Woojung Shin

Significance Identification of the trigger of human intestinal inflammation can be a compelling clinical strategy for developing effective and target-specific antiinflammatory therapeutics. The pathomimetic “gut inflammation-on-a-chip” inspired by dextran sodium sulfate (DSS)-induced colitis models in mice enabled the independent uncoupling of complex inflammatory cross-talks and the combinatorial recoupling of individual contributing factors one at a time to identify the initiator of inflammato

The majority of human gut microbiome is comprised of obligate anaerobic bacteria that exert essential metabolic functions in the human colon. These anaerobic gut bacteria constantly crosstalk with the colonic epithelium in a mucosal anoxic-oxic interface (AOI). However, <i>in vitro</i> recreation of the metabolically mismatched colonic AOI has been technically challenging. Furthermore, stable co-culture of the obligate anaerobic commensal microbiome and epithelial cells in a mechanically dynamic

We leveraged a human gut-on-a-chip (Gut Chip) microdevice that enables independent control of fluid flow and mechanical deformations to explore how physical cues and morphogen gradients influence intestinal morphogenesis. Both human intestinal Caco-2 and intestinal organoid-derived primary epithelial cells formed three-dimensional (3D) villi-like microarchitecture when exposed to apical and basal fluid flow; however, 3D morphogenesis did not occur and preformed villi-like structure involuted whe

Human intestinal morphogenesis establishes 3D epithelial microarchitecture and spatially organized crypt-villus characteristics. This unique structure is necessary to maintain intestinal homeostasis by protecting the stem cell niche in the basal crypt from exogenous microbial antigens and their metabolites. Also, intestinal villi and secretory mucus present functionally differentiated epithelial cells with a protective barrier at the intestinal mucosal surface. Thus, re-creating the 3D epithelia

In a conventional culture of three-dimensional human intestinal organoids, extracellular matrix hydrogel has been used to provide a physical space for the growth and morphogenesis of organoids in the presence of exogenous morphogens such as Wnt3a. We found that organoids embedded in a dome-shaped hydrogel show significant size heterogeneity in different locations inside the hydrogel. Computational simulations revealed that the instability and diffusion limitation of Wnt3a constitutively generate

Polydimethylsiloxane (PDMS) is a silicone polymer that has been predominantly used in a human organ-on-a-chip microphysiological system. The hydrophobic surface of a microfluidic channel made of PDMS often results in poor adhesion of the extracellular matrix (ECM) as well as cell attachment. The surface modification by plasma or UV/ozone treatment in a PDMS-based device produces a hydrophilic surface that allows robust ECM coating and the reproducible attachment of human intestinal immortalized

The human gut-on-a-chip has demonstrated <i>in vivo</i>-relevant cellular fidelity and physiological functions of Caco-2 intestinal epithelium compared to its static cultures. However, transcriptomic dynamics that controls the morphogenic and mechanodynamic perturbation of Caco-2 epithelium in a microphysiological culture remain elusive. Single-cell transcriptomic analysis revealed that a gut-on-a-chip culture drives three clusters that illustrate distinct gene expressions and their spatial repr

A microengineered human gut-on-a-chip has demonstrated intestinal physiology, three-dimensional (3D) epithelial morphogenesis, and longitudinal host-microbiome interactions in vitro. The modular accessibility and modularity of the microphysiological gut-on-a-chip can lead to the identification of the seminal trigger in intestinal inflammation. By coupling microbial and immune cells in a spatiotemporal manner, we discovered that the maintenance of healthy epithelial barrier function is necessary

Human-induced pluripotent stem cells (hiPSCs) have facilitated studies on organ development and differentiation into specific lineages in in vitro systems. Although numerous studies have focused on cellular differentiation into neural lineage using hPSCs, most studies have initially evaluated embryoid body (EB) formation, eventually yielding terminally differentiated neurons with limited proliferation potential. This study aimed to establish human primitive neural stem cells (pNSCs) from exogene

In this study, we use low-cost spray deposition to study the possibility of using an earth-abundant ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> film as a antireflection and passivation layer on p-type Si. Structural, optical and electrical properties of the spray-deposited ZrO2 film were investigated. Spray deposited ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> is highly t