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Biology subjects

Cho, S.-W.

Publications and source records attributed to Cho, S.-W..

3 recordsLinked to original sources

Enhanced liver regeneration via targeted mRNA delivery for partial in vivo reprogramming

Recent studies suggest that injury-induced dedifferentiation, which leads to the formation of injury-responsive cells, contributes significantly to tissue repair across various organs, including the liver. Utilizing Yamanaka factors (Oct4, Sox2, Klf4, and c-Myc: OSKM) for in vivo partial reprogramming generates injury-responsive cells in the intestine, mirroring those derived from injury-induced dedifferentiation. Thus, the transgene induction of OSKM or viral delivery of Oct4, Sox2, and Klf4 shows promise in facilitating tissue regeneration in the intestine, liver, skeletal muscle, and retina. Herein, we demonstrated that transient OSKM induction produces two distinct liver progenitor-like cell populations. One of these populations resembles liver progenitor-like cells (LPLCs) generated by acute acetaminophen (APAP) injury without triggering immune responses. To explore in vivo reprogramming as a viable strategy for tissue regeneration, we employed lipid nanoparticles (LNP) carrying OSKM mRNA (OSKM mRNA-LNP) to stimulate LPLCs formation. Notably, the production of Sox9+ LPLCs, and OSKM-induced dedifferentiation, was closely correlated with successful tissue regeneration in the liver post APAP injury. Thus, the OSKM mRNA-LNP approach represents a promising therapeutic intervention for the repair of acute liver injuries.

physiology↗

Characterization and analysis of neuronal signaling using microelectrode array combined with rapid and localized cooling device for cryo-neuromodulation

Cryoanesthesia--a purely physical anesthesia treatment that freezes tissue and attenuate nerve activity--can provide fast treatment through freezing and thawing of cryo-machine and is inexpensive compared to other anesthetics. However, cryoanesthesia has not been widely adopted because securing safe and effective conditions requires quantitative measurement and analysis of neuronal signaling during freezing and recovery, for which research tools are limited. A lack of rapid and localized cooling technologies for quantitative cellular level analysis, in particular, hinders research on not only the optimal cryo-modulation of neuronal activities but also its influence to neighboring cells via cellular networks. Here, we introduce a novel cryo-neuromodulation platform, a high-speed precision probe-type cooling device ([~]20{degrees}C/s at cooling) that provides localized cooling combined with a microelectrode array (MEA) system. We explored the temperature conditions for efficient silencing and recovery of neuronal activities without cell damage. We found that electrical activities of neurons were fully recovered within 1 minute of cooling duration with the maximum cooling speed, which was also confirmed with calcium imaging. The impact of silenced neurons on the neighboring neural network was explored using the localized cooling and we perceived that its influence can be transmitted if the neuronal network is well organized. Our new cryo-device provides rapid and reversible control of neural activities, which allows not just quantitative analysis of the network dynamics, but also new applications in clinical settings.

neuroscience↗

Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo

Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes, and is a major goal in the field of mechanobiology. However, existing biosensors for 3D tissue mechanics, primarily based on fluorescent emissions and deformable materials, are limited for in vivo measurement due to the limited light penetration and poor material stability inside intact, living organisms. While magneto-motive ultrasound (MMUS), which uses superparamagnetic nanoparticles as imaging contrast agents, has emerged as a promising modality for real-time in vivo imaging of tissue mechanics, it has poor sensitivity and spatiotemporal resolution. To overcome these limitations, we introduce magneto-gas vesicles (MGVs), a unique class of protein nanostructures based on gas vesicles and magnetic nanoparticles that produces differential ultrasound signals in response to varying mechanical properties of surrounding tissues. These hybrid protein nanostructures significantly improve signal strength and detection sensitivity. Furthermore, MGVs enable non-invasive, long-term, and quantitative measurement of mechanical properties within 3D tissues and organs in vivo. We demonstrated the performance of MGV-based mechano-sensors in vitro, in fibrosis models of organoids, and in vivo in mouse liver fibrosis models.

biochemistry↗