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Biology subjects

Ostmann, K.

Publications and source records attributed to Ostmann, K..

2 recordsLinked to original sources

Bacterial Engineered Living Materials modulate Mechanosignaling in Mammalian Cells

Engineered living materials (ELMs) are gaining momentum for biomedical applications as self-replenishing drug depots, smart wound dressings, or as wearable sensors. Current studies on ELM-host interaction are mainly limited to the exchange of biochemical cues between ELMs and surrounding cells and tissues. Here we show that the genetically programmed mechanical properties of ELMs modulate mechanosignaling pathways in mammalian cells cultivated onto the living materials. To this aim, we genetically modulated curli fiber production in E. coli and analyzed the impact on the mechanical properties of the resulting ELMs. The living materials were used as matrix for the cultivation of mammalian cells engineered with a fluorescent reporter to indicate the activation of the mechano-responsive Hippo signaling pathway. We demonstrate that different genetically programmed ELM compositions translated into differential regulation of mechanosignaling in mammalian cells. These findings provide the perspective of using ELMs as extracellular matrix with genetically programmable mechanics for mammalian cells while also highlighting the need to consider the mechanical properties of therapeutic ELMs when assessing interaction with surrounding tissues. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=156 SRC="FIGDIR/small/620857v1_ufig1.gif" ALT="Figure 1"> View larger version (68K): org.highwire.dtl.DTLVardef@1a1ef9borg.highwire.dtl.DTLVardef@79c49forg.highwire.dtl.DTLVardef@5bb04dorg.highwire.dtl.DTLVardef@193a808_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOToC figureC_FLOATNO C_FIG

bioengineering↗

Influence of formaldehyde on signaling pathways when used in mammalian cell culture

Formaldehyde is the smallest existing aldehyde, a highly reactive color less gas at room temperature and ubiquitously present in our atmosphere. Because of its reactivity leading to the crosslinking of macromolecules like proteins, it is widely used in industrial applications, but also in cell biology in order to preserve cells and tissues for further analysis. In this work, we show that formaldehyde releasing solutions commonly used for fixation of cells, can diffuse via the gas phase to the neighboring well and influence signaling processes in the therein cultured cells. To analyze this effect, we utilized a stable reporter cell line for YAP signaling or a gene expression-based reporter for activation of the NF-{kappa}B pathway. Especially the stable reporter cell line can also be used as sensor for bioavailable formaldehyde. The observed impact of formaldehyde on cellular signaling underscores the need for careful planning of experimental protocols and emphasizes the importance of implementing proper controls when utilizing this reagent in cellular signaling analyses.

cell biology↗