSIS: An instrumented microphysiological system with integrated sensors for monitoring cellular metabolic activities.

Ming-Hao Cheng, Ryan Way, Kyle Fresa, Giovana D Catandi, Elaine Carnevale, Adam J Chicco, Thomas W Chen.

Well plates are widely used in biological experiments, particularly in pharmaceutical sciences and cell biology. Its popularity stems from its versatility to support a variety of fluorescent markers for high throughput monitoring of cellular activities. However, using fluorescent markers in traditional well plates has its own challenges, namely, they can be potentially toxic to cells, and thus, may perturb their biological functions; and it is difficult to monitor multiple analytes concurrently and in real-time inside each well. This paper presents a fully instrumented microphysiological system with integrated sensors (IMSIS) with a similar well format. Each well in the microphysiological system has a set of sensors for monitoring multiple metabolic analytes in real-time. The IMSIS platform is supported by integrated bioelectronic circuits and a graphical user interface for easy user configuration and monitoring. The system has integrated microfluidics to maintain its microphysiological environment within each well. The IMSIS platform currently incorporates O2, H2O2, and pH sensors inside each well, allowing up to six wells to perform concurrent measurements in real-time. Furthermore, the architecture is scalable to achieve an even higher level of throughput. The miniaturized design ensures portability, suitable for small offices and field applications. The IMSIS platform was successfully used to monitor in real-time the mitochondrial functions of live bovine embryos in O2 consumption, H2O2 release as an indication of ROS production, and extracellular acidity changes before and after the introduction of external substrates.

Keywords: Cellular metabolism; Electrochemical sensor; Extracellular acidity; Hydrogen peroxide sensor; Microphysiological system; Mitochondrial function; Oxygen sensor; ROS production; pH sensor

DOI: https://doi.org/10.1016/j.bios.2024.116595

Mikrochim Acta. 2024 08 07. 191(9): 523

Peptide hydrogel based electrochemical biosensor for simultaneous monitoring of H2O2 and NO released from three-dimensional cultured breast cancer cells.

Xue Wei, Xiaoxiao Zhao, Dandan Sui, Xu Chen, Wensheng Yang.

An antifouling peptide hydrogel-based electrochemical biosensor was developed for real-time monitoring of hydrogen peroxide (H2O2) and nitric oxide (NO) released by 3D cultured breast cancer cells upon drug stimulation. Platinum nanoparticles (Pt NPs) were electrodeposited on titanium mesh (Pt NPs/TM) to enhance sensitivity and shown to possess excellent electrocatalytic ability toward H2O2 and NO. The composite hydrogel formed by co-assembling of N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) and a fluorine methoxycarbonyl group-functionalized Lys-(Fmoc)-Asp was coated on Pt NPs/TM electrode surface to provide cellular scaffolding. Their favorable biocompatibility promoted cell adhesion and growth, while good hydrophilicity endowed the sensor with greatly enhanced antifouling capability in complex cell culture environments. The biosensor successfully determined H2O2 and NO secretion from both non-metastatic and metastatic breast cancer cells in real time. Our results demonstrated robust associations between reactive oxygen species (ROS) and reactive nitrogen species (RNS) production and cell malignancy, with the main difference in oxidative stress between the two subtypes of cells being NO release, particularly emphasizing RNS's critical leading in driving cancer metastasis and invasion progression. This sensor holds great potential for cell-release research under the in vivo-like microenvironment and could reveal RNS as an attractive therapeutic target for treating breast cancer.

Keywords: 3D cell culture; Antifouling; Electrochemical cell sensors; Metastatic/non-metastatic; Peptide hydrogel; ROS/RNS

DOI: https://doi.org/10.1007/s00604-024-06594-9

Dev Biol. 2024 Aug 06. pii: S0012-1606(24)00208-2. [Epub ahead of print]

Visualizing metabolic regulation using metabolic biosensors during sea urchin embryogenesis.

Aidan Furze, Ashley Waldron, Mamiko Yajima.

Growing evidence suggests that metabolic regulation directly influences cellular function and development and thus may be more dynamic than previously expected. In vivo and in real-time analysis of metabolite activities during development is crucial to test this idea directly. In this study, we employ two metabolic biosensors to track the dynamics of pyruvate and oxidative phosphorylation (Oxphos) during the early embryogenesis of the sea urchin. A pyruvate sensor, PyronicSF, shows the signal enrichment on the mitotic apparatus, which is consistent with the localization patterns of the corresponding enzyme, pyruvate kinase (PKM). The addition of pyruvate increases the PyronicSF signal, while PKM knockdown decreases its signal, responding to the pyruvate level in the cell. Similarly, a ratio-metric sensor, Grx-roGFP, that reads the redox potential of the cell responds to DTT and H2O2, the known reducer and inducer of Oxphos. These observations suggest that these metabolic biosensors faithfully reflect the metabolic status in the cell during embryogenesis. The time-lapse imaging of these biosensors suggests that pyruvate and Oxphos levels change both spatially and temporarily during embryonic development. Pyruvate level is increased first in micromeres compared to other blastomeres at the 16-cell stage and remains high in ectoderm while decreasing in endomesoderm during gastrulation. In contrast, the Oxphos signal first decreases in micromeres at the 16-cell stage, while it increases in the endomesoderm during gastrulation, showing the opposite trend of the pyruvate signal. These results suggest that metabolic regulation is indeed both temporally and spatially dynamic during embryogenesis, and these biosensors are a valuable tool to monitor metabolic activities in real-time in developing embryos.

Keywords: embryonic development; metabolic regulation; pyruvate sensor; sea urchin

DOI: https://doi.org/10.1016/j.ydbio.2024.08.003

Small. 2024 Aug 05. e2400671

Bio-Inspired Carbon Dots as Malondialdehyde Indicator for Real-Time Visualization of Lipid Peroxidation in Depression.

Xiaoyan Wu, Hao Cai, Rui Liao, Antonio Claudio Tedesco, Zijian Li, Feng Wang, Hong Bi.

Brain lipidic peroxidation is closely associated with the pathophysiology of various psychiatric diseases including depression. Malondialdehyde (MDA), a reactive aldehyde produced in lipid region, serves as a crucial biomarker for lipid peroxidation. However, techniques enabling real-time detection of MDA are still lacking due to the inherent trade-off between recognition dynamics and robustness. Inspired by the structure of phospholipid bilayers, amphiphilic carbon dots named as CG-CDs targeted to cell membrane are designed for real-time monitoring of MDA fluctuations. The design principle relies on the synergy of dynamic hydrogen bonding recognition and cell membrane targetability. The latter facilitates the insertion of CG-CDs into lipid regions and provides a hydrophobic environment to stabilize the labile hydrogen bonding between CG-CDs and MDA. As a result, recognition robustness and dynamics are simultaneously achieved for CG-CDs/MDA, allowing for in situ visualization of MDA kinetics in cell membrane due to the instant response (<5 s), high sensitivity (9-fold fluorescence enhancement), intrinsic reversibility (fluorescence on/off), and superior selectivity. Subsequently, CG-CDs are explored to visualize nerve cell membrane impairment in depression models of living cells and zebrafish, unveiling the extensive heterogeneity of the lipid peroxidation process and indicating a positive correlation between MDA levels and depression.

Keywords: carbon dots; depression; dynamic hydrogen bonding; lipid peroxidation; malonaldehyde

DOI: https://doi.org/10.1002/smll.202400671